EP1602205A1 - Method and network-side facility for determining a path in a radio communications system - Google Patents

Method and network-side facility for determining a path in a radio communications system

Info

Publication number
EP1602205A1
EP1602205A1 EP04707927A EP04707927A EP1602205A1 EP 1602205 A1 EP1602205 A1 EP 1602205A1 EP 04707927 A EP04707927 A EP 04707927A EP 04707927 A EP04707927 A EP 04707927A EP 1602205 A1 EP1602205 A1 EP 1602205A1
Authority
EP
European Patent Office
Prior art keywords
radio station
radio
path
stations
station
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP04707927A
Other languages
German (de)
French (fr)
Inventor
Hui Li
Egon Schulz
Gerhard Stortz
Dan Yu
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Nokia Solutions and Networks GmbH and Co KG
Original Assignee
Siemens AG
Nokia Siemens Networks GmbH and Co KG
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Siemens AG, Nokia Siemens Networks GmbH and Co KG filed Critical Siemens AG
Priority to EP04707927A priority Critical patent/EP1602205A1/en
Publication of EP1602205A1 publication Critical patent/EP1602205A1/en
Withdrawn legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W40/00—Communication routing or communication path finding
    • H04W40/02—Communication route or path selection, e.g. power-based or shortest path routing
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W8/00—Network data management
    • H04W8/02—Processing of mobility data, e.g. registration information at HLR [Home Location Register] or VLR [Visitor Location Register]; Transfer of mobility data, e.g. between HLR, VLR or external networks
    • H04W8/04—Registration at HLR or HSS [Home Subscriber Server]
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W84/00—Network topologies
    • H04W84/18—Self-organising networks, e.g. ad-hoc networks or sensor networks

Definitions

  • the invention relates to a method for determining a path in a radio communication system with a plurality of at least partially mobile radio stations according to the preamble of claim 1
  • the invention relates to a network-side device in a radio communication system with a multiplicity of at least partially mobile radio stations according to the preamble of claim 7. 5
  • information for example control signals or useful data such as voice, images, short messages or other data
  • information is transmitted by means of electromagnetic waves via a radio interface between the transmitting and receiving radio stations.
  • Radio communication systems are often used as cellular systems e.g. trained according to the standard GSM (Global System for Mobile Communication) or UMTS (Universal Telecommunications System) with a 5 network infrastructure consisting of base stations, devices for controlling and controlling the base stations and other network-side devices.
  • GSM Global System for Mobile Communication
  • UMTS Universal Telecommunications System
  • radio stations are able to establish a radio connection with one another without an intermediary central device.
  • the connection between two radio stations takes place either directly or over longer distances via other radio stations that form relay stations for this connection.
  • Useful information is thus sent from radio station to radio station over distances that correspond to the radio range of the radio station. cations correspond.
  • the radio stations of a self-organizing network can be mobile radio stations (for example mobile radio devices for people or in vehicles) and / or predominantly stationary radio stations (for example computers, printers, household appliances).
  • Examples of self-organizing networks are radio-based local networks (WLAN, Wireless Local Area Network) such as HiperLAN or IEEE 802.11.
  • a particular advantage of ad hoc networks is their great mobility and flexibility. However, these factors also represent a great challenge for routing methods.
  • a path from the transmitter possibly via several radio stations forwarding the data packet to the receiver, must be determined in order to transmit information from a transmitter to a receiver , This determination requires the transmission of a large amount of signaling information, so that under certain circumstances the need for radio resources to determine a path is undesirably large.
  • the selection of a path through a radio communication system is called routing. If the radio stations are mobile radio stations, the topology of the network usually changes over time.
  • the invention has for its object to provide a method and a network-side device of the type mentioned, which allow a resource-saving determination of a path in a radio communication system with a plurality of at least partially mobile radio stations.
  • the radio communication system comprises a plurality of at least partially mobile radio stations.
  • a radio station which is located in a radio coverage area of another radio station is referred to as an adjacent radio station to the other radio station.
  • information can be transmitted from a first radio station as a transmitting radio station to a second radio station as a receiving radio station directly or via one or more other radio stations receiving and transmitting the information via at least one path.
  • a path between the first and the second radio station consists of a sequence of radio stations which, in addition to the first radio station and the second radio station, may contain the radio stations receiving and transmitting the information in between.
  • both the first and the second radio station in order to determine at least one path between the first and the second radio station, both the first and the second radio station send a message to their neighboring or neighboring radio stations with identification information from the other radio station.
  • the radio communication system can contain both mobile and stationary radio stations.
  • mobile radio stations are mobile stations or laptops
  • stationary radio stations are base stations, radio access points or stationary computers with a radio connection. These radio stations can communicate with each other. It is possible that radio stations for communication with other radio stations have different types of radio interfaces with different radio coverage areas. For example, a mobile station may have a different radio coverage area for communication with a base station than for communication with another mobile station.
  • a radio station is adjacent to another radio station if it is currently in a radio coverage area of this other Radio station is located.
  • the radio coverage area which relates to the communication between these two radio stations, is relevant for checking whether two radio stations represent adjacent radio stations.
  • a mobile station is, for example, adjacent to another mobile station if it is currently within a radio coverage area of the other mobile station used for communication with mobile stations.
  • a radio station within the radio communication system under consideration can have any number of neighboring radio stations.
  • Information can be transmitted in the radio communication system from a first radio station to a second radio station. If these two radio stations are adjacent radio stations, the transmission of information can take place directly.
  • the information must be forwarded by other radio stations.
  • the information can then be received and forwarded by one or more other radio stations.
  • the information carries identification information from the second radio station.
  • the forwarding takes place in accordance with the above explanation in each case via neighboring radio stations. Forwarding is only possible via radio stations of the same type, such as mobile stations of the same type, and via radio stations of different types, such as mobile stations and base stations.
  • the information is transmitted in the radio communication system via a path.
  • This path consists first of all of the first radio station, which emits the information first, then of the radio station or stations transmitting the information, and, lastly, of the second radio station which ultimately receives the information.
  • the first and the second radio station send out a message. each sent in particular to all neighbors of the radio stations transmitting this message (broadcast).
  • the transmitted message carries identification information of the other radio station.
  • the message sent by the first radio station to determine at least one path thus carries identification information from the second radio station, and the message sent by the second radio station carries identification information from the first radio station.
  • the messages are emitted by the first and the second radio station without having received a similar message from a neighboring radio station immediately beforehand to determine a path between the first and the second radio station, so the messages do not consist of forwarding messages to determine a path.
  • neither of the two radio stations has received the message from the other radio station before it sends its own message. Both messages thus trigger a method for determining the same path or the same paths by the radio communication system at different locations in the radio communication system. Due to the transmission of the message for determining a path by the first and by the second radio station, it is a bidirectional procedure for determining the path.
  • the first and the second radio station are requested to send the respective message by a network-side device of the radio communication system.
  • This request can be made via a radio station.
  • the request can contain the identification information of the respective other radio station.
  • Such a request allows a mixture of a central one, controlled by a network-side device, and a decentralized one, carried out by individual radio stations. led, determination of at least one path between the first and the second radio station.
  • the first radio station Before the request, the first radio station preferably informs the network device of a future transmission of information from the first to the second radio station.
  • the first radio station can also request information about at least one path between the first and the second radio station from the network-side device before the request.
  • the neighboring or neighboring radio stations which have received the respective message forward the respective message to their respective neighboring or neighboring radio stations after adding identification information.
  • a radio station which has received a message for determining at least one path between the first and the second radio station can thus add its own identification information to this message.
  • the corresponding radio station forwards the message modified in this way.
  • This method can be used accordingly for the radio station or the radio stations which subsequently receive the modified message. In this way, a message is created which comprises a series of identification information. This series of identification information then corresponds to a path through the radio communication system.
  • a radio station advantageously transmits both a message from the first radio station, possibly with identification information added by one or more radio stations, and a message, if appropriate, from the second radio station with identification information added from one or more radio stations has received information about a path between the first and the second radio station to the first and / or the second radio station, possibly via one or more further radio stations, using the information about the path.
  • the at least one radio station has thus received two related messages from the first and the second radio station, possibly via other radio stations, which are used to determine a path between the first and the second radio station.
  • the at least one radio station can recognize that the two messages belong together from identification information of the messages and / or from the fact that both messages are used to determine a path between the first and the second radio station.
  • a path through the radio communication system is known to the at least one radio station. This at least one radio station can then transmit information about this path to the first and / or to the second radio station. The at least one radio station can be used for this transmission
  • the information about the path between the first and the second radio station is thus transmitted on one or more parts of the path between the first and the second radio station.
  • the first and / or the second radio station can gain knowledge of the path thus determined between the first and the second radio station.
  • This path can then be sent to send information from the first to the second radio station.
  • the path can be inserted into a header of the information to be transmitted.
  • the at least one path to be determined between the first and the second radio station represents part of an overall path between the first radio station as the transmitting radio station and another radio station as the receiving radio station, or represents part of a total path between a radio station other than the first radio station as the transmitting radio station and the second radio station as the receiving radio station, or part of a total path between a radio station other than the first and the second radio station and a further other than the first and the second radio station
  • the method according to the invention can be used simultaneously by several pairs of radio stations, and thus an overall path, which is composed of several individual paths, can be determined. This procedure corresponds to a multidirectional method for determining a path, since in this case the method can be initiated at approximately the same time from more than two locations in the radio communication system.
  • the network-side device has means for selecting at least two radio stations from at least one path between the first and the second radio station, which are each requested to send a message to determine the at least one path.
  • the request to the at least two radio stations can be carried out directly by the network-side device according to the invention, or else on request by the network-side device by other radio stations.
  • the path to be determined is not known to the network device when selecting the at least two radio stations. Rather, the network-side device determines points of the path to be determined in the form of the selected radio station by selecting at least two radio stations. This selection the at least two radio stations can be based on different criteria. Examples of criteria are a location dependency of the selected radio stations, for example radio stations in the middle or at the edge of a geographical area or a radio cell, or also from each radio cell through which the path to be specifically determined is to run, can be at least one radio station be selected. Other examples are the signal strength of radio signals from radio stations or a random mechanism for selecting radio stations.
  • the network-side setup it can e.g. be a base station or a device connected to one or more base stations.
  • the network-side device has means for storing neighborhood relationships between the radio stations of the radio communication system. This can be, for example, a table in which the current neighboring radio stations are listed for each radio station of the radio communication system.
  • the network device according to the invention is particularly suitable for carrying out the method according to the invention. Further devices and means for carrying out the method according to the invention can be provided in the network-side device.
  • FIG. 1 part of a radio communication system
  • FIG. 2 a first sequence diagram of a method according to the invention
  • FIG. 3 a schematic illustration of a sequence of a method according to the invention in a radio communication system
  • FIG. 4 a second flow chart of a method according to the invention
  • FIG. 5a a first pictorial representation of an advantage of the method according to the invention
  • Figure 5b a second pictorial representation of an advantage of the method according to the invention.
  • FIG. 1 shows a section of a radio communication system.
  • This comprises three base stations BSA, BSB and BSC.
  • the subscriber-side radio stations AI, A2, A3, A4, A5, B1, B2, B3, Cl, C2, C3, C4 and C5 are present in the radio communication system.
  • the radio stations AI, A2, A3, A4 and A5 are located in the radio cell A of the base station BSA. Accordingly, the radio stations B1, B2 and B3 are currently in the radio cell B of the base station BSB and the radio stations C1, C2, C3, C4 and C5 are in the radio cell C of the base station BSC.
  • the core network CN contains a network-side device NE and is connected to the base stations BSA, BSB and BSC.
  • the radio station AI wants to send information to the radio station C1.
  • the radio communication system under consideration is a mixture of a cellular radio communication system and a radio-supported local area network (WLAN, Wireless Local Area Network).
  • WLAN Wireless Local Area Network
  • This mixed character of the radio communication system under consideration manifests itself in the fact that, on the one hand, this data is forwarded from radio station to radio station for the transmission of data between the individual radio stations, and that, on the other hand, the core network or the base stations are required for certain functions.
  • This information is forwarded via a path from radio station to radio station.
  • a radio station can forward information to another radio station in its radio coverage area. Radio stations located in their respective radio coverage areas are neighboring radio cells.
  • the radio stations AI, A2, A3, A4, A5, B1, B2, B3, Cl, C2, C3, C4 and C5 each have a similar first radio range, which is significantly smaller than the radio range of the base stations BSA, BSB and BSC.
  • the radio range of the base stations BSA, BSB and BSC corresponds at least to the radius of the radio cells A, B and C.
  • the radio stations AI, A2, A3, A4, A5, B1, B2, B3, Cl, C2, C3, C4 and C5 also have a larger second radio range, on the basis of which they can communicate with the base stations BSA, BSB and BSC.
  • the radio stations AI, A2, A3, A4, A5, B1, B2, B3, Cl, C2, C3, C4 and C5 have two radio ranges, the first one for communication between the radio stations AI, A2, A3, A4, A5, Bl, B2, B3, Cl, C2, C3, C4 and C5 is used, and the second for communication with the base stations BSA, BSB and BSC.
  • the radio station AI now intends to send information about other radio stations to the radio station C1.
