Abstract: In multiplexed data radio communication, especially (but not exclusively) in TDMA mode, a method is provided of offering optimized intelligent traffic channel sharing services, enabling data from a secondary source to be conveyed on a traffic channel assigned to a main source (20, 30, 40). Each of the blocks transmitted by the main source and the data from the secondary data source are defined by one of the least three relative levels of importance (NI.sub.p =0, 1 or 2; NI.sub.s =0, 1, or 2). Data from the secondary source is substituted for a block transmitted by the main source as the result of a comparison of the respective relative levels of importance of data from the secondary source and the block from the main source.

Abstract: The invention relates to a method of determining the distribution of marginal traffic capacity of given cells in a radio cell system comprising base stations with associated coverage areas and radio stations within the coverage areas of the cell. Compatibility calculations are performed for each element or a selective selection of elements of an exclusion matrix. The channels are redistributed in this way iteratively in dependence of the time dependent traffic need in each cell.

Abstract: A paging system (10) includes any number of spaced apart transmitters (12), each of which has its own area (15) of coverage. A population of subscriber units (24) freely roams between the areas (15). When a subscriber unit (24) roams to a new area (15), a call is placed from a telephone instrument (22) to a destination controller (28) through the public switched telecommunication network (21). A subscriber ID and location data are transferred to the system (10) during this call. The location data are used internally by the system (10) to route pages to only the transmitters (12) whose areas (15) correspond to the location data, and only these transmitters (12) broadcast the pages. Subscriber units (24) may generate the location data which the system (10) uses in routing pages to transmitters (12). A position-determining receiver (42) may directly obtain location data from a positioning system (34). Alternatively, location data may be obtained from transmissions broadcast by the transmitters (12).

Abstract: A radio frequency backbone communication system is offered for exchanging, a plurality of communicated signals between a central site (205) and a plurality of communication units (16-18) through a plurality of remote base sites (60-66). The system includes at least one mobile function transceiver (201-204) located at the central site (205), transceiving a communicated signal of the plurality of communicated signals on a shared communication resource of a base site of the plurality of base sites (60-66) and, means for synchronizing a transceiver at the base site to the communicated signal of the at least one mobile function transceiver (201-204).

Abstract: A method in a cellular communication system provides selection of a channel for use in a pending communications operation, the selection reducing the likelihood of co-channel interference. In each co-channel cell, frequencies from the cell's frequency group are ordered in a sequence. A different frequency in each cell is designated as having a highest priority. Successively lower priorities are then assigned, in each cell, to remaining frequencies in sequence. Then, in each cell, selection is made by identifying the available frequency having the highest priority. The method may be modified to provide for even distribution of hardware use by changing the priorities in each cell periodically. The method may also be modified for use in a fully synchronized time division multiple access (TDMA) system by performing the above steps with respect to channels instead of frequencies. The method may further be modified for use in a pseudo-synchronized TDMA system (i.e.

Abstract: A cellular voice privacy arrangement includes a digital privacy unit which is part of each subscriber's fixed equipment. The digital privacy unit includes suitable analog to digital and digital to analog converters. A vocoder, digital signal processor and modem provide the privacy. The identification numbers of each terminal (phone) are exclusive-ORed to form a scramble variable. Vocoder data (voice coded information) is exclusive-ORed with the scramble variable to provided scrambled data for transmission.

Abstract: In methods and apparatus for estimating carrier-to-interference ratios of signals transmitted between cellular radio base stations and mobile units, a SAT signal is transmitted from a base station to a mobile unit served by that base station. The mobile unit receives the SAT signal and retransmits the received SAT signal to the base station. A first order autoregressive parameter is calculated for the received SAT signal at the base station is correlated with a tabulated carrier-to-interference ratio estimate to estimate the carrier-to-interference ratio of the signals.

