WO1997035387A1 - Method and apparatus for cordless infrared communication - Google Patents
Method and apparatus for cordless infrared communication Download PDFInfo
- Publication number
- WO1997035387A1 WO1997035387A1 PCT/US1997/004318 US9704318W WO9735387A1 WO 1997035387 A1 WO1997035387 A1 WO 1997035387A1 US 9704318 W US9704318 W US 9704318W WO 9735387 A1 WO9735387 A1 WO 9735387A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- signals
- modules
- base unit
- infrared
- signal
- Prior art date
Links
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B10/00—Transmission systems employing electromagnetic waves other than radio-waves, e.g. infrared, visible or ultraviolet light, or employing corpuscular radiation, e.g. quantum communication
- H04B10/11—Arrangements specific to free-space transmission, i.e. transmission through air or vacuum
- H04B10/114—Indoor or close-range type systems
- H04B10/1149—Arrangements for indoor wireless networking of information
Definitions
- This invention generally relates to a method and apparatus for communicating from a base unit to a plurality of portable infrared units located randomly throughout a building while using established communication protocols. More specifically this invention relates to a digital communication method and system for enabling a central control connected to telephone lines to communicate with a plurality of portable infrared devices, such as handsets and the like, located within an enclosed site.
- Standard cellular systems cannot adequately serve such function because of the long distance range of cellular RF signals and the need to accommodate a large number of simultaneous communications within a relatively small volume such as a building.
- These wireless standards have been adopted so that both data and speech signals can be sent over RF frequencies between a central radio exchange and a large number of portable devices.
- These standards employ a time division multiple access/time division duplex/multiple carrier (TDMA TDD/MC) approach. More simply put, digital signals to or from the radio exchange unit are sent in time slots.
- TDMA TDD/MC time division multiple access/time division duplex/multiple carrier
- the communication thus occurs in frame signals of say twenty milliseconds long, with the time frame divided into say ten uplink or transmit slots followed by the same number of ten down link or receive slots. Each slot being one millisecond long.
- Each portable unit must respond to a signal addressed to it in one of the uplink slots in a corresponding downlink slot in the same frame signal.
- the number of simultaneous communications is limited by the number of available slots. If there are say ten slots, then for any one particular carrier frequency only ten telephone signals can be carried. In order to increase the capacity of the system additional carrier frequencies are employed typically about eight. Hence, for each cell, formed of a radio exchange unit, a total of eighty active telephone communications can be carried out.
- Infrared communication systems are well known, see for example the U.S. patents to Crimmins 4,553,267; 4,757,553; 4,977,619; 5,103,108; 5,319,191 and 5,351 ,149.
- a base unit is hard wire connected to a plurality of stationary infrared transmitter and receiver (R/T) units distributed in an enclosure.
- R/T stationary infrared transmitter and receiver
- an infrared cordless communication method and system in accordance with the invention the channel limitations of radio frequency digital cordless systems can be avoided and a high density of portable infrared terminals can be accommodated without interference problems while using standard communication protocols for RF cordless systems.
- RT transmitting
- base unit that in turn is connected to a radio exchange unit for RF cordless systems.
- the RT modules are located to cover a desired area so that portable IR units in the building area can communicate through the RT modules with telephone lines connected to the radio exchange unit.
- the signal paths delays between the base unit and the RT modules are effectively made substantially the same for at least those RT modules that are in each other's vicinity. As a result infrared carrier frequencies incident upon any one portable unit from several nearby RT modules will not be significantly out of phase.
- the signal path delays can be equalized by employing similar cable lengths between the base unit and nearby RT modules.
- signal path delays are equalized by introducing appropnate delays of signals sent to and from the base unit and the RT modules. Signal path lengths are continually monitored and appropriate delays are automatically introduced for each signal path.
- one or more RT modules may be sending signals to a base unit from the same portable unit
- another aspect of the invention is the selection of the best portable signal. For example, when a portable unit responds in a time slot, several RT modules may receive the signal and forward it to the base unit. As a result the base unit, prior to actually receiving the signal from the RT's, makes a selection of the best signal based upon information sent to it by the RT modules. This selection is made for each slot transmission and enables the best signal to be used for the communication even while the portable unit is moving between RT modules in the building area.
- the number of infrared portable units that can be connected by a base unit can be made quite flexible and much higher than the number that is available using conventional RF techniques.
- This can be done by the use of hubs each of which can be connected to a number of infrared RT modules. For example, if a base unit has sixteen ports, each of which could be connected to RT modules the number of RT modules can be increased by the use of hubs.
- Each hub having, for example, sixteen module connectable ports so that a total of 256 RT modules can communicate with a single base unit. As a result one base unit can serve a high density of portable users.
- Each base unit can be considered as a separate cell designed to serve a particular area and yet be able to establish cordless digital telephone communication in a flexible manner.
- a number of different cells can be arranged, as the circumstances may require, with each cell enabling a separate telephone communication with a number of different infrared portable units.
- Figure 1 is a schematic block diagram representation of one infrared communication system in accordance with the invention
- Figure 1a is a partial representational view of a cable used in the IR system of Figure 1 ;
- Figure 2 is a schematic representation of a building to illustrate the advantages of the infrared communication system in accordance with the invention
- Figure 3 is a schematic representation of a conventional cordless RF communication system
- Figure 4 is schematic representation of a typical signal frame used in the communication system shown in Figure 3;
- Figure 4a is a timing diagram for illustrating the flow of signals in an IR communication system in accordance with the invention.
- FIG. 5 is a block diagram of a base unit employed in the infrared communication system shown in Figure 1;
- Figure 6 is a partial block diagram view of the infrared communication system shown in Figure 1 ;
- Figure 7 is a partial block diagram view of a portion of the infrared communication system used to select the optimum signal from the infrared RT modules;
- Figure 8 is a block diagram for generating timing signals used in the system of Figure 1;
- Figure 9A is a timing diagram of certain signals generated in the infrared communication system of Figure 1 ;
- Figure 9B is a timing diagram of certain signals generated during a receive slot when signals from a portable unit are sent by an RT module back to the base unit;
- Figure 9C is a timing diagram on an expanded time scale of the leading portion of a receive slot
- Figure 10A is a block diagram view of an infrared RT module used in accordance with the invention.
- FIG. 10B is a more detailed block diagram view of an RT module used in accordance with the invention.
- Figure 11 is a state diagram of an RT module used in the IR communi ⁇ cation system of Figure 1 ;
- Figure 12 is a block diagram view of an infrared portable unit used with the infrared communication system of this invention.
- Figure 13 is a system block diagram view of an alternate embodiment for an infrared communication system in accordance with the invention.
- FIG. 14 is a block diagram view of a hub used in an infrared communication system in accordance with the invention.
- Figure 15 is a block diagram, view of a simplified base unit for use with a communication system as shown in Figure 13.
- Figure 16 is a block diagram view of a simplified RT module for use with the communication system as shown in Figures 13 and 14; and Figure 17 is a schematic block diagram view of a network at the base unit shown in Figure 15 and is used to determine the best IR signal received at RT modules from portable devices.
- an infrared (IR) communication system 20 in accordance with the invention is shown connected to telephone lines 22 through a radio exchange 24.
- the IR system 20 is made to operate with the protocols associated with a standard RF cordless communication system known as the CT3 system.
- CT3 system a standard RF cordless communication system
- other systems such as compatible with the DECT protocol can be used.
- cables crossed by a slash line and a number next to that line means the use of a number of paths in that cable equal to the number next to the slash.
- Some cables such as 54 have four twisted pairs indicating the use of four transmission paths though eight conductors may be involved. In other lines sixteen paths are used with as many conductors.
- Also used herein is the practice of identifying items that are alike with the same number but with a decimal point and a number on the right of it to indicate particular ones of the items.
- the CT3 RF cordless standard employs a DECT type digital communi- cation wherein a TDMA/TDD/MC system operates just below 2 GHz.
- the CT3 system employs a 16 ms frame cycle 26 formed of a transmit segment 28 using 8 transmit slots 30 and a receive segment 32 using 8 receive slots 34.
- Each slot 30 or 34 is one millisecond in duration and a transmission within a slot includes 480 data bits formed of fields as illustrated at 36.
- the system operates in such a way that when, for example, a transmission from radio exchange unit 24 arises by virtue of an incoming telephone call on an incoming line 22, a digital signal is placed in one of the outgoing or transmit slots 30 and is followed by a response in the same frame in a receive slot 34.
- different frame lengths can be employed in different protocols as for example the ten slots used in the DECT system as described in the above mentioned IEEE article.
- the infrared system 20 for a cell 21.1 is formed of a base unit 40 which communicates with a CT3 or DECT type controller or interface 42 to enable digital communication with system 20.
- System 20 further may be composed of a number of hubs 44, which in turn are connected to one or more stationary infrared receiver/transmit (RT) modules 46 distributed in a building.
- the RT modules 46 in turn communicate with portable or cordless infrared devices 48 such as telephones.
- the RT modules 46 may be directly connected to the base unit 40 such as is shown for modules 46.17- 46.24.
- hubs 44 and the distribution of RT modules 46 can be as varied as the circumstance require, it being understood that the distribution and connections of RT modules in Figure 1 is for illustration purposes and is not intended to be required.
- the base unit 40 is connected to RT modules and to hubs 44 by way of twisted pair cables 52.
- Each cable 52 as shown in Figure 1a is formed of four twisted pairs of conductors 54.1-54.4 to respectively conduct distinct signals, namely, the transmit segment Tx, 28 of the frame signal 26 on pair 54.1 , the receive segment Rx, 32, on pair 54.2, a signal to noise ratio signal on pair 54.3 and electrical power for the RT modules 46 on pair 54.4.
- the arrows are indicative of the direction of signal flow on the respective pairs 54.
- the use of a double headed arrow on signal pair 54.1 indicates that this pair is used to transfer signals in both directions, but at different times as will be further explained.
- the Telco lines 22 enter a radio exchange 24 and are passed on by it to RF base cells 60 connected to antennas 62, The digital RF signals are sent to portable devices 64 which can roam over a large area within or outside a building while maintaining contact for communication with the radio exchange 24.
- any one RF cell is illustrated in Figure 2 wherein a building 66 of many floors 68 is shown.
- Any one base cell 60 such as cell 60.1 tends to range over a volume of space that encompasses a number of floors as illustrated with the dashed line 70.
- the number of portable devices that can be distributed or used within the cell is limited by the number of available slots in the DECT or CT3 type communication system. This then employs multiple carriers to increase the available channels, but because of the spectrum allocation limitations still may be inadequate for accommodating the required number of portable devices 64.
- each floor can be provided with one or more hubs 44 and as a result many RT modules 46 can be made available to accommo- date as many infrared portable devices 48 as are needed. Signals between a hub 44 and a portable device 48 do not spill over onto unwanted areas, such as separate floors and thus security and interference problems are avoided.
- signals are transferred between the radio exchange and the portable units 48 in compliance with the established protocol by inserting special signals and using signal lines for particular purposes as depicted in the view of Figure 4a.
- Figure 4 has for illustrative purposes transmissions occurring during slots 30.1 , 30.5 (indicated by check marks) and as a result response signals in receive slots 34.1 and 34.5 also evidenced by the check marks in these slots.
- system 20 inserts a delay 71 to assure that the transmissions destined for nearby RT modules 46 arrive at the same time.
- a base unit 40 is shown connected by cable 52.1 and 52.2 of different lengths to RT modules 46.1 and 46.2 respec ⁇ tively.
- the IR carrier energy arriving at a portable unit 48.1 may include portions from both nearby RT modules and differ in phase, depending upon the different signal path lengths from the base unit 40. If the signals are about 180 degrees out of phase as shown at 67, the net effect at a portable unit 48 is a cancellation of IR carrier signals, in effect a null, and thus adversely impacts communication with that portable unit.
- the signal path lengths from the base unit to RT modules 46 which are near each other be made about the same.
- the inserted delays are selected so that transmissions from a base unit during any one slot arrive at all the RT modules 46 at the same time.
- the delays are first automatically determined as shown in Figure 4a during those intervals such as 72.2 and 72.6 when slots, such as 30.2 and 30.6, do not require a transmission. Delays are measured by sending a pulse signal 73 from the base unit 40 to each of the RT modules 46 and measuring the time for a return signal 74 to arrive from that module. Measuring of delays need not be done every time there is no transmission. Hence, a counter is employed to allow measuring of delays at some increased time interval.
- IR system 20 Another feature of IR system 20 arises from the possibility that more than one RT module 46 responds to the return transmission from a portable device 48. IR system 20 selects the best RT module signal just prior to the occurrence of the return transmission. As shown in Figure 7 an RT module 46 includes a photo detector 75 responsive to IR signals from portable devices 48. The output of the detector 75, after amplification, is passed onto an analog to digital converter 76 to produce a digital Rx receive signal for return to the base unit 40.
- a signal strength indication is generated at the output of a comparator 77 after it has compared the output from the photo detector 75 with a squelch level signal from a squelch generator 78.
- the signal strength indication is also converted to digital form with a fast A D converter 79.
- This A/D converter generates a three bit signal strength signal with each bit placed on a separate line 54 for return to the base unit 40.
- the fast analog to digital conversion of the signal strength is sent at 79a to the base unit 40 before it receives the Rx receive slot signal 34.
- a selection of the strongest signal is then made at 81a. This is done at 81 shown in Figure 7, and used at 83 to pass the best Rx signal on to the radio exchange unit 24. This selection of the strongest signal is also used to choose a best RSSI signal.
- An RSSI signal for each receive slot 34 may be required by the CT3 or DECT protocols and represents the strength of the received portable IR signal at an RT module 46.
- a base unit 40 in accordance with the invention is shown in further detail.
- Signals to and from a conven- tional CT3 radio exchange interface 42 occur on lines 90.1-90.5. These signals are respectively a serial digital transmission signal T x , on line 90.1 ; a logic control signal T/R on line 90.2; a frame logic signal on line 90.3; a re ⁇ ceived signal R x on line 90.4; and a signal strength indication RSSI signal on line 90.5.
- the transmission signal T x destined for all RT modules in a cell 21 , is applied to an FM modulator 91 wherein a digital voltage controlled oscillator, in response to an input from an oscillator 92 at 55 MHz, produces zeroes represented by a frequency at 3.429 MHz and ones at a frequency of 4.571 MHz. Different frequencies can of course be employed.
- the output 93 from the modulator 91 is applied to an electronically controlled switch 94 and then through a multiplexer 95 to a delay network 96.