  • the radio station AI must know a path through the radio communication system.
  • a path could consist, for example, of the following series of radio stations: AI, A2, A3, B1, B3, C2, C5 and Cl.
  • the radio stations AI, A2, A3, B1, B3, C2, C5 and Cl mentioned are each adjacent in pairs, so that they can receive and forward the information. So that the information which the radio station AI sends is forwarded to the radio station C1 via the path known to it, information about this path is contained in a header of the information.
  • a radio station receiving the information knows from the information about the path that it should forward the information along the path. This procedure continues until the radio station C1 uses the path or other information about the addressee of the information to recognize that it is the ultimate recipient of the information, who evaluates the information and does not forward it.
  • the radio station AI can first check in a memory connected to it whether it knows a path to the radio station C1. Such storage of paths by the radio communication system is particularly helpful when the radio communication system has a plurality of stationary, i.e. not mobile, radio stations. This includes base stations, for example, which can also be used to forward the information. If, on the other hand, the radio communication system has a large number of mobile radio stations, the positions of these radio stations generally change over time, so that paths can lose their topicality after a certain time. In this case, the use of saved path tables can be omitted, or the paths of the tables are automatically deleted after a specified time and are therefore no longer used without checking.
  • FIG. 2 shows a method according to the invention for determining a suitable path through the radio communication system of FIG. 1.
  • the radio station AI sends a message DNID (Destination Node Identification) to the base station BSA.
  • the notification DNID contains a request to the base station BSA or the core network CN to check whether the radio station C1 is registered in the radio communication system. This check can be carried out in the core network CN using various tables or registers, such as an HLR (Home Location Register) or a VLR (Visitor Location Register) occur.
  • HLR Home Location Register
  • VLR Visitor Location Register
  • the base station BSA then sends a message RDST (Route Discovery Start) to the radio station AI, with which the radio station AI is requested to initiate the method for determining the path to the radio station C1 by sending a suitable broadcast message.
  • the base station BSC also sends a corresponding message RDST to the radio station C1.
  • the radio station C1 is requested to likewise initiate the procedure for determining a suitable path between the radio station C1 and the radio station AI by sending out a broadcast message.
  • the radio station AI based on its request DNID the end point of the searched path in the form of the
  • Radio station C1 is already known, the radio station C1 is informed by the RDST message from the base station BSC of identification information from the radio station AI, which for the radio station C1 represents the end point of the path to be determined.
  • the radio station AI then sends out a RREQ (Route Request) message.
  • This message RREQ is broadcast via a broadcast call, so that all radio stations in the vicinity of the radio station AI are addressed by this message RREQ.
  • the message RREQ which is broadcast by the radio station AI, contains information that a path is sought between the radio station AI and the radio station C1.
  • a similar message RREQ is also broadcast by the radio station C1, which informs the radio stations that a path between the radio station C1 and the radio station AI is to be determined.
  • a message RREQ can contain an identification number of the path determination, information about a maximum number of radio stations which the path to be determined may contain and a field which indicates the number of forwardings of the message RREQ, and identification information of the first and the second radio station.
  • RREQ Forward message RREQ via broadcast call.
  • identification information from the same radio station is appended to the RREQ message by the radio station receiving and transmitting the RREQ message.
  • the radio station increases the field with the number of forwardings by the value one before forwarding the RREQ message. If the number of forwardings reaches the maximum number of radio stations which the path to be determined may contain - minus the first and the second radio station - the radio station rejects the RREQ message and does not forward it.
  • Radio station A5 is in the vicinity of the radio station AI. Radio station A5 thus receives the RREQ message from radio station AI ..
  • the radio station A5 After receiving the RREQ message, the radio station A5 hangs its identification information on the RREQ message and transmits the RREQ modified message in this way by broadcasting.
  • the radio station AI subsequently receives the message RREQ due to its proximity to the radio station A5, which is broadcast by the radio station A5. However, it recognizes from the RREQ message that it has already sent it itself and therefore does not forward the RREQ message again.
  • Each radio station which receives a RREQ message continues to check whether it has stored the searched path through the radio communication system in a memory. For example, would recognize the radio station A5 that it knows a path between the radio station AI and the radio station C1, it would not send a message RREQ, but would send the radio station AI a message which contains the path sought.
  • the radio station C5 also receives a message RREQ from the radio station C1, which indicates to it that a path between the radio station C1 and the radio station AI is being determined.
  • the radio station C5 checks whether such a path is possibly known to it from a memory. If this is not the case, it sends a RREQ message by broadcasting after it has added its identification information to it.
  • the general procedure for determining a path is as follows: the two radio stations AI and Cl initiate the procedure by sending a RREQ message by broadcasting.
  • This message RREQ contains the message that a path is sought between the radio stations AI and Cl.
  • each radio station that has received a RREQ message checks, if necessary using an identification number for determining the path, whether it has already received this message at an earlier point in time. If this is the case, this radio station does not respond to the RREQ message.
  • a radio station attaches its identification information to the message RREQ and also sends the message RREQ modified in this way by broadcasting. Furthermore, if a maximum number of radio stations per path is used, the corresponding counter can also be increased by the radio station. Since the message RREQ was sent both by the radio station AI and by the radio station C1, radio stations reach both messages RREQ from the side of the radio station AI, through which a path between the radio station AI and the radio station Cl is searched, and messages RREQ from on the part of the radio station Cl, through which a path between the radio station Cl and the radio station AI is searched.
  • FIG. 3 shows the case in which this situation first applies to the radio station B3.
  • the radio station B3 has thus received a message RREQ from the radio station B2, which it uses to recognize that a path between the radio station AI and the radio station C1 is being sought, and a message RREQ from the radio station C2, which can be used to recognize that a Path between radio station Cl and radio station AI is searched. Based on the contents of these two messages RREQ, the radio station B3 recognizes that these two messages RREQ relate to the same path to be determined.
  • the RREQ message from the radio station B2 contains identification information about the radio stations AI, A5 and B2. Accordingly, the RREQ message from the radio station C2 contains identification information about the radio stations C1, C5 and C2. The radio station B3 thus knows a path between the radio stations AI and Cl after receiving the two messages RREQ.
  • the radio station B3 then sends a message RREP (Route Reply) to the radio stations C2 and B2.
  • RREP Receive Reply
  • These RREP messages are not sent by broadcast call, but by using a single send call.
  • the radio station B3 uses the knowledge of the path between the radio stations AI and Cl.
  • the RREP messages contain information about the path between the radio stations AI and Cl. This information is forwarded by the radio stations in accordance with the sequence of the path between the radio stations AI and Cl to the transmitting radio station AI and to the receiving station Cl.
  • the path to be used for forwarding can be inserted in a header of the messages RREP.
  • the radio station B2 then recognizes, for example, that after its identification formation follows the identification information of the radio station A5, so that it sends a message RREP to the radio station A5.
  • the information about the path between the radio station AI and the radio station C1, which the radio station B3 sends out using the messages RREP, can also only be sent back to the radio station AI.
  • the radio station Cl which has initiated the method for determining the path, has no knowledge of the determined path between the radio stations AI and Cl.
  • the radio station AI wants to send information INFO to the radio station Cl, it is sufficient if only this knows the determined path between the radio stations AI and Cl.
  • the information about the path which the radio station B3 emits by means of the messages RREP to relate only to part of the path.
  • the radio station B3 can only transmit the partial path between the radio station AI and the radio station B3 to the radio station AI.
  • the radio station AI To send the information INFO from the radio station AI to the radio station Cl, the radio station AI then first sends via the part path known to it, whereupon the radio station B3 for the second part of the path between the radio station B3 and the radio station Cl sends the corresponding part path into the header of Inserts information.
  • the radio station AI has several paths available for sending the information INFO to the radio station C1.
  • the radio station AI can then make a suitable selection from these paths in order to send the information INFO to the radio station C1, or it can use several paths to send the information INFO to the radio station C1.
  • the two radio stations AI and C1 are used, which are the method for determining the path by sending a message the radio station that sends the information first and the radio station that ultimately receives the information.
  • the path between these two radio stations is therefore the total path via which the information is to be sent.
  • the path it is also possible for the path to be determined to represent only a partial path of an overall path via which information is to be sent.
  • the network-side device instructs a plurality of radio stations to send out a corresponding RREQ message to determine a path through the radio communication system.
  • FIG. 4 shows the case in which the network-side device NE of FIG. 1 sends a message RDST to the radio stations AI, B2 and Cl after receiving a message DNID from the radio station AI. This transmission takes place for the radio station AI using the base station BSA, for the radio station B2 using the base station BSB and for the radio station C1 using the base station BSC.
  • the addressed radio stations are asked to transmit messages RREQ to determine a path through the radio communication system by broadcasting.
  • the RDST message to the radio station AI contains the instruction to determine a path between the radio station AI and the radio station B2.
  • the instruction RDST to the radio station B2 contains the instruction to determine both a path between the radio station B2 and the radio station AI and also a path between the radio station B2 and the radio station C1.
  • the RDST message to the radio station C1 contains the instruction to determine a path between the radio station C1 and the radio station B2. This respective information is then to be added by the radio stations AI, B2 and Cl to the messages RREQ they broadcast.
  • the radio stations AI, B2 and Cl are selected by the network-side device NE using means Ml for selecting radio stations.
  • the network-side device NE knows the current topology, ie the neighborhood relationship between the different radio stations.
  • a method for determining the topology of the network can, for example, be as follows: each radio station sends a broadcast signal at regular intervals, in which it requests the respective neighboring radio stations to send a response. After receiving such a response from its or its neighboring radio stations, the corresponding radio station knows which radio stations are currently in its neighborhood. The radio station then sends this information to the network-side device NE via the corresponding base station.
  • the network-side device NE knows the entire topology of the network. The method is advantageously carried out several times, for example at periodically recurring times, in order to take into account the mobility and the availability of radio stations.
  • This topology can be stored in the network-side device NE using means M2 for storing neighborhood relationships.
  • the radio stations AI, B2 and C1 each send a message RREQ to determine the corresponding path after receiving the message RDST.
  • the method for determining the partial paths between the radio stations AI and B2 and between the radio stations B2 and C1 is analogous to the above description of the determination of the path between the radio stations AI and B1.
  • the radio station A5 received a message for determining the path between the radio stations AI and B2 from the radio station AI and from the radio station B2. Thereupon it sends a corresponding message RREP with information via the determined path to the radio stations AI and B2. For this transmission of the information about the path by means of the message RREP, the description regarding this signal RREP applies accordingly in accordance with the above description.
  • the radio station C2 also received a signal from the radio station C1 to determine a path between the radio stations C1 and B2, and a message RREQ from the radio station B2 to determine a path between the radio stations B2 and Cl. Thereupon, it sends information about the determined path between the radio stations B2 and C1 using the knowledge of this path via individual radio calls to the radio stations B2 and C1 via the radio stations C5 and B3.
  • the radio station B2 can continue to forward this information to the radio station AI via the path. However, the sending of information from the radio station AI to the radio station Cl is also possible without this forwarding of the partial path to the radio station AI.
  • the radio station AI can send the information INFO to the radio station C1 knowing the path via the radio stations A5, B2, B3, C2 and C5. With this procedure it is also possible that several paths between the radio station AI and the radio station Cl are determined. However, each of these paths contains the radio station B2. However, this fact proves to be problematic if the
  • Radio station B2 for forwarding the information INFO fails.
  • the network-side device NE can transmit a plurality of radio stations between the transmitting radio station AI and the receiving radio station C1 in order to transmit a message RREQ to determine a
  • a message RDST with the request to send a message RREQ could be sent to the radio station B1 in addition to the radio stations AI, B2 and C1.
  • the radio station B1 would then be instructed with the RDST message to determine a path between the radio station B1 and the radio station AI and to determine a path between the radio station B1 and radio station C1.
  • the radio station AI would be instructed with the message RDST to determine a path between the radio station AI and the radio station B2, as well as a path between the radio station AI and the radio station B1.
  • the radio station C1 would be asked to determine a path between the radio station C1 and the radio station B2, as well as a path between the radio station C1 and the radio station B1.
  • at least two paths would be determined by the radio communication system, at least one path containing the radio station B2 and at least one further path containing the radio station B1.
  • the base device can request a base station to send a message to determine a partial path.
  • the base station concerned can send the information transmitted to it via partial paths to the network-side device.
  • the latter can transmit the relevant information to the radio station AI via the base station BSA or use it exclusively for updating the availabilities of radio stations within the radio communication system stored in the network-side device.
  • the described method according to the invention has the advantage that the number of signaling messages for determining a path through the radio communication system can be significantly reduced compared to conventional non-bidirectional methods.
  • FIGS. 5a and 5b illustrate schematically in FIGS. 5a and 5b.
  • the circle in FIG. 5a represents the area of the radio communication system within which messages from the radio stations of the radio communication system would have to be sent by radio to determine a path.
  • both the radio station AI and the radio station C1 transmit such a subsequent
  • the area of the two circles shows in FIG. 5b within which areas of the radio communication system corresponding messages for determining a path must be sent by the radio stations. It can be seen by comparing FIGS. 5a and 5b that the number of signaling messages is significantly reduced by a bidirectional procedure for determining a path through the radio communication system.
  • Another advantage can be seen in the fact that the path between the transmitting radio station and the receiving radio station can be found faster when using the method according to the invention than with conventional methods for determining a path. As a result, the connection between the transmitting and the receiving radio station can be established within a shorter period of time.
  • the method according to the invention can be used for the most varied sizes of radio communication systems, so scalability is available.
  • the method can be used within a single radio cell or, as shown in FIG. 3, for a plurality of radio cells.

