Abstract: A repeater system in a communication system including a base station and a mobile unit provides a communications link between the base station and the mobile unit when the mobile unit is located in an environment that is substantially closed off to high radio frequency communication between the base station and the mobile unit. The repeater system has a first linear two-way frequency converter including a high frequency port for two-way coupling to the base station and a low frequency port for two-way coupling to a low frequency signal that is capable of distributing radio frequency power through the closed environment. The low frequency port is connected to a cable which propagates and receives low radio frequency power within the closed environment.

Abstract: A method for routing enhanced 9-1-1 (E9-1-1) calls from a mobile emergency user to a Public Safety Answering Point (PSAP). The method is directed specifically for use in a wireless communication system which includes a plurality of base stations each of which is operative to communicate with corresponding mobile units within its coverage area over air interface channels. When all interface channels of the corresponding base stations of the mobile emergency user are busy, the location of the emergency mobile user will determined in cooperation with a Location Adjunct Processor (LAP). All other mobile units communicating with the corresponding base stations will be identified. Predetermined uplink and downlink RF measurements for each of these mobile units will thereafter be extracted and by reference to the same it may be determined which of the mobile units are also within the coverage areas of neighboring base stations.

Abstract: A method and system for providing a reliable means to perform handoff from a code division multiple access (CDMA) system using a pilot signal to an alternative access communication technique system. Simple pilot box circuitry is added to a set of border base stations. The border base stations are base stations which operate only in the alternative access communication technique and which have coverage areas which are contiguous with coverage areas of CDMA operation base stations. The mobile unit monitors for the pilot signal from the border base stations in the same manner as it monitors for pilot signals from the CDMA operation base stations. When the mobile unit detects the pilot signal corresponding to a border base station, it notifies a system controller in accordance with standard operation. The system controller is aware that the pilot signal corresponds to a border base station and thus triggers a hard handoff process to the alternative access communication technique system in response thereto.

Abstract: A method for transferring an active connection between a mobile telephone handset and a first mobile telephone system to a second mobile telephone system, which includes the steps of detecting that signal strength of the active connection has fallen below a predetermined threshold; sending a request to the first mobile telephone system to set up an alternative connection from the first mobile telephone system to the mobile telephone handset through the second mobile telephone system; and transferring the active connection to the alternate connection.

Abstract: A method and apparatus used in the context of a digital cellular communication network for allowing a remote unit to determine the conditions under which a handoff should occur and the procedure to be followed. The method and apparatus of the present invention controls handoffs in a manner which causes the boundaries of a cell within a digital cellular network to remain relatively well defined and to very closely conform to the boundaries of a cell of an advanced mobile phone system with which the cellular digital packet data system is associated. The present invention also reduces the effort required by a remote unit within a cellular digital packet data communication system when attempting to change channels. Primary and Secondary Thresholds are defined in accordance with the present invention.

Abstract: A method and apparatus prioritize communications in a two-way communication system (102, 104) serving portable subscriber units (122) in a coverage area (500). A fixed portion (102) of the two-way communication system (102, 104) requests (904) location information (824, 224, 826) from a subset of the portable subscriber units (122) in response to having a need to communicate therewith, and then receives (906) the location information (824, 224, 826) from the subset of the portable subscriber units (122). The location information (824, 224, 826) includes mobility index values (826) determined by the subset of the portable subscriber units (122) for indicating mobility of each portable subscriber unit (122). The fixed portion (102) then prioritizes (908) the communications based upon the mobility index values (826).

Abstract: A system and method is provided for effecting registration in a system for routing a call to a subscriber to a personal telephone number service in an integrated wired and wireless communication network by utilizing in association with at least one land line terminal located in a public gathering place such as a restaurant an adjunct registration device which cooperates with portable registration devices capable of being identified by such adjunct registration devices. In a manual version an adjunct registration device is situated at the site of the subscriber premise terminal and registration in the ISCP of the advanced intelligent network (AIN) of the wireline system is effected by subscriber actuation of the manual device. In an automated version the registration device at the site of the terminal includes a transceiver for emitting a periodic low power and limited range scanning signal to detect the presence of a smart portable registration device carried by the subscriber.

