CA2330845A1 - Allocation of channels for packet data services - Google Patents
Allocation of channels for packet data services Download PDFInfo
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- CA2330845A1 CA2330845A1 CA002330845A CA2330845A CA2330845A1 CA 2330845 A1 CA2330845 A1 CA 2330845A1 CA 002330845 A CA002330845 A CA 002330845A CA 2330845 A CA2330845 A CA 2330845A CA 2330845 A1 CA2330845 A1 CA 2330845A1
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04W—WIRELESS COMMUNICATION NETWORKS
- H04W72/00—Local resource management
- H04W72/50—Allocation or scheduling criteria for wireless resources
- H04W72/56—Allocation or scheduling criteria for wireless resources based on priority criteria
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04W—WIRELESS COMMUNICATION NETWORKS
- H04W76/00—Connection management
- H04W76/30—Connection release
- H04W76/34—Selective release of ongoing connections
- H04W76/36—Selective release of ongoing connections for reassigning the resources associated with the released connections
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04W—WIRELESS COMMUNICATION NETWORKS
- H04W88/00—Devices specially adapted for wireless communication networks, e.g. terminals, base stations or access point devices
- H04W88/12—Access point controller devices
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Abstract
A telecommunications system (18) comprises a control node (24) and a base station node (22). The control node (24) maintains a first list (42) of idle radio channels which is consulted in order to obtain channels for a first type of telecommunications service. A second list (56) of idle radio channels is maintained for a specialized telecommunications service, the idle radio channels of the second list being radio channels which are unallocated with respect to the specialized telecommunications service but yet activated (e.g., having an established transmission path and synchronization). The second list of idle radio channels is initially consulted in order to obtain channels for the specialized telecommunications service. If no channels are available for the specialized telecommunications service on the second list, idle channels from the first list are adapted and utilized for the specialized telecommunications service. The specialized telecommunications service preferably involves packet data transfer (e.g., GPRS).
Description
ALLOCATION O~F CHANNELS FOR PACKET DATA
SERVICES
BACKGROUND
s 1. FIELD OF THE INVENTION
The present invention ;pertains to cellular telecommunications, and particularly to allocation of radio channels for data services.
SERVICES
BACKGROUND
s 1. FIELD OF THE INVENTION
The present invention ;pertains to cellular telecommunications, and particularly to allocation of radio channels for data services.
2. RELATED ART :AND OTHER CONSIDERATIONS
In recent years cellular telephones have become increasingly popular. A
cellular to telephone is just one example of what is referred to in telephone parlance as a "mobile station" or "mobile terminal". Telecommunications services are provided between a cellular telecommunications network and a mobile station (e.g., cellular telephone) over an air interface, e.g., over radio frequencies. At any moment an active mobile station is communicating over the air interface with one or more base stations. The base stations :a are, in turn, managed by base station controllers {BSCs). The base station controllers are connected via control nodEa to a core teleconunun~~ations network.
Examples of control nodes include a mobile switching center (I~iSC) node for connecting to connection-oriented, circuit switched networks such as PSTN and/or ISDN, and a general packet radio service (CiPRS) node for connecting to packet-switched networks such as Internet. for example.
A mobile station can take on various forms other than a cellular telephone, including a comput~°r (e.g., a laptop computer) with mobile termination capabilities. In .some forms, n-labile stations are capable of engaging in differing types WO 9915792.1 PCT/SE99/00610 of services, or multimedia services. In other words, the mobile station can execute several differing types of pro;~rams (i.e., ''applications") which interact with the user.
Examples of these applications include Internet browsers and electronic mail programs.
Several multimedia applications may reside in the same mobile station.
One type of standardized mobile telecommunications scheme, utilized, e.g., in Europe, is the Global System for Mobile communications (GSM). GSM
includes standards which specify functions and interfaces for various types of services.
A relatively recent rata service available within the GSM system is General Packet io Radio Service (GPRS). GPRS differs from existinD data services in that GPRS
is a packet switched service instead of a circuit switched data service. Whereas (in GSM) a circuit switched data user is connected continuously to the radio network during a data call (e.g., even when not transferring data), a GPRS user is connected to the radio network only when either (:l) the mobile station desires to transmit or (?) the network has something to transmit to t:he mobile station. In other words, in GPRS the mobile station (e.g., a computer with mobile termination) is not connected to the network constantly while the computer is in use, but only during these two transmission events.
The GPRS service is provided to a connection over a GPRS packet data 2o channel (PDCH). Before a C,PRS packet data channel is reserved for a connection requesting such reservation, the GPRS packet data channel must first be allocated to GPRS from a pool of channels also available to other data services and to speech services. A list of the availat>le channels in such pool, known as the GSM
Idle List, is maintained at the base station controller.
z5 Allocation of a packet data channel inv~~lves not only performance of a GPRS channel allocation procedure at the base station controller (BSC), but also performance of a GPRS channel activation procedure (e.g., at the base station).
Whereas the time required at the base station controller to allocate a packet data channel 3o is rather short (on the order of one to two milliseconds), the time required for the GPRS
channel activation procedure is considerably lonjer (e.g.> approximately one hundred milliseconds).
WO 99/5792.1 PCTlSE99/00610 The standards documents concerning the GSM are relatively silent regarding GSM channel allocation. Retarding channel activation, the GSM
standards documents describe that a channel is chosen first by the base station controller and then GS~I channel activation is performed. In this regard, see the GS~I Technical Specification Og.~8 Version x.2.0, July 1996.
GS1~I prescribes a channel release procedure whereby the base station controller releases a radio channel which is no longer needed. In accordance with this GSM channel release procedure, the channel being released is returned to the GSM Idle to List maintained by the base station controller. The base station controller also sends an RF CHANneI RELease message to the relevant transmitter/receiver at the base station, specifying the channel-to-be-released. After having released the addressed sources, the base station sends a RF CH.-A~nel RELease ACKnowledge message to the base station controller.
is In view of the characteristics of GPRS as above described, fast access to GPRS is imperative. The existing circuit switched scheme for accessing and releasing channels is not ideal for GPRS. In the existing circuit switched scheme, a channel is released when it is deallocated. But if a channel has to be allocated main subsequently, zo it must again undergo the time --intensive channel activation procedure.
What is needed therefore, and an obaect of the present invention, is a fast channel allocation procedure for GPRS.
BRIEF SUMMARY OF THE INVENTION
z5 A telecommunications system comprises a control node and a base station node.
The control node maintains a first list of idle radio channels which is consulted in order to obtain channels for a first type of telecommunications service. A second list of idle radio channels is maintained for a specialized telecommunications service, the idle radio channels of the second list being radio channels which are unallocated with respect to 3o the specialized telecommunications service but yet activated (e.g., having an established transmission path and synchronization). The second list of idle radio channels is initially consulted in order to obtain channels for the specialized telecommunications service. If no channels are available for the specialized telecommunications service on WO 99/57924 P~T/SE99/00610 the second list: idle channels from the first list are adapted and utilized for the specialized telecommunications service. The Specialized telecommunications service preferably involves packet data transfer (e.g., GPRS).
In one embodiment, the control node is a base station controller, and the second list is maintained at a packet control node. The packet control node can be co-located with the base station controiller.
BRIEF DESCRIPTION OF THE DRAWINGS
The foregoing and other objects, features, and advantages of the invention will be apparent from the following more particular description of preferred embodiments as to illustrated in the accompanying drawings in which reference characters refer to the same parts throughout the various views. The drawings are not necessarily to scale.
emphasis instead being placed upon illustrating the principles of the invention.
Fig. 1 is a diagrammatic view of a mobile telecommunications network.
Fig. 2 is a schematic view showing a relationship between Fig. 2A and 15 Fig.2B.
Fig. 2A and Fig. 2B are hybrid flowchart/schematic views of basic steps performed in accordance with a channel allocation procedure according to a mode of the invention.
Fig. 3 is a schematic view of an e~cample base station controller (BSC) 2o which operates in accordance with a mode of the present invention.
Fig. 4 is a flovvchart showing basic steps performed in accordance with a procedure of putting channels on a GPRS Idle List according to a mode of the invention.
DETAILED DESCRIPTION OF THE DRAWINGS
25 In the following description, for purposes of explanation and not limitation, WO 99/5792.1 PC'TISE99100610 J
specific details are set forth such as particular architectures, interfaces, techniques, ete.
in order to provide a thorough understanding of the present invention.
However, it will be apparent to those skilled in the art that the present invention may be practiced in other embodiments that dep~rrt from these specific details. In other instances, detailed s descriptions of well known devices, circuits, and methods are omitted so as not to obscure the description of the present invention with unnecessary detail.
Fig. 1 shows a telecommunications network 18 in which a mobile station ?0 communicates with one or more base stations 2'' over air interface (e.g., radio interface) ?3. Base stations 22 are connected by terrestrial lines to base station controller (BSC) Io 24, also known as a radio network controller (RNC). Base station controller'?4 is, in turn, connected through a control node known as the mobile switching center 26 to circuit-switched telephone nf;t.works represented by cloud ~8. In addition, base station controller (BSC) 2=I is connected to Se:vina GPRS Support Node (SGSN) 25 and through backbone network ~7 to a Gateway GRPS support node (GGSN) 30, through is which connection is made with packet-switched telephone networks (e.g., the Internet, X.?5 external networks) represented by cloud 3''.