Abstract

The invention relates to a method for determining a path in a radio communications system comprising a multitude of at least partially mobile radio stations (BSA, BSB, BSC, A1, A2, A3, A4, A5, B1, B2, B3, C1, C2, C3, C4, C5) of which one radio station that is located in a radio coverage area of another radio station constitutes a radio station that is adjacent to the other radio station. In the radio communications system, items of information can be transmitted by a first radio station (A1), which serves as a transmitting radio station, to a second radio station (C1), which serves as a receiving radio station, over at least one path directly or via one or more other radio stations (A5, B2, B3, C2, C5) that receive and relay the items of information. A path between the first (A1) and the second (C1) radio station consists of a succession of radio stations (A1, A5, B2, B3, C2, C5, C1) that, in addition to the first radio station (A1) and the second radio station (C1), optionally include the radio stations (A5, B2, B3, C2, C5), which are located in the succession between the first and second radio stations and which receive and relay the items of information. In order to determine at least one path between the first (A1) and the second (C1) radio station, the invention provides that both the first (A1) as well as the second (C1) radio station each send a message containing identification information from the respective other radio station (A1, C1) to their respective adjacent radio station(s) (A5, C5). The invention also relates to a network-side facility (NE) for carrying out the method.

Description

VERFAHREN UND NETZSEITIGE EINRICHTUNG ZUR ERMITTLUNG EINES PFADES IN EINEM ADHOC FUNKKOMMUNIKATIONSSYSTEMMETHOD AND NETWORK-SIDED DEVICE FOR DETERMINING A PATH IN AN ADHOC RADIO COMMUNICATION SYSTEM
Die Erfindung betrifft ein Verfahren zur Ermittlung eines Pfades in einem FunkkoramunikationsSystem mit einer Vielzahl von zumindest teilweise mobilen Funkstationen nach dem Oberbegriff des Anspruchs 1. 0The invention relates to a method for determining a path in a radio communication system with a plurality of at least partially mobile radio stations according to the preamble of claim 1
Weiterhin betrifft die Erfindung eine netzseitige Einrichtung in einem Funkkommunikationssystem mit einer Vielzahl von zumindest teilweise mobilen Funkstationen nach dem Oberbegriff des Anspruchs 7. 5Furthermore, the invention relates to a network-side device in a radio communication system with a multiplicity of at least partially mobile radio stations according to the preamble of claim 7. 5
In Funkkommunikationssystemen werden Informationen (beispielsweise Steuersignale oder Nutzdaten wie Sprache, Bilder, Kurznachrichten oder andere Daten) mittels elektromagnetischer Wellen über eine Funkschnittstelle zwischen Sende- und 0 Empfangsfunkstation übertragen.In radio communication systems, information (for example control signals or useful data such as voice, images, short messages or other data) is transmitted by means of electromagnetic waves via a radio interface between the transmitting and receiving radio stations.
Funkkommunikationssyste e sind oftmals als zellulare Systeme z.B. nach dem Standard GSM (Global System for Mobile Communi- cation) oder UMTS (Universal Telecommunications System) mit 5 einer Netzinfrastruktur bestehend aus Basisstationen, Einrichtungen zur Kontrolle und Steuerung der Basisstationen und weiteren netzseitigen Einrichtungen ausgebildet.Radio communication systems are often used as cellular systems e.g. trained according to the standard GSM (Global System for Mobile Communication) or UMTS (Universal Telecommunications System) with a 5 network infrastructure consisting of base stations, devices for controlling and controlling the base stations and other network-side devices.
In einem Adhoc-Modus eines Funkkommunikationssystems (in die- 0 sem Fall auch selbstorganisierendes Netz genannt) sind Funkstationen in der Lage, ohne eine vermittelnde zentrale Einrichtung eine Funkverbindung untereinander aufzubauen. Die Verbindung zwischen zwei Funkstationen erfolgt dabei entweder direkt oder bei größeren Entfernungen über weitere Funkstati- 5 onen, die für diese Verbindung Relaisstationen bilden. Nutzinformationen werden somit von Funkstation zu Funkstation ü- ber Abstände gesendet, welche der Funkreichweite der Funksta- tionen entsprechen. Die Funkstationen eines selbstorganisierenden Netzes können mobile Funkstationen (beispielsweise Mobilfunkgeräte von Personen oder in Verkehrsfahrzeugen) und/oder vorwiegend stationäre Funkstationen (beispielsweise Computer, Drucker, Haushaltsgeräte) sein. Beispiele für selbstorganisierende Netze sind funkgestützte lokale Netze (WLAN, Wireless Local Area Network) wie HiperLAN oder IEEE 802.11.In an ad hoc mode of a radio communication system (in this case also called a self-organizing network), radio stations are able to establish a radio connection with one another without an intermediary central device. The connection between two radio stations takes place either directly or over longer distances via other radio stations that form relay stations for this connection. Useful information is thus sent from radio station to radio station over distances that correspond to the radio range of the radio station. cations correspond. The radio stations of a self-organizing network can be mobile radio stations (for example mobile radio devices for people or in vehicles) and / or predominantly stationary radio stations (for example computers, printers, household appliances). Examples of self-organizing networks are radio-based local networks (WLAN, Wireless Local Area Network) such as HiperLAN or IEEE 802.11.
Ein besonderer Vorteil von Adhoc Netzen liegt in ihrer großen Mobilität und Flexibilität. Diese Faktoren stellen jedoch auch eine große Herausforderung für Routing Verfahren dar. In einem aus mehreren Funkstationen bestehenden Funkkommunikati- onssystem muss zur Übermittlung von Informationen von einem Sender zu einem Empfänger ein Pfad von dem Sender gegebenenfalls über mehrere das Datenpaket weiterleitende Funkstationen zu dem Empfänger ermittelt werden. Diese Ermittlung bedarf der Übertragung einer Vielzahl von Signalisierungsinfor- mation, so dass unter Umständen der Bedarf an Funkressourcen zur Ermittlung eines Pfades unerwünscht groß ist. Die Auswahl eines Pfades durch ein Funkkommunikationssystem bezeichnet man als Routing. Handelt es sich bei den Funkstationen um mobile Funkstationen, so ändert sich in der Regel die Topologie des Netzwerkes mit der Zeit.A particular advantage of ad hoc networks is their great mobility and flexibility. However, these factors also represent a great challenge for routing methods. In a radio communication system consisting of several radio stations, a path from the transmitter, possibly via several radio stations forwarding the data packet to the receiver, must be determined in order to transmit information from a transmitter to a receiver , This determination requires the transmission of a large amount of signaling information, so that under certain circumstances the need for radio resources to determine a path is undesirably large. The selection of a path through a radio communication system is called routing. If the radio stations are mobile radio stations, the topology of the network usually changes over time.
Der Erfindung liegt die Aufgabe zugrunde, ein Verfahren und eine netzseitige Einrichtung der eingangs genannten Art aufzuzeigen, welche eine ressourcensparende Ermittlung eines Pfades in einem Funkkommunikationssystem mit einer Vielzahl von zumindest teilweise mobilen Funkstationen erlauben.The invention has for its object to provide a method and a network-side device of the type mentioned, which allow a resource-saving determination of a path in a radio communication system with a plurality of at least partially mobile radio stations.
Diese Aufgabe wird hinsichtlich des Verfahrens gelöst durch ein Verfahren mit den Merkmalen des Anspruchs 1.With regard to the method, this object is achieved by a method having the features of claim 1.
Vorteilhafte Ausgestaltungen und Weiterbildungen sind Gegenstand von abhängigen Ansprüchen. Das Funkkommunikationssystem umfasst eine Vielzahl von zumindest teilweise mobilen Funkstationen. Eine Funkstation, welche sich in einem Funkabdeckungsbereich einer anderen Funkstation befindet, wird als benachbarte Funkstation zu der an- deren Funkstation bezeichnet. In dem Funkkommunikationssystem sind Informationen von einer ersten Funkstation als Sendefunkstation zu einer zweiten Funkstation als Empfangsfunkstation direkt oder über eine oder mehrere andere die Informationen empfangende und weiterleitende Funkstationen über in- destens einen Pfad übertragbar. Hierbei besteht ein Pfad zwischen der ersten und der zweiten Funkstation aus einer Reihenfolge von Funkstationen, welche außer der ersten Funkstation und der zweiten Funkstation gegebenenfalls die in der Reihenfolge dazwischenliegenden die Informationen empfangen- den und weiterleitenden Funkstationen beinhaltet.Advantageous refinements and developments are the subject of dependent claims. The radio communication system comprises a plurality of at least partially mobile radio stations. A radio station which is located in a radio coverage area of another radio station is referred to as an adjacent radio station to the other radio station. In the radio communication system, information can be transmitted from a first radio station as a transmitting radio station to a second radio station as a receiving radio station directly or via one or more other radio stations receiving and transmitting the information via at least one path. Here, a path between the first and the second radio station consists of a sequence of radio stations which, in addition to the first radio station and the second radio station, may contain the radio stations receiving and transmitting the information in between.
Erfindungsgemäß sendet zur Ermittlung von mindestens einem Pfad zwischen der ersten und der zweiten Funkstation sowohl die erste als auch die zweite Funkstation jeweils an ihre be- nachbarte oder benachbarten Funkstationen eine Nachricht mit Identifikationsinformationen von der jeweils anderen Funkstation.According to the invention, in order to determine at least one path between the first and the second radio station, both the first and the second radio station send a message to their neighboring or neighboring radio stations with identification information from the other radio station.
Das Funkkommunikationssystem kann sowohl mobile als auch sta- tionäre Funkstationen enthalten. Beispiele für mobile Funkstationen sind Mobilstationen oder Laptops, Beispiele für stationäre Funkstationen sind Basisstationen, Funkzugangspunkte oder stationäre Computer mit Funkanschluss . Diese Funkstationen können miteinander kommunizieren. Es ist ög- lieh, dass Funksstationen zur Kommunikation mit anderen Funkstationen verschiedenartige Funkschnittstellen mit unterschiedlichen Funkabdeckungsbereichen aufweisen. So kann eine Mobilstation zum Beispiel zur Kommunikation mit einer Basisstation einen anderen Funkabdeckungsbereich aufweisen als zur Kommunikation mit einer anderen Mobilstation. Eine Funkstation ist dann benachbart zu einer anderen Funkstation, wenn sie sich aktuell in einem Funkabdeckungsbereich dieser anderen Funkstation befindet. Relevant für die Überprüfung, ob zwei Funkstationen benachbarte Funkstationen darstellen, ist der Funkabdeckungsbereich, der sich auf die Kommunikation zwischen diesen beiden Funkstationen bezieht. Eine Mobilstation ist z.B. dann benachbart zu einer anderen Mobilstation, wenn sie sich aktuell innerhalb eines zur Kommunikation mit Mobilstationen eingesetzten Funkabdeckungsbereichs der anderen Mobilstation befindet. Eine Funkstation innerhalb des betrachteten Funkkommunikationssystems kann eine beliebige Anzahl von benachbarten Funkstationen aufweisen.The radio communication system can contain both mobile and stationary radio stations. Examples of mobile radio stations are mobile stations or laptops, examples of stationary radio stations are base stations, radio access points or stationary computers with a radio connection. These radio stations can communicate with each other. It is possible that radio stations for communication with other radio stations have different types of radio interfaces with different radio coverage areas. For example, a mobile station may have a different radio coverage area for communication with a base station than for communication with another mobile station. A radio station is adjacent to another radio station if it is currently in a radio coverage area of this other Radio station is located. The radio coverage area, which relates to the communication between these two radio stations, is relevant for checking whether two radio stations represent adjacent radio stations. A mobile station is, for example, adjacent to another mobile station if it is currently within a radio coverage area of the other mobile station used for communication with mobile stations. A radio station within the radio communication system under consideration can have any number of neighboring radio stations.
In dem Funkkommunikationssystem sind Informationen von einer ersten Funkstation zu einer zweiten Funkstation übertragbar. Sind diese beiden Funkstationen benachbarte Funkstationen, so kann die Übertragung von Informationen direkt stattfinden.Information can be transmitted in the radio communication system from a first radio station to a second radio station. If these two radio stations are adjacent radio stations, the transmission of information can take place directly.
Sind die beiden Funkstationen jedoch nicht benachbart, so ist die Weiterleitung der Informationen durch andere Funkstationen nötig. Die Informationen können dann von einer oder mehreren anderen Funkstationen empfangen und weitergeleitet wer- den. Hierzu tragen die Informationen eine Identifikationsinformation der zweiten Funkstation. Die Weiterleitung erfolgt gemäß obiger Erklärung jeweils über benachbarte Funkstationen. Eine Weiterleitung ist sowohl ausschließlich über gleichartige Funkstationen, wie zum Beispiel gleichartige Mo- bilstationen, möglich, als auch über verschiedenartige Funkstationen, wie zum Beispiel Mobilstationen und Basisstationen.However, if the two radio stations are not adjacent, the information must be forwarded by other radio stations. The information can then be received and forwarded by one or more other radio stations. For this purpose, the information carries identification information from the second radio station. The forwarding takes place in accordance with the above explanation in each case via neighboring radio stations. Forwarding is only possible via radio stations of the same type, such as mobile stations of the same type, and via radio stations of different types, such as mobile stations and base stations.
Die Informationen werden in dem Funkkommunikationssystem über einen Pfad übertragen. Dieser Pfad besteht an erster Stelle aus der ersten, die Informationen zuerst ausstrahlenden Funkstation, dann aus der oder den die Informationen weiterleitenden Funkstation, sowie an letzter Stelle aus der zweiten, die Informationen letztendlich empfangenden Funkstation.The information is transmitted in the radio communication system via a path. This path consists first of all of the first radio station, which emits the information first, then of the radio station or stations transmitting the information, and, lastly, of the second radio station which ultimately receives the information.
