Abstract: A selective call receiver (102) for use in a communication system (100) includes a receiver (404), a memory (412), and a processor (408). The receiver (404) is capable of receiving a message code (314) during a first frame from a first transmitter and the same message code (314) during a second frame from a second transmitter. The memory (412) stores a first and a second canned message, wherein the first canned message corresponds to the message code (314) being received in the first frame and the second canned message corresponds to the same message code (314) being received in the second frame. The processor (408) is responsive to the message code (314) for identifying the first canned message in the memory (412) corresponding to the message code (314) and the first frame, and identifying the second canned message in memory (412) corresponding to the same message code (314) and the second frame.

Abstract: A transmitter-receiver includes a transmitting circuit for providing an output by converting the frequency of a transmission signal input thereto, a receiving circuit for providing an output by converting the frequency of a received signal input thereto, and a local oscillator which generates an oscillation signal having a local oscillating frequency based on a reference signal. A local oscillator signal splitter is connected to the local oscillator and splits the oscillation signal into substantially similar transmit and receive oscillation signals each at the local oscillating frequency. The local oscillator signal splitter supplies the transmit oscillation signal to the transmitting circuit and supplies the receive oscillation signal to the receiving circuit. The transmitting circuit converts the frequency of the transmission signal in accordance with said transmit oscillation signal, and the receiving circuit converts the frequency of the received signal in accordance with the receive oscillation signal.

Abstract: The present invention relates to the reuse of a control channel in a distributed cellular radio communication system. At least one physical channel, the so called physical control channel, in the radio communication system is used for transferring logical control channels. According to the present invention the physical uplink control channel can be reused with respect to logical control channels comprising an access request. The physical downlink control channel can be reused with respect to logical control channels comprising a message that access is granted to a mobile station or a message that someone requests contact with a mobile station. According to the invention the physical uplink control channel and/or the physical downlink control channel is reused. This means that more connections per time unit may be established in the radio communication system.

Abstract: A technique is used in a simulcast radio communication system (200) for providing improved local time information. The technique includes, in a fixed portion (300) of the simulcast radio communication system (200), alternatively transmitting in a radio signal a first local time and a second local time in a predetermined protocol position that occurs periodically in a signaling protocol, wherein the first local time and second local time differ by a time zone interval. A radio (500) that receives the radio signal presents local time to a user in manner that indicates the first and second local times.

Abstract: A communications network simultaneously transmits a single message to a number of recipients. This is called a "multicast" transmission. The communications network should have a recipient list database (1302) to receive a list of recipient addresses, a message database (1304) to receive and store the message, and a message delivery system (1306) to send the message to a number of recipients. The communications network may be adapted to collect acknowledgements or responses to a multicast message. If so, the communications network should have a calling record (1308) for storing message delivery information, a response record (1310) for receiving and storing recipient response information, a response processor (1312) for processing the response information, and a response delivery system (1314) for delivering the processed response.

Abstract: A selective messaging system controller (105) and analogous methods arranged to schedule messages and control transmitters in a messaging system (100) having a service area so as to enhance a reuse factor, includes: a network port (102) for accepting message requests that is coupled to a processor (131) for forming a first plurality of messages, including an associated zone ID (407) for each message, scheduled for concurrent transmission, during a first time period, within a first coverage pattern (503) that creates interference areas (525) and a second plurality of messages scheduled for concurrent transmission, during a second time period, within a second coverage pattern (505) that provides coverage for a portion of the interference areas; the processor further coupled to a transmitter port (106), for sending the pluralities of messages to the transmitters and controlling these transmitters; and a receiver port (109) for receiving a registration message including one coverage zone ID that identifies a cove

Abstract: A base station (214) synchronizes a data stream of a second transmitter (202) with that of a first transmitter while maintaining full user traffic through a radio communication system (200). The first and second transmitters transmit (501), during a first time interval, a first portion of the user traffic in a simulcast mode; and at least the first transmitter transmits (503), during a second time interval, a second portion of the user traffic in a non-simulcast mode. A receiver (204) proximate the second transmitter monitors (505) the second portion of the user traffic transmitted from the first transmitter to determine a time delay, and then adjusts (507) a launch time of the second transmitter in accordance with the time delay.