Abstract: Apparatuses and mobile stations are described which provide packet data services in TDMA (Time Division Multiple Access) cellular systems, based on providing shared packet data channels optimized for packet data. A first "integrated" embodiment utilizes the current cellular infrastructure to the extent possible consistent with functional and performance requirements. Shared packet data channels in base stations may be provided dynamically determined by demand. A packet data controller in each Mobile services Switching Center controls access to the packet data services. A packet data router in each MSC routes packets to and from the MSC service area. A backbone network interconnects packet data routers and Interworking Functions providing internetworking with external network(s).

Abstract: A method, performed by a mobile station (119), prevents an active call from being dropped when the mobile station (119) suddenly transitions from a first coverage area (121) to a second coverage area (122) in a code division multiple access (CDMA) cellular radiotelephone system (100). The active call is determined (601) to be in danger of being dropped responsive to the mobile station (119) suddenly transitioning from the first coverage area (121) to the second coverage area (122). The first base station (115) is notified (602) that the active call is in danger of being dropped responsive to the step of determining (601). The active call with the first base station (115) is determined (603) to be in the process of being dropped responsive to the step of notifying (602). The active call is established (604) with the second base station (116) in the second coverage area (122) before the active call with the first base station (115) is dropped responsive to the step of determining (603).

Abstract: A method of transferring a user message-conveying radiotelephone call by a subscriber unit from a first radio coverage area, served by a first fixed control unit which is coupled to a wireline telephone switch, to a second radio coverage area served by a second fixed control unit, includes transmitting a directory number, associated with the first fixed control unit and the wireline telephone switch, the directory number identifying a wireline telephone number of the first fixed control unit, from the first fixed control unit to the subscriber unit; storing the transmitted directory number at the subscriber unit; transmitting the stored directory number from the subscriber unit to the second fixed control unit when a need for transfer of the radiotelephone call to the second fixed control unit from the first fixed control unit is determined; calling the transmitted directory number from the second fixed control unit; in response to the calling of the directory number, connecting the second fixed control unit

Abstract: A spread spectrum CDMA communications system for communicating data and/or digitized voice between a plurality of users to a plurality of PCN units. The spread spectrum communications system is located within a same geographical region as occupied by an existing FDMA, proposed TDMA or any other mobile cellular system. The spread spectrum CDMA communications system includes a plurality of PCN-base stations and a plurality of PCN units. A PCN-base station has a comb filter for notch filtering predetermined channels of the mobile cellular system, a device for converting the format of the data into a form suitable for communicating over radio waves, a spread spectrum modulator for spread spectrum processing the data, and a transmitter for transmitting the spread spectrum processed converted data from the PCN-base station to a PCN unit. The PCN-base station also has an antenna, and spread spectrum detectors for recovering data communicated from the PCN units.

Abstract: A system of the subject invention includes a mobile telecommunications switching office (MTSO), several base stations and mobile units. The base stations serve respective sectors or cells to establish radio communications with mobile units in their sectors or cells. The base stations are connected to the MTSO which performs switching to establish call connections between mobile units and/or between units served by an external network to which the MTSO is connected. The MTSO uses dynamic channel allocation to designate base stations to serve a call connection in active mode and in standby mode for a particular channel. Therefore, if communication with the base station serving a call connection in active mode is disrupted by a building, terrain or an equipment failure, for example, the MTSO can set the base station currently in active mode to standby mode, and can set the base station currently in standby mode, to active mode to serve the call connection on the channel.

Abstract: A wireless communication system formed of a plurality of antennae, the antennae being arranged in a grid pattern over a communication region, wireless portable terminals located within the communication region for emitting and/or receiving electromagnetic signals via the antennae, apparatus for determining the position of at least one of the terminals within the communication region relative to the grid pattern.