Abstract: A cellular radio system has a plurality of base stations (BS) each for communicating with mobile stations (MS) in its vicinity, and each base station (BS) determines that voice or data communication between the base station and the mobile station has temporarily ceased, and initiates required signalling with the mobile station during that temporary cessation.

Abstract: A system and method for reducing amplitude distortion in a data signal transmitted through a cellular analog communication system is embodied in several forms. Each specific embodiment of the invention eliminates distortion caused by clipping or sluggish recovery time induced by a limiter circuit which exists in conventional cellular communication systems. In one embodiment, pre-emphasis and de-emphasis functions of the cellular system are offset by complementary de-emphasis and post-emphasis circuits so that the high frequency components of the data signal are not clipped by the limiter. In another embodiment, the limiter circuit is bypassed selectively when a data signal is transmitted. In an alternative embodiment, a pilot tone is combined with the incoming data signal. The characteristics of the pilot tone are such that amplitude of the pilot tone is constant and always sets the gain of the limiter, thereby keeping the gain of the limiter circuit constant.

Abstract: The Advanced Intelligent Network (AIN) wireline system connects to and controls processing of calls to a Personal Communication Service subscriber's wireless handset via a home base station or a wireless communication network. Depending on its current location, the subscriber's handset automatically registers with the base station or with a mobility controller of the wireless network. A new registration with the base station when the handset comes within range causes that station to update the subscriber's home location register in a central data base of the AIN. Similarly, when a handset first registers with a mobility controller, that controller updates the subscriber's home location register in the central data base of the AIN. In response to calls directed to the subscriber, the AIN accesses the home location register to determine the current location where the handset is registered. The AIN then uses that data to route the call to the current location.

Abstract: A personal communications system permits a wireless handset to access either a cellular mobile telephone system (CMTS) or a private wireless telephone system (WTS) which shares the CMTS frequency band by utilizing those CMTS channels which are idle in the area serviced by the WTS. The wireless handset automatically selects between the WTS and CMTS operating modes by maintaining a list of previously accessed WTS control channels and periodically scanning that list for a WTS available at the location of the handset. If a WTS control channel is not found in that list, then the handset periodically scans all possible WTS control channels for the purpose of registering on an available WTS. If no WTS is found, then the handset switches to CMTS mode. The scanning methodology permits the wireless handset to rapidly lock on to an available WTS which will provide service to the handset, so as to reduce the possibility of the wireless handset missing incoming paging signals.

Abstract: In a satellite cellular communication system, subscriber unit traffic within any cell is managed by changing the signal level of the broadcast channel of the cells. Subscriber units located within the cells monitor the signal levels of the broadcast channels and initiate handoff requests when the signal level of the cell in which the subscriber unit is located falls below the signal level. As demand for communication services within a cell approaches the maximum capacity of the cell, the communication system reduces the signal level of the broadcast channel within the cell encouraging subscriber units within that cell to seek service from other cells. Thus the apparent cell size is reduced as to the subscriber units within the cell.

Abstract: A system for allocating communication channels within a cellular radio system in which each channel seizure request is assigned a call type based upon the capabilities of the mobile station, the nature of the call and the characteristics of the subscriber. A first algorithm is used to select a communication channel group for the call and a second algorithm is used to select an available communication channel from within the selected channel group.

Abstract: Cellular mobile communication system includes a plurality of base stations connected to a relay station, each base station having adaptability for coping with change in traffic volume within a relevant cell covered thereby. Each base station includes a variable gain power amplifier for amplifying a pilot signal and a power control circuit for controlling the gain of the power amplifier. The power control circuit controls gain of a pilot signal sending power in accordance with a control signal supplied from a device installed in a relay station for monitoring traffic states of the individual base stations. The relay station issues a command for lowering the power gain for the base station which covers a traffic-concentrated cell while raising the power gain for the base stations covering the neighboring cells, to thereby contract the size of the traffic-concentrated cell. With a smaller number of base stations, communication demand can be controlled over a broad area.