Gateway GRPS support node (GGSN) 30 provides the interface towards the external IP packet networks and X.2~ networks. Gateway GRPS support node (GGSN) 30 translates data formats, si,;nalling protocols and address information in order to 2o permit communication between the different networks. Backbone network ?7 is an Internet Protocol (IP) networ:k. Serving GPRS Support Node (SGSN) ?5 provides packet routing to an from a SGSN service area, and serves GPRS subscribers which are physically located within the SGSN service area. Serving GPRS Support Node (SGSN) ?5 provides functions such as, authentication, ciphering, mobility management, charging 2s data, and logical link management toward the mobile station. A GPRS
subscriber may be served by any SGSN in the: network depending on location. The GPRS traffic is routed from the Serving GPRS Support Node (SGSN) ?5 to base station controller (BSC) 24 and via base station (BS) 22 to mobile station ?0. The functionality of Serving GPRS Support Node (SGSN) 25 and Gateway GRPS support node (GGSN) 30 3o may be combined in the same node, or may exist in separate nodes as shown in Fig. 1.
WO 99/5792.1 PCT/SE99/00610 As understood by those skilled in the art, when mobile station 20 is participating in a mobile telephonic connection, signaling information and frames of user information from mobile station 20 are transmitted over air interface 23 on designated radio channels to one or more of the base stations 22. The base stations have radio transceivers which transmit: and receive radio signals involved in the connection. For information on the uplink from the mobile station 20 toward the other party involved in the connection, the base stations convert the radio-acquired information to digital signals which are forwarded to base station controller 24. Base station controller 24 orchestrates participation of the plural base stations 22 which may be involved in the to connection, since mobile station 20 may be geographically moving and handover may be occurring relative to the base stations 22. On the upIink, base station controller 24 picks frames of user information from one or more base stations 22 to yield a connection between mobile: station 20 and the other party, whether that party be in PSTN/IDSN 28 or on the Internet 32.
The base station controller (BSC) 2~ of the present invention includes a BSC
central processor (BSC CP) =10. The BSC central processor (BSC CP) 40 includes a GSM Idle List =12, which includes a list of channels which may be allocated for services generally regardless of natiue. Further details of base station controller (BSC) 24 are below described in connection with Fig. 3.
2o The telecommunications network 18 of Fig. 1 also includes a packet control unit node, shown as packet control unit (PCU) 50. The packet control unit (PCLT) ~0 can be separately located relative to other nodes of telecommunications network 18, or can be co-located with another node. In the embodiment herein described in greater detail with respect to Fig. 3, packet control unit (PCU) ~0 is co-located with base station controller (BSC) 24. The packet control unit (PCU) ~0 includes e.g.> a PCU central processor (CP) ~2 and one or more regional processors, of which a PCU regional processor (RP) ~4 is shown in Fig. 1. Of particular importance to the present invention is the fact that PCU regional processor (RP) ~4 includes a GPRS Idle List ~6. As explained in further detail below, GPRS Idle List 56 stores a listing of GPRS channels. While from the 3o circuit switched point of view the channels listed on the GPRS Idle List ~6 are allocated for GPRS, within GPRS such channels have not been reserved, but yet remain activated.
WO 99157924 PC'T/SE99/00610 Further details of packet control unit (PCU) ~0 are below described in connection with Fig. 3.
Fig. 3 shows a particular embodiment of base station controller (BSC) 24 which has co-located thereat the packet control unit (PCU) ~0. As indicated above, packet control unit (PCU) ~0 need not be situated at base station controller (BSC) 24, but can instead be situated at other nodes of telecommunications network I8 or even separately from any other node. Fig. 3 shows base station controller (BSC) 24 interfacing with SGSN 2~, another base station controller (BSC) ?4', and a base station (BS) 2?. It should be understood that base station controller (BSC) 24 can be connected to plural to base station controllers, and likely is connected to plural base stations (BS) ?? (although only singular examples are shown for clarity of illustration).
Generally, base station. controller (BSC) ?=I interfaces to other nodes of telecommunications network 18 in conventional fashion through exchange terminal circuits (ETCs), three such E'CCs 70A - 70C being shown in Fig. 3 for connecting to SGSN 25, base station controller (BSC) y~', and base station (BS) ?'', respectively. In the illustrated embodiment, ETC 70A is connected to SGSN ?~ by a Gb interface (n*64 kbps [n=1,...31 wideband); ETC 70B is connected to base station controller BSCITRC
2=I'; ETC 70C is connected to base station (BS) ~'' by an Abis interface (16 kbps channels having multiplexed ::ircuit switched and packet switched traffic).
The TRC of zo node 24' contains both transcoders and rate adapters. The transcoders are used for speech and the rate adapters for circuit-switched data.
The heart of base station controller (BSC) ''=I is a switch, such as D oup switch (GS) 80 shown in Fig. 3. Group switch (GS) 80 is under control of BSC central processor (BSC CP) 40. Group switch (GS) 80 has ports connected to each of the ETCs 70A - 70C. In addition, group switch (GS) 80 has ports connected to a subrate switch (SRS) 90 and transceiver handler (TRH) 96, as well as to components of packet control unit (PCU) ~0 as shown in Fi g. 3. A TRH has functionality which handles the LAPD
protocol (layer 2) towards Abis, i.e. the TRH handles signaling towards the BS
over Abis.
3o The PCU regional proc; ssor (RP) ~~ of packet control unit (PCU) .50 is shown in Fij. 3 as comprising a power PC 10'_'; one or more digital signal processors 10=I: and plural connection units 106. As mentioned above, PCU regional processor {RP) 54 also includes GPRS Idle List ~6. The PCU regional processor (RP) ~4 is a regional processor with a PCI interface. The PCU regional processor (RP) 54 is configured to handle Gb, Abis, or both.
Each PCU regional processor RP (~4) has sixty four 64-kbitJs device, i.e., multiprocess points toward group switch 80. In particular, each of the DL2s shown in Fig. 3 have 32 such devices. In other than the Gb mode, each device has four subdevices (i.e., 16-kbit/s multiprocessors points connected toward Abis).
It is the allocation of channels, particularly GPRS channels, to which the present io invention primarily relates. As used herein, "channel allocation" refers to a procedure of rendering channels available for use at a base station, whereas ''channel reservation"
refers to the scheduling and multiple;cing of users onto one or more allocated channels.
More particularly, the present invention relates to allocation of GPRS packet data channels (PDCHs). Allocation of a PDCH includes both selection of a suitable channel ~5 from a list of idle channels, as well as channel activation (e.g., preparation of a channel for packet data transfer, including establishment of transmission path and synchronization).
As used herein, ''GPRS" is an example of a specialized telecommunications service for which the GPRS Idle List ~6 is utilized. It should be understood, however, 2o that the invention encompasses uses of plural lists (e.g., first list such as GSM Idle List 42 and second list such as GPRS Idle List ~6) for differing services, and that the characterization of GPRS azid non-GPRS services is provided as an example.
Fig. 2A and Fig. 2B illustrate operation of the present invention and exemplify use of GPRS Idle List ~6. ..As shown by event 2-1 in Fig. 2A, mobile station 2s requests a channel. The channel request is forwarded by base station (BS) 22 to base station controller (BSC) 24. It should be understood, that unless otherwise stated or clear from the context, the events of Fig. 2A and Fig. 2B concerning base station controller (BSC) 24 are peri'ormed by BSC central processor (BSC CP) 40. At event 2-2, base station controller (BSC) 24 determines if the request of event 2-1 is for a GPRS
3o channel.
WO 99/5792-t PCT/SE99/00610 The case of a non-GfRS channel request is first discussed, e.g., that of a request for a circuit switched channel. As indicated by event 2-3, base station controller (BSC) 2~ allocates an idle channel for the request. The idle channel is obtained by consulting GSM Idle List =12 (as indicated by event ?-~. in Fij. ZA). Then, for a non-GPRS channel request (see event ?-~), base station controller (BSC) 24 performs an acceptance check {event ?-6) followed by channel activation i event 2-7). The GSiI~I channel activation (event 2-7) involves various steps. Such steps include base station controller (BSC) 24 sending a channel activation message to the relevant transceiver of the appropriate base station (BS) ??. The channel activation message contains the reason for the activation to (immediate assignment, assignment, handover, additional assignment), the identification of the channel to be used (channel number), and a complete description of the channel (full/half rate, speech/data, coding/rate adaptation, hopping sequence, encryption key, etc., for example). After activating the channel, the transceiver of the base station (BS) 22 responds with a CHANneI ACTIVation ACKnowledge message to base station is controller (BSC) 24.