- the delay network 96 delays the transmission signal T x by an amount that is sufficient to assure that transmissions, from at least those RT modules 46 which are near each other, occur at essentially the same time. For simplicity the delays are selected so that transmissions from RT modules 46 during any one slot occur essentially at the same time.
- the transmission signal T ⁇ l destined for each individual RT module 46 is delayed a particular amount, depending upon the length of the cable connecting that module to the base unit 40.
- the delays are selected so that they are equivalent to the delay caused by the longest cable length involved.
- the delayed T x signals are then passed through a multiplexer 97 onto the transmitter lines 54.1 of the various cables 52 leading to the hubs 44 and RT modules 46. This process is continued for each of the T x signals in the respective transmission slots 30 of a frame signal 26.
- the lines 54 are twisted pairs and are driven by amplifiers 98a and terminated with receivers 98b. These amplifiers and receivers enable a tristate condition on the lines 54 so as to preserve power when no transmissions are to occur and permit two way signal flow when this is needed as for the transmission lines 54.1.
- the tristate condition is regulated by signals generated from a controller 114 as hereafter described.
- each of the RT modules 46 which had passed on a T x signal to the portable devices 48 returns a receive signal R x to the base unit 40 in the slot which corresponds to the transmission slot in which the T x signal being responded to was located.
- a signal indicative of the signal strength of the infrared signal received at the RT modules, from the portable devices 48 sending a response is transmitted to the base unit as an S/N signal.
- the receive signals R x from the respective RT modules and hubs are passed through the delay network 96 to undergo delays of the same duration as the delays imparted to the corresponding transmission signals T x .
- the sixteen receive signals R x on cable lines 54.2 are, therefore, coupled to the input side of the multiplexer 95 and then passed through the delay network 96 to essentially arrive simulta ⁇ neously at the output lines 98 of multiplexer 97.
- the base unit 40 includes a network 100 to select that signal representative of the best available R x signal.
- the R x signals are applied to a multiplexer 101 where the best receive R x signal is selected and placed on line 90.4 leading to the interface 42.
- the best R x signal is selected with control signals on lines 98 derived from a digital magnitude comparator 102.
- the latter comparator 102 compares signals on input lines repre ⁇ sentative of the signal to noise ratios of the infrared inputs to the RT modules as previously described with reference to signals 79a and 81a in Figure 4a. As explained, this comparison is done at a time preferably just prior to the applicable receive slot.
- the selection of the best receive signal R x therefore, occurs during a very brief interval between slots 30 as will be further explained.
- the control signals on lines 99 are also applied to a multiplexer 104 whose inputs are connected to the respective signal strength lines 54.3 from the various hubs 44 and RT modules 46.
- the best signal strength signal is selected for each slot 30 and stored in a register 106 with a clock signal presented on the T x1 . l6 lines 54.1 from the RT modules 46.
- the clock signal is presented on the output line 103 of a multiplexer 105 whose input lines connected to lines 54.1.
- the value of the signal in the register 106 is converted by a digital to analog converter 108 to an analog signal and presented on line 90.5 as the RSSI signal associated with the slot 34 to which the receive signal R x relates.
- the identification of the best R x signal with control lines 99 can be used as an indication of the location of the portable which was the source of the receive signal.
- the control signals on lines 99 identify the port where the receive signals arrived and are stored in a register 107.
- the port identification signals are clocked out onto the RSSI line 90.5 with the clock signals on line 103 from multiplexer 105.
- sequencer 110 Control over the operation of the base unit 40 and the functions of the above described networks is obtained with a sequencer 110.
- This may be in the form of a micro processor with appropriate programming. However, the speed with which the required signals have to occur makes it desirable to employ discrete circuits.
- the sequencer 110 produces appropriate control signals with which the various functions of the base unit 40 accomplishes its tasks.
- the sequencer 110 in response to the T/R and frame signals, on lines 90.2 and 90.3 respectively, produces timing signals such as a sync signal on line 112.1 , a transmit enable signal on line 112.6, a transmit or receive selection signal on lines 112.2 and 112.7 to set up the appropriate mode in the multiplexers 95 and 97 respectively and a calibration enable signal on lines 112.3.
- the sequencer generates tap register enable signals on lines 112.4 and a best receive selection signal on line 112.5.
- the sequencer includes a calibration controller 114 and a 12 MHz clock 115 with which the electrical delays produced by the cable lengths may be repetitively measured and then used to set the appropriate delays. Selected ones of these signals also control the tristate conditions of several amplifiers 98a and receivers 98b employed at the base unit 40 to drive the lines 54.
- a frame sync signal as appears on line 90.3 in Figure 5 is a square wave 130.1, see Figure 9A, having equal transmission and receive segments 132 and 134 corre- sponding to the transmission and receive segments 28 and 32 shown in Figure 4.
- the transition 136 from a transmit segment 132 to a receive segment 134 is a timing reference used to initiate certain timing signals as shown in Figure 8.
- the frame sync signal 130 is, therefore, connected in the sequencer 110 to a frame pulse generator 137 which causes a resetting of a fourteen bit counter 140 driven by 12 MHz clock 115.
- Certain counts achieved inside counter 140 are decoded with a comparator 141 as indicated on lines 142 with the count number placed adjacent the lines 142.
- a comparator 141 When the register is full a pulse is applied to drive a slot clock 146 and its output pulses counted in a slot counter 148.
- This circuitry thus produces timing signals on lines 142 to cause certain events to occur during a slot and to enable the slots 30 and 32 in a frame 26 to be counted.
- the numbers placed along the lines 142 signify the count in the register 140 that yields an output on that line with reference to the frame transition 136 in the frame sync signal.
- the T/R logic signal 160 on line 90.2 in Figure 5 from the radio exchange unit 24 signifies when a transmission occurs during a slot 30.
- FIG 9A an illustrative example of a T/R signal 160 is shown wherein a transmission is to occur in the first slot 30.1 and none in the subsequent slots 30.2, 30.3. and 30.4.
- the occurrence of the various timing signals on output lines 142 and obtained from the register 140 are depicted on the T/R signal line 160 as shown, with the larger counts being abbreviated as illustrated with apostrophes.
- data for transmission is sent on line 90.1 commencing with the count of 144, see Figures 8 and 9A.
- the transmission begins at a time identified also by numeral 162. Transmission ends at the end of sending a fixed number of 480 bits, as explained with reference to Figure 4, at a time identified at 164 shown in Figure 9A.
- the end of transmis- sion occurs just prior to the timing signal on line 142.5 bearing the count 11904.
- the time period following the transmission of the last bit until the next count of 144 is an interval 166 associated with time between sequential transmission slots 30.
- any signals occurring on the data line 90.1 from the radio exchange 24 can be construed as noise and transmissions can and are inserted by the base unit 40 to the hubs 44 and RT modules 46 as well as received from these devices for the operation of the communication system
- One calibration mode of operation that is preparatory for the functioning of the IR communication system involves an automatic determination of the length of delay needed to assure that adjacent or nearby RT modules 46 are activated for transmissions at substantially the same time.
- This employs a transmission of a special sync signal 170, see Figure 9, commencing on a line 172, see Figure 5.
- the sync signal is passed through the multiplexer 95, and delay measuring and applying network 96 and sent out on an output line 54.1 of a cable 52 to a particular RT module 46.
- the sync signal is recognized by virtue of its unique duration by the RT module 46 to which it is sent.
- the RT module Upon recognition of the sync signal 170 the RT module returns a response 176, see Figure 9A, to the base unit 40 on the same transmission line 54.1 on which the sync signal is sent.
- the response 176 is initiated upon detection of the sync signal at the RT module 46.
- the arrival of the response 176 at the base unit 40 is detected by the delay measuring network 96.
- the time of the arrival of the response 176 is indicative of the roundtrip travel interval 178 of signals along the cable 52.
- the base unit 40 measures the delay imparted by the length of the cable 54 connecting the base unit 40 to the RT module 46 by counting the pulses from oscillator 92, see Figure 5, in a shift register 180 associated with the particular RT module 46. These pulses are counted starting from the time that the sync signal 170 is first sent until the arrival of the response 176. The count accumulated in the register 180 is then representative of twice the length of the cable 52 between the base unit 40 and an RT module 46. Since the count represents the roundtrip distance, the count is divided by two, obtained with a simple shift of the count in the register 180, and then stored in a tap register 182 as equivalent to the required one way trip delay.
- the delay count in a tap register 182 is so coupled to an associated shift register 180 that the delay count determines where along the shift register 180 a transmission of data to is to begin entering the shift register 180. In this manner a small delay count, representative of a relatively long cable 52, causes data to be entered towards the input end of a shift register 180. A large count on the other hand causes data to be entered towards the output end of a shift register 180.
- the process for determining the cable delays is initially carried out for each of the RT modules 46 as the system is started up. Once the system is operational the delay calibration is continued on a repetitive basis depending upon the traffic of data along the cables 52, i.e. the availability of a transmis- sion slot 30.
- the sequencer 110 provides the appropriate timing signals for the system with the calibration controller 114. This regulates, with the T/R line 90.2 and the frame sync line 90.3 from the radio exchange interface 42, and produces signals for enabling transmissions in a slot. It also generates the control signals on lines 112 needed to establish a delay calibration for a slot if this has not been done within a predetermined time or after a certain number of transmissions. This circuitry needed to generate signals can be produced with an array logic or such other suitable programmed micropro ⁇ cessor.
- IR communication system 20 signals representative of data or voice information is sent in slots 30 to all of the RT modules 46 either directly from the base unit 40 or through a hub 42.
- the slot signal assigned to a particular portable unit 48 is so loaded into a shift register 180 associated with a particular RT module 46 as to be delayed in time in proportion to the delay previously measured for the associated cable 52 and stored in the associated tap register 182.
- the sequencer 110 Since during transmission each slot signal is sent to all of the RT modules 46 in a cell, the sequencer 110 enables the loading of each transmission slot signal into all of the shift registers 180. Signals are shifted out of the registers 180 onto the output lines 54.1 in each cable 52 to arrive substantially at the same time at the RT modules 46.
- the response is generated at a time dependent on the slot of the transmission signal that caused the response. This is done in a manner as is well known in CT3 or DECT type communication systems. Suffice it to note that the return signals, known and described herein as receive signals, are preferably placed in the receive slot 34, see Figure 4, which corresponds to the position of the transmission slot 30 in the transmission cycle 28.
- a single cell contains a large number of possible IR receivers in the form of RT modules 46. Since several RT modules 46 near a portable unit 48 are likely to generate receive signals it is desired to provide the radio exchange unit 24 with the best signal at one of these RT modules. The best signal is to be selected for each receive signal slot 34. The best signal can then also be made available as an RSSI (receiver signal strength) signal for transfer to the radio exchange unit 24 as represen ⁇ tative of the signal strength at the receiver from the respective portable unit from where the signal originates.
- RSSI receiver signal strength
- a best signal selection is done just prior to the start of each active receive slot 34.
- the receive segment 134 of a frame signal 130.2 is shown in synchronized relationship with the frame signal 130.1 shown above it for the transmission cycle.
- Several receive slots 34 are illustrated and in response to the occurrence of a transmission in transmission slot 30.1 a response is to be sent back in slot 34.1.
- an RT module 46 when an RT module 46 detects the receive slot sync signal 184 the RT module 46 samples the received IR signal strength. The sampled value is then immediately transmitted to the base unit 40 before beginning a transmission of a signal in a receive slot 34. This can be understood with reference to the timing diagrams of Figures 9B and 9C.
- A/D conversion occurs after the start at 186 of the portable IR carrier for a receive slot transmission and allowing at 187 for settling of the output 188 from an amplitude detection circuit, not shown, for the IR signal.
- FIG. 10B shows the circuitry used to provide the described functions for an RT module 46.
- An IR transmitter 200 for sending IR signals to portable units 48 and an IR detector 75 for detecting responses from portable units are used.
- the RT modules 46 include a programmable array logic (PAL) and other appropriate circuits 204 (enclosed by the dashed line in Figure 10B) for processing inputs and outputs.
- PAL programmable array logic
- the transmission inputs on line 54.1 from the base unit 40 or a hub 44 are passed on to a modulator 206 and amplifier 208 for activating the IR transmitter 200.
- the transmitter 200 may use a suitable number of IR generating diodes 200 in a manner as is well known in the art to produce the desired IR signal output to the portable units 48.
- An amplifier 210 and a demodulator 212 are used to respond to IR signals from the portable units 48 to produce electrical signals for transmis ⁇ sion to the base unit 40, either directly or through a hub 44.
- P.A.L circuit 204 employs an external clock 214 which drives a counter
- a carrier detection circuit 218 is used to detect the arrival of a transmission on the transmit line 54.1 and apply a signal to that effect on line 220.
- the transmit line 54.1 is also directly applied to circuit 204 to enable it to detect appropriate data and logic conditions.
- a logic network 222 detect the presence of a calibration sync pulse 176, see Figure 9A.
- the logic circuit 222 generates a response signal on output line 224 which is returned to the base unit 40 via a multiplexer 226.2 for the previously described cable delay calibration.
- the fast three bit A/D converter 79 which is controlled by a signal on line 227 from the P.AL. circuit 204 has outputs 228.1-228.3 respectively applied to multiplexers 226.1-226.3.
- the operations of the multiplexers 226 are controlled with signals on lines 230.1-3 from circuit 204.
- the various tristate conditions of amplifiers 232.1-4 driving the lines 54.1-3 in cable 52 are also controlled with signals on lines 234.1-3 from circuit 204.
- the programming and operation of the P.A.L circuit 204 can be best understood from the self-explanatory state diagram 250 in Figure 11 in conjunction with the counts as illustrated on top of the figure.
- the presence of a transmitter carrier on a transmission input line 54.1 from the base unit 40 is awaited at 256.
- an idle mode is entered at 258.
- a sync pulse is pres- ent as detected at 260 either the occurrence of a calibration mode sync occurred or a receiver mode sync pulse has been detected.
- a return sync pulse is generated at 266 and returned to the base unit 40 and the state is returned to step 258.
- control is shifted to step 270.
- a fast abbreviated (three bit) A/D conversion is carried out as previously described at 272 followed by a full slower A/D conversion at 274 and sending of signals for a receive slot at 276 as received from a portable device 48.
- the portable unit 48 shown in Figure 12 also includes an IR transmitter 320 and an IR detector 322 respectively connected to a modulator 324 and demodulator 326.
- a logic circuit 328 is used to handle the digital traffic and convert the signals to appropriate format for use by the conventional handset 330.