Abstract: A system for enhanced call delivery to a roaming cellular subscriber, enabling said subscriber to receive calls placed to his MIN in his home system service area, utilizes a central telecommunications system processor capable of handling network applications, directly connected to a plurality of mobile telephone switches located in the service areas of a plurality of cellular telephone systems, each of said switches connected via a direct communication link to said central telecommunications system processor. A plurality of registers in said central telecommunications system processor are provided for storing data bases of system information, individual switch information, and subscriber information.

Abstract: A method for assigning frequency channels to base stations in a cellular communication system that coexists with a set of existing fixed site microwave receivers groups the base stations into clusters and the potential frequency channels into channel blocks. Each cluster is then assigned a usage parameter indicative of how many base stations within the cluster may operate within a given channel block. A computer model is operated to predict whether aggregate interference from the base stations and the associated handsets at the existing fixed site receivers would be excessive. If so, the usage parameters are revised to reduce the number of base stations within the respective cluster that may operate within an interfering channel block. These steps are repeated until the aggregate interference from the base stations and associated handsets at the existing fixed site microwave receivers is no longer excessive.

Abstract: A system for accessing a telephone system, in which a set of user stations are matched with a set of base stations for connection to a telephone network. Each base station may be coupled directly or indirectly to the telephone network and may be capable of initiating or receiving calls on the telephone network. Each user station may comprise a spread-spectrum transmitter or receiver and may be capable of dynamic connection to selected base stations. A plurality of base stations may be coupled to a private exchange telephone system for coupling user stations in calls outside the telephone network. User stations may use CDMA, FDMA, TDMA or other multiple-access techniques to obtain one or more clear communication paths to base stations. Base stations may be placed at convenient locations or may themselves be mobile. User stations may make and break connections with base stations as the user station moves between service regions, or is otherwise more advantageously serviced by, base stations.

Abstract: A mobile radio communication system is provided with a base station apparatus connected to a wire circuit, a mobile radio station apparatus which is connected to the base station apparatus by means of a radio circuit, a mode designation device for selecting either an analog mode or a digital mode when radio communication is to be performed between the base station apparatus and the mobile radio station apparatus, and a mode-informing device for informing the base station apparatus of the mode designated by the mode designation device.

Abstract: A modulation apparatus for a cellular radio system in which capacity is increased and power consumption is minimized, said system covering large and small area cells of different sizes. At least two different modulation schemes are used in the system. For large area cells, constant envelope modulation is used for minimizing power consumption, and for small area cells, linear modulation is used for minimizing the channel spacing, and in this manner, for increasing the cellular capacity.

Abstract: A method and system for the adaptive allocation of channels within a radio communication system, specifically a cellular network, is presented. The allocation method takes advantage of measurements made by the mobile radiotelephone and allocates channels based on the carrier to interference ratio. Using adaptive power control, consideration is given to maintaining an acceptable carrier to interference ratio while at the same time minimizing transmit power. Exemplary embodiments consider independent allocation of the uplink and downlink as well as independent determination of the uplink and downlink power levels. Other exemplary embodiments also give consideration to an efficient method for slot allocation in a TDMA communication system.

Abstract: A cellular motor control network including a service center and a plurality of local cell controllers in communication with the service center, with each of the plurality of local cell controllers having a plurality of cellular motor controls in communication therewith. Each cellular motor control coupled to a variable speed electric motor. The cellular motor control including control circuits for controlling the operation of the variable speed electric motor, a microprocessor coupled to the control circuits for providing a predetermined control program, and a transceiver coupled to the microprocessor for communicating information between the microprocessor and other control units in the network.

Abstract: Transmission is controlled using the present method after a handoff procedure has been entered between a subscriber unit and target transceivers. During this process, a communication link between the subscriber and at least one other transceiver is maintained. A quality factor of a signal from the subscriber is received by the target transceiver. If the quality factor meets a quality threshold, then a transmission from the target transceiver is activated. If the target transceiver is active and the quality factor drops below the quality threshold, then the transmission from the target transceiver is terminated.