Next discussed is the case of a GPRS channel request. A PDCH allocation message is sent from BSC cf:ntral processor (BSC CP) 40 through PCU central processor {PC) ~2 and ultimately to PCU regional processor (RP) ~~.. As indicated by event 2-10, a check is made by PCU regional processor (RP) ~4 of packet control unit 20 (PCU) ~0 whether there are already enough available allocated GPRS channels (PDCHs). That is, event ?-10 involves determining whether there is an available allocated, activated GPRS P'.DCH with existing reservations) or "fixed" PDCHs which can be utilized. It should be kept in mind in this regard that several users can share a GPRS PDCH. By "fixed PDCH" is meant a PDCH which can only be deallocated by an 25 operator and which is ordered by an operator. If it is deternuned at event 2-IO that an allocated, activated GPRS P:DCH is available, at event 2-11 such PDCH is reserved.
Then, as indicated by event :?-12, a CHANNEL ASSIGNMENT TO MS message is sent to mobile station (MS) ?0 via base station controller (BSC) ?4 and base station (BS) 22.
If it is determined at event ?-10 that no allocated GPRS PDCH is available (or 3o not enough PDCHs in the case of a mobile station MS requesting several PCDCHs), PCU regional processor (RP) ~4 checks at event ?-13 whether an idle channel can be obtained from GPRS Idle List ~6. The channels listed in GPRS Idle List ~6 are idle in WO 991579Z:i PCT/SE99/00610 the sense that they are not yet allocated to a request for GPRS, although the channels in GPRS Idle List 56 remain activated. As seen hereinafter, by virtue of keeping the channels in GPRS Idle List 5~6 activated, the time-exact procedures of Fig. 2B
need not be performed.
5 Should a channel be available on GPRS Idle List 56, PCU regional processor (RP) 54 reserves such channel (event ?-l l). After the channel reservation of event 2-1 l, a CHANNEL ASSIGNMENT TO MS message is sent to mobile station (MS) 20 via base station controller (BSC) 24 and base station (BS) ?? in the manner illustrated and above described with respect to event 2-1?.
to Should no channel be available on GPRS Idle List 56, PCU regional processor (RP) 54 must request base station controller (BSC) ?4 to determine an appropriate channel responsive to the request, as well as to allocate and activate such appropriate channel. In this regard, at evf:nt ?-3 the base station controller (BSC) 24 references GSM Idle List 42 (see event '-4) to obtain therefrom an idle channel. Since the is obtained idle channel is for GPRS (see event 2-~), the activation procedures of Fij. ?B
are performed.
Fig. 2B shows PCU central processor (CP) ~2, responsive to the determination of event 2-5, preparing (as event '?-?0) an ACTIVATION message to activate the channel allocated at event 2-3. As sh<>wn by event 2-? l, the ACTIVATION message is sent to :?o base station (BS) 22. The base station (BS) 22 determines at event 2-22 whether to accept the ACTIVATION message. If the ACTIVATION message is not accepted, an interrupt is generated (event ?.-23). If the ACTIVATION message is accepted, an ACTIVATION ACKnowledge message is returned to PCU regional processor (RP) 54 (event 2-24) and the air interface initiated (event ?-25). Initiating the air interface as involves starting scheduling of the PDCH multiframe, no power being transmitted.
When PCU regional processor (RP) ~4 determines at event 2-?6 that ACTIVATION ACKnowledge message has been received, an ESTABLISH GSL
procedure is performed to establish a link between the packet control unit (PCU) 50 and base station (BS) ?2. This link is known as GSL or the GPRS signaling link.
The ao ESTABLISH GSL procedure involves setting up transmission paths in the group switch WO 99/51924 PCTlSE99/00610 (GS) 80 of base station controller (BSC) 24 (event 2-?7); synchronization (event 2-28);
and transmission of a PCU frame idle (event ?-29).
Transmission path set. up (event ?-27) is the first action performed by procedure ESTABLISH GSL. The transmission path set up involves choosing a PCU device, belonging to packet control unit (PCU) ~0, from a list, and choosing a PDCH.
Then an order is given to group switch (GS) 80 of base station controller (BSC) 24 to connect the PCU device and the chosen PDCH. Then a connection is established between packet control unit (PCU) ~0 and base station controller (BSC) 24 and synchronization (event 2-28) can be started.
to In connection with synchronization eevent 2-?8), initially only a PCU Frame Sync is sent in both directions. An initial F~i (frame number) synchronization between base station (BS) ?? and packet control unit (PCIJ) ~0 is performed by sending the frame number from base station (BS) ?2 to packet control unit (PCU) ~0. When frame number synchronization is obtained between base station (BS) ?'' and packet control is unit (PCU) ~0, base station (;3S) 22 switches over to sending a PCU Frame Idle event 2-29). Reception by packet control unit (PCLT) 50 of the PCU Frame Idle: is interpreted by PCU regional processor t~E2P) 54 as meaning that the GSL is ready to execute traffic {event ?-30).
After the channel allocated at event ?-3 has been activated in the manner above 2o described with reference to Fig. 2B, PCU regional processor (RP) 54 reserves the channel (event 2-31 ). Then, as event 2-32, a CHANNEL ASSIGNMENT TO i~IS
message is sent to mobile station (MS) ?0 via base station controller (BSC) ?4 and base station (BS) ??.
As long as the PDCH exists, an adaptive PCLT frame alignment procedure runs 2s autonomously. The adaptive PCU frame alignment procedure is used to minimize delay through base station (BS) ~'~'. To achieve this, the alignment between radio blocks sent on the air interface and the PCU frames sent on GSL is continuously monitored and, if necessary, adjusted. The adaptive PCU frame alignment procedure has to be restarted if the PDCH is released.
WO 99157924 PC'T/SE99/00610 1?
Thus, as described above, when a request is issued for a GPRS channel, the GPRS Idle List ~6 a consultf:d to determine if any available. unallocated GPRS
PDCHs exist (event 2-13). If a channel is available as ascertained from GPRS Idle List ~6, a reservation can be made essentially immediately (event 2-I I). If a GPRS PDCH
is not s available from GPRS Idle List ~6, a channel is fetched from GSM Idle List 42.
However, if a channel is fetched from GSM Idle List 42, such channel has to be PDCH
allocated, activated, and reserved (as described with reference to the events shown in Fig. 2B).
The GPRS Idle List 5~6 thus contains channels that, while allocated from the to circuit switched perspective ~,e.g., no longer on GSM Idle List -1?), are unallocated from the GPRS perspective. That is, while the channels on GPRS Idle List ~6 are already activated, such channels have no reservations, i.e., no on-going traffic. In addition, it is possible that a fixed channel may not be put into GPRS Idle List 56 even. if it has no traffic. Such a fixed channel can only be taken down by the operator, but once taken is down such fixed channel is eligible for posting on GPRS Idle List ~6.
With reference to the events shown in Fig. 2A, it may occur that no channels are available from GS1~I Idle List :I? when a request is made for a non-GPRS
channel (e.g., for a circuit switched channel). In such case, in one embodiment of the invention base station controller (BSC) 2=~ is permitted to takes a PDCH from the GPRS Idle List ~6, 20 or preempt a busy PDCH. To do so, the GPRS links (connections) must be taken down, and the channel activated as a circuit switched channel in accordance with conventional practice (e.g., as if it had come from GSM Idle List 42 rather than from GPRS
Idle List 56).
Fig. 4 basically shows putting on a GPRS Idle list a GPRS PDCH when the 2s mobile station MS previously using such PDCH has no more data presently to send.
Event 4-1 shows mobile station informing PCU 50 that the mobile station >VIS
has no more data to send. The message of event 4-l, received by base station controller (BSC) 24, is forwarded to PCU regional processor (RP) ~4 of packet control unit (PCU) 50.
As event 4-2, PCU regional processor (RP) ~~ de-reserves (e.g., removes the reservation) for the GPRS PDCH by mobile station ?0. Then, as event ~-3, the PCU
regional processor (RP) ~~ determines whether the mobile station which requested the release of the GPRS PDCH at event -~-1 was the last mobile station using that GPRS
WO 99/5792. PCT/SE99/00610 PDCH. If the determination at event ~-3 is affirmative, as event 4-4 the PCU
regional processor (RP) ~4 puts that p~uticular GPRS PDCH on GPRS Idle List ~6 before exiting the procedure (indicated by event 4-~).
Fixed channels allocated by the operator cannot be deallocated by means other than by the operator. Therefore, fixed channels are not added to GPRS Idle List ~6 even if thev have no traffic.
By putting GPRS PDCHs on GPRS Idle List 56 rather than deactivating them, packet control unit (PCU) 50 maintains a pool of ready-to-reserve PDCHs that would not have to be re-activated should they be needed again. Such is particularly to advantageous and saves the activation procedures shown in Fig. '?B, including transmission path set up and synchronization, in a case in which a PDCH can be obtained from GPRS Idle List: :~6. This enables GPRS to efficiently allocate channels despite their bursty employment, thereby rendering GPRS competitive with circuit switched data services.
is The present invention provides a fast GPRS access by, upon deservation of a last mobile station using the GPRS PDCH, keeping the GPRS PDCH activated at base station (BS) 22 and keeping the GPRS signaling link (GSLj to packet control unit (PCU) 50 established. The non-reserved but still-activated GPRS channels which are no longer utilized for GPRS ts~affic are put in GPRS Idle List ~6. Thereby, when GPRS
:?o needs another channel, a channel from GPRS Idle List ~6 is chosen first, in which case the channel activation procedure (illustrated, e.g., in Fig. 2B) had already been performed. This saves time, e~.~., about 100 milliseconds, and provides GPRS
users with fast access.