Zur Ermittlung eines Pfades sendet die erste und die zweite Funkstation eine Nachricht aus - Diese Nachricht wird insbe- sondere jeweils per Rundsenderuf (Broadcast) an alle Nachbarn der diese Nachricht aussendenden Funkstationen gesendet. Um einen Pfad durch das Funkkommunikationssystem ermitteln zu können, trägt die ausgesendete Nachricht eine Identifikati- onsinformation der jeweils anderen Funkstation. Die von der ersten Funkstation ausgesendete Nachricht zur Ermittlung von mindestens einem Pfad trägt somit eine Identifikationsinformation von der zweiten Funkstation, und die von der zweiten Funkstation ausgesendeten Nachricht trägt eine Identifikati- onsinformation der ersten Funkstation. Vorteilhafter Weise erfolgt die Versendung dieser beiden Nachrichten durch die erste und durch die zweite Funkstation in etwa gleichzeitig. Die Nachrichten werden von der ersten und der zweiten Funkstation ausgestrahlt, ohne dass sie unmittelbar zuvor von ei- ner benachbarten Funkstation eine ähnliche Nachricht zur Ermittlung eines Pfades zwischen der ersten und der zweiten Funkstation erhalten haben, die Nachrichten bestehen insofern nicht aus einer Weiterleitung von Nachrichten zur Ermittlung eines Pfades. Insbesondere hat keine der beiden Funkstationen die Nachricht der jeweils anderen Funkstation empfangen, bevor sie ihre eigene Nachricht sendet. Somit stoßen beide Nachrichten an verschiedenen Orten des Funkkommunikationssystems ein Verfahren zur Ermittlung desselben Pfades oder derselben Pfade durch das Funkkommunikationssystem an. Aufgrund der Ausstrahlung der Nachricht zur Ermittlung eines Pfades durch die erste und durch die zweite Funkstation handelt es sich um ein bidirektionales Vorgehen zur Pfadermittlung.In order to determine a path, the first and the second radio station send out a message. each sent in particular to all neighbors of the radio stations transmitting this message (broadcast). In order to be able to determine a path through the radio communication system, the transmitted message carries identification information of the other radio station. The message sent by the first radio station to determine at least one path thus carries identification information from the second radio station, and the message sent by the second radio station carries identification information from the first radio station. These two messages are advantageously sent approximately simultaneously by the first and by the second radio station. The messages are emitted by the first and the second radio station without having received a similar message from a neighboring radio station immediately beforehand to determine a path between the first and the second radio station, so the messages do not consist of forwarding messages to determine a path. In particular, neither of the two radio stations has received the message from the other radio station before it sends its own message. Both messages thus trigger a method for determining the same path or the same paths by the radio communication system at different locations in the radio communication system. Due to the transmission of the message for determining a path by the first and by the second radio station, it is a bidirectional procedure for determining the path.
In Weiterbildung der Erfindung werden die erste und die zwei- te Funkstation zur Versendung der jeweiligen Nachricht von einer netzseitigen Einrichtung des Funkkommunikationssystems aufgefordert. Diese Aufforderung kann über eine Funkstation erfolgen. Insbesondere kann die Aufforderung die Identifikationsinformation der jeweils anderen Funkstation enthalten. Eine derartige Aufforderung erlaubt eine Mischung aus einer zentralen, von einer netzseitigen Einrichtung gesteuerten, und einer dezentralen, von einzelnen Funkstationen durchge- führten, Ermittlung von mindestens einem Pfad zwischen der ersten und der zweiten Funkstation.In a further development of the invention, the first and the second radio station are requested to send the respective message by a network-side device of the radio communication system. This request can be made via a radio station. In particular, the request can contain the identification information of the respective other radio station. Such a request allows a mixture of a central one, controlled by a network-side device, and a decentralized one, carried out by individual radio stations. led, determination of at least one path between the first and the second radio station.
Vorzugsweise informiert die erste Funkstation vor der Auffor- derung die netzseitige Einrichtung über eine zukünftige Übermittlung von Informationen von der ersten zu der zweiten Funkstation. Die erste Funkstation kann auch vor der Aufforderung Informationen über mindestens einen Pfad zwischen der ersten und der zweiten Funkstation von der netzseitigen Ein- richtung anfordern.Before the request, the first radio station preferably informs the network device of a future transmission of information from the first to the second radio station. The first radio station can also request information about at least one path between the first and the second radio station from the network-side device before the request.
In einer Ausgestaltung der Erfindung leiten die benachbarte oder die benachbarten Funkstationen, welche die jeweilige Nachricht empfangen haben, an ihre jeweilige benachbarte oder benachbarten Funkstationen die jeweilige Nachricht nach Hinzufügen von Identifikationsinformationen weiter. Eine Funkstation, welche eine Nachricht zur Ermittlung von mindestens einem Pfad zwischen der ersten und der zweiten Funkstation empfangen hat, kann somit eine ihr eigene Identifikationsin- formation zu dieser Nachricht hinzufügen. Nach dem Hinzufügen dieser Identifikationsinformation leitet die entsprechende Funkstation die derart modifizierte Nachricht weiter. Dieses Verfahren kann für die Funkstation bzw. die Funkstationen, welche im folgenden die modifizierte Nachricht empfangen, entsprechend angewendet werden. Auf diese Weise entsteht eine Nachricht, welche eine Reihe von Identifikationsinformationen umfasst. Diese Reihe von Identifikationsinformationen entspricht dann einem Pfad durch das Funkkommunikationssystem.In one embodiment of the invention, the neighboring or neighboring radio stations which have received the respective message forward the respective message to their respective neighboring or neighboring radio stations after adding identification information. A radio station which has received a message for determining at least one path between the first and the second radio station can thus add its own identification information to this message. After adding this identification information, the corresponding radio station forwards the message modified in this way. This method can be used accordingly for the radio station or the radio stations which subsequently receive the modified message. In this way, a message is created which comprises a series of identification information. This series of identification information then corresponds to a path through the radio communication system.
Mit Vorteil überträgt eine Funkstation, welche sowohl eine Nachricht gegebenenfalls mit von einer oder mehreren Funkstationen hinzugefügten Identifikationsinformationen von der ersten Funkstation - als auch eine Nachricht gegebenenfalls mit von einer oder mehreren Funkstationen hinzugefügten Identifikationsinformationen von der zweiten Funkstation empfangen hat, Informationen über einen Pfad zwischen der ersten und der zweiten Funkstation an die erste und/oder die zweite Funkstation gegebenenfalls über eine oder mehrere weitere Funkstationen unter Verwendung der Informationen über den Pfad. Die mindestens eine Funkstation hat also zwei zusammengehörige Nachrichten von der ersten und der zweiten Funkstation, gegebenenfalls über andere Funkstationen, erhalten, welche zur Ermittlung eines Pfades zwischen der ersten und der zweiten Funkstation dienen. Dass die beiden Nachrich- ten zusammengehören, kann die mindestens eine Funkstation an einer Identifikationsinformation der Nachrichten und/oder an der Tatsache, dass beide Nachrichten zur Ermittlung eines Pfades zwischen der ersten und der zweiten Funkstation dienen, erkennen. Da diese Nachrichten die Identifikationsinfor- mationen der die Nachrichten weiterleitenden Funkstationen umfassen, ist der mindestens einen Funkstation ein Pfad durch das Funkkommunikationssystem bekannt. Informationen über diesen Pfad kann diese mindestens eine Funkstation dann an die erste und/oder an die zweite Funkstation übertragen. Für die- se Übertragung kann die mindestens eine Funkstation ihreA radio station advantageously transmits both a message from the first radio station, possibly with identification information added by one or more radio stations, and a message, if appropriate, from the second radio station with identification information added from one or more radio stations has received information about a path between the first and the second radio station to the first and / or the second radio station, possibly via one or more further radio stations, using the information about the path. The at least one radio station has thus received two related messages from the first and the second radio station, possibly via other radio stations, which are used to determine a path between the first and the second radio station. The at least one radio station can recognize that the two messages belong together from identification information of the messages and / or from the fact that both messages are used to determine a path between the first and the second radio station. Since these messages include the identification information of the radio stations that forward the messages, a path through the radio communication system is known to the at least one radio station. This at least one radio station can then transmit information about this path to the first and / or to the second radio station. The at least one radio station can be used for this transmission
Kenntnis des Pfades verwenden. Somit werden die Informationen über den Pfad zwischen der ersten und der zweiten Funkstation auf einem oder mehreren Teilen des Pfades zwischen der ersten und der zweiten Funkstation übertragen. Auf diese Weise kön- nen die erste und/oder die zweite Funkstation Kenntnis über den derart ermittelten Pfad zwischen der ersten und der zweiten Funkstation erlangen. Dieser Pfad kann dann zur Versendung von Informationen von der ersten zu der zweiten Funkstation versendet werden. Hierzu kann der Pfad in ein Kopfteil der zu übertragenden Information eingefügt werden.Use knowledge of the path. The information about the path between the first and the second radio station is thus transmitted on one or more parts of the path between the first and the second radio station. In this way, the first and / or the second radio station can gain knowledge of the path thus determined between the first and the second radio station. This path can then be sent to send information from the first to the second radio station. For this purpose, the path can be inserted into a header of the information to be transmitted.
Einer Ausgestaltung der Erfindung gemäß stellt der zu ermittelnde mindestens eine Pfad zwischen der ersten und der zweiten Funkstation - einen Teil eines Gesamtpfades zwischen der ersten Funkstation als Sendefunkstation und einer anderen als der zweiten Funkstation als Empfangs funkstation dar, oder einen Teil eines Gesamtpfades zwischen einer anderen als der ersten Funkstation als Sendefunkstation und der zweiten Funkstation als Empfangsfunkstation dar, oder einen Teil eines Gesamtpfades zwischen einer anderen als der ersten und der zweiten Funkstation und einer weiteren anderen als der ersten und der zweiten Funkstation dar. Somit kann das erfindungsgemäße Verfahren von mehreren Paaren von Funkstationen gleichzeitig eingesetzt werden, und somit ein Gesamtpfad, welcher sich aus mehreren Einzelpfaden zusa - mensetzt, ermittelt werden. Dieses Vorgehen entspricht einem multidirektionalen Verfahren zur Ermittlung eines Pfades, da das Verfahren in diesem Fall von mehr als zwei Orten des Funkkommunikationssystems in etwa gleichzeitig angestoßen werden kann.According to an embodiment of the invention, the at least one path to be determined between the first and the second radio station represents part of an overall path between the first radio station as the transmitting radio station and another radio station as the receiving radio station, or represents part of a total path between a radio station other than the first radio station as the transmitting radio station and the second radio station as the receiving radio station, or part of a total path between a radio station other than the first and the second radio station and a further other than the first and the second radio station The method according to the invention can be used simultaneously by several pairs of radio stations, and thus an overall path, which is composed of several individual paths, can be determined. This procedure corresponds to a multidirectional method for determining a path, since in this case the method can be initiated at approximately the same time from more than two locations in the radio communication system.
Die oben genannte Aufgabe wird hinsichtlich der netzseitigen Einrichtung in einem Funkkommunikationssystem durch eine netzseitige Einrichtung mit den Merkmalen des Anspruchs 7 gelöst.With regard to the network-side device in a radio communication system, the above-mentioned object is achieved by a network-side device with the features of claim 7.
Eine Ausgestaltung ist Gegenstand eines abhängigen Anspruchs,An embodiment is the subject of a dependent claim,
Erfindungsgemäß weist die netzseitige Einrichtung Mittel zum Auswählen von mindestens zwei Funkstationen aus mindestens einem Pfad zwischen der ersten und der zweiten Funkstation auf, welche zur Versendung von jeweils einer Nachricht zur Ermittlung des mindestens einen Pfades aufgefordert werden.According to the invention, the network-side device has means for selecting at least two radio stations from at least one path between the first and the second radio station, which are each requested to send a message to determine the at least one path.
Die Aufforderung an die mindestens zwei Funkstationen kann direkt von der erfindungsgemäßen netzseitigen Einrichtung durchgeführt werden, oder aber auch auf Anforderung der netzseitigen Einrichtung durch andere Funkstationen. Der zu ermittelnde Pfad ist der netzseitigen Einrichtung bei der Auswahl der mindestens zwei Funkstationen nicht bekannt. Viel- mehr legt die netzseitige Einrichtung durch die Auswahl von mindestens zwei Funkstationen Punkte des zu ermittelnden Pfades in Form der ausgewählten Funkstation fest. Diese Auswahl der mindestens zwei Funkstationen kann anhand verschiedener Kriterien erfolgen. Beispiele für Kriterien sind eine Ortsabhängigkeit der ausgewählten Funkstationen, so zum Beispiel können bevorzugt Funkstationen in der Mitte oder am Rand ei- nes geografischen Bereiches oder einer Funkzelle, oder auch aus jeder Funkzelle, durch welche der konkret zu ermittelnde Pfad verlaufen soll, mindestens eine Funkstation ausgesucht werden. Weitere Beispiele sind die Signalstärke von Funksignalen von Funkstationen oder auch ein Zufallsmechanismus zur Auswahl von Funkstationen.The request to the at least two radio stations can be carried out directly by the network-side device according to the invention, or else on request by the network-side device by other radio stations. The path to be determined is not known to the network device when selecting the at least two radio stations. Rather, the network-side device determines points of the path to be determined in the form of the selected radio station by selecting at least two radio stations. This selection the at least two radio stations can be based on different criteria. Examples of criteria are a location dependency of the selected radio stations, for example radio stations in the middle or at the edge of a geographical area or a radio cell, or also from each radio cell through which the path to be specifically determined is to run, can be at least one radio station be selected. Other examples are the signal strength of radio signals from radio stations or a random mechanism for selecting radio stations.
Bei der netzseitigen Einrichtung kann es sich z.B. um eine Basisstation oder um eine mit einer oder mehreren Basisstationen verbundenen Einrichtung handeln.In the network-side setup, it can e.g. be a base station or a device connected to one or more base stations.
In einer Ausgestaltung der Erfindung weist die netzseitige Einrichtung Mittel zum Speichern von Nachbarschaftsbeziehungen zwischen den Funkstationen des Funkkommunikationssystem auf. Hierbei kann es sich zum Beispiel um eine Tabelle han- dein, in welcher für jede Funkstation des Funkkommunikationssystems die aktuellen Nachbarfunkstationen aufgelistet sind. Die erfindungsgemäße Netzeinrichtung eignet sich insbesondere zur Durchführung des erfindungsgemäßen Verfahrens. Weitere Vorrichtungen und Mittel zur Durchführung des erfindungsgemä- ßen Verfahrens können in der netzseitigen Einrichtung vorgesehen sein.In one embodiment of the invention, the network-side device has means for storing neighborhood relationships between the radio stations of the radio communication system. This can be, for example, a table in which the current neighboring radio stations are listed for each radio station of the radio communication system. The network device according to the invention is particularly suitable for carrying out the method according to the invention. Further devices and means for carrying out the method according to the invention can be provided in the network-side device.