Abstract: A method of selecting sector antenna which is capable of reducing interference and improving the efficiency of utilization of frequencies is applied to a mobile radio communication system wherein a plurality of sector antennas whose half-power beam widths are different from basically used normal sector antennas are used so as to cover the same areas in an overlapping state. A radio base station located within a corresponding zone covers a plurality of sector cells using the sector antennas provided for each of the corresponding sector cells. Further, some of the radio base stations employ a way to cover partial area overlapping a normal sector cell with a narrow sector cell using a sector antenna whose half-power beam width is small. Each radio base station has a predetermined constant according to the half-power beam width.

Abstract: Through utilization of a transportable earth station capable of communicating with both of a mobile satellite communication system and a terrestrial based mobile communication system and a portable terminal which is capable of radio communication with the transportable earth station and used in the terrestrial based mobile communication system, it is possible to communicate with both of the terrestrial based mobile communication system and the mobile satellite communication system by only one portable terminal in a wide variety of communication environments.

Abstract: Method and system for locating nomadic users in a personal communication services (PCS) system by utilizing two strategies for locating such users and a per-user criterion for determining which, if any, of the two strategies should be used. The method and system augment basic two-level strategies for locating users specified in IS-41 and GSM standards of PCS systems. One strategy utilizes forwarding pointers and the other strategy utilizes per-user location caching. One per-user criterion is a call-to-mobility ratio (CMR) which is the ratio of the average rate at which a user receives calls to the average rate at which the user moves. A variation of this criterion is the local CMR (LCMR) which is the ratio of the average rate at which a user receives calls from a given registration area, to the average rate at which the user moves. The method and system reduce the average time and overhead required to locate and deliver information to such nomadic users.

Abstract: A cellular telecommunication system comprised of low-Earth orbiting satellites featuring allocation of communication channels among users in cells is disclosed. Each subscriber unit is programmed with an embedded class identifier. During periods when it is desirable to limit acquisition of a satellite to some restricted class or set of classes, such as periods of heavy use, the satellite broadcasts a list of inhibited class identifiers allowing only uninhibited classes access to the communication system. The method reduces thrashing by allowing access to users on a hierarchy class basis. The method uses both real time cell loading data and historical cell loading information based on previous experiences and can be programmed to limit access to emergency services in the case of natural disasters.

Abstract: In a radio communication system, in particular a mobile communication system, variable-rate information flows originating from different sources (CV1, CS1; CV2, CS2) and relative to a same communication are transmitted on a same radio channel. Each mobile station (M1 . . . Mh) and the fixed part (B1 . . . Bn; RNC) of the system comprise a unit for the control of the variable-rate transmission, which dynamically allocates the available bits to the different streams by taking into account the needs of the sources (CV1, CS1; CV2, CS2), the conditions of the channel (6) and the system occupancy. (FIG. 1).

Abstract: A method is provided of topographically displaying selected information of a plurality of cells within a cellular communication system through a display device. The method includes the steps of accessing the selected information from an information database and correlating the selected information to respective cells of the plurality of cells. The method further includes the step of creating a topographical display of the plurality of cells of the cellular system through the use of representative polygons, with each polygon representing a service coverage area of a cell of the plurality of cells and displaying the selected information as visually variable values within the representative polygons of the topographical display.

Abstract: Radio zones 2a through 2d are each assigned radio frequency channels of the number corresponding to the zone traffic, one frequency f1 of the radio frequency channel is assigned in common to all radio zones, and radio channels of the same frequency are assigned spectrum spreading codes different for each zone. A mobile station is provided with two correlators 14 and 15. If the received signal level lowers when the mobile station stays in the radio zone 2a and is in conversation over the channel of a frequency f2, the mobile station once switches the communication to a channel of the common frequency f1 and continues the communication using one of the correlators, while at the same time the mobile station scans spectrum spreading codes for control channels of the respective radio zones by the other correlator for measuring the received signal levels of the control channels and determines a destination radio zone which provides the maximum received signal level.