- a key board 332 such as used with conventional handsets is available to initiate calls.
- the logic network 328 provides the functions and operations like those in an RF portable unit and need, therefore, not be further described.
- Figure 14 shows a hub 44, which is very similar to a base unit 40. For that reason circuits and lines having similar functions have the same numbers as described with reference to the base unit 40. A variation from the base unit occurs at the input of a hub where the incoming connections are made with a cable 52 having the T x , 54.1, R x , 54.2, and S/N, 54.3 lines as previously described. The resulting inputs correspond to the lines described with reference to Figure 5 and have been correspondingly numbered 90.1', 90.4' and 90.5'.
- the slot sync 90.2' and frame sync 90.3' are derived from the input line 90.1' with a sync detector 370. This detector recognizes when a calibration sync pulse is being sent and responds with a return signal on line 372.
- FIG. 13 shows an alternative IR system 20' in accordance with the invention.
- the cables 52 connecting a base unit 40 to nearby RT modules 46 are made all essentially the same in length. This requires that the shorter cables 52 include extra lengths that are wound into coils 350. The cable lengths need not be the same for those RT modules 46 not sufficiently close or separated by a wall and thus not likely to communicate with the same portable device 48 at the same time.
- the system 20' may use a simplified base unit 360 as shown in Figure
- Base unit 360 employs a logic network 362 which responds to the incoming frame sync signal on line 90.3 to enable an AND gate 364 during the transmission segment 28 of the operation.
- the transmission from the base unit 20' is passed directly on to the cables 52 through appropriate drivers 98a.
- the R x signals from the various RT modules 46' are passed through a best signal selection network 366.
- the circuits and networks described with reference to base unit 360 can be implemented by a microprocessor instead of with discrete circuitry as shown. The operation of these networks can be best explained with reference to the modified RT module 46' as shown in Figure 16 and wherein like numerals designate like components as previously described.
- the demodulated IR signal from a portable device is applied as an R x signal to an AND gate 380.
- a signal representative of the received signal strength is applied on line 75a to squelch type networks 78 and 382. If the IR signal level is very high, thus representing a high quality signal, a comparator 384 detects that the signal exceeds an adjustable threshold value as set at 386. The output is a high quality signal on line 388 which is applied to the signal to noise ratio line 54.3 from this RT module 46' to the base unit 360.
- the AND gate 380 is enabled and the digital R x signal is passed on to the R x data output line 54.2 to the base unit 360.
- the signal lines 54 identified in Figure 17 represent the same signals as on lines 54 except that they lines are single conductors from the outputs of receivers, not shown, connected to lines 54 from the RT modules 46'.
- a priority network 394 is used to first assure that the R x signal having a high quality level associated with it is detected with network 400 and thus first passed on to the radio exchange 24 via line 90.4.
- a second priority network 402 is used to pass an R x signal onto line 90.2 as long as one of the signals from the RT modules 46' exceeds the adequate signal threshold level set by networks 390 ( Figure 16).
- a final decision network 404 is used to combine the outputs from the networks 400 and 402 to present on line 90.4 the R x signal for the radio exchange 24.
- the best signal selection works by coupling the high quality signals on lines 54.3', the S/N signals, from sixteen RT modules 46' to AND gates 406.1-16.
- the RT module 46' which could be the one connected to port 1 of the base unit 360, has its S/N line 54.3' coupled to the input of AND gate 406.1 together with a reference signal on line 408 representing an inactive signal level. If there is a high quality signal level present on line 54.3' leading to AND gate 406.1 then its output 412.1 is enabled and in turn enables the AND gate 410.1. This allows data from the RT module 46' on line 54.2' to be passed on to the OR gate 414 in network 404.
- a data signal having the next acceptable signal level is passed on to network 404 by the selection network 402.
- This process involves the generation of an adequate level signal Q on lines 420.1-16.
- Q signals are derived from the combination of a lack of signals on lines 54.3' and the presence of data (R x ) signals on any one of the lines 54.2'.
- the selection of the best R x signal by circuit 402 employs a similar technique as described for circuit 400.
- the first Q signal on line 430 is applied through an inverter to an AND gate 432.1 together with the data signals on line 54.2'. If there is an adequate signal level then this is passed onto network 404 via OR gate 434 and thus through AND gate 420 to the output line 90.4 through OR gate 436. If the adequate signal level occurs from any other RT module 46', the next highest data signal in the chain of priority is passed on.
Abstract
Description
Claims
Priority Applications (5)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP9533627A JP2000507058A (en) | 1996-03-22 | 1997-03-19 | Method and apparatus for cordless infrared communication |
CA002249450A CA2249450C (en) | 1996-03-22 | 1997-03-19 | Method and apparatus for cordless infrared communication |
EP97916058A EP0894374A1 (en) | 1996-03-22 | 1997-03-19 | Method and apparatus for cordless infrared communication |
IL12628897A IL126288A0 (en) | 1996-03-22 | 1997-03-19 | Method and apparatus for cordless infrared communication |
AU23326/97A AU714753B2 (en) | 1996-03-22 | 1997-03-19 | Method and apparatus for cordless infrared communication |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US08/624,852 | 1996-03-22 | ||
US08/624,852 US5867292A (en) | 1996-03-22 | 1996-03-22 | Method and apparatus for cordless infrared communication |
Publications (1)
Publication Number | Publication Date |
---|---|
WO1997035387A1 true WO1997035387A1 (en) | 1997-09-25 |
Family
ID=24503596
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/US1997/004318 WO1997035387A1 (en) | 1996-03-22 | 1997-03-19 | Method and apparatus for cordless infrared communication |
Country Status (8)
Country | Link |
---|---|
US (3) | US5867292A (en) |
EP (1) | EP0894374A1 (en) |
JP (1) | JP2000507058A (en) |
CN (1) | CN1220789A (en) |
AU (1) | AU714753B2 (en) |
CA (1) | CA2249450C (en) |
IL (1) | IL126288A0 (en) |
WO (1) | WO1997035387A1 (en) |
Cited By (163)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0952689A2 (en) * | 1998-04-22 | 1999-10-27 | Sony Corporation | Transmitter, receiver and distribution medium for an infrared communication system |
US9154966B2 (en) | 2013-11-06 | 2015-10-06 | At&T Intellectual Property I, Lp | Surface-wave communications and methods thereof |
US9209902B2 (en) | 2013-12-10 | 2015-12-08 | At&T Intellectual Property I, L.P. | Quasi-optical coupler |
US9312919B1 (en) | 2014-10-21 | 2016-04-12 | At&T Intellectual Property I, Lp | Transmission device with impairment compensation and methods for use therewith |
US9461706B1 (en) | 2015-07-31 | 2016-10-04 | At&T Intellectual Property I, Lp | Method and apparatus for exchanging communication signals |
US9490869B1 (en) | 2015-05-14 | 2016-11-08 | At&T Intellectual Property I, L.P. | Transmission medium having multiple cores and methods for use therewith |
US9503189B2 (en) | 2014-10-10 | 2016-11-22 | At&T Intellectual Property I, L.P. | Method and apparatus for arranging communication sessions in a communication system |
US9509415B1 (en) | 2015-06-25 | 2016-11-29 | At&T Intellectual Property I, L.P. | Methods and apparatus for inducing a fundamental wave mode on a transmission medium |
US9520945B2 (en) | 2014-10-21 | 2016-12-13 | At&T Intellectual Property I, L.P. | Apparatus for providing communication services and methods thereof |
US9525210B2 (en) | 2014-10-21 | 2016-12-20 | At&T Intellectual Property I, L.P. | Guided-wave transmission device with non-fundamental mode propagation and methods for use therewith |
US9525524B2 (en) | 2013-05-31 | 2016-12-20 | At&T Intellectual Property I, L.P. | Remote distributed antenna system |
US9531427B2 (en) | 2014-11-20 | 2016-12-27 | At&T Intellectual Property I, L.P. | Transmission device with mode division multiplexing and methods for use therewith |
US9564947B2 (en) | 2014-10-21 | 2017-02-07 | At&T Intellectual Property I, L.P. | Guided-wave transmission device with diversity and methods for use therewith |
US9577306B2 (en) | 2014-10-21 | 2017-02-21 | At&T Intellectual Property I, L.P. | Guided-wave transmission device and methods for use therewith |
US9608692B2 (en) | 2015-06-11 | 2017-03-28 | At&T Intellectual Property I, L.P. | Repeater and methods for use therewith |
US9608740B2 (en) | 2015-07-15 | 2017-03-28 | At&T Intellectual Property I, L.P. | Method and apparatus for launching a wave mode that mitigates interference |
US9615269B2 (en) | 2014-10-02 | 2017-04-04 | At&T Intellectual Property I, L.P. | Method and apparatus that provides fault tolerance in a communication network |
US9628116B2 (en) | 2015-07-14 | 2017-04-18 | At&T Intellectual Property I, L.P. | Apparatus and methods for transmitting wireless signals |
US9628854B2 (en) | 2014-09-29 | 2017-04-18 | At&T Intellectual Property I, L.P. | Method and apparatus for distributing content in a communication network |
US9640850B2 (en) | 2015-06-25 | 2017-05-02 | At&T Intellectual Property I, L.P. | Methods and apparatus for inducing a non-fundamental wave mode on a transmission medium |
US9654173B2 (en) | 2014-11-20 | 2017-05-16 | At&T Intellectual Property I, L.P. | Apparatus for powering a communication device and methods thereof |
US9653770B2 (en) | 2014-10-21 | 2017-05-16 | At&T Intellectual Property I, L.P. | Guided wave coupler, coupling module and methods for use therewith |
US9667317B2 (en) | 2015-06-15 | 2017-05-30 | At&T Intellectual Property I, L.P. | Method and apparatus for providing security using network traffic adjustments |
US9680670B2 (en) | 2014-11-20 | 2017-06-13 | At&T Intellectual Property I, L.P. | Transmission device with channel equalization and control and methods for use therewith |
US9685992B2 (en) | 2014-10-03 | 2017-06-20 | At&T Intellectual Property I, L.P. | Circuit panel network and methods thereof |
US9692101B2 (en) | 2014-08-26 | 2017-06-27 | At&T Intellectual Property I, L.P. | Guided wave couplers for coupling electromagnetic waves between a waveguide surface and a surface of a wire |
US9699785B2 (en) | 2012-12-05 | 2017-07-04 | At&T Intellectual Property I, L.P. | Backhaul link for distributed antenna system |
US9705571B2 (en) | 2015-09-16 | 2017-07-11 | At&T Intellectual Property I, L.P. | Method and apparatus for use with a radio distributed antenna system |
US9705561B2 (en) | 2015-04-24 | 2017-07-11 | At&T Intellectual Property I, L.P. | Directional coupling device and methods for use therewith |
US9722318B2 (en) | 2015-07-14 | 2017-08-01 | At&T Intellectual Property I, L.P. | Method and apparatus for coupling an antenna to a device |
US9729197B2 (en) | 2015-10-01 | 2017-08-08 | At&T Intellectual Property I, L.P. | Method and apparatus for communicating network management traffic over a network |
US9735833B2 (en) | 2015-07-31 | 2017-08-15 | At&T Intellectual Property I, L.P. | Method and apparatus for communications management in a neighborhood network |
US9742462B2 (en) | 2014-12-04 | 2017-08-22 | At&T Intellectual Property I, L.P. | Transmission medium and communication interfaces and methods for use therewith |
US9749053B2 (en) | 2015-07-23 | 2017-08-29 | At&T Intellectual Property I, L.P. | Node device, repeater and methods for use therewith |
US9748626B2 (en) | 2015-05-14 | 2017-08-29 | At&T Intellectual Property I, L.P. | Plurality of cables having different cross-sectional shapes which are bundled together to form a transmission medium |
US9749013B2 (en) | 2015-03-17 | 2017-08-29 | At&T Intellectual Property I, L.P. | Method and apparatus for reducing attenuation of electromagnetic waves guided by a transmission medium |
US9755697B2 (en) | 2014-09-15 | 2017-09-05 | At&T Intellectual Property I, L.P. | Method and apparatus for sensing a condition in a transmission medium of electromagnetic waves |
US9762289B2 (en) | 2014-10-14 | 2017-09-12 | At&T Intellectual Property I, L.P. | Method and apparatus for transmitting or receiving signals in a transportation system |
US9769128B2 (en) | 2015-09-28 | 2017-09-19 | At&T Intellectual Property I, L.P. | Method and apparatus for encryption of communications over a network |
US9769020B2 (en) | 2014-10-21 | 2017-09-19 | At&T Intellectual Property I, L.P. | Method and apparatus for responding to events affecting communications in a communication network |
US9780834B2 (en) | 2014-10-21 | 2017-10-03 | At&T Intellectual Property I, L.P. | Method and apparatus for transmitting electromagnetic waves |
US9793951B2 (en) | 2015-07-15 | 2017-10-17 | At&T Intellectual Property I, L.P. | Method and apparatus for launching a wave mode that mitigates interference |
US9793955B2 (en) | 2015-04-24 | 2017-10-17 | At&T Intellectual Property I, Lp | Passive electrical coupling device and methods for use therewith |
US9793954B2 (en) | 2015-04-28 | 2017-10-17 | At&T Intellectual Property I, L.P. | Magnetic coupling device and methods for use therewith |
