Abstract: In a cellular communications system, the quality of a signal transmitted over a first two-way connection from a mobile station via a first base station is compared with a threshold to determine whether a handoff is to be performed to a second, adjacent base station. When the quality of the transmitted signal becomes lower than the threshold, a second two-way connection is established from the mobile station to the second base station, and a switching request signal and an information-bearing signal are sent from the mobile station over both connections to a switching exchange. In response to the request signal, one directional path of the first connection is cleared to prevent a version of the signal passing through the first connection from reaching the destination station, and a first switching complete signal is sent through the other path of the first connection to the mobile station to allow it to clear the first connection and return a second switching complete signal.

Abstract: In a geographic region that contains a trunking communication system and a cellular communication system, wherein the coverage area of each system substantially overlaps, a method that transfers a private call from the trunking communication system to the cellular communication is disclosed. When a communication unit initiates a private call in the trunking communication system, it transfers its affiliation from the trunking communication system to the cellular communication system. Once affiliated with the cellular communication, the private call is placed to the second communication unit. The trunking communication system detects the private call and instructs a second communication unit to transfer its affiliation to the cellular communication system. Once both communication units are affiliated with the cellular communication system, the private call is conducted. Once the private call ends, both communication units transfer their affiliation back to the trunking communication system.

Abstract: A system and method for communicating information signals using spread spectrum communication techniques. PN sequences are constructed that provide orthogonality between the users so that mutual interference will be reduced, allowing higher capacity and better link performance. With orthogonal PN codes, the cross-correlation is zero over a predetermined time interval, resulting in no interference between the orthogonal codes, provided only that the code time frames are time aligned with each other. In an exemplary embodiment, signals are communicated between a cell-site and mobile units using direct sequence spread spectrum communication signals. In the cell-to-mobile link, pilot, sync, paging and voice channels are defined. Information communicated on the cell-to-mobile link channels are, in general, encoded, interleaved, bi-phase shift key (BPSK) modulated with orthogonal covering of each BPSK symbol along with quadrature phase shift key (QPSK) spreading of the covered symbols.

Abstract: In an antenna arrangement system having a plurality of radio base stations each of which defines a cell approximated by a regular hexagon and divided into six sectors first and second ones of which are directed towards an angle of 0 degree with respect to an x-axis and towards an angle of 180 degrees, respectively, in an orthogonal coordinate system, first and second base stations are selected from the radio base stations to assign a common frequency channel to the first and the second sectors, respectively, and are located at first and second coordinate positions, respectively. The first and the second coordinate positions may be represented by (.sqroot.3 Rni, 3Rj/2) and (.sqroot.3 R(2ni-1)/2, 3Rj/2) where j takes an even number and an odd number, respectively, and R is representative of a real number, n, a natural number; i and j, integers. Alternatively, the first and the second coordinate positions may be represented by (.sqroot.3 Rni, 3Rj/2) and (.sqroot.3 R(3ni-3)/2, 3Rj/2) under the same conditions.

Abstract: The present invention provides a method for checking the degree of coverage in a mobile radio system. According to the method, field strengths are utilized which have been measured from all base stations for all important traffic routes in the mobile radio system. The field strength values are related to geographical coordinates in a respective coverage area and the highest value for each coordinate is stored. The values noted are then compared with a predetermined coverage limit value. With the aid of the method, a graph can be produced using the field strength values stored for each coordinate, the coordinates which are lower or higher than the coverage limit value being marked in the graph.

Abstract: A mobile communication system in which overlapping location areas are defined by radio base stations on an autonomous distribution basis. In a first embodiment, a mobile station registers the location thereof when moved in a radio zone which is not included in a location area notified by a radio base station and held therein. In a second embodiment, the mobile station registers the location when entered a radio zone in which location area being notified by the radio base station does not include the radio zone where the mobile station registered the location last. In a first and a second embodiment, the mobile station memorizes radio zones which it has passed after location registration as route information and may report the route information to a radio base station in the event of next location registration. The radio base station sequentially includes in the location area the radio zones which frequently appear in the route information.