Im Folgenden wird die Erfindung anhand eines Ausführungsbei- spieles näher erläutert. Dabei zeigenThe invention is explained in more detail below on the basis of an exemplary embodiment. Show
Figur 1 : einen Teil eines Funkkommunikationssystems ,FIG. 1: part of a radio communication system,
Figur 2 : ein erstes Ablauf diagra m eines erfindungsgemäßen Verfahrens , Figur 3: eine schematische Illustration eines Ablaufs eines erfindungsgemäßen Verfahrens in einem Funkkommunikationssystem,FIG. 2: a first sequence diagram of a method according to the invention, FIG. 3: a schematic illustration of a sequence of a method according to the invention in a radio communication system,
Figur 4: ein zweites Ablaufdiagramm eines erfindungsgemäßen Verfahrens,FIG. 4: a second flow chart of a method according to the invention,
Figur 5a: eine erste bildliche Darstellung eines Vorteils des erfindungsgemäßen Verfahrens,FIG. 5a: a first pictorial representation of an advantage of the method according to the invention,
Figur 5b: eine zweite bildliche Darstellung eines Vorteils des erfindungsgemäßen Verfahrens .Figure 5b: a second pictorial representation of an advantage of the method according to the invention.
In Figur 1 ist ein Ausschnitt aus einem Funkkommunikations- Systems dargestellt. Dieser umfasst drei Basisstationen BSA, BSB und BSC. Weiterhin sind in dem Funkkommunikationssystem die teilneh erseitigen Funkstationen AI, A2, A3, A4, A5, Bl, B2, B3, Cl, C2, C3, C4 und C5 vorhanden. Die Funkstationen AI, A2, A3, A4 und A5 befinden sich in der Funkzelle A der Basisstation BSA. Dementsprechend halten sich die Funkstationen Bl, B2 und B3 aktuell in der Funkzelle B der Basisstation BSB und die Funkstationen Cl, C2, C3, C4 und C5 in der Funkzelle C der Basisstation BSC auf. Das Kernnetz CN enthält eine netzseitige Einrichtung NE und ist mit den Basisstationen BSA, BSB und BSC verbunden.FIG. 1 shows a section of a radio communication system. This comprises three base stations BSA, BSB and BSC. Furthermore, the subscriber-side radio stations AI, A2, A3, A4, A5, B1, B2, B3, Cl, C2, C3, C4 and C5 are present in the radio communication system. The radio stations AI, A2, A3, A4 and A5 are located in the radio cell A of the base station BSA. Accordingly, the radio stations B1, B2 and B3 are currently in the radio cell B of the base station BSB and the radio stations C1, C2, C3, C4 and C5 are in the radio cell C of the base station BSC. The core network CN contains a network-side device NE and is connected to the base stations BSA, BSB and BSC.
Im folgenden wird als Beispiel der Fall betrachtet, dass die Funkstation AI Informationen an die Funkstation Cl versenden will. Bei dem betrachteten Funkkommunikationssystem handelt es sich um eine Mischung aus einem zellularen Funkkommunikationssystem und einem funkgestützten lokalen Netz (WLAN, Wi- reless Local Area Network) . Dieser Mischungscharakter des betrachteten Funkkommunikationssystems äußert sich darin, dass einerseits zur Übermittlung von Daten zwischen den einzelnen Funkstationen diese Daten von Funkstation zu Funkstation weitergeleitet werden, und dass andererseits das Kernnetz bzw. die Basisstationen für bestimmte Funktionen benötigt werden. Zur Übermittlung der Informationen von der Funkstation AI zu der Funkstation Cl werden diese Informationen über einen Pfad von Funkstation zu Funkstation weitergeleitet. Eine Funkstation kann Informationen jeweils an eine andere Funkstation in ihrem Funkabdeckungsbereich weiterleiten. Bei Funkstationen, welche sich in ihren jeweiligen Funkabdeckungsbereichen aufhalten, handelt es sich um benachbarte Funkzellen.In the following, the case is considered as an example that the radio station AI wants to send information to the radio station C1. The radio communication system under consideration is a mixture of a cellular radio communication system and a radio-supported local area network (WLAN, Wireless Local Area Network). This mixed character of the radio communication system under consideration manifests itself in the fact that, on the one hand, this data is forwarded from radio station to radio station for the transmission of data between the individual radio stations, and that, on the other hand, the core network or the base stations are required for certain functions. To transmit the information from the radio station AI to the radio station C1, this information is forwarded via a path from radio station to radio station. A radio station can forward information to another radio station in its radio coverage area. Radio stations located in their respective radio coverage areas are neighboring radio cells.
Die Funkstationen AI, A2, A3, A4, A5, Bl, B2, B3, Cl, C2, C3, C4 und C5 weisen jeweils eine ähnliche erste Funkreichweite auf, welche deutlich kleiner als die Funkreichweite der Basisstationen BSA, BSB und BSC ist. Die Funkreichweite der Basisstationen BSA, BSB und BSC entspricht mindestens dem Radius der Funkzellen A, B und C. Neben der ersten Funkreichweite weisen die Funkstationen AI, A2, A3, A4, A5, Bl, B2, B3, Cl, C2, C3, C4 und C5 zusätzlich eine größere zweite Funkreichweite auf, aufgrund derer sie mit den Basisstationen BSA, BSB und BSC kommunizieren können. Somit stehen den Funkstationen AI, A2, A3, A4, A5, Bl, B2, B3, Cl, C2, C3, C4 und C5 zwei Funkreichweiten zur Verfügung, wobei die erste zur Kommunikation zwischen den Funkstationen AI, A2, A3, A4, A5, Bl, B2, B3, Cl, C2, C3, C4 und C5 verwendet wird, und die zweite zur Kommunikation mit den Basisstationen BSA, BSB und BSC.The radio stations AI, A2, A3, A4, A5, B1, B2, B3, Cl, C2, C3, C4 and C5 each have a similar first radio range, which is significantly smaller than the radio range of the base stations BSA, BSB and BSC. The radio range of the base stations BSA, BSB and BSC corresponds at least to the radius of the radio cells A, B and C. In addition to the first radio range, the radio stations AI, A2, A3, A4, A5, B1, B2, B3, Cl, C2, C3, C4 and C5 also have a larger second radio range, on the basis of which they can communicate with the base stations BSA, BSB and BSC. Thus, the radio stations AI, A2, A3, A4, A5, B1, B2, B3, Cl, C2, C3, C4 and C5 have two radio ranges, the first one for communication between the radio stations AI, A2, A3, A4, A5, Bl, B2, B3, Cl, C2, C3, C4 and C5 is used, and the second for communication with the base stations BSA, BSB and BSC.
Die Funkstation AI beabsichtigt nun, Informationen über andere Funkstationen zur Funkstation Cl zu senden. Hierzu muss der Funkstation AI ein Pfad durch das Funkkommunikationssystem bekannt sein. Ein Pfad könnte im betrachteten Beispiel zum Beispiel aus der folgenden Reihe von Funkstationen beste- hen: AI, A2, A3, Bl, B3, C2, C5 und Cl. Die genannten Funkstationen AI, A2, A3, Bl, B3, C2, C5 und Cl sind jeweils paarweise benachbart, so dass sie die Informationen empfangen und weiterleiten können. Damit die Informationen, welche die Funkstation AI versendet, über den ihr bekannten Pfad an die Funkstation Cl weitervermittelt werden, sind Informationen über diesen Pfad in einem Kopfteil (Header) der Informationen enthalten. Eine die Informationen empfangende Funkstation er- kennt an den Angaben über den Pfad, dass sie die Informationen den Pfad entlang weiterleiten soll. Dieses Vorgehen setzt sich solange fort, bis die Funkstation Cl anhand des Pfades oder an einer anderen Information über den Adressaten der In- formationen erkennt, dass sie der letztendliche Empfänger der Informationen ist, welcher die Informationen auswertet und nicht weiterleitet.The radio station AI now intends to send information about other radio stations to the radio station C1. For this, the radio station AI must know a path through the radio communication system. In the example under consideration, a path could consist, for example, of the following series of radio stations: AI, A2, A3, B1, B3, C2, C5 and Cl. The radio stations AI, A2, A3, B1, B3, C2, C5 and Cl mentioned are each adjacent in pairs, so that they can receive and forward the information. So that the information which the radio station AI sends is forwarded to the radio station C1 via the path known to it, information about this path is contained in a header of the information. A radio station receiving the information knows from the information about the path that it should forward the information along the path. This procedure continues until the radio station C1 uses the path or other information about the addressee of the information to recognize that it is the ultimate recipient of the information, who evaluates the information and does not forward it.
Die Funkstation AI kann zuerst in einem ihr angeschlossenen Speicher überprüfen, ob sie einen Pfad zu der Funkstation Cl kennt. Eine derartige Speicherung von Pfaden durch das Funkkommunikationssystem ist vor allem dann hilfreich, wenn das Funkkommunikationssystem eine Vielzahl von stationären, d.h. nicht mobilen, Funkstationen aufweist. Hierunter sind zum Beispiel Basisstationen zu verstehen, welche auch zur Weiterleitung der Informationen verwendet werden können. Weist das Funkkommunikationssystem hingegen eine Vielzahl von mobilen Funkstationen auf, dann verändern sich die Positionen dieser Funkstationen in der Regel mit der Zeit, so dass Pfade nach einer gewissen Zeit ihre Aktualität verlieren können. In diesem Fall kann auf die Verwendung von gespeicherten Pfadtabellen verzichtet werden, oder die Pfade der Tabellen werden nach einer zu bestimmenden Zeit automatisch gelöscht und somit nicht mehr ohne Überprüfung verwendet.The radio station AI can first check in a memory connected to it whether it knows a path to the radio station C1. Such storage of paths by the radio communication system is particularly helpful when the radio communication system has a plurality of stationary, i.e. not mobile, radio stations. This includes base stations, for example, which can also be used to forward the information. If, on the other hand, the radio communication system has a large number of mobile radio stations, the positions of these radio stations generally change over time, so that paths can lose their topicality after a certain time. In this case, the use of saved path tables can be omitted, or the paths of the tables are automatically deleted after a specified time and are therefore no longer used without checking.
Im betrachteten Beispiel wird angenommen, dass die Funkstation AI. keinen Pfad zu der Funkstation Cl kennt. Figur 2 zeigt ein erfindungsgemäßes Verfahren zur Ermittlung eines geeigneten Pfades durch das Funkkommunikationssystem der Figur 1. Zu Beginn sendet die Funkstation AI eine Nachricht DNID (Destination Node Identification) an die Basisstation BSA. Die Benachrichtigung DNID enthält eine Aufforderung an die Basisstation BSA bzw. das Kernnetz CN, zu überprüfen, ob die Funkstation Cl im Funkkommunikationssystem registriert ist. Diese Überprüfung kann im Kernnetz CN unter Verwendung von verschiedenen Tabellen oder Registern, wie z.B. einem HLR (Home Location Register) oder einem VLR (Visitor Location Register) stattfinden. Stellt das Kernnetz CN fest, dass die gewünschte Funkstation Cl aktuell nicht im Funkkommunikationssystem als Empfänger von Informationen verfügbar ist, so ( sendet die Basisstation BSA der Funkstation AI eine entsprechende Fehler- meidung. Im betrachteten Beispiel wird durch das Kernnetz CN ermittelt, dass sich die Funkstation Cl in der Funkzelle C der Basisstation BSC aufhält.In the example considered, it is assumed that the radio station AI. knows no path to the radio station C1. FIG. 2 shows a method according to the invention for determining a suitable path through the radio communication system of FIG. 1. At the beginning, the radio station AI sends a message DNID (Destination Node Identification) to the base station BSA. The notification DNID contains a request to the base station BSA or the core network CN to check whether the radio station C1 is registered in the radio communication system. This check can be carried out in the core network CN using various tables or registers, such as an HLR (Home Location Register) or a VLR (Visitor Location Register) occur. Represents the core network CN determines that the desired radio station Cl is not available in the radio communication system as a receiver of information to date, so (the base station BSA transmits the radio station AI an appropriate error avoidance. In the example considered, is determined by the core network CN that the Radio station Cl in the radio cell C of the base station BSC.
Die Basisstation BSA sendet daraufhin an die Funkstation AI eine Nachricht RDST (Route Discovery Start) , womit die Funkstation AI aufgefordert wird, durch das Aussenden einer geeigneten Broadcast Nachricht das Verfahren zur Ermittlung des Pfades zur Funkstation Cl zu initiieren. Eine entsprechende Nachricht RDST sendet auch die Basisstation BSC an die Funk- Station Cl . Durch diese Nachricht RDST wird die Funkstation Cl aufgefordert, durch das Aussenden einer Broadcast Nachricht ebenso das verfahren zur Ermittlung eines geeigneten Pfades zwischen der Funkstation Cl und Funkstation AI anzustoßen. Während der Funkstation AI aufgrund ihrer An- frage DNID der Endpunkt des gesuchten Pfades in Form derThe base station BSA then sends a message RDST (Route Discovery Start) to the radio station AI, with which the radio station AI is requested to initiate the method for determining the path to the radio station C1 by sending a suitable broadcast message. The base station BSC also sends a corresponding message RDST to the radio station C1. With this message RDST, the radio station C1 is requested to likewise initiate the procedure for determining a suitable path between the radio station C1 and the radio station AI by sending out a broadcast message. During the radio station AI based on its request DNID the end point of the searched path in the form of the
Funkstation Cl bereits bekannt ist, wird der Funkstation Cl durch die Nachricht RDST von der Basisstation BSC eine Identifikationsinformation der Funkstation AI mitgeteilt, welche für die Funkstation Cl der Endpunkt des zu ermittelnden Pfa- des darstellt.Radio station C1 is already known, the radio station C1 is informed by the RDST message from the base station BSC of identification information from the radio station AI, which for the radio station C1 represents the end point of the path to be determined.
Daraufhin sendet die Funkstation AI eine Nachricht RREQ (Route Request) aus. Diese Nachricht RREQ wird per Rundsenderuf ausgestrahlt, so dass alle Funkstationen in der Nachbarschaft der Funkstation AI durch diese Nachricht RREQ adressiert sind. Die Nachricht RREQ, welche von der Funkstation AI ausgestrahlt wird, enthält Informationen darüber, dass ein Pfad zwischen der Funkstation AI und der Funkstation Cl gesucht wird. Eine ähnliche Nachricht RREQ wird auch von der Funksta- tion Cl ausgestrahlt, diese informiert die Funkstationen darüber, dass ein Pfad zwischen der Funkstation Cl und der Funkstation AI ermittelt werden soll. Eine Nachricht RREQ kann enthalten eine Identifikationsnummer der Pfadermittlung, Informationen über eine maximale Anzahl von Funkstationen, welche der zu ermittelnde Pfad beinhalten darf und ein Feld, welches die Anzahl der Weiterleitungen der Nachricht RREQ anzeigt, sowie eine Identifikationsinformation der ersten und der zweiten Funkstation.The radio station AI then sends out a RREQ (Route Request) message. This message RREQ is broadcast via a broadcast call, so that all radio stations in the vicinity of the radio station AI are addressed by this message RREQ. The message RREQ, which is broadcast by the radio station AI, contains information that a path is sought between the radio station AI and the radio station C1. A similar message RREQ is also broadcast by the radio station C1, which informs the radio stations that a path between the radio station C1 and the radio station AI is to be determined. A message RREQ can contain an identification number of the path determination, information about a maximum number of radio stations which the path to be determined may contain and a field which indicates the number of forwardings of the message RREQ, and identification information of the first and the second radio station.
Alle Funkstationen, welche eine entsprechende Nachricht RREQ empfangen, entnehmen der Nachricht die Aufforderung, dieseAll radio stations which receive a corresponding RREQ message take the request from the message