US9800327B2 (en) | 2014-11-20 | 2017-10-24 | At&T Intellectual Property I, L.P. | Apparatus for controlling operations of a communication device and methods thereof |
US9820146B2 (en) | 2015-06-12 | 2017-11-14 | At&T Intellectual Property I, L.P. | Method and apparatus for authentication and identity management of communicating devices |
US9836957B2 (en) | 2015-07-14 | 2017-12-05 | At&T Intellectual Property I, L.P. | Method and apparatus for communicating with premises equipment |
US9838896B1 (en) | 2016-12-09 | 2017-12-05 | At&T Intellectual Property I, L.P. | Method and apparatus for assessing network coverage |
US9847850B2 (en) | 2014-10-14 | 2017-12-19 | At&T Intellectual Property I, L.P. | Method and apparatus for adjusting a mode of communication in a communication network |
US9847566B2 (en) | 2015-07-14 | 2017-12-19 | At&T Intellectual Property I, L.P. | Method and apparatus for adjusting a field of a signal to mitigate interference |
US9853342B2 (en) | 2015-07-14 | 2017-12-26 | At&T Intellectual Property I, L.P. | Dielectric transmission medium connector and methods for use therewith |
US9860075B1 (en) | 2016-08-26 | 2018-01-02 | At&T Intellectual Property I, L.P. | Method and communication node for broadband distribution |
US9866309B2 (en) | 2015-06-03 | 2018-01-09 | At&T Intellectual Property I, Lp | Host node device and methods for use therewith |
US9865911B2 (en) | 2015-06-25 | 2018-01-09 | At&T Intellectual Property I, L.P. | Waveguide system for slot radiating first electromagnetic waves that are combined into a non-fundamental wave mode second electromagnetic wave on a transmission medium |
US9871283B2 (en) | 2015-07-23 | 2018-01-16 | At&T Intellectual Property I, Lp | Transmission medium having a dielectric core comprised of plural members connected by a ball and socket configuration |
US9871282B2 (en) | 2015-05-14 | 2018-01-16 | At&T Intellectual Property I, L.P. | At least one transmission medium having a dielectric surface that is covered at least in part by a second dielectric |
US9876570B2 (en) | 2015-02-20 | 2018-01-23 | At&T Intellectual Property I, Lp | Guided-wave transmission device with non-fundamental mode propagation and methods for use therewith |
US9876264B2 (en) | 2015-10-02 | 2018-01-23 | At&T Intellectual Property I, Lp | Communication system, guided wave switch and methods for use therewith |
US9876605B1 (en) | 2016-10-21 | 2018-01-23 | At&T Intellectual Property I, L.P. | Launcher and coupling system to support desired guided wave mode |
US9882257B2 (en) | 2015-07-14 | 2018-01-30 | At&T Intellectual Property I, L.P. | Method and apparatus for launching a wave mode that mitigates interference |
US9882277B2 (en) | 2015-10-02 | 2018-01-30 | At&T Intellectual Property I, Lp | Communication device and antenna assembly with actuated gimbal mount |
US9893795B1 (en) | 2016-12-07 | 2018-02-13 | At&T Intellectual Property I, Lp | Method and repeater for broadband distribution |
US9904535B2 (en) | 2015-09-14 | 2018-02-27 | At&T Intellectual Property I, L.P. | Method and apparatus for distributing software |
US9906269B2 (en) | 2014-09-17 | 2018-02-27 | At&T Intellectual Property I, L.P. | Monitoring and mitigating conditions in a communication network |
US9912381B2 (en) | 2015-06-03 | 2018-03-06 | At&T Intellectual Property I, Lp | Network termination and methods for use therewith |
US9913139B2 (en) | 2015-06-09 | 2018-03-06 | At&T Intellectual Property I, L.P. | Signal fingerprinting for authentication of communicating devices |
US9912027B2 (en) | 2015-07-23 | 2018-03-06 | At&T Intellectual Property I, L.P. | Method and apparatus for exchanging communication signals |
US9912419B1 (en) | 2016-08-24 | 2018-03-06 | At&T Intellectual Property I, L.P. | Method and apparatus for managing a fault in a distributed antenna system |
US9911020B1 (en) | 2016-12-08 | 2018-03-06 | At&T Intellectual Property I, L.P. | Method and apparatus for tracking via a radio frequency identification device |
US9917341B2 (en) | 2015-05-27 | 2018-03-13 | At&T Intellectual Property I, L.P. | Apparatus and method for launching electromagnetic waves and for modifying radial dimensions of the propagating electromagnetic waves |
US9927517B1 (en) | 2016-12-06 | 2018-03-27 | At&T Intellectual Property I, L.P. | Apparatus and methods for sensing rainfall |
US9948354B2 (en) | 2015-04-28 | 2018-04-17 | At&T Intellectual Property I, L.P. | Magnetic coupling device with reflective plate and methods for use therewith |
US9948333B2 (en) | 2015-07-23 | 2018-04-17 | At&T Intellectual Property I, L.P. | Method and apparatus for wireless communications to mitigate interference |
US9954287B2 (en) | 2014-11-20 | 2018-04-24 | At&T Intellectual Property I, L.P. | Apparatus for converting wireless signals and electromagnetic waves and methods thereof |
US9967173B2 (en) | 2015-07-31 | 2018-05-08 | At&T Intellectual Property I, L.P. | Method and apparatus for authentication and identity management of communicating devices |
US9973940B1 (en) | 2017-02-27 | 2018-05-15 | At&T Intellectual Property I, L.P. | Apparatus and methods for dynamic impedance matching of a guided wave launcher |
US9991580B2 (en) | 2016-10-21 | 2018-06-05 | At&T Intellectual Property I, L.P. | Launcher and coupling system for guided wave mode cancellation |
US9998870B1 (en) | 2016-12-08 | 2018-06-12 | At&T Intellectual Property I, L.P. | Method and apparatus for proximity sensing |
US9999038B2 (en) | 2013-05-31 | 2018-06-12 | At&T Intellectual Property I, L.P. | Remote distributed antenna system |
US9997819B2 (en) | 2015-06-09 | 2018-06-12 | At&T Intellectual Property I, L.P. | Transmission medium and method for facilitating propagation of electromagnetic waves via a core |
US10009067B2 (en) | 2014-12-04 | 2018-06-26 | At&T Intellectual Property I, L.P. | Method and apparatus for configuring a communication interface |
US10009065B2 (en) | 2012-12-05 | 2018-06-26 | At&T Intellectual Property I, L.P. | Backhaul link for distributed antenna system |
US10009901B2 (en) | 2015-09-16 | 2018-06-26 | At&T Intellectual Property I, L.P. | Method, apparatus, and computer-readable storage medium for managing utilization of wireless resources between base stations |
US10009063B2 (en) | 2015-09-16 | 2018-06-26 | At&T Intellectual Property I, L.P. | Method and apparatus for use with a radio distributed antenna system having an out-of-band reference signal |
US10020587B2 (en) | 2015-07-31 | 2018-07-10 | At&T Intellectual Property I, L.P. | Radial antenna and methods for use therewith |
US10020844B2 (en) | 2016-12-06 | 2018-07-10 | T&T Intellectual Property I, L.P. | Method and apparatus for broadcast communication via guided waves |
US10027397B2 (en) | 2016-12-07 | 2018-07-17 | At&T Intellectual Property I, L.P. | Distributed antenna system and methods for use therewith |
US10033108B2 (en) | 2015-07-14 | 2018-07-24 | At&T Intellectual Property I, L.P. | Apparatus and methods for generating an electromagnetic wave having a wave mode that mitigates interference |
US10033107B2 (en) | 2015-07-14 | 2018-07-24 | At&T Intellectual Property I, L.P. | Method and apparatus for coupling an antenna to a device |
US10044409B2 (en) | 2015-07-14 | 2018-08-07 | At&T Intellectual Property I, L.P. | Transmission medium and methods for use therewith |
US10051483B2 (en) | 2015-10-16 | 2018-08-14 | At&T Intellectual Property I, L.P. | Method and apparatus for directing wireless signals |
US10051629B2 (en) | 2015-09-16 | 2018-08-14 | At&T Intellectual Property I, L.P. | Method and apparatus for use with a radio distributed antenna system having an in-band reference signal |
US10069535B2 (en) | 2016-12-08 | 2018-09-04 | At&T Intellectual Property I, L.P. | Apparatus and methods for launching electromagnetic waves having a certain electric field structure |
US10074890B2 (en) | 2015-10-02 | 2018-09-11 | At&T Intellectual Property I, L.P. | Communication device and antenna with integrated light assembly |
US10079661B2 (en) | 2015-09-16 | 2018-09-18 | At&T Intellectual Property I, L.P. | Method and apparatus for use with a radio distributed antenna system having a clock reference |
US10090606B2 (en) | 2015-07-15 | 2018-10-02 | At&T Intellectual Property I, L.P. | Antenna system with dielectric array and methods for use therewith |
US10090594B2 (en) | 2016-11-23 | 2018-10-02 | At&T Intellectual Property I, L.P. | Antenna system having structural configurations for assembly |
US10103422B2 (en) | 2016-12-08 | 2018-10-16 | At&T Intellectual Property I, L.P. | Method and apparatus for mounting network devices |
US10103801B2 (en) | 2015-06-03 | 2018-10-16 | At&T Intellectual Property I, L.P. | Host node device and methods for use therewith |
US10135145B2 (en) | 2016-12-06 | 2018-11-20 | At&T Intellectual Property I, L.P. | Apparatus and methods for generating an electromagnetic wave along a transmission medium |
US10135146B2 (en) | 2016-10-18 | 2018-11-20 | At&T Intellectual Property I, L.P. | Apparatus and methods for launching guided waves via circuits |
US10135147B2 (en) | 2016-10-18 | 2018-11-20 | At&T Intellectual Property I, L.P. | Apparatus and methods for launching guided waves via an antenna |
US10136434B2 (en) | 2015-09-16 | 2018-11-20 | At&T Intellectual Property I, L.P. | Method and apparatus for use with a radio distributed antenna system having an ultra-wideband control channel |
US10139820B2 (en) | 2016-12-07 | 2018-11-27 | At&T Intellectual Property I, L.P. | Method and apparatus for deploying equipment of a communication system |
US10142086B2 (en) | 2015-06-11 | 2018-11-27 | At&T Intellectual Property I, L.P. | Repeater and methods for use therewith |
US10144036B2 (en) | 2015-01-30 | 2018-12-04 | At&T Intellectual Property I, L.P. | Method and apparatus for mitigating interference affecting a propagation of electromagnetic waves guided by a transmission medium |
US10148016B2 (en) | 2015-07-14 | 2018-12-04 | At&T Intellectual Property I, L.P. | Apparatus and methods for communicating utilizing an antenna array |
US10154493B2 (en) | 2015-06-03 | 2018-12-11 | At&T Intellectual Property I, L.P. | Network termination and methods for use therewith |
US10170840B2 (en) | 2015-07-14 | 2019-01-01 | At&T Intellectual Property I, L.P. | Apparatus and methods for sending or receiving electromagnetic signals |
US10168695B2 (en) | 2016-12-07 | 2019-01-01 | At&T Intellectual Property I, L.P. | Method and apparatus for controlling an unmanned aircraft |
US10178445B2 (en) | 2016-11-23 | 2019-01-08 | At&T Intellectual Property I, L.P. | Methods, devices, and systems for load balancing between a plurality of waveguides |
US10205655B2 (en) | 2015-07-14 | 2019-02-12 | At&T Intellectual Property I, L.P. | Apparatus and methods for communicating utilizing an antenna array and multiple communication paths |
US10225025B2 (en) | 2016-11-03 | 2019-03-05 | At&T Intellectual Property I, L.P. | Method and apparatus for detecting a fault in a communication system |
US10224634B2 (en) | 2016-11-03 | 2019-03-05 | At&T Intellectual Property I, L.P. | Methods and apparatus for adjusting an operational characteristic of an antenna |
US10243270B2 (en) | 2016-12-07 | 2019-03-26 | At&T Intellectual Property I, L.P. | Beam adaptive multi-feed dielectric antenna system and methods for use therewith |
US10243784B2 (en) | 2014-11-20 | 2019-03-26 | At&T Intellectual Property I, L.P. | System for generating topology information and methods thereof |
US10264586B2 (en) | 2016-12-09 | 2019-04-16 | At&T Mobility Ii Llc | Cloud-based packet controller and methods for use therewith |
US10291334B2 (en) | 2016-11-03 | 2019-05-14 | At&T Intellectual Property I, L.P. | System for detecting a fault in a communication system |
US10291311B2 (en) | 2016-09-09 | 2019-05-14 | At&T Intellectual Property I, L.P. | Method and apparatus for mitigating a fault in a distributed antenna system |
US10298293B2 (en) | 2017-03-13 | 2019-05-21 | At&T Intellectual Property I, L.P. | Apparatus of communication utilizing wireless network devices |
US10305190B2 (en) | 2016-12-01 | 2019-05-28 | At&T Intellectual Property I, L.P. | Reflecting dielectric antenna system and methods for use therewith |
US10312567B2 (en) | 2016-10-26 | 2019-06-04 | At&T Intellectual Property I, L.P. | Launcher with planar strip antenna and methods for use therewith |
US10320586B2 (en) | 2015-07-14 | 2019-06-11 | At&T Intellectual Property I, L.P. | Apparatus and methods for generating non-interfering electromagnetic waves on an insulated transmission medium |
US10326494B2 (en) | 2016-12-06 | 2019-06-18 | At&T Intellectual Property I, L.P. | Apparatus for measurement de-embedding and methods for use therewith |
US10326689B2 (en) | 2016-12-08 | 2019-06-18 | At&T Intellectual Property I, L.P. | Method and system for providing alternative communication paths |
US10341142B2 (en) | 2015-07-14 | 2019-07-02 | At&T Intellectual Property I, L.P. | Apparatus and methods for generating non-interfering electromagnetic waves on an uninsulated conductor |
US10340600B2 (en) | 2016-10-18 | 2019-07-02 | At&T Intellectual Property I, L.P. | Apparatus and methods for launching guided waves via plural waveguide systems |
US10340603B2 (en) | 2016-11-23 | 2019-07-02 | At&T Intellectual Property I, L.P. | Antenna system having shielded structural configurations for assembly |
US10340573B2 (en) | 2016-10-26 | 2019-07-02 | At&T Intellectual Property I, L.P. | Launcher with cylindrical coupling device and methods for use therewith |
US10340601B2 (en) | 2016-11-23 | 2019-07-02 | At&T Intellectual Property I, L.P. | Multi-antenna system and methods for use therewith |
US10340983B2 (en) | 2016-12-09 | 2019-07-02 | At&T Intellectual Property I, L.P. | Method and apparatus for surveying remote sites via guided wave communications |