Abstract: The present invention comprises methods and apparatus for providing programming from both satellites (11) and local sources (L) using a single receiving antenna (32). In a preferred embodiment, beams (18) emanating from a geosynchronous satellite (11) are collected using the main lobe (36) of a home receiving antenna (32), while a rebroadcast signal (26) generated by an airplane (20) circling above the home (H) is simultaneously sensed using a side lobe (38) of the receiving antenna (32). The airplane (20) flies along a path (40) which is a closed loop so that it is always positioned in a region where the aircraft antenna (24) can supply signals (26) to the receiving terminal (28) using the side lobe (38). The present invention may be implemented using any form of airborne platform (20), whether it is manned or unmanned. A wide range of methods may be employed to deliberately enhance the sensitivity of the side lobe (38) of the receiving antenna (32).

Abstract: A transmission power control method in a cellular radiotelephone system that includes, within at least one cell site, first and second stations, each having a transmitter and a receiver for a predetermined radio channel, and dynamically adjusts transmission power levels, comprising the steps of forming location groups by dividing radio channels within the cell site around the first station into a plurality of groups which are from lowest group to highest group, measuring, in the first station, levels of signals received from the second station, allotting the second station to a location group corresponding to the measured signal level, assigning an idle traffic channel to the second station by checking traffic channels according to a location group of the second station, determining a normal operation state in case of being within a level range, a power decrease requiring state in case of being over a maximum value of level range, and a power increase requiring state in case of being below a minimum value of

Abstract: A cellular radio network, and methods for updating location and setting up a call in a cellular radio network. The network comprises at least one mobile subsystem, which serves conventional mobile stations. The network knows the location of the subsystem and the mobile stations with an accuracy of a location area. The location data of a mobile station registered in the subsystem is the identification data of the subsystem, which is not updated again until the radio station leaves the subsystem. In the call set-up, a two-stage interrogation is conducted: first, the identifier of the subsystem is obtained as the location data of the mobile station; second, the current location of the subsystem where the call will be routed to is obtained by means of the identifier of the subsystem.

Abstract: A method and system for performing macrodiversity or soft handover in TDMA radiocommunication systems are described. Half rate transmissions are used to provide additional diversity communication channels in systems having insufficient timeslots at full rate. The mobile station can receive the same information from and/or transmit the same information to a plurality of base stations to provide diversity combination and improve transmission quality. The mobile unit assists in making handover decisions by monitoring the signal strength of control channels transmitted by base stations in neighboring cells.

Abstract: An improved method and system for performing a pilot signal searching operation in anticipation of handoff in mobile station communication between base stations is disclosed herein. The searching operation is described herein as being implemented within a cellular communication system which uses code division multiple access (CDMA) modulation techniques. The mobile station maintains a list of an Active Set of pilot signals transmitted from base stations with which the mobile station is to communicate through, and a Neighbor Set of pilots from base stations within a predetermined proximity of the mobile station. In addition to the Neighbor and Active Sets of pilots, the mobile station maintains a list of Candidate and Pre-Candidate Sets of pilots. Based on analysis of the signal strength of the pilot signals received at the mobile station, base station entries from the Neighbor Set may be assigned to the Pre-Candidate and Candidate Sets, and eventually to the Active set.

Abstract: A packetized cellular system in which a mobile quasi-periodically transmits a beacon signal containing an ID number to a first base station in the cell in which it is located for storage with the ID's of other active mobiles in the cell. A copy of a list of the active mobiles in that cell is transmitted to all adjacent cells where they are placed on non-active list. Control of a mobile is handed-off to a second base station upon the receipt of a transmitted ID number of the mobile at the second base station. The mobile is then listed as active in the database of the second base station and non-active in the first base station.

Abstract: A universal wireless radiotelephone communication apparatus is operative in both a first radiotelephone communication system including a first base station having a wide area of coverage, transmitting radiotelephone signals at a first band of frequencies and in a second radiotelephone communication system including a second base station having a localized area of coverage, transmitting radiotelephone signals at a second band of frequencies higher than said first band of frequencies. The second band of frequencies is optimally selected with an offset of less than twice a frequency contained within said first band.