Abstract: A wireless-access communications system, such as a CDMA cellular radio-telephone system (FIG. 2), comprises a packet-switched communications network (202, 207, 201) that interconnects cells (base stations; 202) with each other and with the public telephone network (100). Traffic of individual calls is packetized, and packet-bearing frames (300 in FIG. 7) of a plurality of calls are then statistically multiplexed and frame-relayed through the network to yield the high capacity, efficiency, and speed of traffic transport and handoff required for a CDMA cellular system. At each call processing unit (264 in FIG. 5), individual calls are handled by individual service circuits (602 & 612) which perform speech-processing functions such as coding and decoding, tone insertion, and echo cancellation, and packet-to-circuit-switched-PCM traffic conversion.

Abstract: A low-power digital frequency synthesizer combining direct digital frequency synthesis techniques with serrodyne frequency translation principles to produce a wideband frequency response with high spectral purity. A conventional direct digital synthesizer is used to generate a high-resolution analog carrier signal from a low-speed digital clock signal. The carrier signal is phase modulated by a low-resolution signal generated from a high-speed digital clock signal. The modularity signal is a higher frequency signal than the carrier signal. The phase modulation is accomplished by exact decoded attenuators. The spectral purity of the resulting high-resolution output signal is unobtainable by conventional direct digital synthesizers, while providing significant power savings.

Abstract: An integrated PCN/DCN system architecture has a switching center, coupled to a public switched telephone network (PSTN), which selectively transfers signals between the PSTN and a digital cellular network (DCN) or a personal communications network (PCN) which is allocated a portion of the cellular communications band by a local cellular operator. Each PCN subnetwork of the PCN includes several microcells arranged in a multi-dimensional grid, and the allocated cellular channels are divided into sets assigned to columns of the grid. The allocated portion of the cellular spectrum is reused within each PCN subnetwork by assigning the same set to more than one of the columns so that different communications signals can be transferred over the same cellular channels.

Abstract: Method and apparatus for use in a mobile telephone rental system in which credit card information is communicated between the mobile telephone unit 100 and a Voice Response System 302 for customer registration and remote programming of mobile telephone unit 100 features and NAM settings; communicating data between the Voice Response System 302 and a Registration System 304 for customer credit card validation; communicating data between the Registration System 304 and a credit card clearinghouse 306 for credit card approval or decline; communicating data between the Registration System 304 and a plurality of Collector Systems 307 for call rating and billing; communicating data between the Registration System 304 and an Administration System 309 for providing rated call information to the reseller; and communicating data between the mobile telephone unit 100 and an Indirect System 303 for establishing service in cellular areas without Collector System 307 service.

Abstract: A bulletin board communication resource provides a message to communication units regarding available communication systems in a particular geographic area. The bulletin board resource also supports registration of the communication unit with one or more of these systems as selected by the communication unit.

Abstract: A satellite based paging communication system comprises a plurality of terrestrial stations capable of communicating the paging information with at least one satellite. The satellite(s), in turn, are capable of communicating the paging information to at least one terrestrial receiver or terrestrial station. Also included is at least one control station for determining where and how to deliver the paging information to one or more of a plurality of terrestrial receivers (pagers), at least some of which are capable of receiving the paging information from one or more of the satellites and one or more of the terrestrial stations.

Abstract: In a TDMA cellular network, there is provided a mechanism for shared-carrier frequency-hopping. It comprises: allocating on a frame basis within a reuse diameter to one coverage area during certain timeslot(s) at least one from a pool of TDM-frame-hopped carriers and allocating on a frame basis within that carrier reuse diameter to another coverage area during certain other, substantially non-overlapping timeslot(s) that frame-hopped carrier, all in substantially non-interfering time-synchronism with any proximal reuse of that carrier, whereby the advantages of frequency hopping are obtained. Stated differently, it comprises: at one instant in time, allocating within a reuse diameter to one coverage area at least one of a plurality of hopped carriers and at that same instant in time, allocating within that carrier reuse diameter to another coverage area another of that plurality of hopped carriers, all in time-synchronism with any proximal reuse of that carrier.