Abstract: The invention relates to a method for controlling base station transmitters in a cellular system, such as a GSM system, the base station comprising at least two transmitters (TX1 . . . TX4) transmitting on at least one control carrier and at least one traffic carrier, wherein the power transmitted on the traffic carrier is on the average lower than the power transmitted on the control carrier. In order to improve the overall life expectancy of the transmitters, at least the transmitter transmitting on the control carrier is changed constantly. (FIG.

Abstract: A method of invoking and canceling voice and data service between a mobile unit and a base station. Using a standard telephone system, the connection for a voice service and a data service is the same. With the introduction of the digital wireless link, the voice connection and the data connection are different. Therefore new dialing commands which indicate the intent of the connection are created. These commands can also be used to designate the intent of the call from a mobile unit capable of data and voice service but not capable of simultaneous voice and data service. They can also be used to invoke simultaneous voice and data services.

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 monitoring computer (115) monitors a communication resource within a wireless communication system for transmissions by communication units. Upon detecting transmissions, which contains a communication unit personality code, the monitoring computer compares transmission time and location information, stored in a database (117), for the communication unit to determine if multiple communication units are using the same communication unit personality code. If multiple communication units are detected, the monitoring computer reprograms at least a portion of service access information of the communication units. In this manner, discrepancies in communication unit programming may be detected and corrected.

Abstract: An N=3 frequency plan for 60 degree sector transmit sector receive (STSR) cell sites is based upon dividing available channels into 18 frequency groups. Frequency assignment is in accordance with an odd-even cyclic distribution of channels which provides a three-channel separation between sectors within a cell and at least seven-channel separation between adjacent cells. This ensures adequate channel isolation between sectors and improved adjacent channel C/I performance throughout the network. The N=3 frequency plan increases channel capacity by approximately 38% in AMPS and 114% in TDMA-3.

Abstract: Communication units are provided access to a communication system (100) in the following manner. A base station (202) receives, from a requesting communication unit, a request, via a shared inbound communication resource (209), for an available message path (207). When a dual-mode outbound communication resource is operating in a control mode (205), the message path (207), having a first inbound communication resource (204) and the dual-mode outbound communication resource operating in a partial control mode (206), is assigned to the requesting communication unit. Thus, the shared inbound communication resource is consistently available, providing access to the communication system.

Abstract: A method for establishing a logical connection between a plurality of sites (101-110) and either a plurality of site controllers (112-115) or a switching center (117) in a radio communication system (100) may be accomplished in the following manner. A first site (101) is selected from a first pair of sites (101,104), wherein the geographical separation (119) between the first pair of sites (101, 104) exceeds the geographical separation between any other pair of sites. Upon selecting the first site (101 ), at least a second site (106, 108) is selected to form a group of selected sites (101,106-108). The group of selected sites (101,106-108) is assigned to a first site controller (112), or a first control portion (201) of the switching center (117), such that communication resources provided by the group of selected sites (101,106-108) can be accommodated by the assigned controller (112), or control portion (201).

Abstract: In a microcellular system operated in the same frequency band as a cellular system, an interference-free channel is automatically searched and allocated. The microcellular system which shares the frequency band with the cellular system comprises a control unit, a base station and a multi-channel selecting receiver. The multi-channel selecting receiver monitors a use status of cellular channels of the band to detect idling channels and allocates them to its own system. Whenever a communication request is issued, the base station detects a channel not used by its own system from the idling channels and allocates it for communication.