Abstract: A base station and a mobile station in a mobile communication system capable of reducing interference among mobile stations and increasing a subscriber capacity of the system. The base station has a unit for measuring a measurement value for at least one of a receiving level and an interference ratio level of the mobile station transmission signals, and a unit for producing a mobile station transmission power control data specifying a mobile station transmission power required in adjusting the measurement value to a target level according to a number of base stations simultaneously in communication with the mobile station.

Abstract: Handoff methods perform cell-to-cell handoff between cells of the same satellite and between cells of different satellites. Handoff is initiated by an individual subscriber unit (ISU) based on local conditions. Once handoff is needed, the ISU chooses a candidate cell to transfer its communication based on a dynamic handoff candidate list provided by the satellite. After selecting a candidate cell, the ISU requests handoff, the satellite or satellites perform the handoff and communication begins over a new channel in the candidate cell.

Abstract: Call priority is realized in a mobile radio telephone system by ascertaining that a call should be given priority, assigning channels preferentially to a priority call, assigning higher quality channels preferentially to the priority call, and through-connecting the call. Call priority may also be realized by ascertaining that a call should be given priority, assigning channels preferentially to a priority call, allowing a more exhaustive paging for paging a mobile station than would be allowed if the call were not given priority, and through-connecting the call.

Abstract: In order to mitigate problems caused by total or partial failure of a number of sectorised radio channel unit transceivers (RCU) in a base station of a particular cell (16) of a radio communications system, base stations (26, 32) in adjacent cells (14, 20) increase the power transmitted from RCUs controlling sectors adjacent to that particular cell 16, thereby filling the gap in coverage left by the failure of that cell (16).

Abstract: A system and method for establishing and administering personal home areas for subscribers of a cellular telecommunications network. The system enables one or more Home areas to be designated for each subscriber. The Home areas may vary in size, and the system is capable of applying a different set of service parameters inside an area and outside the area. Each Home area is defined by designating the latitude and longitude coordinates, and the altitude of a subscriber's home location, as well as the radius of the Home area from the home location. A system operator may designate one of several alternate radii by entering the coordinates of the center of the area at various levels of precision, each of which corresponds to a different Home area radius.

Abstract: In a mobile radio telecommunications system having a switching unit, a control station connected to the switching unit, a plurality of base stations connected to the switching unit, and a plurality of mobile stations connected to the base stations by radio channels, the base stations are each situated at private property, and each includes a controller for determining a direction in which a mobile stations is moving. The controller receives via the control station and switching unit information representative of the levels at which the individual base stations have received a radio wave from a mobile station, compares the received levels, determines, based on the result of comparison, that one of the base stations having the highest received level currently covers the mobile station, and determines a direction in which the mobile station is moving on the basis of a transition of the highest received level.

Abstract: In order to detect a paging channel assigned to a pager in a shorter time in a frequency divided pager network system, a plurality of paging channels given priorities in channel searching are separately assigned to the paging areas in a manner wherein reuse in adjacent paging areas is avoided. A frequency subset number and frequency subset indicators related thereto, are stored in a memory in a pager. Subsequently, paging channels available in the system are allocated to the frequency subset indicators. Further, a relationship between the frequency subset indicators and the corresponding paging channels is arranged in the form of a table and then stored in the pager. Then, the paging channels are assigned to the paging areas according to the relationship. The above mentioned paging channels given priorities in channel detection are monitored so as to detect which priority channel is transmitted to the pager.

Abstract: The filter of the present invention pre-processes signaling messages transmitted by the base station while the radiotelephone is in the idle mode. The radiotelephone informs the filter of the roam status and idle status and identity of the radiotelephone. The filter then intercepts the incoming signaling messages while the processor is in the sleep mode conserving power. When the filter detects a message requiring further processing by the processor, the filter interrupts the processor to process the message.