Abstract: In the course of the intercommunication between the base station and the autonomous telephone set, the first means of authentication initially generates a keyword dependent on the call charge for the current service and transmits it to the autonomous telephone set. The second means of authentication then calculates the transform of the keyword by the encryption function F with the aid of the subscriber's secret key, and transmits the transform to the first means of authentication which finally checks the authenticity of the transform to totally block the intercommunication if the authenticity is not confirmed by the check.

Abstract: A mobile telephone system multiplexes plural voice traffic channels on a single carrier using a TDMA protocol. The capacity of the mobile telephone system is increased by assigning voice traffic capacity, not on a conversation basis, but on a speech spurt basis. In order to avoid compromising the voice transmission capacity, control signals (for the allocation and deallocation of both forward and reverse traffic channels) are sent using multiple diversity, i.e. both time and frequency. In addition, to increase the number of available control channels, a control channel comprises a sub-divided portion of an otherwise equivalent voice traffic slot. For reverse allocation requests, which are transmitted over a contention access channel, power diversity is used in addition to time and frequency diversity.

Abstract: A two-stage planetary gear transmission having a first-stage planetary gear transmission and a second-stage planetary gear transmission is disclosed, wherein the carrier of the second-stage planetary gear transmission comprises first and second carrier parts integrally connected with each other. A hollow pinion shaft formed thereon with the sun gear of the second stage is rotationally supported on the first carrier part via a deep-channel ball bearing in a cantilevered condition. A carrier of the first stage for supporting planetary gears of the first stage is integrally formed on the end of the hollow pinion shaft of the second stage. A lubricant layer of about 15 .mu.m to about 20 .mu.m in width is formed between an inner race member of a planetary bearing and a planetary shaft for each of the planetary gears of the second stage.

Abstract: Reception of a transmission in a radiotelephone system including an equalizer is improved by training the equalizer using a synchronization portion of the transmission having a data pattern chosen for its correlation properties and retraining the equalizer using a portion of the transmission transmitted for a different purpose. In particular, the portion of the transmission transmitted for a different purpose may be the digital verification color code transmitted during each burst in a digital cellular mobile radiotelephone system. Reception quality is increased by training the equalizer at more frequent intervals without increasing transmission overhead.

Abstract: An advanced telecommunications system is provided for the recognizing of spoken commands over a cellular telephone, satellite telephone, or personal communications network. In the cellular application, for example, a Speech Recognition System interconnects either internally with or as an external peripheral to a cellular telecommunications switch. The Speech Recognition System includes an administrative subsystem, a call processing subsystem, a speaker-dependent recognition subsystem, a speaker-independent recognition subsystem, and a data storage subsystem. The Speech Recognition System also allows for increased efficiency in the cellular telephone network by integrating with the switch or switches as a shared resource. The administrative subsystem of the Speech Recognition System is used to keep statistical logs of pertinent call information. Pre-recorded instructional messages are stored in the memory of the call processing subsystem for instructing a user on his or her progress in using the system.

Abstract: A method and system for increasing the capacity of radiotelephone communication systems by eliminating interference to communication traffic caused by random access bursts from unconnected mobile station are disclosed. Access slots are provided in CDMA signals by interrupting other communication traffic of mobile stations using the same frequency at periodic intervals. This allows mobile access bursts to be received at a base station without interfering with other traffic.

Abstract: A system for marking a plurality of zones within a cellular service area. One or more marker transmitters are disposed throughout a cellular area to transmit a zone identification signal that is independent of normal RF cellular coverage to a mobile or portable cellular receiver. Each zone identification signal is transmitted in a radio frequency coverage area that illuminates the zone to be identified and is constrained by a similar transmitter jamming the zone signal. The marker transmitters are programmed to transmit the zone identification signal during a predefined time slot so that more than one marker transmitter may simultaneously transmit the zone identification signal, thereby increasing the area in which the zone identification signal can be received by the mobile unit. In order to reduce the area in which a zone identification signal may be received by a mobile unit, the marker transmitters may transmit a jamming signal at the same time as the zone identification signal is transmitted.