US10348391B2 (en) | 2015-06-03 | 2019-07-09 | At&T Intellectual Property I, L.P. | Client node device with frequency conversion and methods for use therewith |
US10355367B2 (en) | 2015-10-16 | 2019-07-16 | At&T Intellectual Property I, L.P. | Antenna structure for exchanging wireless signals |
US10359749B2 (en) | 2016-12-07 | 2019-07-23 | At&T Intellectual Property I, L.P. | Method and apparatus for utilities management via guided wave communication |
US10361489B2 (en) | 2016-12-01 | 2019-07-23 | At&T Intellectual Property I, L.P. | Dielectric dish antenna system and methods for use therewith |
US10374316B2 (en) | 2016-10-21 | 2019-08-06 | At&T Intellectual Property I, L.P. | System and dielectric antenna with non-uniform dielectric |
US10382976B2 (en) | 2016-12-06 | 2019-08-13 | At&T Intellectual Property I, L.P. | Method and apparatus for managing wireless communications based on communication paths and network device positions |
US10389037B2 (en) | 2016-12-08 | 2019-08-20 | At&T Intellectual Property I, L.P. | Apparatus and methods for selecting sections of an antenna array and use therewith |
US10389029B2 (en) | 2016-12-07 | 2019-08-20 | At&T Intellectual Property I, L.P. | Multi-feed dielectric antenna system with core selection and methods for use therewith |
US10396887B2 (en) | 2015-06-03 | 2019-08-27 | At&T Intellectual Property I, L.P. | Client node device and methods for use therewith |
US10411356B2 (en) | 2016-12-08 | 2019-09-10 | At&T Intellectual Property I, L.P. | Apparatus and methods for selectively targeting communication devices with an antenna array |
US10439675B2 (en) | 2016-12-06 | 2019-10-08 | At&T Intellectual Property I, L.P. | Method and apparatus for repeating guided wave communication signals |
US10446936B2 (en) | 2016-12-07 | 2019-10-15 | At&T Intellectual Property I, L.P. | Multi-feed dielectric antenna system and methods for use therewith |
US10498044B2 (en) | 2016-11-03 | 2019-12-03 | At&T Intellectual Property I, L.P. | Apparatus for configuring a surface of an antenna |
US10530505B2 (en) | 2016-12-08 | 2020-01-07 | At&T Intellectual Property I, L.P. | Apparatus and methods for launching electromagnetic waves along a transmission medium |
US10535928B2 (en) | 2016-11-23 | 2020-01-14 | At&T Intellectual Property I, L.P. | Antenna system and methods for use therewith |
US10547348B2 (en) | 2016-12-07 | 2020-01-28 | At&T Intellectual Property I, L.P. | Method and apparatus for switching transmission mediums in a communication system |
US10601494B2 (en) | 2016-12-08 | 2020-03-24 | At&T Intellectual Property I, L.P. | Dual-band communication device and method for use therewith |
US10637149B2 (en) | 2016-12-06 | 2020-04-28 | At&T Intellectual Property I, L.P. | Injection molded dielectric antenna and methods for use therewith |
US10650940B2 (en) | 2015-05-15 | 2020-05-12 | At&T Intellectual Property I, L.P. | Transmission medium having a conductive material and methods for use therewith |
US10665942B2 (en) | 2015-10-16 | 2020-05-26 | At&T Intellectual Property I, L.P. | Method and apparatus for adjusting wireless communications |
US10679767B2 (en) | 2015-05-15 | 2020-06-09 | At&T Intellectual Property I, L.P. | Transmission medium having a conductive material and methods for use therewith |
US10694379B2 (en) | 2016-12-06 | 2020-06-23 | At&T Intellectual Property I, L.P. | Waveguide system with device-based authentication and methods for use therewith |
US10727599B2 (en) | 2016-12-06 | 2020-07-28 | At&T Intellectual Property I, L.P. | Launcher with slot antenna and methods for use therewith |
US10755542B2 (en) | 2016-12-06 | 2020-08-25 | At&T Intellectual Property I, L.P. | Method and apparatus for surveillance via guided wave communication |
US10777873B2 (en) | 2016-12-08 | 2020-09-15 | At&T Intellectual Property I, L.P. | Method and apparatus for mounting network devices |
US10784670B2 (en) | 2015-07-23 | 2020-09-22 | At&T Intellectual Property I, L.P. | Antenna support for aligning an antenna |
US10811767B2 (en) | 2016-10-21 | 2020-10-20 | At&T Intellectual Property I, L.P. | System and dielectric antenna with convex dielectric radome |
US10819035B2 (en) | 2016-12-06 | 2020-10-27 | At&T Intellectual Property I, L.P. | Launcher with helical antenna and methods for use therewith |
US10916969B2 (en) | 2016-12-08 | 2021-02-09 | At&T Intellectual Property I, L.P. | Method and apparatus for providing power using an inductive coupling |
US10938108B2 (en) | 2016-12-08 | 2021-03-02 | At&T Intellectual Property I, L.P. | Frequency selective multi-feed dielectric antenna system and methods for use therewith |
US11032819B2 (en) | 2016-09-15 | 2021-06-08 | At&T Intellectual Property I, L.P. | Method and apparatus for use with a radio distributed antenna system having a control channel reference signal |
WO2023131556A1 (en) | 2022-01-10 | 2023-07-13 | Signify Holding B.V. | A time-alignment subsystem and method for use with an optical transceiver |
Families Citing this family (38)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6624916B1 (en) | 1997-02-11 | 2003-09-23 | Quantumbeam Limited | Signalling system |
US6907013B1 (en) * | 1997-12-17 | 2005-06-14 | Infracom, Ltd. | Network communications link |
US6343217B1 (en) * | 1998-11-12 | 2002-01-29 | Legerity, Inc. | Digital cordless telephony with PCM coding |
US6490443B1 (en) | 1999-09-02 | 2002-12-03 | Automated Business Companies | Communication and proximity authorization systems |
US7386238B2 (en) * | 2000-08-15 | 2008-06-10 | Lockheed Martin Corporation | Method and system for infrared data communications |
WO2002015438A1 (en) * | 2000-08-15 | 2002-02-21 | Lockheed Martin Corporation | Infrared data communication system |
DE10048629B4 (en) * | 2000-09-25 | 2004-11-11 | IQ wireless GmbH, Entwicklungsgesellschaft für Systeme und Technologien der Telekommunikation | Point to multipoint communication system with optical signal transmission |
US6922559B2 (en) | 2001-02-26 | 2005-07-26 | Kineto Wireless, Inc. | Unlicensed wireless communications base station to facilitate unlicensed and licensed wireless communications with a subscriber device, and method of operation |
US7308263B2 (en) | 2001-02-26 | 2007-12-11 | Kineto Wireless, Inc. | Apparatus for supporting the handover of a telecommunication session between a licensed wireless system and an unlicensed wireless system |
US20030073431A1 (en) * | 2001-10-16 | 2003-04-17 | Jheroen Dorenbosch | Transferring communications over a network |
FR2832883B1 (en) * | 2001-11-27 | 2006-05-26 | Cit Alcatel | DIGITAL SIGNAL TRANSMISSION SYSTEM FOR A SPA VEHICLE |
IT1403065B1 (en) * | 2010-12-01 | 2013-10-04 | Andrew Wireless Systems Gmbh | DISTRIBUTED ANTENNA SYSTEM FOR MIMO SIGNALS. |
US7200567B2 (en) * | 2002-01-04 | 2007-04-03 | Lockheed Martin Corporation | Purchasing aid logistics appliance and method for use |
US7672274B2 (en) * | 2002-01-11 | 2010-03-02 | Broadcom Corporation | Mobility support via routing |
US6848657B2 (en) | 2002-01-17 | 2005-02-01 | The Creative Train Company, Llc | Dynamic self-teaching train track layout learning and control system |
US7787572B2 (en) | 2005-04-07 | 2010-08-31 | Rambus Inc. | Advanced signal processors for interference cancellation in baseband receivers |
EP2334136A3 (en) * | 2002-10-18 | 2012-07-18 | Kineto Wireless, Inc. | Method and apparatuses for channel activation for a telecommunication device |
US7565145B2 (en) * | 2002-10-18 | 2009-07-21 | Kineto Wireless, Inc. | Handover messaging in an unlicensed mobile access telecommunications system |
US7471655B2 (en) | 2003-10-17 | 2008-12-30 | Kineto Wireless, Inc. | Channel activation messaging in an unlicensed mobile access telecommunications system |
US7953423B2 (en) | 2002-10-18 | 2011-05-31 | Kineto Wireless, Inc. | Messaging in an unlicensed mobile access telecommunications system |
US7349698B2 (en) | 2002-10-18 | 2008-03-25 | Kineto Wireless, Inc. | Registration messaging in an unlicensed mobile access telecommunications system |
US7606190B2 (en) | 2002-10-18 | 2009-10-20 | Kineto Wireless, Inc. | Apparatus and messages for interworking between unlicensed access network and GPRS network for data services |
US7009501B2 (en) * | 2003-05-22 | 2006-03-07 | Disney Enterprises, Inc. | System and method of optical data communication with multiple simultaneous emitters and receivers |
US7957348B1 (en) | 2004-04-21 | 2011-06-07 | Kineto Wireless, Inc. | Method and system for signaling traffic and media types within a communications network switching system |
US7940746B2 (en) | 2004-08-24 | 2011-05-10 | Comcast Cable Holdings, Llc | Method and system for locating a voice over internet protocol (VoIP) device connected to a network |
US7933598B1 (en) | 2005-03-14 | 2011-04-26 | Kineto Wireless, Inc. | Methods and apparatuses for effecting handover in integrated wireless systems |
US7567828B1 (en) * | 2005-07-01 | 2009-07-28 | Plantronics, Inc. | Look and tune mobile communication device |
US20080039086A1 (en) | 2006-07-14 | 2008-02-14 | Gallagher Michael D | Generic Access to the Iu Interface |
US20090265543A1 (en) | 2008-04-18 | 2009-10-22 | Amit Khetawat | Home Node B System Architecture with Support for RANAP User Adaptation Protocol |
US8208414B2 (en) * | 2008-06-24 | 2012-06-26 | Lgc Wireless, Inc. | System and method for configurable time-division duplex interface |
US8310963B2 (en) * | 2008-06-24 | 2012-11-13 | Adc Telecommunications, Inc. | System and method for synchronized time-division duplex signal switching |
US7961689B2 (en) * | 2008-08-18 | 2011-06-14 | Adc Telecommunications, Inc. | Method and apparatus for determining an end of a subframe in a TDD system |
IT1398025B1 (en) | 2010-02-12 | 2013-02-07 | Andrew Llc | DISTRIBUTED ANTENNA SYSTEM FOR MIMO COMMUNICATIONS. |
CN101964768B (en) * | 2010-08-20 | 2013-10-02 | 苏州本控电子科技有限公司 | Adaptive infrared anti-jamming transmission method |
WO2012044969A1 (en) | 2010-10-01 | 2012-04-05 | Andrew Llc | Distributed antenna system for mimo signals |
US8693342B2 (en) | 2011-10-28 | 2014-04-08 | Adc Telecommunications, Inc. | Distributed antenna system using time division duplexing scheme |
JP6766967B2 (en) * | 2016-12-27 | 2020-10-14 | 株式会社デンソー | Systems and methods for microlocation sensor communication |
JP6618657B2 (en) * | 2017-05-23 | 2019-12-11 | 三菱電機株式会社 | Base station apparatus, ground station apparatus, and ground antenna apparatus |
Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4456793A (en) * | 1982-06-09 | 1984-06-26 | Bell Telephone Laboratories, Incorporated | Cordless telephone system |
US5201061A (en) * | 1990-07-23 | 1993-04-06 | Motorola, Inc. | Method and apparatus for synchronizing simulcast systems |
US5361398A (en) * | 1993-01-29 | 1994-11-01 | Motorola, Inc. | Method and apparatus for transmission path delay measurements using adaptive demodulation |
US5566022A (en) * | 1993-06-11 | 1996-10-15 | Segev; Uri | Infra-red communication system |
Family Cites Families (31)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4553267A (en) * | 1981-07-31 | 1985-11-12 | Crimmins James W | Infrared telephone extension modulation system |
US4757553A (en) * | 1984-05-15 | 1988-07-12 | Crimmins James W | Communication system with portable unit |
US4727600A (en) * | 1985-02-15 | 1988-02-23 | Emik Avakian | Infrared data communication system |
US5103108A (en) * | 1985-10-17 | 1992-04-07 | Crimmins James W | Distributed infrared communication system |
US4977619A (en) * | 1986-10-01 | 1990-12-11 | Crimmins James W | Distributed infrared communication system |
US5142396A (en) * | 1987-03-23 | 1992-08-25 | Johnson Service Company | Diffused infrared communication control system |
US5247380A (en) * | 1988-01-27 | 1993-09-21 | Spectrix Corp | Infrared communications network |
US4975926A (en) * | 1989-03-30 | 1990-12-04 | Guenther Knapp | Wireless indoor data communication system |
US5477541A (en) * | 1989-09-29 | 1995-12-19 | White; Richard E. | Addressing technique for storing and referencing packet data |
GB2249918A (en) * | 1990-11-14 | 1992-05-20 | Philips Electronic Associated | Channel scanning in tdd cordless telephone system |
CA2054591C (en) * | 1991-02-28 | 1996-09-03 | Giovanni Vannucci | Wireless telecommunication systems |
US5214526A (en) * | 1991-06-04 | 1993-05-25 | Apple Computer, Inc. | Pulse modulated infrared data communications link |
US5463623A (en) * | 1991-07-31 | 1995-10-31 | At&T Ipm Corp. | Integrated wireless telecommunication and local area network system |
US5475381A (en) * | 1992-01-28 | 1995-12-12 | Servio Logic Corp. | High speed infrared communications system using pulse sets |
GB2265521A (en) * | 1992-03-28 | 1993-09-29 | Motorola Ltd | Communications system with extended channels |
US5416778A (en) * | 1992-06-26 | 1995-05-16 | U.S. Philips Corporation | Digital radio communication system and primary and secondary station for use in such a system |
US5371623A (en) * | 1992-07-01 | 1994-12-06 | Motorola, Inc. | High bit rate infrared communication system for overcoming multipath |
US5394410A (en) * | 1992-10-30 | 1995-02-28 | International Business Machines Corporation | Differentially coded and guard pulse position modulation for communication networks |
GB2272610B (en) * | 1992-11-12 | 1996-10-09 | Northern Telecom Ltd | Telecommunications systems |
US5440613A (en) * | 1992-12-30 | 1995-08-08 | At&T Corp. | Architecture for a cellular wireless telecommunication system |
US5548806A (en) * | 1993-01-25 | 1996-08-20 | Kokusai Denshin Denwa Co., Ltd. | Mobile communication system having a cell structure constituted by integrating macro cells and micro cells |
US5351149A (en) * | 1993-03-25 | 1994-09-27 | K And M Electronics, Inc. | ASK optical transmitter |