Nachricht RREQ per Rundsenderuf weiterzuleiten. Vor der Weiterleitung der Nachricht RREQ wird durch die die Nachricht RREQ empfangende und weiterleitende Funkstation eine Identifikationsinformation derselben Funkstation an die Nachricht RREQ angehängt. Weiterhin erhöht die Funkstation vor der Weiterleitung der Nachricht RREQ das Feld mit der Anzahl der Weiterleitungen um den Wert eins. Erreicht die Anzahl der Weiterleitungen die maximale Anzahl von Funkstationen, welche der zu ermittelnde Pfad beinhalten darf - abzüglich der ers- ten und der zweiten Funkstation -, so verwirft die Funkstation die Nachricht RREQ und leitet diese nicht weiter.Forward message RREQ via broadcast call. Before the RREQ message is forwarded, identification information from the same radio station is appended to the RREQ message by the radio station receiving and transmitting the RREQ message. Furthermore, the radio station increases the field with the number of forwardings by the value one before forwarding the RREQ message. If the number of forwardings reaches the maximum number of radio stations which the path to be determined may contain - minus the first and the second radio station - the radio station rejects the RREQ message and does not forward it.
In Figur 3 ist zu erkennen, dass sich die Funkstation A5 in der Nachbarschaft der Funkstation AI befindet. Somit empfängt die Funkstation A5 die Nachricht RREQ der Funkstation AI..In Figure 3 it can be seen that the radio station A5 is in the vicinity of the radio station AI. Radio station A5 thus receives the RREQ message from radio station AI ..
Nach dem Empfang der Nachricht RREQ hängt die Funkstation A5 ihre Identifikationsinformation an die Nachricht RREQ und sendet die derart modifizierte Nachricht RREQ per Rundsenderuf aus. Die Funkstation AI empfängt im Folgenden aufgrund ihrer Nachbarschaft zu der Funkstation A5 die Nachricht RREQ, welche von der Funkstation A5 ausgestrahlt wird. Sie erkennt jedoch an der Nachricht RREQ, dass sie diese bereits selber versendet hat, und leitet die Nachricht RREQ somit nicht erneut weiter. Jede Funkstation, welche eine Nachricht RREQ empfängt, überprüft weiterhin, ob sie den gesuchten Pfad durch das Funkkommunikationssystem in einem Speicher gespeichert hat. Würde zum Beispiel die Funkstation A5 erkennen, dass sie einen Pfad zwischen der Funkstation AI und der Funkstation Cl kennt, so würde sie keine Nachricht RREQ aussenden, sondern der Funkstation AI -eine Nachricht, welche den gesuchten Pfad beinhaltet, senden.After receiving the RREQ message, the radio station A5 hangs its identification information on the RREQ message and transmits the RREQ modified message in this way by broadcasting. The radio station AI subsequently receives the message RREQ due to its proximity to the radio station A5, which is broadcast by the radio station A5. However, it recognizes from the RREQ message that it has already sent it itself and therefore does not forward the RREQ message again. Each radio station which receives a RREQ message continues to check whether it has stored the searched path through the radio communication system in a memory. For example, would recognize the radio station A5 that it knows a path between the radio station AI and the radio station C1, it would not send a message RREQ, but would send the radio station AI a message which contains the path sought.
Entsprechend empfängt auch die Funkstation C5 eine Nachricht RREQ von der Funkstation Cl, welche ihr anzeigt, dass ein Pfad zwischen der Funkstation Cl und der Funkstation AI ermittelt wird. Die Funkstation C5 prüft daraufhin, ob ihr e- ventuell aus einem Speicher ein solcher Pfad bekannt ist. Ist dies nicht der Fall, so sendet sie eine Nachricht RREQ per Rundsenderuf aus, nachdem sie ihre Identifikationsinformation dieser beigefügt hat.Correspondingly, the radio station C5 also receives a message RREQ from the radio station C1, which indicates to it that a path between the radio station C1 and the radio station AI is being determined. The radio station C5 then checks whether such a path is possibly known to it from a memory. If this is not the case, it sends a RREQ message by broadcasting after it has added its identification information to it.
Das generelle Vorgehen zur Ermittlung eines Pfades ist dementsprechend das folgende: die beiden Funkstationen AI und Cl stoßen das Verfahren an, indem sie jeweils eine Nachricht RREQ per Rundsenderuf senden. Diese Nachricht RREQ enthält die Mitteilung, dass ein Pfad zwischen den Funkstationen AI und Cl gesucht wird. Jede benachbarte Funkstation dieser beiden Funkstationen AI und Cl, welche die Nachricht RREQ empfangen, prüfen daraufhin, ob ihnen ein solcher Pfad bekannt ist. Eine derartige Prüfung kann bei mobilen Funkkommunikationssystemen auch entfallen. Weiterhin prüft jede Funkstation, welche eine Nachricht RREQ erhalten hat, gegebenenfalls unter Verwendung einer Identifikationsnummer der Ermittlung des Pfades, ob sie diese Nachricht bereits zu einem früheren Zeitpunkt erhalten hat. Ist dies gegeben, so reagiert diese Funkstation nicht auf die Nachricht RREQ. Hat eine Funkstati- on eine derartige Nachricht RREQ jedoch nicht zu einem früheren Zeitpunkt erhalten, so hängt sie ihre Identifikationsinformation an die Nachricht RREQ und sendet die derart modifizierte Nachricht RREQ ebenso per Rundsenderuf aus. Weiterhin kann bei Verwendung einer maximalen Anzahl an Funkstationen pro Pfad auch der entsprechende Zähler von der Funkstation erhöht werden. Da die Nachricht RREQ sowohl von der Funkstation AI als auch von der Funkstation Cl gesandt wurde, erreichen Funkstationen sowohl Nachrichten RREQ von seitens der Funkstation AI, durch welche nach einem Pfad zwischen der Funkstation AI und der Funkstation Cl gesucht wird, als auch Nachrichten RREQ von seitens der Funkstation Cl, durch welche nach einem Pfad zwischen der Funkstation Cl und der Funkstation AI gesucht wird. In Figur 3 ist der Fall dargestellt, dass diese Situation zuerst auf die Funkstation B3 zutrifft. Die Funkstation B3 hat somit eine Nachricht RREQ von der Funkstation B2 erhalten, an welcher sie erkennt, dass ein Pfad zwischen der Funkstation AI und der Funkstation Cl gesucht wird, sowie eine Nachricht RREQ von der Funkstation C2, an welcher zu erkennen ist, dass ein Pfad zwischen der Funkstation Cl und Funkstation AI ge- sucht wird. Anhand der Inhalte dieser beiden Nachrichten RREQ erkennt die Funkstation B3, dass diese beiden Nachrichten RREQ sich auf denselben zu ermittelnden Pfad beziehen. Die Nachricht RREQ von der Funkstation B2 enthält Identifikationsinformationen über die Funkstationen AI, A5 und B2. Demge- mäss enthält die Nachricht RREQ von der Funkstation C2 Iden- tifikationsinformationen über die Funkstation Cl, C5 und C2. Somit ist der Funkstation B3 nach dem Empfang der beiden Nachrichten RREQ ein Pfad zwischen den Funkstationen AI und Cl bekannt. Wie in Figur 2 zu erkennen ist, sendet daraufhin - die Funkstation B3 eine Nachricht RREP (Route Reply) an die Funkstationen C2 und B2. Diese Nachrichten RREP werden nicht per Rundsenderuf versendet, sondern unter Verwendung eines Einzelsenderuf. Hierzu setzt die Funkstation B3 die Kenntnis des Pfades zwischen den Funkstationen AI und Cl ein. Die Nachrichten RREP enthalten Informationen über den Pfad zwischen den Funkstationen AI und Cl . Diese Informationen werden von den Funkstationen gemäß der Reihenfolge des Pfades zwischen den Funkstationen AI und Cl bis zu der Sendefunkstation AI und bis der Empfangsstation Cl weitergeleitet. Hierbei kann der zur Weiterleitung zu verwendende Pfad in einen Kopfteil der Nachrichten RREP eingefügt sein. Die Funkstation B2 erkennt dann zum Beispiel, dass nach ihrer Identifikationsin- formation die Identifikationsinformation der Funkstation A5 folgt, so dass sie eine Nachricht RREP an die Funkstation A5 sendet.Accordingly, the general procedure for determining a path is as follows: the two radio stations AI and Cl initiate the procedure by sending a RREQ message by broadcasting. This message RREQ contains the message that a path is sought between the radio stations AI and Cl. Each neighboring radio station of these two radio stations AI and Cl, which receive the RREQ message, then check whether they know such a path. Such a test can also be omitted in the case of mobile radio communication systems. Furthermore, each radio station that has received a RREQ message checks, if necessary using an identification number for determining the path, whether it has already received this message at an earlier point in time. If this is the case, this radio station does not respond to the RREQ message. However, if a radio station has not received such a message RREQ at an earlier point in time, it attaches its identification information to the message RREQ and also sends the message RREQ modified in this way by broadcasting. Furthermore, if a maximum number of radio stations per path is used, the corresponding counter can also be increased by the radio station. Since the message RREQ was sent both by the radio station AI and by the radio station C1, radio stations reach both messages RREQ from the side of the radio station AI, through which a path between the radio station AI and the radio station Cl is searched, and messages RREQ from on the part of the radio station Cl, through which a path between the radio station Cl and the radio station AI is searched. FIG. 3 shows the case in which this situation first applies to the radio station B3. The radio station B3 has thus received a message RREQ from the radio station B2, which it uses to recognize that a path between the radio station AI and the radio station C1 is being sought, and a message RREQ from the radio station C2, which can be used to recognize that a Path between radio station Cl and radio station AI is searched. Based on the contents of these two messages RREQ, the radio station B3 recognizes that these two messages RREQ relate to the same path to be determined. The RREQ message from the radio station B2 contains identification information about the radio stations AI, A5 and B2. Accordingly, the RREQ message from the radio station C2 contains identification information about the radio stations C1, C5 and C2. The radio station B3 thus knows a path between the radio stations AI and Cl after receiving the two messages RREQ. As can be seen in FIG. 2, the radio station B3 then sends a message RREP (Route Reply) to the radio stations C2 and B2. These RREP messages are not sent by broadcast call, but by using a single send call. For this purpose, the radio station B3 uses the knowledge of the path between the radio stations AI and Cl. The RREP messages contain information about the path between the radio stations AI and Cl. This information is forwarded by the radio stations in accordance with the sequence of the path between the radio stations AI and Cl to the transmitting radio station AI and to the receiving station Cl. The path to be used for forwarding can be inserted in a header of the messages RREP. The radio station B2 then recognizes, for example, that after its identification formation follows the identification information of the radio station A5, so that it sends a message RREP to the radio station A5.
Die Informationen über den Pfad zwischen der Funkstation AI und der Funkstation Cl, welche die Funkstation B3 unter Verwendung der Nachrichten RREP aussendet, können auch lediglich an die Funkstation AI zurückgesendet werden. In diesem Fall hat die Funkstation Cl, die zwar das Verfahren zur Ermittlung des Pfades angestoßen hat, keine Kenntnis von dem ermittelten Pfad zwischen den Funkstationen AI und Cl . Da jedoch die Funkstation AI Informationen INFO zu der Funkstation Cl versenden will, reicht es aus, wenn nur diese den ermittelten Pfad zwischen den Funkstationen AI und Cl kennt. Es ist auch möglich, dass die Informationen über den Pfad, welchen die Funkstation B3 mittels der Nachrichten RREP ausstrahlt, nur einen Teil des Pfades betreffen. So kann die Funkstation B3 ausschließlich den Teilpfad zwischen der Funkstation AI und der Funkstation B3 an die Funkstation AI übermitteln. Zur Versendung der Informationen INFO von der Funkstation AI zu der Funkstation Cl versendet die Funkstation AI dann zuerst über den ihr bekannten Teilpfad, woraufhin die Funkstation B3 für den zweiten Teil des Pfades zwischen der Funkstation B3 und der Funkstation Cl den entsprechenden Teilpfad in den Header der Informationen einfügt. a< <The information about the path between the radio station AI and the radio station C1, which the radio station B3 sends out using the messages RREP, can also only be sent back to the radio station AI. In this case, the radio station Cl, which has initiated the method for determining the path, has no knowledge of the determined path between the radio stations AI and Cl. However, since the radio station AI wants to send information INFO to the radio station Cl, it is sufficient if only this knows the determined path between the radio stations AI and Cl. It is also possible for the information about the path which the radio station B3 emits by means of the messages RREP to relate only to part of the path. Thus, the radio station B3 can only transmit the partial path between the radio station AI and the radio station B3 to the radio station AI. To send the information INFO from the radio station AI to the radio station Cl, the radio station AI then first sends via the part path known to it, whereupon the radio station B3 for the second part of the path between the radio station B3 and the radio station Cl sends the corresponding part path into the header of Inserts information. a <<
In der Regel werden unter Verwendung des erfindungsgemäßen.., Verfahrens mehrere Pfade durch das Funkkommunikationssystem ermittelt. Dies führt dazu, dass der Funkstation AI mehrere Pfade zur Versendung der Informationen INFO an die Funkstation Cl zur Verfügung stehen. Die Funkstation AI kann dann eine geeignete Auswahl aus diesen Pfaden treffen, um die Informationen INFO an die Funkstation Cl zu versenden, oder sie kann mehrere Pfade zur Versendung der Informationen INFO an die Funkstation Cl verwenden. Im bisher beschriebenen Verfahren handelt es sich bei den beiden Funkstationen AI und Cl, welche das Verfahren zur Ermittlung des Pfades durch die Versendung einer Nachricht anstoßen, um die die Information zuerst sendende und die die Information letztendlich empfangende Funkstation. Bei demAs a rule, several paths through the radio communication system are determined using the inventive method. This means that the radio station AI has several paths available for sending the information INFO to the radio station C1. The radio station AI can then make a suitable selection from these paths in order to send the information INFO to the radio station C1, or it can use several paths to send the information INFO to the radio station C1. In the method described so far, the two radio stations AI and C1 are used, which are the method for determining the path by sending a message the radio station that sends the information first and the radio station that ultimately receives the information. In which