While base station conetroller (BSC) 24 has been illustrated as including group :'S switch (GS) 80, it should also be understood that the present invention can be implemented with other types of switches and thus other types of data transmission, e.g., for example ATNI switches.
While the invention has been described in connection with what is presently considered to be the most practical and preferred e.mbudiment, it is to be understood 3o that the invention is not to be limited to the disclosed ;:mbudiment, but on the contrary, WO 99/57924 PCTlSE99/00610 i4 is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims. For example, the principles of the invention are not confined to a GSM system, but instead are applicable to any telecommunications system wherein it is advantageous to maintain channels activated but not reserved for a particular service.
Furthermore, the second list, of which GPRS Idle List 56 is an example, need not necessarily be maintained at any particular node. While in the foregoing description GPRS Idle List ~6 has been illustrated as included in packet control unit (PCLT) S0, the person skilled in the art will rf:alize that GPRS Idle List ~6 could alternatively be o provided at another node, such as base station controller (BSC) 24, for example.
In the embodiments described above, GPRS Idle List ~6 has been particularly shown as maintained by PCU regional processor (RP) 5~. of packet control unit (PCU) 50. Such location of GPRS Idle List ~6 is just one implementation choice.
Indeed, GPRS Idle List ~o could be provided in a processor other than a regional processor, is such as PCU central processor (CP) ~?, for example.
Placement of packet control unit (PCL') ~0 may influence the amount of time saved in GPRS access. For e:rample, if packet control unit (PCU) ~0 is co-located with base station (BS) 22 rather than base station controller (BSC) 24, a smaller time saving may be realized. On the other hand, if packet control unit (PCU) ~0 coexists with an SGSN, there may be a largertime saving even then when packet control unit (PCU) 50 coexists with base station controller (BSC) ?4.
It will also be appreciated that a mobile station can request several PDCHs.
For example, one mobile station rnay obtain several time slots (PDCHs), thereby obtaining a higher bandwidth.
In recent years cellular telephones have become increasingly popular. A
cellular to telephone is just one example of what is referred to in telephone parlance as a "mobile station" or "mobile terminal". Telecommunications services are provided between a cellular telecommunications network and a mobile station (e.g., cellular telephone) over an air interface, e.g., over radio frequencies. At any moment an active mobile station is communicating over the air interface with one or more base stations. The base stations :a are, in turn, managed by base station controllers {BSCs). The base station controllers are connected via control nodEa to a core teleconunun~~ations network.
Examples of control nodes include a mobile switching center (I~iSC) node for connecting to connection-oriented, circuit switched networks such as PSTN and/or ISDN, and a general packet radio service (CiPRS) node for connecting to packet-switched networks such as Internet. for example.
A mobile station can take on various forms other than a cellular telephone, including a comput~°r (e.g., a laptop computer) with mobile termination capabilities. In .some forms, n-labile stations are capable of engaging in differing types WO 9915792.1 PCT/SE99/00610 of services, or multimedia services. In other words, the mobile station can execute several differing types of pro;~rams (i.e., ''applications") which interact with the user.
Examples of these applications include Internet browsers and electronic mail programs.
Several multimedia applications may reside in the same mobile station.
One type of standardized mobile telecommunications scheme, utilized, e.g., in Europe, is the Global System for Mobile communications (GSM). GSM
includes standards which specify functions and interfaces for various types of services.
A relatively recent rata service available within the GSM system is General Packet io Radio Service (GPRS). GPRS differs from existinD data services in that GPRS
is a packet switched service instead of a circuit switched data service. Whereas (in GSM) a circuit switched data user is connected continuously to the radio network during a data call (e.g., even when not transferring data), a GPRS user is connected to the radio network only when either (:l) the mobile station desires to transmit or (?) the network has something to transmit to t:he mobile station. In other words, in GPRS the mobile station (e.g., a computer with mobile termination) is not connected to the network constantly while the computer is in use, but only during these two transmission events.
The GPRS service is provided to a connection over a GPRS packet data 2o channel (PDCH). Before a C,PRS packet data channel is reserved for a connection requesting such reservation, the GPRS packet data channel must first be allocated to GPRS from a pool of channels also available to other data services and to speech services. A list of the availat>le channels in such pool, known as the GSM
Idle List, is maintained at the base station controller.
z5 Allocation of a packet data channel inv~~lves not only performance of a GPRS channel allocation procedure at the base station controller (BSC), but also performance of a GPRS channel activation procedure (e.g., at the base station).
Whereas the time required at the base station controller to allocate a packet data channel 3o is rather short (on the order of one to two milliseconds), the time required for the GPRS
channel activation procedure is considerably lonjer (e.g.> approximately one hundred milliseconds).
WO 99/5792.1 PCTlSE99/00610 The standards documents concerning the GSM are relatively silent regarding GSM channel allocation. Retarding channel activation, the GSM
standards documents describe that a channel is chosen first by the base station controller and then GS~I channel activation is performed. In this regard, see the GS~I Technical Specification Og.~8 Version x.2.0, July 1996.
GS1~I prescribes a channel release procedure whereby the base station controller releases a radio channel which is no longer needed. In accordance with this GSM channel release procedure, the channel being released is returned to the GSM Idle to List maintained by the base station controller. The base station controller also sends an RF CHANneI RELease message to the relevant transmitter/receiver at the base station, specifying the channel-to-be-released. After having released the addressed sources, the base station sends a RF CH.-A~nel RELease ACKnowledge message to the base station controller.
is In view of the characteristics of GPRS as above described, fast access to GPRS is imperative. The existing circuit switched scheme for accessing and releasing channels is not ideal for GPRS. In the existing circuit switched scheme, a channel is released when it is deallocated. But if a channel has to be allocated main subsequently, zo it must again undergo the time --intensive channel activation procedure.
What is needed therefore, and an obaect of the present invention, is a fast channel allocation procedure for GPRS.
BRIEF SUMMARY OF THE INVENTION
z5 A telecommunications system comprises a control node and a base station node.
The control node maintains a first list of idle radio channels which is consulted in order to obtain channels for a first type of telecommunications service. A second list of idle radio channels is maintained for a specialized telecommunications service, the idle radio channels of the second list being radio channels which are unallocated with respect to 3o the specialized telecommunications service but yet activated (e.g., having an established transmission path and synchronization). The second list of idle radio channels is initially consulted in order to obtain channels for the specialized telecommunications service. If no channels are available for the specialized telecommunications service on WO 99/57924 P~T/SE99/00610 the second list: idle channels from the first list are adapted and utilized for the specialized telecommunications service. The Specialized telecommunications service preferably involves packet data transfer (e.g., GPRS).
In one embodiment, the control node is a base station controller, and the second list is maintained at a packet control node. The packet control node can be co-located with the base station controiller.
BRIEF DESCRIPTION OF THE DRAWINGS
The foregoing and other objects, features, and advantages of the invention will be apparent from the following more particular description of preferred embodiments as to illustrated in the accompanying drawings in which reference characters refer to the same parts throughout the various views. The drawings are not necessarily to scale.
emphasis instead being placed upon illustrating the principles of the invention.
Fig. 1 is a diagrammatic view of a mobile telecommunications network.
Fig. 2 is a schematic view showing a relationship between Fig. 2A and 15 Fig.2B.
Fig. 2A and Fig. 2B are hybrid flowchart/schematic views of basic steps performed in accordance with a channel allocation procedure according to a mode of the invention.
Fig. 3 is a schematic view of an e~cample base station controller (BSC) 2o which operates in accordance with a mode of the present invention.
Fig. 4 is a flovvchart showing basic steps performed in accordance with a procedure of putting channels on a GPRS Idle List according to a mode of the invention.
DETAILED DESCRIPTION OF THE DRAWINGS
25 In the following description, for purposes of explanation and not limitation, WO 99/5792.1 PC'TISE99100610 J
specific details are set forth such as particular architectures, interfaces, techniques, ete.
in order to provide a thorough understanding of the present invention.
However, it will be apparent to those skilled in the art that the present invention may be practiced in other embodiments that dep~rrt from these specific details. In other instances, detailed s descriptions of well known devices, circuits, and methods are omitted so as not to obscure the description of the present invention with unnecessary detail.
Fig. 1 shows a telecommunications network 18 in which a mobile station ?0 communicates with one or more base stations 2'' over air interface (e.g., radio interface) ?3. Base stations 22 are connected by terrestrial lines to base station controller (BSC) Io 24, also known as a radio network controller (RNC). Base station controller'?4 is, in turn, connected through a control node known as the mobile switching center 26 to circuit-switched telephone nf;t.works represented by cloud ~8. In addition, base station controller (BSC) 2=I is connected to Se:vina GPRS Support Node (SGSN) 25 and through backbone network ~7 to a Gateway GRPS support node (GGSN) 30, through is which connection is made with packet-switched telephone networks (e.g., the Internet, X.?5 external networks) represented by cloud 3''.