US5319191A (en) * | 1993-03-25 | 1994-06-07 | K & M Electronics, Inc. | Ask receiver with signal delay and stretching |
US5383043A (en) * | 1993-03-26 | 1995-01-17 | Su; Chih-Hai | Omni-directional infrared sensing circuit |
US5463673A (en) * | 1993-04-29 | 1995-10-31 | Northern Telecom Limited | In-building radio deployment technique for wireless personal communications systems |
DE4317895C2 (en) * | 1993-05-28 | 1996-11-14 | Siemens Ag | Method for synchronizing base stations in a multi-cellular, wireless telephone system |
US5440559A (en) * | 1993-11-10 | 1995-08-08 | Seiko Communications Holding N.V. | Portable wireless communication device |
US5479408A (en) * | 1994-02-22 | 1995-12-26 | Will; Craig A. | Wireless personal paging, communications, and locating system |
US5677909A (en) * | 1994-05-11 | 1997-10-14 | Spectrix Corporation | Apparatus for exchanging data between a central station and a plurality of wireless remote stations on a time divided commnication channel |
US5463617A (en) * | 1994-09-30 | 1995-10-31 | Grube; Gary W. | Method for providing caller interrupt in a time division multiplexed wireless communication system |
US5475677A (en) * | 1994-12-29 | 1995-12-12 | Bell Communications Research Inc. | Compatible licensed and unlicensed band portable handset unit for TDMA wireless communications system |
-
1996
- 1996-03-22 US US08/624,852 patent/US5867292A/en not_active Expired - Fee Related
-
1997
- 1997-03-19 WO PCT/US1997/004318 patent/WO1997035387A1/en not_active Application Discontinuation
- 1997-03-19 EP EP97916058A patent/EP0894374A1/en not_active Withdrawn
- 1997-03-19 AU AU23326/97A patent/AU714753B2/en not_active Ceased
- 1997-03-19 CA CA002249450A patent/CA2249450C/en not_active Expired - Fee Related
- 1997-03-19 CN CN97194748A patent/CN1220789A/en active Pending
- 1997-03-19 IL IL12628897A patent/IL126288A0/en unknown
- 1997-03-19 JP JP9533627A patent/JP2000507058A/en active Pending
-
1998
- 1998-02-17 US US09/025,062 patent/US5969842A/en not_active Expired - Fee Related
- 1998-02-17 US US09/024,995 patent/US6426819B1/en not_active Expired - Fee Related
Patent Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4456793A (en) * | 1982-06-09 | 1984-06-26 | Bell Telephone Laboratories, Incorporated | Cordless telephone system |
US5201061A (en) * | 1990-07-23 | 1993-04-06 | Motorola, Inc. | Method and apparatus for synchronizing simulcast systems |
US5361398A (en) * | 1993-01-29 | 1994-11-01 | Motorola, Inc. | Method and apparatus for transmission path delay measurements using adaptive demodulation |
US5566022A (en) * | 1993-06-11 | 1996-10-15 | Segev; Uri | Infra-red communication system |
Cited By (220)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0952689A2 (en) * | 1998-04-22 | 1999-10-27 | Sony Corporation | Transmitter, receiver and distribution medium for an infrared communication system |
EP0952689A3 (en) * | 1998-04-22 | 2004-01-07 | Sony Corporation | Transmitter, receiver and distribution medium for an infrared communication system |
US10009065B2 (en) | 2012-12-05 | 2018-06-26 | At&T Intellectual Property I, L.P. | Backhaul link for distributed antenna system |
US10194437B2 (en) | 2012-12-05 | 2019-01-29 | At&T Intellectual Property I, L.P. | Backhaul link for distributed antenna system |
US9788326B2 (en) | 2012-12-05 | 2017-10-10 | At&T Intellectual Property I, L.P. | Backhaul link for distributed antenna system |
US9699785B2 (en) | 2012-12-05 | 2017-07-04 | At&T Intellectual Property I, L.P. | Backhaul link for distributed antenna system |
US10051630B2 (en) | 2013-05-31 | 2018-08-14 | At&T Intellectual Property I, L.P. | Remote distributed antenna system |
US9525524B2 (en) | 2013-05-31 | 2016-12-20 | At&T Intellectual Property I, L.P. | Remote distributed antenna system |
US9930668B2 (en) | 2013-05-31 | 2018-03-27 | At&T Intellectual Property I, L.P. | Remote distributed antenna system |
US10091787B2 (en) | 2013-05-31 | 2018-10-02 | At&T Intellectual Property I, L.P. | Remote distributed antenna system |
US9999038B2 (en) | 2013-05-31 | 2018-06-12 | At&T Intellectual Property I, L.P. | Remote distributed antenna system |
US9154966B2 (en) | 2013-11-06 | 2015-10-06 | At&T Intellectual Property I, Lp | Surface-wave communications and methods thereof |
US9674711B2 (en) | 2013-11-06 | 2017-06-06 | At&T Intellectual Property I, L.P. | Surface-wave communications and methods thereof |
US9467870B2 (en) | 2013-11-06 | 2016-10-11 | At&T Intellectual Property I, L.P. | Surface-wave communications and methods thereof |
US9661505B2 (en) | 2013-11-06 | 2017-05-23 | At&T Intellectual Property I, L.P. | Surface-wave communications and methods thereof |
US9876584B2 (en) | 2013-12-10 | 2018-01-23 | At&T Intellectual Property I, L.P. | Quasi-optical coupler |
US9209902B2 (en) | 2013-12-10 | 2015-12-08 | At&T Intellectual Property I, L.P. | Quasi-optical coupler |
US9479266B2 (en) | 2013-12-10 | 2016-10-25 | At&T Intellectual Property I, L.P. | Quasi-optical coupler |
US9794003B2 (en) | 2013-12-10 | 2017-10-17 | At&T Intellectual Property I, L.P. | Quasi-optical coupler |
US9692101B2 (en) | 2014-08-26 | 2017-06-27 | At&T Intellectual Property I, L.P. | Guided wave couplers for coupling electromagnetic waves between a waveguide surface and a surface of a wire |
US10096881B2 (en) | 2014-08-26 | 2018-10-09 | At&T Intellectual Property I, L.P. | Guided wave couplers for coupling electromagnetic waves to an outer surface of a transmission medium |
US9755697B2 (en) | 2014-09-15 | 2017-09-05 | At&T Intellectual Property I, L.P. | Method and apparatus for sensing a condition in a transmission medium of electromagnetic waves |
US9768833B2 (en) | 2014-09-15 | 2017-09-19 | At&T Intellectual Property I, L.P. | Method and apparatus for sensing a condition in a transmission medium of electromagnetic waves |
US10063280B2 (en) | 2014-09-17 | 2018-08-28 | At&T Intellectual Property I, L.P. | Monitoring and mitigating conditions in a communication network |
US9906269B2 (en) | 2014-09-17 | 2018-02-27 | At&T Intellectual Property I, L.P. | Monitoring and mitigating conditions in a communication network |
US9628854B2 (en) | 2014-09-29 | 2017-04-18 | At&T Intellectual Property I, L.P. | Method and apparatus for distributing content in a communication network |
US9973416B2 (en) | 2014-10-02 | 2018-05-15 | At&T Intellectual Property I, L.P. | Method and apparatus that provides fault tolerance in a communication network |
US9615269B2 (en) | 2014-10-02 | 2017-04-04 | At&T Intellectual Property I, L.P. | Method and apparatus that provides fault tolerance in a communication network |
US9998932B2 (en) | 2014-10-02 | 2018-06-12 | At&T Intellectual Property I, L.P. | Method and apparatus that provides fault tolerance in a communication network |
US9685992B2 (en) | 2014-10-03 | 2017-06-20 | At&T Intellectual Property I, L.P. | Circuit panel network and methods thereof |
US9866276B2 (en) | 2014-10-10 | 2018-01-09 | At&T Intellectual Property I, L.P. | Method and apparatus for arranging communication sessions in a communication system |
US9503189B2 (en) | 2014-10-10 | 2016-11-22 | At&T Intellectual Property I, L.P. | Method and apparatus for arranging communication sessions in a communication system |
US9847850B2 (en) | 2014-10-14 | 2017-12-19 | At&T Intellectual Property I, L.P. | Method and apparatus for adjusting a mode of communication in a communication network |
US9762289B2 (en) | 2014-10-14 | 2017-09-12 | At&T Intellectual Property I, L.P. | Method and apparatus for transmitting or receiving signals in a transportation system |
US9973299B2 (en) | 2014-10-14 | 2018-05-15 | At&T Intellectual Property I, L.P. | Method and apparatus for adjusting a mode of communication in a communication network |
US9960808B2 (en) | 2014-10-21 | 2018-05-01 | At&T Intellectual Property I, L.P. | Guided-wave transmission device and methods for use therewith |
US9596001B2 (en) | 2014-10-21 | 2017-03-14 | At&T Intellectual Property I, L.P. | Apparatus for providing communication services and methods thereof |
US9705610B2 (en) | 2014-10-21 | 2017-07-11 | At&T Intellectual Property I, L.P. | Transmission device with impairment compensation and methods for use therewith |
US9954286B2 (en) | 2014-10-21 | 2018-04-24 | At&T Intellectual Property I, L.P. | Guided-wave transmission device with non-fundamental mode propagation and methods for use therewith |
US9948355B2 (en) | 2014-10-21 | 2018-04-17 | At&T Intellectual Property I, L.P. | Apparatus for providing communication services and methods thereof |
US9571209B2 (en) | 2014-10-21 | 2017-02-14 | At&T Intellectual Property I, L.P. | Transmission device with impairment compensation and methods for use therewith |
US9577307B2 (en) | 2014-10-21 | 2017-02-21 | At&T Intellectual Property I, L.P. | Guided-wave transmission device and methods for use therewith |
US9564947B2 (en) | 2014-10-21 | 2017-02-07 | At&T Intellectual Property I, L.P. | Guided-wave transmission device with diversity and methods for use therewith |
US9912033B2 (en) | 2014-10-21 | 2018-03-06 | At&T Intellectual Property I, Lp | Guided wave coupler, coupling module and methods for use therewith |
US9577306B2 (en) | 2014-10-21 | 2017-02-21 | At&T Intellectual Property I, L.P. | Guided-wave transmission device and methods for use therewith |
US9525210B2 (en) | 2014-10-21 | 2016-12-20 | At&T Intellectual Property I, L.P. | Guided-wave transmission device with non-fundamental mode propagation and methods for use therewith |
US9876587B2 (en) | 2014-10-21 | 2018-01-23 | At&T Intellectual Property I, L.P. | Transmission device with impairment compensation and methods for use therewith |
US9520945B2 (en) | 2014-10-21 | 2016-12-13 | At&T Intellectual Property I, L.P. | Apparatus for providing communication services and methods thereof |
US9871558B2 (en) | 2014-10-21 | 2018-01-16 | At&T Intellectual Property I, L.P. | Guided-wave transmission device and methods for use therewith |
US9312919B1 (en) | 2014-10-21 | 2016-04-12 | At&T Intellectual Property I, Lp | Transmission device with impairment compensation and methods for use therewith |
US9627768B2 (en) | 2014-10-21 | 2017-04-18 | At&T Intellectual Property I, L.P. | Guided-wave transmission device with non-fundamental mode propagation and methods for use therewith |
US9653770B2 (en) | 2014-10-21 | 2017-05-16 | At&T Intellectual Property I, L.P. | Guided wave coupler, coupling module and methods for use therewith |
US9780834B2 (en) | 2014-10-21 | 2017-10-03 | At&T Intellectual Property I, L.P. | Method and apparatus for transmitting electromagnetic waves |
US9769020B2 (en) | 2014-10-21 | 2017-09-19 | At&T Intellectual Property I, L.P. | Method and apparatus for responding to events affecting communications in a communication network |
US9742521B2 (en) | 2014-11-20 | 2017-08-22 | At&T Intellectual Property I, L.P. | Transmission device with mode division multiplexing and methods for use therewith |
US9954287B2 (en) | 2014-11-20 | 2018-04-24 | At&T Intellectual Property I, L.P. | Apparatus for converting wireless signals and electromagnetic waves and methods thereof |
US9712350B2 (en) | 2014-11-20 | 2017-07-18 | At&T Intellectual Property I, L.P. | Transmission device with channel equalization and control and methods for use therewith |
US9544006B2 (en) | 2014-11-20 | 2017-01-10 | At&T Intellectual Property I, L.P. | Transmission device with mode division multiplexing and methods for use therewith |
US10243784B2 (en) | 2014-11-20 | 2019-03-26 | At&T Intellectual Property I, L.P. | System for generating topology information and methods thereof |
US9531427B2 (en) | 2014-11-20 | 2016-12-27 | At&T Intellectual Property I, L.P. | Transmission device with mode division multiplexing and methods for use therewith |
US9800327B2 (en) | 2014-11-20 | 2017-10-24 | At&T Intellectual Property I, L.P. | Apparatus for controlling operations of a communication device and methods thereof |
US9680670B2 (en) | 2014-11-20 | 2017-06-13 | At&T Intellectual Property I, L.P. | Transmission device with channel equalization and control and methods for use therewith |
US9654173B2 (en) | 2014-11-20 | 2017-05-16 | At&T Intellectual Property I, L.P. | Apparatus for powering a communication device and methods thereof |
US9749083B2 (en) | 2014-11-20 | 2017-08-29 | At&T Intellectual Property I, L.P. | Transmission device with mode division multiplexing and methods for use therewith |
US10009067B2 (en) | 2014-12-04 | 2018-06-26 | At&T Intellectual Property I, L.P. | Method and apparatus for configuring a communication interface |
US9742462B2 (en) | 2014-12-04 | 2017-08-22 | At&T Intellectual Property I, L.P. | Transmission medium and communication interfaces and methods for use therewith |
US10144036B2 (en) | 2015-01-30 | 2018-12-04 | At&T Intellectual Property I, L.P. | Method and apparatus for mitigating interference affecting a propagation of electromagnetic waves guided by a transmission medium |
US9876571B2 (en) | 2015-02-20 | 2018-01-23 | At&T Intellectual Property I, Lp | Guided-wave transmission device with non-fundamental mode propagation and methods for use therewith |
US9876570B2 (en) | 2015-02-20 | 2018-01-23 | At&T Intellectual Property I, Lp | Guided-wave transmission device with non-fundamental mode propagation and methods for use therewith |
US9749013B2 (en) | 2015-03-17 | 2017-08-29 | At&T Intellectual Property I, L.P. | Method and apparatus for reducing attenuation of electromagnetic waves guided by a transmission medium |
US9705561B2 (en) | 2015-04-24 | 2017-07-11 | At&T Intellectual Property I, L.P. | Directional coupling device and methods for use therewith |
US9793955B2 (en) | 2015-04-24 | 2017-10-17 | At&T Intellectual Property I, Lp | Passive electrical coupling device and methods for use therewith |