Pfad zwischen diesen beiden Funkstationen handelt es sich somit um den Gesamtpfad, über den die Informationen zu versenden sind. Es ist jedoch auch möglich, dass der zu ermittelnde Pfad nur ein Teilpfad eines Gesamtpfades, über den Informati- onen versendet werden sollen, darstellt. Dies kann dadurch realisiert werden, dass die netzseitige Einrichtung mehrere Funkstationen anweist, eine entsprechende Nachricht RREQ zur Ermittlung eines Pfades durch das Funkkommunikationssystem auszusenden. In Figur 4 ist der Fall dargestellt, dass die netzseitige Einrichtung NE der Figur 1 nach Empfang einer Nachricht DNID von der Funkstation AI den Funkstationen AI, B2 und Cl eine Nachricht RDST sendet. Diese Versendung erfolgt für die Funkstation AI unter Verwendung der Basisstation BSA, für die Funkstation B2 unter Verwendung der Basissta- tion BSB und für die Funkstation Cl unter Verwendung der Basisstation BSC. In den Nachrichten RDST werden die adressierten Funkstationen aufgeforderte Nachrichten RREQ zur Ermittlung eines Pfades durch das Funkkommunikationssystems per Rundsenderuf auszustrahlen. Die Nachricht RDST an die Funk- Station AI beinhaltet die Anweisung, einen Pfad zwischen der Funkstation AI und der Funkstation B2 zu ermitteln. Die Anweisung RDST an die Funkstation B2 enthält die Anweisung, sowohl einen Pfad zwischen der Funkstation B2 und der Funkstation AI, als auch einen Pfad zwischen der Funkstation B2 und der Funkstation Cl zu ermitteln. Entsprechend beinhaltet die Nachricht RDST an die Funkstation Cl die Anweisung, einen Pfad zwischen der Funkstation Cl und der Funkstation B2 zu ermitteln. Diese jeweiligen Informationen sind dann von den Funkstationen AI, B2 und Cl den von ihnen ausgestrahlten Nachrichten RREQ beizufügen. Die Funkstationen AI, B2 und Cl werden von der netzseitigen Einrichtung NE unter Verwendung von Mitteln Ml zur Auswahl von Funkstationen ausgewählt. Hierzu ist es vorteilhaft, dass die netzseitige Einrichtung NE die aktuelle Topologie, d.h. die Nachbarschaftsbeziehung zwischen den verschiedenen Funkstationen, kennt. Ein Verfahren zur Ermittlung der Topologie des Netzwerkes kann zum Beispiel folgendermaßen aussehen: jede Funkstation sendet in regelmäßigen Zeitabständen ein Broadcast Signal, in welchen es die jeweiligen Nachbarfunk- Stationen auffordert, eine Antwort zu senden. Nach Empfang einer derartigen Antwort von ihrer oder ihren benachbarten Funkstationen ist der entsprechenden Funkstation bekannt, welche Funkstationen sich in ihrer Nachbarschaft aktuell befinden. Diese Informationen sendet die Funkstation dann über die entsprechende Basisstation an die netzseitige Einrichtung NE . Führen alle Funkstationen des Funkkommunikationssystems ein derartiges Verfahren zur Ermittlung der aktuellen Topologie des Netzwerkes durch, so ist der netzseitigen Einrichtung NE die gesamte Topologie des Netzwerkes bekannt. Vorteilhaft- erweise wird das Verfahren mehrmals, so z.B. zu periodisch wiederkehrenden Zeitpunkten, durchgeführt, um der Mobilität und der Verfügbarkeit von Funkstationen Rechnung zu tragen. Diese Topologie kann in der netzseitigen Einrichtung NE unter Verwendung von Mitteln M2 zur Speicherung von Nachbarschafts- beziehungen gespeichert -werden .The path between these two radio stations is therefore the total path via which the information is to be sent. However, it is also possible for the path to be determined to represent only a partial path of an overall path via which information is to be sent. This can be achieved in that the network-side device instructs a plurality of radio stations to send out a corresponding RREQ message to determine a path through the radio communication system. FIG. 4 shows the case in which the network-side device NE of FIG. 1 sends a message RDST to the radio stations AI, B2 and Cl after receiving a message DNID from the radio station AI. This transmission takes place for the radio station AI using the base station BSA, for the radio station B2 using the base station BSB and for the radio station C1 using the base station BSC. In the RDST messages, the addressed radio stations are asked to transmit messages RREQ to determine a path through the radio communication system by broadcasting. The RDST message to the radio station AI contains the instruction to determine a path between the radio station AI and the radio station B2. The instruction RDST to the radio station B2 contains the instruction to determine both a path between the radio station B2 and the radio station AI and also a path between the radio station B2 and the radio station C1. Correspondingly, the RDST message to the radio station C1 contains the instruction to determine a path between the radio station C1 and the radio station B2. This respective information is then to be added by the radio stations AI, B2 and Cl to the messages RREQ they broadcast. The radio stations AI, B2 and Cl are selected by the network-side device NE using means Ml for selecting radio stations. For this purpose, it is advantageous that the network-side device NE knows the current topology, ie the neighborhood relationship between the different radio stations. A method for determining the topology of the network can, for example, be as follows: each radio station sends a broadcast signal at regular intervals, in which it requests the respective neighboring radio stations to send a response. After receiving such a response from its or its neighboring radio stations, the corresponding radio station knows which radio stations are currently in its neighborhood. The radio station then sends this information to the network-side device NE via the corresponding base station. If all radio stations of the radio communication system carry out such a method for determining the current topology of the network, the network-side device NE knows the entire topology of the network. The method is advantageously carried out several times, for example at periodically recurring times, in order to take into account the mobility and the availability of radio stations. This topology can be stored in the network-side device NE using means M2 for storing neighborhood relationships.
In Figur 4 ist zu erkennen, dass die Funkstationen AI, B2 und Cl nach Empfang der Nachricht RDST jeweils eine Nachricht RREQ zur Ermittlung des entsprechenden Pfades aussenden. Das Verfahren zur Ermittlung der Teilpfade zwischen den Funkstationen AI und B2, sowie zwischen den Funkstationen B2 und Cl verläuft analog zur obigen Beschreibung der Ermittlung des Pfades zwischen den Funkstationen AI und Bl . Gemäß Figur 4 hat die Funkstation A5 sowohl eine Nachricht zur Ermittlung des Pfades zwischen den Funkstationen AI und B2 von der Funkstation AI, als auch von Funkstation B2 empfangen. Daraufhin sendet sie eine entsprechende Mitteilung RREP mit Informatio- nen über den ermittelten Pfad an die Funkstationen AI und B2. Für diese Versendung der Informationen über den Pfad mittels der Nachricht RREP gilt die Beschreibung bezüglich dieses Signals RREP gemäß obiger Ausführung entsprechend. Auch die Funkstation C2 hat sowohl ein Signal von seitens der Funkstation Cl zur Ermittlung eines Pfades zwischen den Funkstationen Cl und B2 empfangen, als auch eine Nachricht RREQ von seitens der Funkstation B2 zur Ermittlung eines Pfades zwischen den Funkstationen B2 und Cl . Daraufhin sendet sie In- formationen über den ermittelten Pfad zwischen den Funkstationen B2 und Cl unter Verwendung der Kenntnis dieses Pfades per Einzelsenderuf über die Funkstationen C5 und B3 an die Funkstationen B2 und Cl zurück. Die Funkstation B2 kann diese Informationen über den Pfad weiterhin an die Funkstation AI weiterleiten. Die Versendung von Informationen von der Funkstation AI zur Funkstation Cl ist jedoch auch ohne diese Weiterleitung des Teilpfades an die Funkstation AI möglich.It can be seen in FIG. 4 that the radio stations AI, B2 and C1 each send a message RREQ to determine the corresponding path after receiving the message RDST. The method for determining the partial paths between the radio stations AI and B2 and between the radio stations B2 and C1 is analogous to the above description of the determination of the path between the radio stations AI and B1. According to FIG. 4, the radio station A5 received a message for determining the path between the radio stations AI and B2 from the radio station AI and from the radio station B2. Thereupon it sends a corresponding message RREP with information via the determined path to the radio stations AI and B2. For this transmission of the information about the path by means of the message RREP, the description regarding this signal RREP applies accordingly in accordance with the above description. The radio station C2 also received a signal from the radio station C1 to determine a path between the radio stations C1 and B2, and a message RREQ from the radio station B2 to determine a path between the radio stations B2 and Cl. Thereupon, it sends information about the determined path between the radio stations B2 and C1 using the knowledge of this path via individual radio calls to the radio stations B2 and C1 via the radio stations C5 and B3. The radio station B2 can continue to forward this information to the radio station AI via the path. However, the sending of information from the radio station AI to the radio station Cl is also possible without this forwarding of the partial path to the radio station AI.
Schließlich kann die Funkstation AI die Informationen INFO unter Kenntnis des Pfades über die Funkstationen A5, B2, B3, C2 und C5 an die Funkstation Cl versenden. Auch bei diesem Vorgehen ist es möglich, dass mehrere Pfade zwische der Funkstation AI und der Funkstation Cl ermittelt werden. Jeder dieser Pfade beinhaltet jedoch die Funkstation B2. Diese Tat- sache erweist sich jedoch dann als problematisch, wenn dieFinally, the radio station AI can send the information INFO to the radio station C1 knowing the path via the radio stations A5, B2, B3, C2 and C5. With this procedure it is also possible that several paths between the radio station AI and the radio station Cl are determined. However, each of these paths contains the radio station B2. However, this fact proves to be problematic if the
Funkstation B2 zur Weiterleitung der Informationen INFO aus- fällt. Um eine derartiges Ausfallrisiko z.u verringern, kann die netzseitige Einrichtung NE mehrere Funkstationen zwischen der sendenden Funkstation AI und der empfangenden Funkstation Cl zur Aussendung einer Nachricht RREQ zur Ermittlung einesRadio station B2 for forwarding the information INFO fails. In order to reduce such a risk of failure, the network-side device NE can transmit a plurality of radio stations between the transmitting radio station AI and the receiving radio station C1 in order to transmit a message RREQ to determine a
Pfades auffordern. So könnte zum Beispiel eine Nachricht RDST mit der Aufforderung zur Aussendung einer Nachricht RREQ außer an die Funkstationen AI, B2 und Cl auch an die Funkstation Bl ergehen. Die Funkstation Bl würde dann mit der Nach- rieht RDST angewiesen, einen Pfad zwischen der Funkstation Bl und der Funkstation AI zu ermitteln, sowie einen Pfad zwischen der Funkstation Bl und Funkstation Cl zu ermitteln. Weiterhin würde die Funkstation AI mit der Nachricht RDST angewiesen, einen Pfad zwischen der Funkstation AI und der Funkstation B2, als auch ein Pfad zwischen der Funkstation AI und der Funkstation Bl zu ermitteln. Entsprechend würde die Funkstation Cl aufgefordert, einen Pfad zwischen der Funkstation Cl und der Funkstation B2, als auch einen Pfad zwischen der Funkstation Cl und der Funkstation Bl zu ermitteln. In diesem Fall würden also mindestens zwei Pfade durch das Funkkommunikationssystem ermittelt werden, wobei mindestens ein Pfad die Funkstation B2 enthält und mindestens ein weiterer Pfad die Funkstation Bl enthält.Prompt path. For example, a message RDST with the request to send a message RREQ could be sent to the radio station B1 in addition to the radio stations AI, B2 and C1. The radio station B1 would then be instructed with the RDST message to determine a path between the radio station B1 and the radio station AI and to determine a path between the radio station B1 and radio station C1. Furthermore, the radio station AI would be instructed with the message RDST to determine a path between the radio station AI and the radio station B2, as well as a path between the radio station AI and the radio station B1. Correspondingly, the radio station C1 would be asked to determine a path between the radio station C1 and the radio station B2, as well as a path between the radio station C1 and the radio station B1. In this case, at least two paths would be determined by the radio communication system, at least one path containing the radio station B2 and at least one further path containing the radio station B1.
Es ist auch möglich, dass eine Basisstation von der netzseitigen Einrichtung aufgefordert wird, eine Nachricht zur Er- mittlung eines Teilpfades zu versenden. In diesem Fall kann die betroffene Basisstation die ihr übermittelte Information über Teilpfade an die netzseitige Einrichtung senden. Diese kann die betreffenden Information an die Funkstation AI über die Basisstation BSA übermitteln oder diese ausschließlich zur Aktualisierung von in der netzseitigen Einrichtung gespeicherten Verfügbarkeiten von Funkstationen innerhalb des Funkkommunikationssystems verwenden .It is also possible for the base device to request a base station to send a message to determine a partial path. In this case, the base station concerned can send the information transmitted to it via partial paths to the network-side device. The latter can transmit the relevant information to the radio station AI via the base station BSA or use it exclusively for updating the availabilities of radio stations within the radio communication system stored in the network-side device.
Das beschriebene erfindungsgemäße Verfahren weist den Vorteil auf, dass die Anzahl an Signalisierungsnachrichten zur Ermittlung eines Pfades durch das Funkkommunikationssystem im Vergleich zu herkömmlichen nicht bidirektionellen Verfahren deutlich reduziert werden kann. Dies ist schematisch in den Figuren 5a und 5b veranschaulicht. Würde ausschließlich die Funkstation AI beginnen, Nachrichten zur Ermittlung eines Pfades zur Funkstation Cl per Rundsenderuf auszusenden, so stellt der Kreis der Figur 5a den Bereich des Funkkommunikationssystem dar, innerhalb welchem von den Funkstationen des Funkkommunikationssystems Nachrichten per Rundsenderuf zur Ermittlung eines Pfades ausgesendet werden müssten. Senden hingegen sowohl die Funkstation AI, als die Funkstation Cl gemäß dem erfindungsgemäßen Verfahren eine derartige Nach- rieht zur Ermittlung eines Pfades durch das Funkkommunikationssystem aus, so ist in Figur 5b durch die Fläche der beiden Kreise gezeigt, innerhalb welcher Bereiche des Eunkkommunika- tionssystems entsprechende Nachrichten zur Ermittlung eines Pfades von den Funkstationen ausgesendet werden müssen. Es ist durch Vergleich der Figuren 5a und 5b zu erkennen, dass die Anzahl an Signalisierungsnachrichten durch ein bidirekti- onelles Vorgehen zur Ermittlung eines Pfades durch das Funkkommunikationssystem deutlich reduziert wird.The described method according to the invention has the advantage that the number of signaling messages for determining a path through the radio communication system can be significantly reduced compared to conventional non-bidirectional methods. This is illustrated schematically in FIGS. 5a and 5b. If only the radio station AI began to send out messages to determine a path to the radio station C1 by radio, the circle in FIG. 5a represents the area of the radio communication system within which messages from the radio stations of the radio communication system would have to be sent by radio to determine a path. In contrast, both the radio station AI and the radio station C1 transmit such a subsequent If the radio communication system is sufficient to determine a path, the area of the two circles shows in FIG. 5b within which areas of the radio communication system corresponding messages for determining a path must be sent by the radio stations. It can be seen by comparing FIGS. 5a and 5b that the number of signaling messages is significantly reduced by a bidirectional procedure for determining a path through the radio communication system.
Ein weiterer Vorteil ist darin zu sehen, dass der Pfad zwischen der Sendefunkstation und der Empfangsfunkstation bei Verwendung des erfindungsgemäßen Verfahrens schneller gefunden werden kann als bei herkömmlichen Verfahren zur Ermitt- lung eines Pfades. Dies führt dazu, dass die Verbindung zwischen der sendenden und der empfangenden Funkstation innerhalb einer kürzeren Zeitspanne aufgebaut werden kann.Another advantage can be seen in the fact that the path between the transmitting radio station and the receiving radio station can be found faster when using the method according to the invention than with conventional methods for determining a path. As a result, the connection between the transmitting and the receiving radio station can be established within a shorter period of time.
Das erfindungsgemäße Verfahren kann für verschiedenartigste Größen von FunkkommunikationsSystemen eingesetzt werden, somit liegt Skalierbarkeit vor. Das Verfahren ist verwendbar innerhalb einer einzigen Funkzelle oder auch, wie in Figur 3 gezeigt, für eine Mehrzahl von Funkzellen. Je größer das betrachtete Funkkommunikationssystem ist, und je weiter der räumliche Abstand zwischen der sendenden und 'der empfangenden Funkstation wird, desto mehr Funkstationen sollten eine Anweisung von der netzseitigen Einrichtung empfangen, ein Verfahren zur Ermittlung eines Pfades durch das Funkkommunikationssystem durch die Aussendung geeigneter Nachrichten anzu- stoßen. The method according to the invention can be used for the most varied sizes of radio communication systems, so scalability is available. The method can be used within a single radio cell or, as shown in FIG. 3, for a plurality of radio cells. The larger the considered radio communication system is, and the farther the spacing between the transmitting and 'the receiving radio station is, the more radio stations should receive an instruction from the network-side device, to a method for determining a path through the radio communication system by transmitting appropriate messages - bump.