Abstract: A method of providing an estimation of a mobile station's location in a cellular communication system having a plurality of base stations and mobile stations is disclosed. The mobile station's location is provided by measuring radio propagation parameters between the mobile station and each base station within propagation range of the mobile station. Then, a location probability density function (pdf) is found based on the measured radio propagation parameters. A joint probability density function (pdf) is then constructed by combining each individual function which is obtained. The location of the mobile station is then estimated from the resulting joint probability density function (pdf).

Abstract: A synchronizing method in a mobile radio system which operates with Time Division Multiple Access (TDMA) but which lacks global time reference for all base stations and mobiles in the system. The inventive method is intended for ciphered transmission of data and speech in accordance with a given ciphering key (E2). When handing-over a call, the ciphering synchronism is lost. In accordance with the method, subsequent to hand-off (the time t.sub.2), the take-over base station (BS2) signals non-ciphered information (S1) to the mobile (MS) disclosing the number of frames (R1-R13) which shall pass until ciphering can again be commenced, calculated from a given frame (R1). Call information is transmit the following frame (R2), this information now being ciphered with the aid of a ciphering key (E1) different to the original key. This other ciphering key consists of a periodic bit sequence having a period which is equal to one frame interval.

Abstract: In a mobile radiotelephone system, a base station, upon receiving a service request from a mobile station, ascertains whether the service request can be accepted according to the availability of voice channels in the base station, and, if the service request cannot be accepted, compares a measured signal strength of the service request with at least one threshold value. If the signal strength exceeds the threshold, the mobile station is directed to retry the service request on one or more of a first set of channels assigned to neighboring base stations. Otherwise, the mobile station is directed to retry the service request on one or more of at least a second set of channels assigned to neighboring base stations. Accordingly, directed retries nearer the interior of a cell may be restricted or eliminated, whereas directed retries toward the periphery of the cell may be freely allowed or less severely restricted.

Abstract: The present invention relates to a method for planning radio cells. The method utilizes an exclusion matrix calculated on the basis of measured field strengths and an iterative allocating algorithm, which allows an adaptation of the cell planning to prevailing traffic demand.

Abstract: A distance based method for mobile station registration in a cellular communication system. The mobile station registers whenever it moves into a new cell that is greater than some predefined distance from the previous cell where it registered. Cell base stations transmit corresponding base station location information and a distance value. The mobile station receives the base station location information and computes the distance from a cell in which the mobile station last registered to the current cell in which the mobile station is present. When the computed distance is greater than the distance value associated with the registration cell the mobile station registers. Pages for the mobile station are transmitted within a group of cells within a distance of the registration cell corresponding to the registration cell transmitted distance value.

Abstract: A satellite communication system (1110) provides geographic protocol conversion for message delivery between communication transceivers (1118, 1118') operating within at least two geographic areas (1116, 1116'). The satellite based communication system (1110) comprises a first communication transceiver (1118) which provides two-way message delivery within a first radiotelephone network (1114) located within at least a first geographic area (1116), the two-way message being encoded in a first predetermined message transmission protocol. The first communication transceiver (1118) further enables two-way message delivery with a communication satellite (1120), the message also being encoded in the first predetermined message transmission protocol.

Abstract: A method is offered of achieving a desired C/I ratio within a cellular system, at reduced transmitter power levels, by measuring a signal loss on a downlink between a base site transmitter (31) and mobile receiver (20) and calculating an uplink signal magnitude at a base site receiver. A communication channel is then selected from a number of communication channels based upon comparison of the uplink signal magnitude with pre-measured interference levels for each channel of the number of channels to produce a desired C/I ratio.