Gateway GRPS support node (GGSN) 30 provides the interface towards the external IP packet networks and X.2~ networks. Gateway GRPS support node (GGSN) 30 translates data formats, si,;nalling protocols and address information in order to 2o permit communication between the different networks. Backbone network ?7 is an Internet Protocol (IP) networ:k. Serving GPRS Support Node (SGSN) ?5 provides packet routing to an from a SGSN service area, and serves GPRS subscribers which are physically located within the SGSN service area. Serving GPRS Support Node (SGSN) ?5 provides functions such as, authentication, ciphering, mobility management, charging 2s data, and logical link management toward the mobile station. A GPRS
subscriber may be served by any SGSN in the: network depending on location. The GPRS traffic is routed from the Serving GPRS Support Node (SGSN) ?5 to base station controller (BSC) 24 and via base station (BS) 22 to mobile station ?0. The functionality of Serving GPRS Support Node (SGSN) 25 and Gateway GRPS support node (GGSN) 30 3o may be combined in the same node, or may exist in separate nodes as shown in Fig. 1.
WO 99/5792.1 PCT/SE99/00610 As understood by those skilled in the art, when mobile station 20 is participating in a mobile telephonic connection, signaling information and frames of user information from mobile station 20 are transmitted over air interface 23 on designated radio channels to one or more of the base stations 22. The base stations have radio transceivers which transmit: and receive radio signals involved in the connection. For information on the uplink from the mobile station 20 toward the other party involved in the connection, the base stations convert the radio-acquired information to digital signals which are forwarded to base station controller 24. Base station controller 24 orchestrates participation of the plural base stations 22 which may be involved in the to connection, since mobile station 20 may be geographically moving and handover may be occurring relative to the base stations 22. On the upIink, base station controller 24 picks frames of user information from one or more base stations 22 to yield a connection between mobile: station 20 and the other party, whether that party be in PSTN/IDSN 28 or on the Internet 32.
The base station controller (BSC) 2~ of the present invention includes a BSC
central processor (BSC CP) =10. The BSC central processor (BSC CP) 40 includes a GSM Idle List =12, which includes a list of channels which may be allocated for services generally regardless of natiue. Further details of base station controller (BSC) 24 are below described in connection with Fig. 3.
2o The telecommunications network 18 of Fig. 1 also includes a packet control unit node, shown as packet control unit (PCU) 50. The packet control unit (PCLT) ~0 can be separately located relative to other nodes of telecommunications network 18, or can be co-located with another node. In the embodiment herein described in greater detail with respect to Fig. 3, packet control unit (PCU) ~0 is co-located with base station controller (BSC) 24. The packet control unit (PCU) ~0 includes e.g.> a PCU central processor (CP) ~2 and one or more regional processors, of which a PCU regional processor (RP) ~4 is shown in Fig. 1. Of particular importance to the present invention is the fact that PCU regional processor (RP) ~4 includes a GPRS Idle List ~6. As explained in further detail below, GPRS Idle List 56 stores a listing of GPRS channels. While from the 3o circuit switched point of view the channels listed on the GPRS Idle List ~6 are allocated for GPRS, within GPRS such channels have not been reserved, but yet remain activated.
WO 99157924 PC'T/SE99/00610 Further details of packet control unit (PCU) ~0 are below described in connection with Fig. 3.
Fig. 3 shows a particular embodiment of base station controller (BSC) 24 which has co-located thereat the packet control unit (PCU) ~0. As indicated above, packet control unit (PCU) ~0 need not be situated at base station controller (BSC) 24, but can instead be situated at other nodes of telecommunications network I8 or even separately from any other node. Fig. 3 shows base station controller (BSC) 24 interfacing with SGSN 2~, another base station controller (BSC) ?4', and a base station (BS) 2?. It should be understood that base station controller (BSC) 24 can be connected to plural to base station controllers, and likely is connected to plural base stations (BS) ?? (although only singular examples are shown for clarity of illustration).
Generally, base station. controller (BSC) ?=I interfaces to other nodes of telecommunications network 18 in conventional fashion through exchange terminal circuits (ETCs), three such E'CCs 70A - 70C being shown in Fig. 3 for connecting to SGSN 25, base station controller (BSC) y~', and base station (BS) ?'', respectively. In the illustrated embodiment, ETC 70A is connected to SGSN ?~ by a Gb interface (n*64 kbps [n=1,...31 wideband); ETC 70B is connected to base station controller BSCITRC
2=I'; ETC 70C is connected to base station (BS) ~'' by an Abis interface (16 kbps channels having multiplexed ::ircuit switched and packet switched traffic).
The TRC of zo node 24' contains both transcoders and rate adapters. The transcoders are used for speech and the rate adapters for circuit-switched data.
The heart of base station controller (BSC) ''=I is a switch, such as D oup switch (GS) 80 shown in Fig. 3. Group switch (GS) 80 is under control of BSC central processor (BSC CP) 40. Group switch (GS) 80 has ports connected to each of the ETCs 70A - 70C. In addition, group switch (GS) 80 has ports connected to a subrate switch (SRS) 90 and transceiver handler (TRH) 96, as well as to components of packet control unit (PCU) ~0 as shown in Fi g. 3. A TRH has functionality which handles the LAPD
protocol (layer 2) towards Abis, i.e. the TRH handles signaling towards the BS
over Abis.
3o The PCU regional proc; ssor (RP) ~~ of packet control unit (PCU) .50 is shown in Fij. 3 as comprising a power PC 10'_'; one or more digital signal processors 10=I: and plural connection units 106. As mentioned above, PCU regional processor {RP) 54 also includes GPRS Idle List ~6. The PCU regional processor (RP) ~4 is a regional processor with a PCI interface. The PCU regional processor (RP) 54 is configured to handle Gb, Abis, or both.
Each PCU regional processor RP (~4) has sixty four 64-kbitJs device, i.e., multiprocess points toward group switch 80. In particular, each of the DL2s shown in Fig. 3 have 32 such devices. In other than the Gb mode, each device has four subdevices (i.e., 16-kbit/s multiprocessors points connected toward Abis).
It is the allocation of channels, particularly GPRS channels, to which the present io invention primarily relates. As used herein, "channel allocation" refers to a procedure of rendering channels available for use at a base station, whereas ''channel reservation"
refers to the scheduling and multiple;cing of users onto one or more allocated channels.
More particularly, the present invention relates to allocation of GPRS packet data channels (PDCHs). Allocation of a PDCH includes both selection of a suitable channel ~5 from a list of idle channels, as well as channel activation (e.g., preparation of a channel for packet data transfer, including establishment of transmission path and synchronization).
As used herein, ''GPRS" is an example of a specialized telecommunications service for which the GPRS Idle List ~6 is utilized. It should be understood, however, 2o that the invention encompasses uses of plural lists (e.g., first list such as GSM Idle List 42 and second list such as GPRS Idle List ~6) for differing services, and that the characterization of GPRS azid non-GPRS services is provided as an example.
Fig. 2A and Fig. 2B illustrate operation of the present invention and exemplify use of GPRS Idle List ~6. ..As shown by event 2-1 in Fig. 2A, mobile station 2s requests a channel. The channel request is forwarded by base station (BS) 22 to base station controller (BSC) 24. It should be understood, that unless otherwise stated or clear from the context, the events of Fig. 2A and Fig. 2B concerning base station controller (BSC) 24 are peri'ormed by BSC central processor (BSC CP) 40. At event 2-2, base station controller (BSC) 24 determines if the request of event 2-1 is for a GPRS
3o channel.
WO 99/5792-t PCT/SE99/00610 The case of a non-GfRS channel request is first discussed, e.g., that of a request for a circuit switched channel. As indicated by event 2-3, base station controller (BSC) 2~ allocates an idle channel for the request. The idle channel is obtained by consulting GSM Idle List =12 (as indicated by event ?-~. in Fij. ZA). Then, for a non-GPRS channel request (see event ?-~), base station controller (BSC) 24 performs an acceptance check {event ?-6) followed by channel activation i event 2-7). The GSiI~I channel activation (event 2-7) involves various steps. Such steps include base station controller (BSC) 24 sending a channel activation message to the relevant transceiver of the appropriate base station (BS) ??. The channel activation message contains the reason for the activation to (immediate assignment, assignment, handover, additional assignment), the identification of the channel to be used (channel number), and a complete description of the channel (full/half rate, speech/data, coding/rate adaptation, hopping sequence, encryption key, etc., for example). After activating the channel, the transceiver of the base station (BS) 22 responds with a CHANneI ACTIVation ACKnowledge message to base station is controller (BSC) 24.
Next discussed is the case of a GPRS channel request. A PDCH allocation message is sent from BSC cf:ntral processor (BSC CP) 40 through PCU central processor {PC) ~2 and ultimately to PCU regional processor (RP) ~~.. As indicated by event 2-10, a check is made by PCU regional processor (RP) ~4 of packet control unit 20 (PCU) ~0 whether there are already enough available allocated GPRS channels (PDCHs). That is, event ?-10 involves determining whether there is an available allocated, activated GPRS P'.DCH with existing reservations) or "fixed" PDCHs which can be utilized. It should be kept in mind in this regard that several users can share a GPRS PDCH. By "fixed PDCH" is meant a PDCH which can only be deallocated by an 25 operator and which is ordered by an operator. If it is deternuned at event 2-IO that an allocated, activated GPRS P:DCH is available, at event 2-11 such PDCH is reserved.