Abstract: A cordless telephone set includes a battery, and a communications part for communicating with another cordless telephone set via a transmission medium including radio channels, the communications part comprising a part which detects a call received via the transmission medium and indicates receipt of the call. A D.C. signal detection unit detects a D.C. signal supplied from a battery charger when a battery is coupled to the battery charger and charged thereby. A power supply line setting unit, which is coupled to the part of the communications part and the D.C. signal detection unit, establishes a power supply line for supplying electricity generated by the battery charger to the part of the communications part when the D.C. signal detection unit detects the D.C. signal.

Abstract: A private branch radio extension terminating system includes radio base station units, at least one line control unit, and a central processing unit. The radio base station units are installed in a plurality of places each capable of accommodating a plurality of private branch radio extension terminals within its radio wave range. The line control unit controls the radio base station units. The private electronic branch exchange includes a time-division switch for accommodating the line control unit, a central processing unit for controlling the private branch radio extension terminals via the line control unit and the base station units, and a storage unit for storing various data and programs.

Abstract: A highly fault tolerant method of radio communication of information in the form of a message packet employs a distributed network of transmitter/receivers `transceivers` each having a unique identification ("ID") number. An initiating transceiver creates a message packet having the ID of a transceiver intended to receive the message packet. It then broadcasts the message packet to transceivers within its transmission range. Each transceiver which receives the message packet checks to see if there are errors and sends an acknowledgement if no errors. The transceivers determine valid message packets by determining if the message has not expired, if it has not been seen before and there were no errors in the received message packet. The transceiver also determines if the transceiver ID in the message packet match its own transceiver ID, and if it does, is the message has been successfully transmitted to its intended transceiver.

Abstract: A highly fault tolerant method of radio communication piggybacked upon time division multiple access (TDMA) digital cellular radio telephone systems transmits message packet through a distributed network of transmitter/receivers, (tranceivers) mobile units, each having a unique identification (ID) number. An initiating mobile unit creates a message packet having the ID of a mobile unit intended to receive the message packet. It then broadcasts the message packet in a non-interfering fashion to local mobile units within its transmission range, at a time period which does not overlap a time slot in which it communicates with a cellular base unit. Each mobile unit which receives the message packet checks to see if there are errors and sends an acknowledgement if no errors. The mobile units determine valid message packets by determining if the message has not expired, if it has not been seen before and there were no errors in the received message packet.

Abstract: A highly fault tolerant system for datagram communication of information in the form of a message packet employs a distributed network of transmitter/receivers `transceivers`, which interact with `bridge transceivers` which are transceivers connected to a wired network, and wired nodes each having a unique identification ("ID") number. An initiating unit, which may be a transceiver, bridge transceiver or wired node, creates a message packet having an ID of an intended destination unit. If initiated from a transceiver, the message packet finds its way to a wired network by broadcasting the message packet to local transceivers. The transceivers determine valid message packets which have not expired, not been received before and were transmitted without errors. If the message packet is valid and the transceiver ID does not match its internal ID, the transceiver broadcasts the valid message packet to other local transceivers. The transceivers which receive the message packet repeat the process.

Abstract: In a two-way interactive communication video network having a network switching center for point-to-point communications between subscribers at different geographic locations, a local base station configuration is provided for facilitating low power battery operated portable subscriber units. The local subscriber units surrounding a base station are adapted for multiplex transmission of digital messages synchronously related to a broadcast television signal for system coordination. Digital messages are transmitted from the local subscriber units to the base station data processing facility through a set of receive only cell site subdivision zones distributed over the base station transmitter geographical range, which communicate with the base station data processing facility over a communication link such as wired cable. Messages are compiled and relayed by satellite to a network switching center transmitter site for nationwide point-to-point communications.

Abstract: In a cellular network, a multiple-access methodology and concomitant circuitry in which TDMA is used inside each cell and CDMA signals, having pulse shapes with low cross-correlations, are assigned to adjacent cells. For example, these pulses could be Direct-Sequence Spread-Spectrum pulses. Such a hybrid system combines the high intra-cell capacity of TDMA with the inter-cell and multipath interference rejection capabilities of CDMA.