Abstract: An apparatus and method for issuing busy call-backs (146) on the voice channel to busied communication units (209,211) on a trunked radio communication system (200) is disclosed. This is accomplished, in part, by issuing a busy signal (104), via a control resource (203), to a communication unit when a requested communication resource is unavailable. Additionally, the radio communication unit (209,211) is capable of receiving the busy signal via the control resource (213) and participating in a second communication while in a busied state. The resource controller (201) is capable of allowing the busied communication unit (209,211) to participate in a second communication on a second communication resource (215) and issuing the call-back signal during the second communication.

Abstract: According to the cellular mobile radiotelephone call access method of the present invention, a directed retry message is sent in response to an attempted call access in a first cell experiencing congestion. A subsequent retry and a second cell of the attempted call access is detected, and, if a traffic channel allocated to the first cell is then available, a traffic channel allocated to the first cell is assigned from the second cell. The call is therefore established in the original cell more often, and interference is reduced.

Abstract: The present invention provides a mobile communications system in which the home exchange of a mobile subscriber maintains information indicative of where the mobile subscriber might be found. Upon receipt of a call, the home exchange requests the exchange where the mobile is believed to be located to page it and then requests the answering exchange(s) to order the mobile to tune to a voice/traffic channel. Only after the successful completion of this process does the answering exchange report this to the home exchange which then orders routing of the call through the network.

Abstract: Methods for carrying out an authentication check in a mobile telephone system in which an authentic base station serves a plurality of mobile stations. A prior method carried out a unidirectional check from the base to a calling mobile, permitting a false base to carry out a false authentication check by collecting a number of so-called RAND-Response pairs. To avoid this problem, another unidirectional, base-to-mobile, authentication check and an authentication check from the mobile to the base are carried out. In one embodiment, only the bi-directional authentication check is carried out.

Abstract: An emergency alerting system for alerting or warning large numbers of people of the occurrence or threat of an emergency using available communications media. Multiple facilities are monitored for the occurrence of multiple alarm conditions. On the occurrence of such a condition radio or telephone contact is made with a Local Emergency Planning Committee (LEPC) and the LEPC is notified of the site and nature of the alarm condition. Using a predetermined listing or data bank the LEPC selects a number corresponding to the site and condition and transmits such number to an automated controller for a radio transmitter. The transmitter may be part of an existing radio paging system. The automated controller, on the basis of the number dialed in by the LEPC, transmits an appropriate Code Assignment Plan (Cap Code) signal. The Cap Code signal is the electronic signature of a preprogrammed Cap Code chip within individual radio receivers positioned at the sites of intended alarm recipients.

Abstract: System synchronization is achieved in a system of remote stations serving a particular cell site or base station by combining rf signals transmitted to the base station from the cell site with a reference signal to form a composite signal. This composite signal is used to modulate the output of a base station laser transmitter. The composite signal is transmitted to the remote station where the reference frequency is extracted and used to synchronize the rf circuits of the remote station. Special diagnostic features are built into the remote station transceivers so that equipment functioning may be monitored at the base station.

Abstract: In a cellular radiotelephone communication system, there is provided a method and apparatus for reducing contention between a plurality of mobile units requesting system resources comprising the steps of A) receiving access requests from at least one of the plurality of mobile units, B) determining the number of attempted access requests (access request count); and C) altering system resources as a function of the access request count in order to reduce the likelihood of contending mobile units. An alternative embodiment suggests deriving timing advance information as well as access request count, correlating the access request count to the timing advance information, and altering system resources as a function of the correlation in order to reduce the likelihood of contention. Yet another embodiment suggests that the mobile unit take independent action, based upon its access request count, in order to reduce the likelihood of contention.

Abstract: A private mobile radio transmission system comprising a plurality of geographically spaced base stations (BS) defining a plurality of overlapping service areas (SA). The base stations are coupled for example by land-line communication links (CL) to a system controller (SC). Mobile stations (MS) equipped with simplex two-way radios are free to roam through the service areas. In order to be able to make a call with or via a base station it is necessary for the mobile station to be registered with the base station concerned. Details of the registration are stored by the mobile station concerned and the base station.