Abstract: A system is arranged to a) monitor the flow of data communicated within a session between a mobile end-user device and a host via a connection which includes a wireless link established over a wireless network b) detect a disabled condition of the wireless link c) in response thereof, simulates a functioning mode of the session, and d) when the wireless link is restored, resume the session between the mobile end-user device and the host at the stage where the disabled condition occurred, as if a disconnect never occurred.

Abstract: A mobile communication system and its multiple connection method enabling to perform concise and high quality multiplex communication, in which a mobile exchange station stores identifiers of a plurality of radio base stations and transmits a communication signal directed to a mobile station to all the radio base stations. The mobile exchange station stores the identifier of the radio base station which started the communication with the mobile station within the plurality of radio base stations. When the radio base station has opened a radio line with the mobile station, the radio base station which received the communication signal transmits the communication signal to a radio zone, and when the radio base station does not open the radio line with the mobile station, the radio base station disuses the received communication signal.

Abstract: A manual home location register (M-HLR) for use in a cellular telecommunication system provides manual visitors in a visited network with the same registration capabilities as automatic visitors from networks that have automatic roaming agreements with the visited network. The M-HLR maintains a database of manual visitor information separate from the network's database of home subscribers and automatic visitors. Initial registration in the visited network by a manual visitor is recorded in the M-HLR and enables the manual visitor to roam freely between multiple mobile switching centers (MSCs) in the visited network without having to re-register in each MSC.

Abstract: A radio communication apparatus of this invention includes a mode designation switch for selectively designating and inputting a desired mode from an analog mode and a digital mode, and a mode storage circuit for storing the desired mode designated and input by the mode designation switch and has a mode setting control function, a mode comparison function, and a mode change control function. In order to establish a radio link, control is performed to set a mode for transmitting a communication signal in accordance with the desired mode stored in the mode storage circuit. After the start of transmission of the communication signal, the mode comparison function compares the mode set by the mode setting control function with the desired mode stored in the mode storage circuit.

Abstract: A method is disclosed of reducing data loss during cellular handoff of a mobile among base sites by detecting an end-of-line signal by a fax adapter (13a or 106a) from the transmitting fax, buffering (13b or 106b) subsequent fax information, and transmitting filler bits in place of the EOL and buffered information.

Abstract: The airborne communication system enables one or more radiotelephones to communicate with a ground based cellular radiotelephone system. In the preferred embodiment, the aircraft is equipped with a repeater that relays a signal from the airborne radiotelephone to the ground base station and vice versa. Alternate embodiments use an airborne base station to register the radiotelephones before registering them with the ground system. Alternately, the antennas on the ground could be used to form aerial cell sites by pointing the antennas upward to where the aircraft flies through the cells. The system of the present invention provides the additional benefit of enabling the ground based cellular radio systems to source a call to the aircraft radiotelephone.

Abstract: A method of providing communication services in a cellular communication system which consists of a plurality of service coverage areas having a plurality of shared frequency microcells. Each microcell has an omnidirectional, remote antenna interconnected with a base site. The method consists of receiving a request, at the base site, to provide communication access to a communication unit. A supervisory audio tone is simulcast through each omnidirectional, remote antenna of the plurality of shared frequency microcells. A signal quality factor of a looped-back supervisory audio tone received from the communication unit at each omnidirectional, remote antenna is then measured. A communication link between the communication unit and base site is then established through a selected antenna of said plurality of omnidirectional, remote antennas. The antenna is selected based upon the signal quality factor of the looped-back supervisory audio tone.

Abstract: An earth station transceiver (210) is provided for communicating with at least one satellite (110, 120) in orbit. The earth station transceiver (210) has an antenna with an array of antenna elements (220, 230) and steering circuitry (240) for steering an antenna pattern created by the array of antenna elements. A position of a beam (310-330) from a satellite can be represented by a beam number. The antenna pattern can be determined without taking signal quality measurements when the beam is at an extreme elevation angle as represented by the beam number. Signal quality measurements can alternatively be made during a time slot or frame to choose an antenna pattern instead of choosing an antenna pattern based on satellite beam number when the beam is not at an extreme elevation angle. Signal quality measurements using the same antenna pattern are made to perform an intra-site handoff. Signal quality measurements using all antenna patterns are made to perform an intersite handoff.