Abstract: A controller (112) controls (706) at least two transmitters (302) to transmit at least two simulcast signals (502, 504) during a time period. The at least two simulcast signals produce intersymbol interference at a receiver. At least one of the transmitters changes (708) its output amplitude during a portion of the time period, thereby altering the intersymbol interference during the portion of the time period.

Abstract: A circuit (350) for detecting simulcast channel conditions includes a symbol center averaging circuit (308) for providing a center count of excursions above and below at least a first predetermined threshold and for providing a moving average of the center count over a predetermined number of symbol periods and a symbol edge averaging circuit (310) for providing an edge count of excursions above and below at least a second predetermined threshold and for providing a moving average of the edge count over a predetermined number of symbol periods. Finally, the circuit further includes a comparison circuit (360) programmed to receive and compare the moving average of the center count and the moving average of the edge count to provide a control signal (380) for simulcast detection.

Abstract: The present link delay calculation system using a common reference signal and a pulsed or gated tone signal to determine the link delay. The system using a discrete-time Fourier transform to measure phase information and obtain the link delay time. One such system employing a global positioning satellite signal to synchronize signal generation at a control site and demodulation at a remote site.

Abstract: In a messaging system having a plurality of simulcasting base transmitters (104), a plurality of pseudorandom sequence generators (216) are provided (402) for the plurality of base transmitters. The plurality of pseudorandom sequence generators are arranged (403) to ensure that they generate a plurality of pseudorandom sequences having sub-sequences that are different from one another during concurrent transmissions by the plurality of base transmitters. A cancellation-affecting parameter of the plurality of base transmitters is adjusted (404, 406, 408) in accordance with the plurality of pseudorandom sequences during the simulcast transmission from the plurality of base transmitters to limit intervals of carrier cancellation.

Abstract: An apparatus (109) for and method of voting provides efficient use of communication resources (111, 112), while avoiding interference caused by other signal sources, particularly in a simulcast system. Although the same communication resource (111) is used for transmission on multiple base stations or repeaters (103, 105, 107, 113) at the same time in a simulcast system, the present invention provides way to achieve increased signal throughput without causing interference (213, 301) with desired signals (215, 211).

Abstract: A distributed antenna network for reducing multicast interference between multicast cells. More particularly, a system and method are provided for calculating multicast interference zones between the multicast cells and configuring coverage areas to encompass the multicast interference zones. This multicast cell configuration avoids the need for delay time adjusting techniques for equalizing the transmission paths and reduces multicast interference by effectively shifting the multicast interference zones.

Abstract: A new simulcast dynamic delay adjustment capability for a radio frequency (RF) simulcasting repeater system continually, dynamically adjusts the amount of delay applied to a T1 data stream to ensure common synchronization at multiple simulcast transmitter sites. A Global Positioning System (GPS) distributed time standard provides timing references at a control point and at each transmit site. The control point sends a version of its GPS timing reference signal to each transmit site over links also used to carry signals for transmission over-the-air. The transmit sites compare the arrival time of the land line-distributed reference signal with the output of a version of the same signal produced by a local GPS signal. The result of the comparison is used to adjust an amount of additional delay introduced to equalize delays for different transmission site links.

Abstract: Within a desired service area, multiple transmitters at separately located sites simultaneously broadcast the same multi-channel, multi-program signal. Broadcast waves from the transmitters propagate substantially throughout the service area and overlap in a substantial portion of the area. The signals are broadcast as spread spectrum signals and the receivers include despreaders with rake capabilities to obtain enhanced output signals with multi-path reception. In the preferred implementation, the channels are 6 MHz wide channels broadcast in the super high frequency microwave portion of the spectrum. Each such channel carries a multiplexed digital data stream containing packets of information for a plurality of programs, e.g., television programs.

Abstract: Subscriber units (14) can roam from zone (A) to zone (B) and accurately compile fragments of a message that includes fragments transmitted from both zones. Preferably, a subscriber unit (14) assigns different markers to fragments received from different zones. When the subscriber unit senses that a received message includes fragments from different zones, it correlates a number of characters of a fragment received from one zone (A) to a similar number of characters in a fragment received from a different zone (B). If a complete match is not found, the fragments are combined as part of a message. If a match is found, a further comparison looks for additional matches between fragments and, finding such additional matches, erases one copy of duplicate characters.