Abstract: A mobile radio communication system according to the invention comprises a base station to be connected with a communication network by way of a wired communication path, a mobile base device to be connected with the base station by way of a first radio channel selected from a plurality of first radio channels and a portable device to be connected with the mobile base device by way of a second radio channel selected from a plurality of second radio channels. Each of the first and second radio channels defined by a radio frequency and a time slot. The mobile base device comprises first, second and third connection control circuits. The first connection control circuit is used to select an idle first radio channel out of the first radio channels in cooperation with the base station and connect the mobile base device with the base station by the selected idle first radio channel.

Abstract: A method of providing local autonomous control of channel allocation of a cellular telecommunications network. In one prior art method, which can be identified as the timid method, a channel is selected for use by an incoming user if it is not being used by any of the cells which surround it. Otherwise, another channel is selected according to the same rule. The channels are tested in random order and a call is blocked if all of the channels are in use. For heavy loading, because of the vagaries of the way the demand for channels occurs, this method can result in inefficient channel deployment. In another method, which can be identified as the aggressive method, a channel is selected for use by an incoming user even if that channel is currently being used in the surrounding cells. If the channel is in use, the incoming user "bumps" the current user off the channel in the timid mode. The "bumped" user is then forced to find and use another channel.

Abstract: A selective call receiver transmission system for transmitting a message to at least one selected selective call receiver of a plurality of selective call receivers comprises a transmitter for transmitting information including the message thereto. At least one satellite receives the information and transmits the message to the selective call receiver and subsequently retransmits the message from a different location to the selective call receiver.

Abstract: An improved method is disclosed for automatically updating databases contained in the random access memory and tape storage of a cellular switch. First, instructions are issued to a cellular switch, causing the switch to provide a first output of one or more operative databases contained in the random access memory of the switch. Then, one or more backup databases are loaded into the random access memory of the switch, and instructions are issued to the switch causing the switch to provide a second output of the backup databases. The first and second outputs are then analyzed by a computer program, and in response to the analysis the program automatically assembles a number of cellular switch compatible software commands into a text file. Finally the text file is transmitted to the switch, thereby updating databases contained in the random access memory and the tape storage of the switch.

Abstract: Orbiting satellites project footprints on the earth. Each footprint is divided into cells. Footprints of nearby satellites overlap one another, and the overlap increases as satellites approach a pole from the equator. The positions of all cells generated by all satellites are simulated at numerous points throughout an orbit. Cells are marked as being active or inactive to compensate for the overlap at each simulated point. Channel sets are assigned to cells within a reference footprint, and this assignment is propagated throughout all footprints in the referenced footprint's orbit. The channel set sequences are propagated to other orbits after taking into account inactive cells located near boundaries between the orbits. Each satellite stores channel set assignments for its cells at the various points throughout its orbit. All satellites switch their communication parameters at the same instant in response to the channel set assignments.

Abstract: A power control system for a cellular mobile telephone system in which system users communicate information signals between one another via at least one cell site using code division multiple access spread spectrum communication signals. The power control system controls transmission signal power for each cellular mobile telephone in the cellular mobile telephone system wherein each cellular mobile telephone has an antenna, transmitter and receiver and each cell-site also has an antenna, transmitter and receiver. Cell-site transmitted signal power is measured as received at the mobile unit. Transmitter power is adjusted at the mobile unit in an opposite manner with respect to increases and decreases in received signal power. A power control feedback scheme may also be utilized. At the cell-site communicating with the mobile unit, the mobile unit transmitted power is measured as received at the cell-site.

Abstract: In a code division multiple access (CDMA) spread spectrum cellular communication system in which a mobile station user communicates with another system user via at least one base station, wherein each base station transmits a common pilot signal of a different code phase with respect to other base stations in said system, a method for directing communications between said mobile station user and said base stations. The mobile station monitors the signal strength of pilots and reports the measured signal strength to a system controller via the base station through which it is communicating. Command messages from the system controller to a new base station and the mobiles station establishes communication through the new base station in addition to the communication through the current base station.