Abstract: A mechanism for handing off between an overlay cell (48) and an underlay cell (50). The underlay cell (50) is smaller than and has a common area with the overlay cell. A threshold level (RSSI-THP) is established which corresponds to the sum of a nominal threshold level (RSSI-U) and a value obtained by subtracting the current attenuation level (MT) from the minimum attenuation level permitted by the underlay cell (MU). If the RF signal level of the serving cell (RSSI-SRV) is greater than the established threshold level (RSSI-THP), the mobile unit is handed off to the underlay cell (50), if not already in that cell; and handed off to the overlay cell (48) if equal to or less than the established threshold level (RSSI-THP), if not already in that cell.

Abstract: Aircraft communications are established on a cellular system by having the transmission to aircraft directed above ground level so as not to interfere with ground cellular systems and having the transmissions from the aircraft at extreme low power levels so as not to interfere with transmissions from ground vehicles. The location of mobile stations either aircraft or ground vehicles for one embodiment is determined by Loran reception or other radio navigation system in the mobile station and transmitted to a mobile switching center to be used in transferring control from cell to cell by use of the determined location of the mobile station. For another embodiment the antennae for aircraft (both base station and mobile) are horizontally oriented while ground vehicle antennae (both base station and mobile) are vertical as in present commercial practice.

Abstract: A method of performing handover of a call associated with a mobile station in one cell but moving towards another cell includes making a first attempt, using for example a MUX1 SNIFF procedure, on the channel allocated to the mobile station for that call. If that attempt fails, the mobile station is allocated a different channel in the one cell and makes a second attempt. This different channel allocation (intracell handover) is performed even if there are no better signal characteristics achieved as a result. This procedure makes it more likely to be possible to achieve handover when a second mobile station associated with an adjacent cell and operating on the same channel as the first mobile station is also within range of the base station of the other cell.

Abstract: A method and apparatus for determining with high resolution the fidelity of communications over a communications channel is disclosed. Portable/mobile radios freely roaming between multiple trunked RF communications sites calculate the fidelity of communications received over current and alternate channels with comprehensive, high bit error resolution using a weighted average error dispersion procedure. The weighted average error dispersion analysis generates for each group of redundant messages (and in some instances subpreamble bits) received by a roaming radio in each message frame a weighted average error dispersion number whose incrementally increasing magnitude reflects deteriorating signal fidelity. Decisions about switching to alternate communications channels are made by the roaming radio based on the incrementally changing weighted error dispersion number so that communication channels may be selected to achieve optimum signal fidelity and continuity of communication.

Abstract: The present invention provides a method of handing off a communication unit in a cellular communication system. The method includes communicating initialization frame data from a target cell transceiver to a base site transcoder; establishing communication between the target cell transceiver and the communication unit; terminating transmission of initialization frame data; communicating ordinary frame data received by the target cell transceiver from the communication unit to the base site transcoder; and handing off the communication unit to the target cell transceiver upon detecting a transition from initialization frame data to ordinary frame data at the base site transcoder.

Abstract: A cellular communication system projects multiple cells throughout a user area. Subscriber units (24) encounter multiple cells as they roam through the user area or as the cells migrate past the subscriber unit (24). When a subscriber unit (24) encounters the fringe area of a cell it must select and transition to a target cell to maintain contact with the system. The subscriber unit (24) performs an analysis of the location, proximity, and expected duration of exposure of candidate target cells using location data transmitted by control channels located in the candidate cells. The subscriber unit (24) then selects a target cell based on these factors.