US10224981B2 (en) | 2015-04-24 | 2019-03-05 | At&T Intellectual Property I, Lp | Passive electrical coupling device and methods for use therewith |
US9831912B2 (en) | 2015-04-24 | 2017-11-28 | At&T Intellectual Property I, Lp | Directional coupling device and methods for use therewith |
US9948354B2 (en) | 2015-04-28 | 2018-04-17 | At&T Intellectual Property I, L.P. | Magnetic coupling device with reflective plate and methods for use therewith |
US9793954B2 (en) | 2015-04-28 | 2017-10-17 | At&T Intellectual Property I, L.P. | Magnetic coupling device and methods for use therewith |
US9887447B2 (en) | 2015-05-14 | 2018-02-06 | At&T Intellectual Property I, L.P. | Transmission medium having multiple cores and methods for use therewith |
US9490869B1 (en) | 2015-05-14 | 2016-11-08 | At&T Intellectual Property I, L.P. | Transmission medium having multiple cores and methods for use therewith |
US9871282B2 (en) | 2015-05-14 | 2018-01-16 | At&T Intellectual Property I, L.P. | At least one transmission medium having a dielectric surface that is covered at least in part by a second dielectric |
US9748626B2 (en) | 2015-05-14 | 2017-08-29 | At&T Intellectual Property I, L.P. | Plurality of cables having different cross-sectional shapes which are bundled together to form a transmission medium |
US10679767B2 (en) | 2015-05-15 | 2020-06-09 | At&T Intellectual Property I, L.P. | Transmission medium having a conductive material and methods for use therewith |
US10650940B2 (en) | 2015-05-15 | 2020-05-12 | At&T Intellectual Property I, L.P. | Transmission medium having a conductive material and methods for use therewith |
US9917341B2 (en) | 2015-05-27 | 2018-03-13 | At&T Intellectual Property I, L.P. | Apparatus and method for launching electromagnetic waves and for modifying radial dimensions of the propagating electromagnetic waves |
US9912382B2 (en) | 2015-06-03 | 2018-03-06 | At&T Intellectual Property I, Lp | Network termination and methods for use therewith |
US10797781B2 (en) | 2015-06-03 | 2020-10-06 | At&T Intellectual Property I, L.P. | Client node device and methods for use therewith |
US10812174B2 (en) | 2015-06-03 | 2020-10-20 | At&T Intellectual Property I, L.P. | Client node device and methods for use therewith |
US10050697B2 (en) | 2015-06-03 | 2018-08-14 | At&T Intellectual Property I, L.P. | Host node device and methods for use therewith |
US10348391B2 (en) | 2015-06-03 | 2019-07-09 | At&T Intellectual Property I, L.P. | Client node device with frequency conversion and methods for use therewith |
US10154493B2 (en) | 2015-06-03 | 2018-12-11 | At&T Intellectual Property I, L.P. | Network termination and methods for use therewith |
US9967002B2 (en) | 2015-06-03 | 2018-05-08 | At&T Intellectual I, Lp | Network termination and methods for use therewith |
US9866309B2 (en) | 2015-06-03 | 2018-01-09 | At&T Intellectual Property I, Lp | Host node device and methods for use therewith |
US9935703B2 (en) | 2015-06-03 | 2018-04-03 | At&T Intellectual Property I, L.P. | Host node device and methods for use therewith |
US9912381B2 (en) | 2015-06-03 | 2018-03-06 | At&T Intellectual Property I, Lp | Network termination and methods for use therewith |
US10396887B2 (en) | 2015-06-03 | 2019-08-27 | At&T Intellectual Property I, L.P. | Client node device and methods for use therewith |
US10103801B2 (en) | 2015-06-03 | 2018-10-16 | At&T Intellectual Property I, L.P. | Host node device and methods for use therewith |
US9997819B2 (en) | 2015-06-09 | 2018-06-12 | At&T Intellectual Property I, L.P. | Transmission medium and method for facilitating propagation of electromagnetic waves via a core |
US9913139B2 (en) | 2015-06-09 | 2018-03-06 | At&T Intellectual Property I, L.P. | Signal fingerprinting for authentication of communicating devices |
US10142010B2 (en) | 2015-06-11 | 2018-11-27 | At&T Intellectual Property I, L.P. | Repeater and methods for use therewith |
US10027398B2 (en) | 2015-06-11 | 2018-07-17 | At&T Intellectual Property I, Lp | Repeater and methods for use therewith |
US10142086B2 (en) | 2015-06-11 | 2018-11-27 | At&T Intellectual Property I, L.P. | Repeater and methods for use therewith |
US9608692B2 (en) | 2015-06-11 | 2017-03-28 | At&T Intellectual Property I, L.P. | Repeater and methods for use therewith |
US9820146B2 (en) | 2015-06-12 | 2017-11-14 | At&T Intellectual Property I, L.P. | Method and apparatus for authentication and identity management of communicating devices |
US9667317B2 (en) | 2015-06-15 | 2017-05-30 | At&T Intellectual Property I, L.P. | Method and apparatus for providing security using network traffic adjustments |
US10069185B2 (en) | 2015-06-25 | 2018-09-04 | At&T Intellectual Property I, L.P. | Methods and apparatus for inducing a non-fundamental wave mode on a transmission medium |
US9640850B2 (en) | 2015-06-25 | 2017-05-02 | At&T Intellectual Property I, L.P. | Methods and apparatus for inducing a non-fundamental wave mode on a transmission medium |
US10090601B2 (en) | 2015-06-25 | 2018-10-02 | At&T Intellectual Property I, L.P. | Waveguide system and methods for inducing a non-fundamental wave mode on a transmission medium |
US9787412B2 (en) | 2015-06-25 | 2017-10-10 | At&T Intellectual Property I, L.P. | Methods and apparatus for inducing a fundamental wave mode on a transmission medium |
US9509415B1 (en) | 2015-06-25 | 2016-11-29 | At&T Intellectual Property I, L.P. | Methods and apparatus for inducing a fundamental wave mode on a transmission medium |
US9865911B2 (en) | 2015-06-25 | 2018-01-09 | At&T Intellectual Property I, L.P. | Waveguide system for slot radiating first electromagnetic waves that are combined into a non-fundamental wave mode second electromagnetic wave on a transmission medium |
US9882657B2 (en) | 2015-06-25 | 2018-01-30 | At&T Intellectual Property I, L.P. | Methods and apparatus for inducing a fundamental wave mode on a transmission medium |
US10033108B2 (en) | 2015-07-14 | 2018-07-24 | At&T Intellectual Property I, L.P. | Apparatus and methods for generating an electromagnetic wave having a wave mode that mitigates interference |
US9722318B2 (en) | 2015-07-14 | 2017-08-01 | At&T Intellectual Property I, L.P. | Method and apparatus for coupling an antenna to a device |
US10044409B2 (en) | 2015-07-14 | 2018-08-07 | At&T Intellectual Property I, L.P. | Transmission medium and methods for use therewith |
US10320586B2 (en) | 2015-07-14 | 2019-06-11 | At&T Intellectual Property I, L.P. | Apparatus and methods for generating non-interfering electromagnetic waves on an insulated transmission medium |
US9947982B2 (en) | 2015-07-14 | 2018-04-17 | At&T Intellectual Property I, Lp | Dielectric transmission medium connector and methods for use therewith |
US9929755B2 (en) | 2015-07-14 | 2018-03-27 | At&T Intellectual Property I, L.P. | Method and apparatus for coupling an antenna to a device |
US10341142B2 (en) | 2015-07-14 | 2019-07-02 | At&T Intellectual Property I, L.P. | Apparatus and methods for generating non-interfering electromagnetic waves on an uninsulated conductor |
US10205655B2 (en) | 2015-07-14 | 2019-02-12 | At&T Intellectual Property I, L.P. | Apparatus and methods for communicating utilizing an antenna array and multiple communication paths |
US10170840B2 (en) | 2015-07-14 | 2019-01-01 | At&T Intellectual Property I, L.P. | Apparatus and methods for sending or receiving electromagnetic signals |
US10033107B2 (en) | 2015-07-14 | 2018-07-24 | At&T Intellectual Property I, L.P. | Method and apparatus for coupling an antenna to a device |
US9836957B2 (en) | 2015-07-14 | 2017-12-05 | At&T Intellectual Property I, L.P. | Method and apparatus for communicating with premises equipment |
US10148016B2 (en) | 2015-07-14 | 2018-12-04 | At&T Intellectual Property I, L.P. | Apparatus and methods for communicating utilizing an antenna array |
US9628116B2 (en) | 2015-07-14 | 2017-04-18 | At&T Intellectual Property I, L.P. | Apparatus and methods for transmitting wireless signals |
US9847566B2 (en) | 2015-07-14 | 2017-12-19 | At&T Intellectual Property I, L.P. | Method and apparatus for adjusting a field of a signal to mitigate interference |
US9853342B2 (en) | 2015-07-14 | 2017-12-26 | At&T Intellectual Property I, L.P. | Dielectric transmission medium connector and methods for use therewith |
US9882257B2 (en) | 2015-07-14 | 2018-01-30 | At&T Intellectual Property I, L.P. | Method and apparatus for launching a wave mode that mitigates interference |
US10090606B2 (en) | 2015-07-15 | 2018-10-02 | At&T Intellectual Property I, L.P. | Antenna system with dielectric array and methods for use therewith |
US9608740B2 (en) | 2015-07-15 | 2017-03-28 | At&T Intellectual Property I, L.P. | Method and apparatus for launching a wave mode that mitigates interference |
US9793951B2 (en) | 2015-07-15 | 2017-10-17 | At&T Intellectual Property I, L.P. | Method and apparatus for launching a wave mode that mitigates interference |
US10074886B2 (en) | 2015-07-23 | 2018-09-11 | At&T Intellectual Property I, L.P. | Dielectric transmission medium comprising a plurality of rigid dielectric members coupled together in a ball and socket configuration |
US9871283B2 (en) | 2015-07-23 | 2018-01-16 | At&T Intellectual Property I, Lp | Transmission medium having a dielectric core comprised of plural members connected by a ball and socket configuration |
US9806818B2 (en) | 2015-07-23 | 2017-10-31 | At&T Intellectual Property I, Lp | Node device, repeater and methods for use therewith |
US9948333B2 (en) | 2015-07-23 | 2018-04-17 | At&T Intellectual Property I, L.P. | Method and apparatus for wireless communications to mitigate interference |
US9912027B2 (en) | 2015-07-23 | 2018-03-06 | At&T Intellectual Property I, L.P. | Method and apparatus for exchanging communication signals |
US9749053B2 (en) | 2015-07-23 | 2017-08-29 | At&T Intellectual Property I, L.P. | Node device, repeater and methods for use therewith |
US10784670B2 (en) | 2015-07-23 | 2020-09-22 | At&T Intellectual Property I, L.P. | Antenna support for aligning an antenna |
US9461706B1 (en) | 2015-07-31 | 2016-10-04 | At&T Intellectual Property I, Lp | Method and apparatus for exchanging communication signals |
US10020587B2 (en) | 2015-07-31 | 2018-07-10 | At&T Intellectual Property I, L.P. | Radial antenna and methods for use therewith |
US9735833B2 (en) | 2015-07-31 | 2017-08-15 | At&T Intellectual Property I, L.P. | Method and apparatus for communications management in a neighborhood network |
US9838078B2 (en) | 2015-07-31 | 2017-12-05 | At&T Intellectual Property I, L.P. | Method and apparatus for exchanging communication signals |
US9967173B2 (en) | 2015-07-31 | 2018-05-08 | At&T Intellectual Property I, L.P. | Method and apparatus for authentication and identity management of communicating devices |
US9904535B2 (en) | 2015-09-14 | 2018-02-27 | At&T Intellectual Property I, L.P. | Method and apparatus for distributing software |
US10009063B2 (en) | 2015-09-16 | 2018-06-26 | At&T Intellectual Property I, L.P. | Method and apparatus for use with a radio distributed antenna system having an out-of-band reference signal |
US10079661B2 (en) | 2015-09-16 | 2018-09-18 | At&T Intellectual Property I, L.P. | Method and apparatus for use with a radio distributed antenna system having a clock reference |
US9705571B2 (en) | 2015-09-16 | 2017-07-11 | At&T Intellectual Property I, L.P. | Method and apparatus for use with a radio distributed antenna system |
US10051629B2 (en) | 2015-09-16 | 2018-08-14 | At&T Intellectual Property I, L.P. | Method and apparatus for use with a radio distributed antenna system having an in-band reference signal |
US10225842B2 (en) | 2015-09-16 | 2019-03-05 | At&T Intellectual Property I, L.P. | Method, device and storage medium for communications using a modulated signal and a reference signal |
US10136434B2 (en) | 2015-09-16 | 2018-11-20 | At&T Intellectual Property I, L.P. | Method and apparatus for use with a radio distributed antenna system having an ultra-wideband control channel |
US10009901B2 (en) | 2015-09-16 | 2018-06-26 | At&T Intellectual Property I, L.P. | Method, apparatus, and computer-readable storage medium for managing utilization of wireless resources between base stations |
US10349418B2 (en) | 2015-09-16 | 2019-07-09 | At&T Intellectual Property I, L.P. | Method and apparatus for managing utilization of wireless resources via use of a reference signal to reduce distortion |
US9769128B2 (en) | 2015-09-28 | 2017-09-19 | At&T Intellectual Property I, L.P. | Method and apparatus for encryption of communications over a network |
US9729197B2 (en) | 2015-10-01 | 2017-08-08 | At&T Intellectual Property I, L.P. | Method and apparatus for communicating network management traffic over a network |
US10074890B2 (en) | 2015-10-02 | 2018-09-11 | At&T Intellectual Property I, L.P. | Communication device and antenna with integrated light assembly |
US9876264B2 (en) | 2015-10-02 | 2018-01-23 | At&T Intellectual Property I, Lp | Communication system, guided wave switch and methods for use therewith |
US9882277B2 (en) | 2015-10-02 | 2018-01-30 | At&T Intellectual Property I, Lp | Communication device and antenna assembly with actuated gimbal mount |
US10051483B2 (en) | 2015-10-16 | 2018-08-14 | At&T Intellectual Property I, L.P. | Method and apparatus for directing wireless signals |
US10355367B2 (en) | 2015-10-16 | 2019-07-16 | At&T Intellectual Property I, L.P. | Antenna structure for exchanging wireless signals |
US10665942B2 (en) | 2015-10-16 | 2020-05-26 | At&T Intellectual Property I, L.P. | Method and apparatus for adjusting wireless communications |
US9912419B1 (en) | 2016-08-24 | 2018-03-06 | At&T Intellectual Property I, L.P. | Method and apparatus for managing a fault in a distributed antenna system |