Then, as indicated by event :?-12, a CHANNEL ASSIGNMENT TO MS message is sent to mobile station (MS) ?0 via base station controller (BSC) ?4 and base station (BS) 22.
If it is determined at event ?-10 that no allocated GPRS PDCH is available (or 3o not enough PDCHs in the case of a mobile station MS requesting several PCDCHs), PCU regional processor (RP) ~4 checks at event ?-13 whether an idle channel can be obtained from GPRS Idle List ~6. The channels listed in GPRS Idle List ~6 are idle in WO 991579Z:i PCT/SE99/00610 the sense that they are not yet allocated to a request for GPRS, although the channels in GPRS Idle List 56 remain activated. As seen hereinafter, by virtue of keeping the channels in GPRS Idle List 5~6 activated, the time-exact procedures of Fig. 2B
need not be performed.
5 Should a channel be available on GPRS Idle List 56, PCU regional processor (RP) 54 reserves such channel (event ?-l l). After the channel reservation of event 2-1 l, a CHANNEL ASSIGNMENT TO MS message is sent to mobile station (MS) 20 via base station controller (BSC) 24 and base station (BS) ?? in the manner illustrated and above described with respect to event 2-1?.
to Should no channel be available on GPRS Idle List 56, PCU regional processor (RP) 54 must request base station controller (BSC) ?4 to determine an appropriate channel responsive to the request, as well as to allocate and activate such appropriate channel. In this regard, at evf:nt ?-3 the base station controller (BSC) 24 references GSM Idle List 42 (see event '-4) to obtain therefrom an idle channel. Since the is obtained idle channel is for GPRS (see event 2-~), the activation procedures of Fij. ?B
are performed.
Fig. 2B shows PCU central processor (CP) ~2, responsive to the determination of event 2-5, preparing (as event '?-?0) an ACTIVATION message to activate the channel allocated at event 2-3. As sh<>wn by event 2-? l, the ACTIVATION message is sent to :?o base station (BS) 22. The base station (BS) 22 determines at event 2-22 whether to accept the ACTIVATION message. If the ACTIVATION message is not accepted, an interrupt is generated (event ?.-23). If the ACTIVATION message is accepted, an ACTIVATION ACKnowledge message is returned to PCU regional processor (RP) 54 (event 2-24) and the air interface initiated (event ?-25). Initiating the air interface as involves starting scheduling of the PDCH multiframe, no power being transmitted.
When PCU regional processor (RP) ~4 determines at event 2-?6 that ACTIVATION ACKnowledge message has been received, an ESTABLISH GSL
procedure is performed to establish a link between the packet control unit (PCU) 50 and base station (BS) ?2. This link is known as GSL or the GPRS signaling link.
The ao ESTABLISH GSL procedure involves setting up transmission paths in the group switch WO 99/51924 PCTlSE99/00610 (GS) 80 of base station controller (BSC) 24 (event 2-?7); synchronization (event 2-28);
and transmission of a PCU frame idle (event ?-29).
Transmission path set. up (event ?-27) is the first action performed by procedure ESTABLISH GSL. The transmission path set up involves choosing a PCU device, belonging to packet control unit (PCU) ~0, from a list, and choosing a PDCH.
Then an order is given to group switch (GS) 80 of base station controller (BSC) 24 to connect the PCU device and the chosen PDCH. Then a connection is established between packet control unit (PCU) ~0 and base station controller (BSC) 24 and synchronization (event 2-28) can be started.
to In connection with synchronization eevent 2-?8), initially only a PCU Frame Sync is sent in both directions. An initial F~i (frame number) synchronization between base station (BS) ?? and packet control unit (PCIJ) ~0 is performed by sending the frame number from base station (BS) ?2 to packet control unit (PCU) ~0. When frame number synchronization is obtained between base station (BS) ?'' and packet control is unit (PCU) ~0, base station (;3S) 22 switches over to sending a PCU Frame Idle event 2-29). Reception by packet control unit (PCLT) 50 of the PCU Frame Idle: is interpreted by PCU regional processor t~E2P) 54 as meaning that the GSL is ready to execute traffic {event ?-30).
After the channel allocated at event ?-3 has been activated in the manner above 2o described with reference to Fig. 2B, PCU regional processor (RP) 54 reserves the channel (event 2-31 ). Then, as event 2-32, a CHANNEL ASSIGNMENT TO i~IS
message is sent to mobile station (MS) ?0 via base station controller (BSC) ?4 and base station (BS) ??.
As long as the PDCH exists, an adaptive PCLT frame alignment procedure runs 2s autonomously. The adaptive PCU frame alignment procedure is used to minimize delay through base station (BS) ~'~'. To achieve this, the alignment between radio blocks sent on the air interface and the PCU frames sent on GSL is continuously monitored and, if necessary, adjusted. The adaptive PCU frame alignment procedure has to be restarted if the PDCH is released.
WO 99157924 PC'T/SE99/00610 1?
Thus, as described above, when a request is issued for a GPRS channel, the GPRS Idle List ~6 a consultf:d to determine if any available. unallocated GPRS
PDCHs exist (event 2-13). If a channel is available as ascertained from GPRS Idle List ~6, a reservation can be made essentially immediately (event 2-I I). If a GPRS PDCH
is not s available from GPRS Idle List ~6, a channel is fetched from GSM Idle List 42.
However, if a channel is fetched from GSM Idle List 42, such channel has to be PDCH
allocated, activated, and reserved (as described with reference to the events shown in Fig. 2B).
The GPRS Idle List 5~6 thus contains channels that, while allocated from the to circuit switched perspective ~,e.g., no longer on GSM Idle List -1?), are unallocated from the GPRS perspective. That is, while the channels on GPRS Idle List ~6 are already activated, such channels have no reservations, i.e., no on-going traffic. In addition, it is possible that a fixed channel may not be put into GPRS Idle List 56 even. if it has no traffic. Such a fixed channel can only be taken down by the operator, but once taken is down such fixed channel is eligible for posting on GPRS Idle List ~6.
With reference to the events shown in Fig. 2A, it may occur that no channels are available from GS1~I Idle List :I? when a request is made for a non-GPRS
channel (e.g., for a circuit switched channel). In such case, in one embodiment of the invention base station controller (BSC) 2=~ is permitted to takes a PDCH from the GPRS Idle List ~6, 20 or preempt a busy PDCH. To do so, the GPRS links (connections) must be taken down, and the channel activated as a circuit switched channel in accordance with conventional practice (e.g., as if it had come from GSM Idle List 42 rather than from GPRS
Idle List 56).
Fig. 4 basically shows putting on a GPRS Idle list a GPRS PDCH when the 2s mobile station MS previously using such PDCH has no more data presently to send.
Event 4-1 shows mobile station informing PCU 50 that the mobile station >VIS
has no more data to send. The message of event 4-l, received by base station controller (BSC) 24, is forwarded to PCU regional processor (RP) ~4 of packet control unit (PCU) 50.
As event 4-2, PCU regional processor (RP) ~~ de-reserves (e.g., removes the reservation) for the GPRS PDCH by mobile station ?0. Then, as event ~-3, the PCU
regional processor (RP) ~~ determines whether the mobile station which requested the release of the GPRS PDCH at event -~-1 was the last mobile station using that GPRS
WO 99/5792. PCT/SE99/00610 PDCH. If the determination at event ~-3 is affirmative, as event 4-4 the PCU
regional processor (RP) ~4 puts that p~uticular GPRS PDCH on GPRS Idle List ~6 before exiting the procedure (indicated by event 4-~).
Fixed channels allocated by the operator cannot be deallocated by means other than by the operator. Therefore, fixed channels are not added to GPRS Idle List ~6 even if thev have no traffic.
By putting GPRS PDCHs on GPRS Idle List 56 rather than deactivating them, packet control unit (PCU) 50 maintains a pool of ready-to-reserve PDCHs that would not have to be re-activated should they be needed again. Such is particularly to advantageous and saves the activation procedures shown in Fig. '?B, including transmission path set up and synchronization, in a case in which a PDCH can be obtained from GPRS Idle List: :~6. This enables GPRS to efficiently allocate channels despite their bursty employment, thereby rendering GPRS competitive with circuit switched data services.
is The present invention provides a fast GPRS access by, upon deservation of a last mobile station using the GPRS PDCH, keeping the GPRS PDCH activated at base station (BS) 22 and keeping the GPRS signaling link (GSLj to packet control unit (PCU) 50 established. The non-reserved but still-activated GPRS channels which are no longer utilized for GPRS ts~affic are put in GPRS Idle List ~6. Thereby, when GPRS
:?o needs another channel, a channel from GPRS Idle List ~6 is chosen first, in which case the channel activation procedure (illustrated, e.g., in Fig. 2B) had already been performed. This saves time, e~.~., about 100 milliseconds, and provides GPRS
users with fast access.