Claims

Patentansprüche claims
1. Verfahren-zur Ermittlung eines Pfades in einem Funkkommunikationssystem mit einer Vielzahl von zumindest teilwei- se mobilen Funkstationen (BSA, BSB, BSC, AI, A2, A3, A4, A5, Bl, B2, B3, Cl, C2, C3, C4, C5) , wobei eine Funkstation, welche sich in einem Funkabdeckungsbereich einer anderen Funkstation befindet, eine benachbarte Funkstation zu der anderen Funkstation dar- stellt, wobei im Funkkommunikationssystem von einer ersten Funkstation (AI) als Sendefunkstation zu einer zweiten Funkstation (Cl) als Empfangsfunkstation Informationen (INFO) direkt oder über eine oder mehrere andere die Informatio- nen (INFO) empfangende und weiterleitende Funkstationen1. Method for determining a path in a radio communication system with a multiplicity of at least partly mobile radio stations (BSA, BSB, BSC, AI, A2, A3, A4, A5, B1, B2, B3, Cl, C2, C3, C4, C5), a radio station located in a radio coverage area of another radio station representing an adjacent radio station to the other radio station, with in the radio communication system from a first radio station (AI) as a transmitting radio station to a second radio station (Cl) Receiving radio station information (INFO) directly or via one or more other radio stations receiving and transmitting the information (INFO)
(A5, B2, B3, C2, C5) über mindestens einen Pfad übertragbar sind, wobei ein Pfad zwischen der ersten (AI) und der zweiten (Cl) Funkstation aus einer Reihenfolge von Funkstationen (AI, A5, B2, B3, C2, C5, Cl) besteht, welche außer der ersten Funkstation (AI) und der zweiten Funkstation (Cl) gegebenenfalls die in der Reihenfolge dazwischenliegenden die Informationen (INFO) empfangenden und weiterleitenden Funkstationen (A5, B2, B3, C2, C5) beinhaltet, dadu ch *g ekennzeichnet, dass zur Ermittlung von mindestens einem Pfad zwischen der ersten (AI) und der zweiten (Cl) Funkstation sowohl die erste (AI) als auch die zweite (Cl) Funkstation jeweils an ihre benachbarte oder benachbarten Funkstationen (A5, C5) eine Nachricht (RREQ) mit Identifikationsinformation von der jeweils anderen Funkstation (AI, Cl) sendet, wobei die zweite Funkstation (Cl) die Nachricht (RREQ) der ersten Funkstation (AI) nicht empfängt, bevor sie die Nachricht (RREQ) mit Identifikationsinformation von der ersten Funkstation (AI) sendet. (A5, B2, B3, C2, C5) can be transmitted via at least one path, wherein a path between the first (AI) and the second (Cl) radio station from a sequence of radio stations (AI, A5, B2, B3, C2, C5, Cl) which, in addition to the first radio station (AI) and the second radio station (Cl), contains the radio stations (A5, B2, B3, C2, C5) that receive and forward the information (INFO) in between, if necessary ch * g indicates that in order to determine at least one path between the first (AI) and the second (Cl) radio station, both the first (AI) and the second (Cl) radio station each send to their neighboring or neighboring radio stations (A5, C5 ) sends a message (RREQ) with identification information from the other radio station (AI, Cl), the second radio station (Cl) not receiving the message (RREQ) from the first radio station (AI) before it receives the message (RREQ) with identification information from the first foot nkstation (AI) sends.
2. Verfahren nach Anspruch 1, dadurch gekennzeichnet,2. The method according to claim 1, characterized in that
•dass die erste (All und die zweite (Cl) Funkstation zur Versendung der jeweiligen Nachricht (RREQ) von einer netzseitigen Einrichtung (NE) des Funkkommunikationssystems aufgefordert werden.• that the first (All and the second (Cl) radio station are asked to send the respective message (RREQ) by a network-side device (NE) of the radio communication system.
3. Verfahren nach Anspruch 2, dadurch gekennzeichnet, dass die erste Funkstation (AI) vor der Aufforderung3. The method according to claim 2, characterized in that the first radio station (AI) before the request
- die netzseitige Einrichtung (NE) über eine zukünftige Übermittlung von Informationen (INFO) von der ersten zu der zweiten Funkstation (Cl) informiert oder - Informationen über mindestens einen Pfad zwischen der ersten (AI) und der zweiten (Cl) Funkstation von der netzseitigen Einrichtung (NE) anfordert.- The network-side device (NE) informs about a future transmission of information (INFO) from the first to the second radio station (Cl) or - Information about at least one path between the first (AI) and the second (Cl) radio station from the network side Facility (NE) requests.
4. Verfahren nach einem der Ansprüche 1 bis 3, dadurch gekennzeichnet, dass die benachbarte oder die benachbarten Funkstationen (A5, C5) , welche die jeweilige Nachricht (RREQ) empfangen haben, an ihre jeweilige benachbarte oder benachbarten Funkstationen (B2, C2) die jeweilige Nachricht (RREQ) nach Hinzufügen von. Identifikationsinformationen weiterleiten.4. The method according to any one of claims 1 to 3, characterized in that the neighboring or the neighboring radio stations (A5, C5), which have received the respective message (RREQ), to their respective neighboring or neighboring radio stations (B2, C2) respective message (RREQ) after adding. Forward identification information.
5. Verfahren nach einem Anspruch 4, dadurch gekennzeichnet, dass mindestens eine Funkstation (B3) , welche5. The method according to claim 4, characterized in that at least one radio station (B3) which
- sowohl eine Nachricht (RREQ) gegebenenfalls mit von einer oder mehreren Funkstationen (A5, B2) hinzugefügten I- dentifikationsinformationen von der ersten Funkstation- Both a message (RREQ) from the first radio station, optionally with identification information added by one or more radio stations (A5, B2)
(AI) - als auch eine Nachricht (RREQ) gegebenenfalls mit von einer oder mehreren Funkstationen (C5, C2) hinzugefügten Identifikationsinformationen von der zweiten Funkstation (Cl) empfangen hat,(AI) - and also a message (RREQ) from the second radio station, optionally with identification information added by one or more radio stations (C5, C2) (Cl) received
Informationen über einen Pfad zwischen der ersten (AI) •■ und der zweiten (Cl) Funkstation an die erste (AI) und/oder die zweite (Cl) Funkstation überträgt gegebenenfalls über eine oder mehrere weitere Funkstation (B2, A5, C2, C5) unter Verwendung der Informationen über den Pfad.Information about a path between the first (AI) • ■ and the second (Cl) radio station to the first (AI) and / or the second (Cl) radio station may be transmitted via one or more further radio stations (B2, A5, C2, C5 ) using the information about the path.
6. Verfahren nach einem der Ansprüche 1 bis 5, dadurch gekennzeichnet, dass der zu ermittelnde mindestens eine Pfad zwischen der ersten (AI) und der zweiten (Cl) Funkstation6. The method according to any one of claims 1 to 5, characterized in that the at least one path to be determined between the first (AI) and the second (Cl) radio station
- einen Teil eines Gesamtpfades zwischen der ersten Funkstation (AI) als Sendefunkstation und einer anderen als der zweiten Funkstation (Cl) als Empfangsfunkstation oder- Part of a total path between the first radio station (AI) as a transmitting radio station and another than the second radio station (Cl) as a receiving radio station or
- einen Teil eines Gesamtpfades zwischen einer anderen als der ersten Funkstation (AI) als Sendefunkstation und der zweiten Funkstation (Cl) als Empfangsfunkstation oder- Part of a total path between a radio station other than the first radio station (AI) as the transmitting radio station and the second radio station (Cl) as the receiving radio station or
- einen Teil eines Gesamtpfades zwischen einer anderen als der ersten (AI) und der zweiten (Cl) Funkstation und einer weiteren anderen als der ersten (AI) und der zweiten (Cl) Funkstation darstellt.represents part of an overall path between a radio station other than the first (AI) and the second (Cl) radio station and a further radio station other than the first (AI) and the second (Cl) radio station.
7. Netzseitige Einrichtung (NE) in einem Funkkommunikationssystem mit einer Vielzahl von zumindest teilweise mobilen Funkstationen (BSA, BSB, BSC, AI, A2, A3, A4, A5, Bl, B2, B3, Cl, C2, C3, C4, C5) , wobei eine Funkstation, welche sich in einem Funkabdeckungsbereich einer anderen Funkstation befindet, eine benachbarte Funkstation zu der anderen Funkstation darstellt, wobei im Funkkommunikationssystem von einer ersten Funkstation (AI) als Sendefunkstation zu einer zweiten Funkstation (Cl) als E pfangsfunkstation Informationen (INFO) direkt oder über eine oder mehrere andere die Informationen (INFO) empfangenden und weiterleitenden Funkstationen7. Network-side device (NE) in a radio communication system with a plurality of at least partially mobile radio stations (BSA, BSB, BSC, AI, A2, A3, A4, A5, B1, B2, B3, Cl, C2, C3, C4, C5 ), whereby a radio station, which is located in a radio coverage area of another radio station, represents a neighboring radio station to the other radio station, whereby in the radio communication system from a first radio station (AI) as a transmitting radio station to a second radio station (Cl) as a receiving radio station information (INFO ) directly or via one or more other radio stations receiving and forwarding the information (INFO)
(A5, B2, B3, C2, C5) über mindestens einen Pfad übertragbar sind, wobei ein Pfad zwischen der ersten (AI) und der zweiten(A5, B2, B3, C2, C5) can be transmitted via at least one path, with a path between the first (AI) and the second
(Cl) Funkstation aus einer Reihenfolge von Funkstationen(Cl) radio station from a sequence of radio stations
(AI, A5, B2, B3, C2, C5, Cl) besteht, welche außer der ersten Funkstation (AI) und der zweiten Funkstation (Cl) gegebenenfalls die in der Reihenfolge dazwischenliegenden die Informationen (INFO) empfangenden und weiterleitenden Funkstationen (A5, B2, B3, C2, C5) beinhaltet, dadurch gekennzeichnet, dass die netzseitige Einrichtung (NE) Mittel (Ml) zum Auswählen von mindestens zwei Funkstationen (AI, Cl; AI, B2, Cl) aus mindestens einem Pfad zwischen der ersten(AI, A5, B2, B3, C2, C5, Cl), which, in addition to the first radio station (AI) and the second radio station (Cl), may include the radio stations (A5, receiving and forwarding the information (INFO) in between, B2, B3, C2, C5), characterized in that the network-side device (NE) means (Ml) for selecting at least two radio stations (AI, Cl; AI, B2, Cl) from at least one path between the first
(AI) und der zweiten (Cl) Funkstation aufweist, welche zur Versendung von jeweils einer Nachricht (RREQ) zur Ermittlung des mindestens einen Pfades aufgefordert werden.(AI) and the second (Cl) radio station, which are asked to send a message (RREQ) to determine the at least one path.
Netzseitige Einrichtung (NE) nach Anspruch 7, dadurch gekennzeichnet , dass die netzseitige Einrichtung (NE) Mittel (M2) zum Speichern von Nachbarschaftsbeziehungen zwischen den Funkstationen (BSA, BSB, BSC, AI, A2, A3, A4, A5, Bl, B2, B3, Cl, C2, C3, C4, C5) des FunkkommunikationsSystems aufweist. Network-side device (NE) according to claim 7, characterized in that the network-side device (NE) means (M2) for storing neighborhood relationships between the radio stations (BSA, BSB, BSC, AI, A2, A3, A4, A5, B1, B2 , B3, Cl, C2, C3, C4, C5) of the radio communication system.
EP04707927A 2003-03-11 2004-02-04 Method and network-side facility for determining a path in a radio communications system Withdrawn EP1602205A1 (en)

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PCT/EP2004/001063 WO2004082223A1 (en) 2003-03-11 2004-02-04 Method and network-side facility for determining a path in a radio communications system
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Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7466984B2 (en) * 2004-02-19 2008-12-16 Research In Motion Limited Apparatus, and associated method, for improvement in facilitating routing of data by a mobile node operable in a packet radio communication system
JP4593349B2 (en) * 2005-04-21 2010-12-08 株式会社日立製作所 Wireless communication system, wireless communication terminal, and narrow area wireless communication server
US7298714B2 (en) * 2005-10-04 2007-11-20 Yahoo! Inc. Peer-to-peer message chaining for initiating a data exchange with a server
KR20100136542A (en) * 2008-04-09 2010-12-28 어플라이드 머티어리얼스, 인코포레이티드 Simplified back contact for polysilicon emitter solar cells
US8175596B1 (en) 2008-07-10 2012-05-08 Clearwire Ip Holdings Llc System and method of extending base station coverage

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5987011A (en) * 1996-08-30 1999-11-16 Chai-Keong Toh Routing method for Ad-Hoc mobile networks
EP1263173A1 (en) * 2001-05-31 2002-12-04 Agilent Technologies, Inc. (a Delaware corporation) An adaptive path discovery process for routing data packets in a multinode network

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5613206A (en) * 1995-04-06 1997-03-18 International Business Machines Corporation Ad Hoc packet data networks using cellular telephone networks
US7002933B1 (en) * 2000-10-06 2006-02-21 Mitsubishi Electric Research Laboratories, Inc. Wireless mobile network with an adaptive locally linked mobile network for locally routing multimedia content
US6904055B2 (en) * 2002-06-24 2005-06-07 Nokia Corporation Ad hoc networking of terminals aided by a cellular network
US7280481B2 (en) * 2002-10-10 2007-10-09 Guangyi David Rong Shortest path search method “Midway”
US7466665B2 (en) * 2003-06-25 2008-12-16 Motorola, Inc. Method and apparatus for route discovery within a communication system

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5987011A (en) * 1996-08-30 1999-11-16 Chai-Keong Toh Routing method for Ad-Hoc mobile networks
EP1263173A1 (en) * 2001-05-31 2002-12-04 Agilent Technologies, Inc. (a Delaware corporation) An adaptive path discovery process for routing data packets in a multinode network

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See also references of WO2004082223A1 *

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