US9860075B1 (en) | 2016-08-26 | 2018-01-02 | At&T Intellectual Property I, L.P. | Method and communication node for broadband distribution |
US10291311B2 (en) | 2016-09-09 | 2019-05-14 | At&T Intellectual Property I, L.P. | Method and apparatus for mitigating a fault in a distributed antenna system |
US11032819B2 (en) | 2016-09-15 | 2021-06-08 | At&T Intellectual Property I, L.P. | Method and apparatus for use with a radio distributed antenna system having a control channel reference signal |
US10135146B2 (en) | 2016-10-18 | 2018-11-20 | At&T Intellectual Property I, L.P. | Apparatus and methods for launching guided waves via circuits |
US10340600B2 (en) | 2016-10-18 | 2019-07-02 | At&T Intellectual Property I, L.P. | Apparatus and methods for launching guided waves via plural waveguide systems |
US10135147B2 (en) | 2016-10-18 | 2018-11-20 | At&T Intellectual Property I, L.P. | Apparatus and methods for launching guided waves via an antenna |
US10811767B2 (en) | 2016-10-21 | 2020-10-20 | At&T Intellectual Property I, L.P. | System and dielectric antenna with convex dielectric radome |
US9991580B2 (en) | 2016-10-21 | 2018-06-05 | At&T Intellectual Property I, L.P. | Launcher and coupling system for guided wave mode cancellation |
US10374316B2 (en) | 2016-10-21 | 2019-08-06 | At&T Intellectual Property I, L.P. | System and dielectric antenna with non-uniform dielectric |
US9876605B1 (en) | 2016-10-21 | 2018-01-23 | At&T Intellectual Property I, L.P. | Launcher and coupling system to support desired guided wave mode |
US10340573B2 (en) | 2016-10-26 | 2019-07-02 | At&T Intellectual Property I, L.P. | Launcher with cylindrical coupling device and methods for use therewith |
US10312567B2 (en) | 2016-10-26 | 2019-06-04 | At&T Intellectual Property I, L.P. | Launcher with planar strip antenna and methods for use therewith |
US10225025B2 (en) | 2016-11-03 | 2019-03-05 | At&T Intellectual Property I, L.P. | Method and apparatus for detecting a fault in a communication system |
US10291334B2 (en) | 2016-11-03 | 2019-05-14 | At&T Intellectual Property I, L.P. | System for detecting a fault in a communication system |
US10498044B2 (en) | 2016-11-03 | 2019-12-03 | At&T Intellectual Property I, L.P. | Apparatus for configuring a surface of an antenna |
US10224634B2 (en) | 2016-11-03 | 2019-03-05 | At&T Intellectual Property I, L.P. | Methods and apparatus for adjusting an operational characteristic of an antenna |
US10340601B2 (en) | 2016-11-23 | 2019-07-02 | At&T Intellectual Property I, L.P. | Multi-antenna system and methods for use therewith |
US10535928B2 (en) | 2016-11-23 | 2020-01-14 | At&T Intellectual Property I, L.P. | Antenna system and methods for use therewith |
US10090594B2 (en) | 2016-11-23 | 2018-10-02 | At&T Intellectual Property I, L.P. | Antenna system having structural configurations for assembly |
US10178445B2 (en) | 2016-11-23 | 2019-01-08 | At&T Intellectual Property I, L.P. | Methods, devices, and systems for load balancing between a plurality of waveguides |
US10340603B2 (en) | 2016-11-23 | 2019-07-02 | At&T Intellectual Property I, L.P. | Antenna system having shielded structural configurations for assembly |
US10305190B2 (en) | 2016-12-01 | 2019-05-28 | At&T Intellectual Property I, L.P. | Reflecting dielectric antenna system and methods for use therewith |
US10361489B2 (en) | 2016-12-01 | 2019-07-23 | At&T Intellectual Property I, L.P. | Dielectric dish antenna system and methods for use therewith |
US10727599B2 (en) | 2016-12-06 | 2020-07-28 | At&T Intellectual Property I, L.P. | Launcher with slot antenna and methods for use therewith |
US10382976B2 (en) | 2016-12-06 | 2019-08-13 | At&T Intellectual Property I, L.P. | Method and apparatus for managing wireless communications based on communication paths and network device positions |
US10819035B2 (en) | 2016-12-06 | 2020-10-27 | At&T Intellectual Property I, L.P. | Launcher with helical antenna and methods for use therewith |
US9927517B1 (en) | 2016-12-06 | 2018-03-27 | At&T Intellectual Property I, L.P. | Apparatus and methods for sensing rainfall |
US10439675B2 (en) | 2016-12-06 | 2019-10-08 | At&T Intellectual Property I, L.P. | Method and apparatus for repeating guided wave communication signals |
US10135145B2 (en) | 2016-12-06 | 2018-11-20 | At&T Intellectual Property I, L.P. | Apparatus and methods for generating an electromagnetic wave along a transmission medium |
US10694379B2 (en) | 2016-12-06 | 2020-06-23 | At&T Intellectual Property I, L.P. | Waveguide system with device-based authentication and methods for use therewith |
US10020844B2 (en) | 2016-12-06 | 2018-07-10 | T&T Intellectual Property I, L.P. | Method and apparatus for broadcast communication via guided waves |
US10755542B2 (en) | 2016-12-06 | 2020-08-25 | At&T Intellectual Property I, L.P. | Method and apparatus for surveillance via guided wave communication |
US10637149B2 (en) | 2016-12-06 | 2020-04-28 | At&T Intellectual Property I, L.P. | Injection molded dielectric antenna and methods for use therewith |
US10326494B2 (en) | 2016-12-06 | 2019-06-18 | At&T Intellectual Property I, L.P. | Apparatus for measurement de-embedding and methods for use therewith |
US10389029B2 (en) | 2016-12-07 | 2019-08-20 | At&T Intellectual Property I, L.P. | Multi-feed dielectric antenna system with core selection and methods for use therewith |
US10168695B2 (en) | 2016-12-07 | 2019-01-01 | At&T Intellectual Property I, L.P. | Method and apparatus for controlling an unmanned aircraft |
US10359749B2 (en) | 2016-12-07 | 2019-07-23 | At&T Intellectual Property I, L.P. | Method and apparatus for utilities management via guided wave communication |
US10139820B2 (en) | 2016-12-07 | 2018-11-27 | At&T Intellectual Property I, L.P. | Method and apparatus for deploying equipment of a communication system |
US10446936B2 (en) | 2016-12-07 | 2019-10-15 | At&T Intellectual Property I, L.P. | Multi-feed dielectric antenna system and methods for use therewith |
US10243270B2 (en) | 2016-12-07 | 2019-03-26 | At&T Intellectual Property I, L.P. | Beam adaptive multi-feed dielectric antenna system and methods for use therewith |
US10027397B2 (en) | 2016-12-07 | 2018-07-17 | At&T Intellectual Property I, L.P. | Distributed antenna system and methods for use therewith |
US9893795B1 (en) | 2016-12-07 | 2018-02-13 | At&T Intellectual Property I, Lp | Method and repeater for broadband distribution |
US10547348B2 (en) | 2016-12-07 | 2020-01-28 | At&T Intellectual Property I, L.P. | Method and apparatus for switching transmission mediums in a communication system |
US10389037B2 (en) | 2016-12-08 | 2019-08-20 | At&T Intellectual Property I, L.P. | Apparatus and methods for selecting sections of an antenna array and use therewith |
US10326689B2 (en) | 2016-12-08 | 2019-06-18 | At&T Intellectual Property I, L.P. | Method and system for providing alternative communication paths |
US10069535B2 (en) | 2016-12-08 | 2018-09-04 | At&T Intellectual Property I, L.P. | Apparatus and methods for launching electromagnetic waves having a certain electric field structure |
US10938108B2 (en) | 2016-12-08 | 2021-03-02 | At&T Intellectual Property I, L.P. | Frequency selective multi-feed dielectric antenna system and methods for use therewith |
US10530505B2 (en) | 2016-12-08 | 2020-01-07 | At&T Intellectual Property I, L.P. | Apparatus and methods for launching electromagnetic waves along a transmission medium |
US10411356B2 (en) | 2016-12-08 | 2019-09-10 | At&T Intellectual Property I, L.P. | Apparatus and methods for selectively targeting communication devices with an antenna array |
US10916969B2 (en) | 2016-12-08 | 2021-02-09 | At&T Intellectual Property I, L.P. | Method and apparatus for providing power using an inductive coupling |
US10103422B2 (en) | 2016-12-08 | 2018-10-16 | At&T Intellectual Property I, L.P. | Method and apparatus for mounting network devices |
US10777873B2 (en) | 2016-12-08 | 2020-09-15 | At&T Intellectual Property I, L.P. | Method and apparatus for mounting network devices |
US10601494B2 (en) | 2016-12-08 | 2020-03-24 | At&T Intellectual Property I, L.P. | Dual-band communication device and method for use therewith |
US9911020B1 (en) | 2016-12-08 | 2018-03-06 | At&T Intellectual Property I, L.P. | Method and apparatus for tracking via a radio frequency identification device |
US9998870B1 (en) | 2016-12-08 | 2018-06-12 | At&T Intellectual Property I, L.P. | Method and apparatus for proximity sensing |
US9838896B1 (en) | 2016-12-09 | 2017-12-05 | At&T Intellectual Property I, L.P. | Method and apparatus for assessing network coverage |
US10340983B2 (en) | 2016-12-09 | 2019-07-02 | At&T Intellectual Property I, L.P. | Method and apparatus for surveying remote sites via guided wave communications |
US10264586B2 (en) | 2016-12-09 | 2019-04-16 | At&T Mobility Ii Llc | Cloud-based packet controller and methods for use therewith |
US9973940B1 (en) | 2017-02-27 | 2018-05-15 | At&T Intellectual Property I, L.P. | Apparatus and methods for dynamic impedance matching of a guided wave launcher |
US10298293B2 (en) | 2017-03-13 | 2019-05-21 | At&T Intellectual Property I, L.P. | Apparatus of communication utilizing wireless network devices |
WO2023131556A1 (en) | 2022-01-10 | 2023-07-13 | Signify Holding B.V. | A time-alignment subsystem and method for use with an optical transceiver |
Also Published As
Publication number | Publication date |
---|---|
US6426819B1 (en) | 2002-07-30 |
CA2249450A1 (en) | 1997-09-25 |
AU2332697A (en) | 1997-10-10 |
CA2249450C (en) | 2003-06-03 |
US5867292A (en) | 1999-02-02 |
CN1220789A (en) | 1999-06-23 |
JP2000507058A (en) | 2000-06-06 |
AU714753B2 (en) | 2000-01-13 |
IL126288A0 (en) | 1999-05-09 |
US5969842A (en) | 1999-10-19 |
EP0894374A1 (en) | 1999-02-03 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US5867292A (en) | Method and apparatus for cordless infrared communication | |
AU660077B2 (en) | Method and apparatus for optimum channel assignment | |
US4792984A (en) | Radio channel control method for mobile communication system | |
EP1063789A1 (en) | Transmit and receiving antenna diversity | |
EP1044518B1 (en) | An improved antenna diversity switching system for tdma-based telephones | |
US5548834A (en) | Radio telecommunication system with a multi-sensor receiver station and a plurality of emitter stations transmitting data packets | |
WO1997033389A1 (en) | Media access protocol for packet access within a radio cell | |
CN1068692A (en) | Set up the method and apparatus of a communication link | |
KR20000062519A (en) | Radio communication system | |
US4897864A (en) | Control method and appartus for a radio telephone system | |
AU724295B2 (en) | Method and device to determine the transmission point in time of a first transfer in relation to another transfer in a radio medium | |
CA2503248A1 (en) | Highly bandwidth-efficient communications | |
JPH10163936A (en) | Radio communication equipment | |
JP3389503B2 (en) | Base station equipment | |
KR970024667A (en) | A radiotelephone apparatus that performs spatial diversity reception to communicate with a base station using a TDMA wireless communication method. | |
AU691338B2 (en) | A method to adapt synchronous transmission | |
US5936947A (en) | Mobile communication system and control channel setting method in mobile communication system | |
US5293419A (en) | Simultaneous voice-call system for cordless telephone | |
JP3056087B2 (en) | Communication equipment and frequency change method of control channel | |
JPH0712232B2 (en) | Cordless telephone system | |
Andrisano et al. | Analytical model of busy channel multiple access (BCMA) for packet radio networks in a local environment | |
US6011972A (en) | Technique for setting cell coverage | |
JP2689953B2 (en) | Antenna control system | |
KR100473738B1 (en) | Wireless Transceiver Synchronization Method and Apparatus in Cellular System | |
JP3315790B2 (en) | Receiving unit management control method for multiple fixed stations |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
WWE | Wipo information: entry into national phase |
Ref document number: 97194748.1 Country of ref document: CN |
|
AK | Designated states |
Kind code of ref document: A1 Designated state(s): AL AM AT AU AZ BA BB BG BR BY CA CH CN CU CZ DE DK EE ES FI GB GE GH HU IL IS JP KE KG KP KR KZ LC LK LR LS LT LU LV MD MG MK MN MW MX NO NZ PL PT RO RU SD SE SG SI SK TJ TM TR TT UA UG UZ VN YU |
|
AL | Designated countries for regional patents |
Kind code of ref document: A1 Designated state(s): GH KE LS MW SD SZ UG AM AZ BY KG KZ MD RU TJ TM AT BE CH DE DK ES FI FR GB GR IE IT LU MC NL PT SE BF BJ CF CG CI CM GA GN ML MR NE SN TD TG |
|
121 | Ep: the epo has been informed by wipo that ep was designated in this application | ||
DFPE | Request for preliminary examination filed prior to expiration of 19th month from priority date (pct application filed before 20040101) | ||
ENP | Entry into the national phase |
Ref document number: 2249450 Country of ref document: CA Ref document number: 2249450 Country of ref document: CA Kind code of ref document: A |
|
WWE | Wipo information: entry into national phase |
Ref document number: PA/A/1998/007708 Country of ref document: MX |
|
WWE | Wipo information: entry into national phase |
Ref document number: 1997916058 Country of ref document: EP |
|
REG | Reference to national code |
Ref country code: DE Ref legal event code: 8642 |
|
WWP | Wipo information: published in national office |
Ref document number: 1997916058 Country of ref document: EP |
|
WWW | Wipo information: withdrawn in national office |
Ref document number: 1997916058 Country of ref document: EP |