Abstract: A cellular communication system projects multiple cells throughout a user area. Subscriber units (24) encounter multiple cells as they roam through the user area or as the cells migrate past the subscriber unit (24). When a subscriber unit (24) encounters the fringe area of a cell it maintains contact with the system by selecting and transitioning to a target cell. The subscriber unit (24) performs an analysis using Doppler data of the location, proximity, and expected duration of exposure to candidate target cells. The subscriber unit (24) selects a target cell based on these factors.

Abstract: The power of a first signal is measured and is compared with a threshold. If the first signal power meets a handoff threshold, the system enters the handoff procedure. Once in the handoff procedure, estimates of a first signal quality a signal would have, if transmitted from the first site to the subscriber, and a second signal quality a signal would have, if transmitted from the second site to the subscriber, are determined. If the estimated first signal quality meets a transmit threshold, the first will activate a traffic signal to the subscriber. If the estimated first or second signal quality fails to meet the transmit threshold, the first or second, respectively, will terminate its traffic signal to the subscriber, but the transmission resources will remain dedicated to the subscriber. If the estimated first or second signal quality fails to meet the handoff threshold, the first or second, respectively, will discontinue serving the subscriber.

Abstract: A method and apparatus for matching the location of the forward link handoff boundary to the reverse link handoff boundary. A system constant is chosen which defines the product of the received power and the transmitted pilot power at every base station. The reverse link power level is measured at the base station and the forward link power level is compensated for the reverse link loading to maintain the constant product. Thereby the forward link handoff boundary to the reverse link handoff boundary are aligned to the same location.

Abstract: A cellular telephone system includes a plurality of cell sites and a mobile telephone switching office. Call management, including selection of a cell site most appropriate for a call associated with a mobile unit, are made based on the geographic location of the mobile unit as opposed to the strength of the signal associated with the call. The geographic location of the mobile unit is precisely determined using a NAVSTAR global positioning system, or its equivalent. Each mobile unit includes a GPS receiver that receives information from a geostationary satellite to determine the precise location of the mobile unit. This position information is relayed to the cell site initially managing the mobile unit, and the mobile unit is handed off to a cell site that is most appropriate for the call. Initial selection of an entrance cell site is made based on signal strength, but further call management decisions are made based on location of the mobile unit.

Abstract: A method of setting up and handing off calls in a mobile cellular radio system in which consideration is given to the load capacity of several types of channels. The communication system determines the available capacity of the different groups of channels in the communication system whenever a new call needs to be set up. The system then assigns the new call to the group of channels with the most available channels if the requesting mobile station is a multi-mode mobile station, or the system hands off a multi-mode mobile station from a first group of channels to a second group of channels or vice versa to create free channels for calls from single mode mobiles.

Abstract: A cell extender for use in digital cellular telephone systems comprises a control module, and scanning module, and several traffic modules. The control module bidirectionally repeats the donor cell site control channels. Voice modules therein bidirectionally repeat selected donor traffic channels for mobiles. The voice module amplifies and translates the Reverse Digital Traffic Channel RDTC (transmitted by the mobile). The voice module reframes the Forward Digital Traffic Channel, and advances its timing such that RDTC signals transmitted by the mobile and repeated by the cell extender arrive at the donor with the correct timing alignment. The timing advance compensates for RF path propagation delay between the donor and the cell extender, and for any additional delay through the cell extender. If the voice module determines that the mobile is leaving the cell extender coverage area, it sends a hand-off message returning the mobile to the assigned donor traffic channel.

Abstract: A digital radiocommunication system and method for providing a consistency check to confirm the identity of a candidate cell for handoff of a digital traffic channel are described. Using relative pathloss comparisons reliance on absolute measurements which can lead to inappropriate handoffs for a variety of reasons. Statistical measurements can also be used to further reduce errors.

Abstract: A method for handover in a cellular system is provided which includes periodically scanning from neighboring cells, traffic channels of a serving cell to determine channel metrics. If the channel metrics exceed a threshold, validating the serving cell identity by verifying traffic channel color code. The channel metrics are then periodically transferred to the serving cell where a handover decision is made.