Abstract: A cellular terminal for transmitting information defining its location upon placing a 911 call. The cellular terminal includes a global satellite positioning (GPS) device; and upon the user of the cellular terminal placing an emergency telephone call, the cellular terminal interrogates the GPS device to obtain the geo-coordinates. The cellular terminal then transmits the geo-coordinates to a cellular telecommunication switching system. The cellular switching system or a public safety answering point (PSAP) system responding to the 911 call converts the geo-coordinates into location information. In addition, the cellular terminal transmits to the cellular telecommunication switching system pre-defined vehicle description information if the cellular terminal is being utilized within a vehicle. If the cellular terminal is a hand held unit, the cellular terminal can be programmed to transmit personal characteristics of the person using the cellular terminal.

Abstract: A method for updating subscriber data in a cellular radio system, and a corresponding cellular radio system, in which method a visitor location register (VLR) receives from a home location register (HLR) of the cellular radio system a restart indication (HLR Reset); and changes the restart number (HLR Reset Num) of the home location register which sent the restart indication in the home location register list of the visitor location register; when the visitor location register (VLR) receives from a mobile exchange (MSC) an indication of the establishment of a radio connection with a subscriber (MS), the visitor location register (VLR) compares the subscriber-specific restart number of the subscriber (MS) with the home location register restart number (HLR Reset Num) of the subscriber (MS), and updates the location data of the subscriber on the basis of the comparison.

Abstract: A mobile phone includes a modem, hereinafter referred to as a cellular radio modem. This cellular radio modem supports two modes of operation--an analog mode, where the cellular radio modem provides an analog signal for transmission; and a digital mode, where the cellular radio modem provides a digital bit stream for transmission. During operation, i.e., the existence of a data connection to a far-end modem, the cellular radio modem is alerted by the cellular network to switch to the appropriate mode--analog or digital. The cellular radio modem then switches and continues transmission in the new mode. In this embodiment, the far-end modem is part of a modem-pool located within the Mobile Telecommunications Switching Office of the cellular network. The far-end modem automatically detects this switch by the cellular radio modem and itself switches to the appropriate mode.

Abstract: A cellular telephone is interconnected to a control unit via a cable. The cable contains both appropriate interdisciplinary connections for attachment to the telephone at one end and to the control unit at the other end via a universal connector. At least one contact of the universal connector is capable of producing a signal coded to identify the type of cellular telephone attached to the connector at the other end. A decoder at the control unit identifies the type of phone as by table look-up and establishes appropriate interfacing operational functions at its universal connector to properly operate with the telephone. Accordingly, the control unit can function with any of a wide variety of cellular telephones having differently configured cable connections and cable connector disciplines of contact assignments.

Abstract: A private network system including mobile radio telephones is able to originate connection and terminate connection even when any of the mobile radio telephones are moved from one exchange where the position of the mobile radio telephone is registered to another exchange. In the private network system which comprises a plurality of exchanges for switching telephones, each of the exchanges includes one or more radio connection controllers for radio communicating with mobile radio telephones, and a plurality of mobile radio telephones connected through the radio connection controller to the exchange for switching, the radio connection controller has an area in which the controller can communicate with the mobile radio telephones.

Abstract: A microcellular digital packet communication system is provided for digital communication having a plurality of repeating packet-mode fixed-site transceivers each being at a plurality of different sites and each being capable of communicating on mutually-common frequencies, including for example by means of frequency-hopping spread spectrum, wherein a terminal transceiver directly communicates substantially simultaneously with at least a few of the fixed-site transceivers on the mutually-common frequencies and distributes information packets of a single originating message among the fixed-site transceivers, the fixed-site transceivers forwarding the information packets via multiple communication links to a single destination terminal on the mutually-common frequencies at which the message is reassembled. The system enables reliable handoffs and robust connectivity by maintaining multiple simultaneous communication links between terminal transceivers and repeating transceivers.