Abstract: A power control system for a cellular mobile telephone system in which system users communicate information signals between one another via at least one cell site using code division multiple access spread spectrum communication signals. The power control system controls transmission signal power for each cellular mobile telephone in the cellular mobile telephone system wherein each cellular mobile telephone has an antenna, transmitter and receiver and each cell-site also has an antenna, transmitter and receiver. Cell-site transmitted signal power is measured as received at the mobile unit. Transmitter power is adjusted at the mobile unit in an opposite manner with respect to increases and decreases in received signal power. A power control feedback scheme may also be utilized. At the cell-site communicating with the mobile unit, the mobile unit transmitted power is measured as received at the cell-site.

Abstract: A system, and associated method, for measuring a signal level of a signal received by a receiver, such as a radio telephone. The signal received by the receiver is applied to a variable amplifier. The amplification of the variable amplifier is adjusted such that an amplified signal generated therefrom is within the dynamic range of an intermediate frequency circuit. The level of amplification required to position the signal level of the amplified signal within the dynamic range of the intermediate frequency circuit is measured, and the signal level of the signal received by a receiver is calculated.

Abstract: In a cellular mobile telephone system serving a plurality of cells, each of the cells being assigned a unique standby channel, the mobile station is assigned several standby channels and a system identifier identifying the system. The standby channels are scanned and one of the scanned channels having a highest signal level is selected. If there is a match between the system identifier of the selected standby channel and the system identifier of the mobile station, the mobile station is ready to originate or receive a call. If there is no originating or incoming call, the identifier of a call setup channel specified by the standby channel is stored into a different location of a memory. Otherwise, the identifiers stored in the memory are scanned, and one of the scanned call setup channels is selected.

Abstract: For setting up LOS radio links between mobile calling transmitting/receiving stations and other mobile or stationary remote transmitting/receiving stations in a predetermined operating area, especially in the frequency range above 1 GHz, every mobile station is provided with an electronic memory with an associated processor. The memory stores the respective geographical and topographical data of the operating area. Prior to the setting-up of a radio link, the transmission loss between the stations is calculated in accordance with known model calculations on the basis of the geographical and topographical data stored in the memory by inputting into the processor the current location data of the calling station and the remote station.

Abstract: A method and apparatus for use in a cellular mobile radio telephone system for determining which of one of several mobile generated transmissions received in a mobile switching center, sent from the same mobile station via more than one base station, should be accepted. A determination is made based on the relative signal strengths of the signals received by the base stations and by the relative time of occurrence of the mobile generated transmissions.

Abstract: In a cellular radiotelephone network, there is provided a mechanism for dynamic frequency reuse. It comprises: allocating according to one reuse pattern during one time interval at least one of a plurality of hopped carriers and allocating according to another reuse pattern during another, substantially non-overlapping time interval that hopped carrier, all in substantially non-interfering time synchronism with any proximal reuse of that carrier. The attendant advantage is the realization of a dynamically allocatable frequency reuse, using shared carriers and frequency hopping to provide the desired C/I performance.

Abstract: A mobile data telephone capable of transmitting and/or receiving voice and/or data signals over cellular communication channels or other air interfaces comprises a radio transceiver and a data modem in the same physical package. The transceiver and the modem have their respective controllers coupled so that they are effectively linked to achieve control of data transfer therebetween. In response to communication channel conditions in the air interface, the data flow between the modem and an audio processor of the transceiver can be selectively altered yielding high performance and high quality data transfer rates in the presence of severe channel impairments.

Abstract: A self-contained cellular emergency roadside call box is disclosed without the use of external telephone lines. The call box is solar powered with battery storage and comprises a controller coupled to a cellular transceiver. The controller is also coupled to a solar array and battery which is recharged through the controller. The call box communicates through a radio-telephone link established by the cellular transceiver to a cellular telecommunication system. The cellular telecommunication system includes a call site controller and mobile telephone switching terminal. Each call box comprises a plurality of status subcircuits for monitoring conditions such as battery condition and transmitter status. The call box communication and the status are processed by a micro processor which generates appropriate commands required by the cellular transceiver. Information can be transmitted bidirectionally between each of the call boxes and the communication applications processor.