While base station conetroller (BSC) 24 has been illustrated as including group :'S switch (GS) 80, it should also be understood that the present invention can be implemented with other types of switches and thus other types of data transmission, e.g., for example ATNI switches.
While the invention has been described in connection with what is presently considered to be the most practical and preferred e.mbudiment, it is to be understood 3o that the invention is not to be limited to the disclosed ;:mbudiment, but on the contrary, WO 99/57924 PCTlSE99/00610 i4 is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims. For example, the principles of the invention are not confined to a GSM system, but instead are applicable to any telecommunications system wherein it is advantageous to maintain channels activated but not reserved for a particular service.
Furthermore, the second list, of which GPRS Idle List 56 is an example, need not necessarily be maintained at any particular node. While in the foregoing description GPRS Idle List ~6 has been illustrated as included in packet control unit (PCLT) S0, the person skilled in the art will rf:alize that GPRS Idle List ~6 could alternatively be o provided at another node, such as base station controller (BSC) 24, for example.
In the embodiments described above, GPRS Idle List ~6 has been particularly shown as maintained by PCU regional processor (RP) 5~. of packet control unit (PCU) 50. Such location of GPRS Idle List ~6 is just one implementation choice.
Indeed, GPRS Idle List ~o could be provided in a processor other than a regional processor, is such as PCU central processor (CP) ~?, for example.
Placement of packet control unit (PCL') ~0 may influence the amount of time saved in GPRS access. For e:rample, if packet control unit (PCU) ~0 is co-located with base station (BS) 22 rather than base station controller (BSC) 24, a smaller time saving may be realized. On the other hand, if packet control unit (PCU) ~0 coexists with an SGSN, there may be a largertime saving even then when packet control unit (PCU) 50 coexists with base station controller (BSC) ?4.
It will also be appreciated that a mobile station can request several PDCHs.
For example, one mobile station rnay obtain several time slots (PDCHs), thereby obtaining a higher bandwidth.
Claims (14)
1. A telecommunications system comprising a control node and a base station node, wherein the control node maintains a first list of idle radio channels which are available for a first type of telecommunications service, wherein the improvement comprises a second list of idle radio channels which are available for a specialized telecommunications service, the idle radio channels of the second list being radio channels which are unreserved with respect to the specialized telecommunications service but yet activated.
2. The apparatus of claim 1, wherein the specialized telecommunications service involves packet data transfer.
3. The apparatus of claim 1, wherein the first type of telecommunications service is a circuit switched service.
4. The apparatus of claim 1, wherein control node is a base station controller, and wherein the second list is maintained at a packet control node which is co-located with the base station controller.
5. The apparatus of claim 1, wherein the second list is maintained by a processor of the packet control node.
6. The apparatus of claim 5, wherein the second list is maintained by a regional processor of the packet control node.
7. The apparatus of claim 1, wherein the telecommunications system further comprises a base station control node, and wherein a signaling link and transmission path through the base station control node exists for the idle radio channels of the second list.
8. The apparatus of claim 1, wherein the second list is devoid of any idle radio channels, the specialized telecommunications service obtains an allocated channel from the first list, whereupon the control node activates the allocated channel obtained from the first list.
9. A method of operating a telecommunications system comprising a control node and a base station node, the method comprising:
maintaining a first list of idle radio channels which are available for a first type of telecommunications service;
maintaining a second list of idle radio channels which are available for a specialized telecommunications service, the idle radio channels of the second list being radio channels which are unreserved with respect to the specialized telecommunications service but yet activated at the base station node;
responding to a request for a radio channel for use by the specialized service by choosing a radio channel from the second list.
maintaining a first list of idle radio channels which are available for a first type of telecommunications service;
maintaining a second list of idle radio channels which are available for a specialized telecommunications service, the idle radio channels of the second list being radio channels which are unreserved with respect to the specialized telecommunications service but yet activated at the base station node;
responding to a request for a radio channel for use by the specialized service by choosing a radio channel from the second list.
10. The method of claim 9, wherein the specialized telecommunications service involves packet data transfer.
11. The method of claim 9, wherein the first telecommunications service is a circuit switched service.
12. The method of claim 9, further comprising responding to a request for a radio channel for use by the first type of telecommunications service by choosing a radio channel from the first list, and if the first list is empty releasing a radio channel from the second list and choosing the released radio channel.
13. The method of claim 9, further comprising maintaining a signaling link and transmission path through a base station control node for an idle radio channels of the second list after the idle radio channels of the second list is unreserved.
14. The method of claim 9, wherein when the second list is devoid of any idle radio channels, the method further comprises the specialized telecommunications service obtaining an allocated channel from the first list, whereupon the control node activates the allocated channel obtained from the first list.
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US09/069,939 US5978368A (en) | 1998-04-30 | 1998-04-30 | Allocation of channels for packet data services |
| US09/069,939 | 1998-04-30 | ||
| PCT/SE1999/000610 WO1999057924A1 (en) | 1998-04-30 | 1999-04-16 | Allocation of channels for packet data services |
Publications (1)
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|---|---|
| CA2330845A1 true CA2330845A1 (en) | 1999-11-11 |
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| CA002330845A Abandoned CA2330845A1 (en) | 1998-04-30 | 1999-04-16 | Allocation of channels for packet data services |
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| US (1) | US5978368A (en) |
| CN (1) | CN1270554C (en) |
| AU (1) | AU4298399A (en) |
| BR (1) | BR9910067A (en) |
| CA (1) | CA2330845A1 (en) |
| DE (1) | DE19983154B4 (en) |
| GB (1) | GB2354136B (en) |
| WO (1) | WO1999057924A1 (en) |
Families Citing this family (55)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP3324521B2 (en) * | 1997-10-03 | 2002-09-17 | 三菱マテリアル株式会社 | Incoming call confirming and sending method in a two-way wireless communication system, a recording medium recording an incoming call confirming and sending program in the two-way wireless communication system, and a two-way wireless communication system and a base station used in the two-way wireless communication system |
| US6393008B1 (en) * | 1997-12-23 | 2002-05-21 | Nokia Movile Phones Ltd. | Control structures for contention-based packet data services in wideband CDMA |
| US6266330B1 (en) * | 1998-01-22 | 2001-07-24 | Nokia Mobile Phones Limited | Dynamic allocation of radio capacity in TDMA system |
| US6389008B1 (en) * | 1998-12-21 | 2002-05-14 | Telefonaktiebolaget L M Ericsson (Publ) | Integrated radio telecommunications network and method of interworking an ANSI-41 network and the general packet radio service (GPRS) |
| US6438370B1 (en) * | 1998-06-16 | 2002-08-20 | Nokia Telecommunications, Oy | Location update method and inter core network entity handover method |
| KR100429182B1 (en) * | 1998-09-07 | 2004-06-16 | 엘지전자 주식회사 | Method of Realizing Mobile Communication Packet Data Network in the Non-ATM Backbone Network |
| EP0996295A1 (en) * | 1998-10-22 | 2000-04-26 | Telefonaktiebolaget Lm Ericsson | Mobile communication system and alternative network gateway unit for processing a call |
| KR20000032728A (en) * | 1998-11-17 | 2000-06-15 | 서평원 | Method for assigning channel when communicating data in wide band wireless multimedia communication system |
| US6434140B1 (en) * | 1998-12-04 | 2002-08-13 | Nortel Networks Limited | System and method for implementing XoIP over ANSI-136-A circuit/switched/packet-switched mobile communications networks |
| US7502339B1 (en) * | 1999-06-21 | 2009-03-10 | Nokia Telecommunications Oyj | Mobility within a packet-switched telephony network |
| FI109508B (en) * | 1999-09-28 | 2002-08-15 | Nokia Corp | Method of allocating transmission channels in an Abis interface in a packet cellular radio network and network portion of a packet cellular radio network |
| US6678526B1 (en) * | 1999-09-29 | 2004-01-13 | Telefonaktiebolaget L M Ericsson (Publ) | Method and system for providing a call reservation service through a packet switched network |
| DE19956094C2 (en) * | 1999-11-22 | 2002-08-29 | Siemens Ag | Method for operating a GSM mobile radio system |
| US6920116B1 (en) * | 1999-12-16 | 2005-07-19 | Telefonaktiebolaget Ln Ericsson | System and method for automatically configuring network service entity identifiers utilizing a Gb-over-IP interface in a GPRS network |
| US7190687B1 (en) * | 2000-01-04 | 2007-03-13 | Qualcomm Incorporated | Method and apparatus for requesting point-to-point protocol (PPP) instances from a packet data services network |
| US7197017B1 (en) | 2000-01-04 | 2007-03-27 | Qualcomm, Incorporated | Method and apparatus for channel optimization during point-to-point protocol (PPP) session requests |
| EP1137296A1 (en) | 2000-03-21 | 2001-09-26 | TELEFONAKTIEBOLAGET LM ERICSSON (publ) | Method and apparatus for a cellular communication system |
| US8295269B1 (en) | 2000-04-10 | 2012-10-23 | Nokia Corporation | Technique for informing network of voice traffic |
| US7123920B1 (en) | 2000-04-10 | 2006-10-17 | Nokia Corporation | Technique for setting up calls in mobile network |
| EP1285544B1 (en) * | 2000-04-20 | 2005-11-09 | Nokia Corporation | Base station sub-system in a mobile communication network |
| EP1150523A3 (en) * | 2000-04-25 | 2002-06-12 | Lucent Technologies Inc. | Supporting IP on Abis interface |
| US6529525B1 (en) * | 2000-05-19 | 2003-03-04 | Motorola, Inc. | Method for supporting acknowledged transport layer protocols in GPRS/edge host application |
| US6678524B1 (en) * | 2000-05-31 | 2004-01-13 | Telefonaktiebolaget Lm Ericsson (Publ) | Bearer selection in a mobile communication system having both circuit-switched and packet-switched bearers |
| DE60018723T2 (en) * | 2000-06-26 | 2006-05-11 | Alcatel | Address scheme for an IP-based radio access network |
| FI20001705A (en) * | 2000-07-24 | 2002-01-25 | Nokia Networks Oy | A cleavage slip of a communications system |
| FR2812513B1 (en) * | 2000-07-28 | 2002-10-11 | Sagem | COMMUNICATION METHOD BETWEEN A BASE STATION AND A MOBILE TELEPHONE AND MOBILE TELEPHONE THAT CAN BE USED TO IMPLEMENT THE METHOD |
| FI111503B (en) * | 2000-11-17 | 2003-07-31 | Nokia Corp | Sending messages in a telecommunication system comprising a packet switching radio network |
| FR2818864B1 (en) * | 2000-12-21 | 2003-04-04 | Cit Alcatel | METHOD FOR REPORTING RADIO ACCESS CAPACITY INFORMATION FROM A MOBILE STATION TO A MOBILE RADIO COMMUNICATION NETWORK IN PACKET MODE |
| WO2002079758A1 (en) * | 2001-03-29 | 2002-10-10 | Circadiant Systems, Inc. | Error function analysis of optical components with uncertainty ranges |
| GB2374762B (en) * | 2001-04-18 | 2004-10-06 | Motorola Inc | Wireless communication system, wireless communication unit and method for using a communication resource |
| EP1259090A1 (en) * | 2001-05-17 | 2002-11-20 | Siemens Aktiengesellschaft | Method for optimized allocation of resources in a wireless network |
| EP1391132B1 (en) * | 2001-05-17 | 2012-01-25 | Siemens Aktiengesellschaft | Method for optimally accessing the transmission capacity in a radio communications system |
| US7920554B2 (en) * | 2001-07-30 | 2011-04-05 | Intel Corporation | Supporting both packet and circuit-based wireless networks |
| EP1430631A4 (en) | 2001-08-23 | 2009-01-21 | Bamboo Mediacasting Ltd | Multicast transmission in packet based cellular networks |
| US7155229B2 (en) * | 2002-01-08 | 2006-12-26 | Ericsson Inc. | Distributed wireless architecture using microcast |
| CA2483595C (en) * | 2002-05-01 | 2018-08-14 | Interdigital Technology Corporation | Point to multi-point services using shared channels in wireless communication systems |
| TWI469561B (en) | 2002-05-01 | 2015-01-11 | Interdigital Tech Corp | Point to multi-point services using high speed shared channels in wireless communication systems |
| US7035645B2 (en) * | 2002-05-24 | 2006-04-25 | Lucent Technologies Inc. | Methods for mitigating impact on non-privileged users of potential resource limitations in a communication system |
| TWI321918B (en) * | 2002-08-07 | 2010-03-11 | Interdigital Tech Corp | Channel switching for support of multlmedia broadcast and multicast services |
| DE10244615B4 (en) * | 2002-09-25 | 2011-08-11 | Nokia Siemens Networks GmbH & Co. KG, 81541 | Method for allocating radio transmission resources |
| IL154739A0 (en) * | 2003-03-04 | 2003-10-31 | Bamboo Mediacasting Ltd | Segmented data delivery over non-reliable link |
| AU2003901931A0 (en) * | 2003-04-23 | 2003-05-15 | Thiss Pty Ltd | Radio network assignment and access system |
| CN1298177C (en) * | 2003-05-20 | 2007-01-31 | 中兴通讯股份有限公司 | Abis port time slot resource allocation method in universal packet radio system |
| US7107037B1 (en) * | 2003-05-23 | 2006-09-12 | Sprint Spectrum L.P. | Reserving channel elements to maximize utilization of resources and prevent blocking of calls |
| IL157885A0 (en) * | 2003-09-11 | 2004-03-28 | Bamboo Mediacasting Ltd | Iterative forward error correction |
| IL157886A0 (en) * | 2003-09-11 | 2009-02-11 | Bamboo Mediacasting Ltd | Secure multicast transmission |
| IL158158A (en) | 2003-09-29 | 2012-05-31 | Bamboo Mediacasting Ltd | Distribution of multicast data to users |
| US8547909B1 (en) * | 2004-02-27 | 2013-10-01 | Sprint Spectrum L.P. | Method and system for dynamic assignment of overhead channel group |
| US8891457B2 (en) * | 2005-12-08 | 2014-11-18 | Apple Inc. | Resource assignment systems and methods |
| US20080285496A1 (en) * | 2007-05-14 | 2008-11-20 | Bamboo Mediacasting Ltd. | Data download in wireless network |
| GB2452697A (en) | 2007-08-14 | 2009-03-18 | Nec Corp | Dynamically allocating new resources to a node provided with persistently allocated resources |
| US9119092B1 (en) | 2008-05-06 | 2015-08-25 | Sprint Spectrum L.P. | Performance based selection of channel elements for use in a wireless network |
| EP2645799B1 (en) * | 2012-03-26 | 2015-10-07 | Telefonaktiebolaget L M Ericsson (publ) | Predictive EUL scheduling based on service awareness |
| CN103636177B (en) | 2012-06-28 | 2015-02-25 | 华为技术有限公司 | Method for adjusting resource configuration, radio network controller, and base station |
| CN103906133B (en) * | 2012-12-27 | 2017-11-21 | 中国移动通信集团内蒙古有限公司 | Method and system of the balanced double frequency with station with coverage cell data service |
Family Cites Families (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5297146A (en) * | 1988-07-01 | 1994-03-22 | Kabushiki Kaisha Toshiba | Communication terminal apparatus and its control method |
| CA2063901C (en) * | 1991-03-25 | 2002-08-13 | Arunas G. Slekys | Cellular data overlay system |
| US5404392A (en) * | 1991-06-12 | 1995-04-04 | International Business Machines Corp. | Digital Cellular Overlay Network (DCON) |
| JP2643689B2 (en) * | 1991-10-21 | 1997-08-20 | 松下電器産業株式会社 | Channel allocation method in microcellular system |
| US5381471A (en) * | 1993-01-29 | 1995-01-10 | At&T Corp. | Centralized service circuit deployment |
| FI97517C (en) * | 1993-09-06 | 1996-12-27 | Nokia Mobile Phones Ltd | Packet data transmission in a digital cellular network |
| US5832384A (en) * | 1993-11-12 | 1998-11-03 | Balachandran; Kumar | Method and apparatus for frequency agility in a communication system |
| FI114178B (en) * | 1995-01-09 | 2004-08-31 | Nokia Corp | Dynamic allocation of radio capacity in a TDMA system |
| CA2167428A1 (en) * | 1995-01-17 | 1996-07-18 | Bhanu Durvasula | Method and apparatus for allocating channels in a cellular system |
| US5561843A (en) * | 1995-03-21 | 1996-10-01 | Northern Telecom Limited | Mobile radio communications system |
| US5708974A (en) * | 1995-09-29 | 1998-01-13 | Telefonaktiebolaget Lm Ericsson | Method of allocating resources efficiently in a system which does not permit switching in real time |
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1998
- 1998-04-30 US US09/069,939 patent/US5978368A/en not_active Expired - Lifetime
-
1999
- 1999-04-16 BR BR9910067-3A patent/BR9910067A/en not_active IP Right Cessation
- 1999-04-16 WO PCT/SE1999/000610 patent/WO1999057924A1/en active Application Filing
- 1999-04-16 DE DE19983154T patent/DE19983154B4/en not_active Expired - Fee Related
- 1999-04-16 AU AU42983/99A patent/AU4298399A/en not_active Abandoned
- 1999-04-16 GB GB0026383A patent/GB2354136B/en not_active Expired - Fee Related
- 1999-04-16 CA CA002330845A patent/CA2330845A1/en not_active Abandoned
- 1999-04-16 CN CNB998081973A patent/CN1270554C/en not_active Expired - Fee Related
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| US5978368A (en) | 1999-11-02 |
| AU4298399A (en) | 1999-11-23 |
| DE19983154B4 (en) | 2010-04-08 |
| GB2354136B (en) | 2003-04-23 |
| DE19983154T1 (en) | 2001-05-17 |
| CN1270554C (en) | 2006-08-16 |
| BR9910067A (en) | 2000-12-26 |
| GB0026383D0 (en) | 2000-12-13 |
| GB2354136A (en) | 2001-03-14 |
| CN1308818A (en) | 2001-08-15 |
| WO1999057924A1 (en) | 1999-11-11 |
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| EEER | Examination request | ||
| FZDE | Discontinued |