Abstract: A simulcasting transmitter control apparatus in a base station of a mobile telecommunication system controls the output timing of transmitters so as to achieve a simulcasting of their outputs in the same channel. The control apparatus including: a unit for inputting control data form a base station control unit, a unit for generating a reference clock, a unit for generating delayed clocks divided from the reference clock, and a delay unit for receiving the control data, setting each delay time period in accordance with the control data, and delaying outputting of paging data from the transmitter by the delay time period in synchronization with the delayed clocks. The delay time period of the delay unit according to the respective control data compensates for the delay characteristic of the transmitters. The simulcasting of the radio frequency signals of the same channel in a reiteration cell area is carried out in the present invention.

Abstract: A pager protocol that permits individual pagers to operate in an inactive mode when not being addressed to save power but nonetheless also accommodates high capacity transmission schemes that require non-continuous illumination of sectors occupied by individual pagers. Capabilities of a conventional omnidirectional paging protocol such as one of the FLEX.TM. family may be exploited to facilitate operation in the context of non-continous illumination. A pager transmitter transmits a simulcast transmission where all pagers in all sectors receive the same message. This message includes schedule information about future transmissions to individual pagers. Pagers then plan their switching between the active and inactive states in accordance with the schedule which takes into account a timetable for illuminating sectors.

Abstract: For selective call of mobile units operable at different bit rates, a central station announces a launch start instant of each signal frame to a plurality of base stations based on phase coincident clocks used individually in the central and the base stations. Responsive to call requests of the different bit rates, their time sequential order in each signal frame, and a switching instants of switching one of the bit rates to another, the base stations transmit the call radio signals starting simultaneously in phase coincidence at the launch start instant Preferably, the central and the base stations deal with the requests as packets. Any one of the base stations can reduce its transmission power of the call radio signals if a failure is found therein in one of the call requests delivered thereto.

Abstract: A digital base station improves downlink coverage by allocating multicast and non-multicast channels based on the propagation property of an RF link between a mobile unit and a base station. The non-multicast channels are time slots during which information is transmitted from one antenna, and multicast channels are time slots during which information is transmitted from multiple diversity antennas. Transmission timing is offset from the diversity antennas by an amount that corresponds to the multipath propagation properties of the RF link.

Abstract: A transmitter includes a modulator, a power amplifier and a controller to reduce the effects of phase cancellation in a simulcast paging system. The modulator is digitally configurable to modulate according to at least two protocols. The controller configures the modulator for a first protocol and provides to the modulator a signal to be broadcast. The modulator then modulates this signal according to the first protocol and causes the modulator to introduce a random frequency offset within a frequency range predetermined to optimally reduce phase cancellation for the first protocol. When the controller provides a signal to be broadcast according to a second protocol, the controller reconfigures the modulator for the second protocol. In addition the controller causes the modulator to introduce a random frequency offset within a predetermined range to optimally reduce phase cancellation for the second protocol.

Abstract: A communication network, and associated method, permitting wireless communication with a mobile unit in an indoor environment. Transceivers are positioned at spaced-apart locations and are coupled to a centralized, control device. The transceivers include transmitter portions and wideband receiver portions. Uplink signals transmitted by a mobile unit are received by receiver portions of transceivers within the range of the uplink signal. Downlink signals are generated by at least two transmitter portions of at least two transceivers. The control device controls selection of which transmitter portions and which receiver portions of the plurality of transceivers are utilized to effectuate two-way communication with the mobile unit. Control signals can also be transmitted by the transmitter portions of all of the transceivers such that a mobile unit positioned anywhere within the area of the communication network receives the control signals.

Abstract: An automatic adjustment delay technique for a simulcast of a paging system includes: a reference clock supplying unit for supplying a synchronization signal used as a reference clock, a page data transmission board installed within the paging system for receiving the page data and transmitting the page data in synchronism with the reference clock supplied from the reference clock supplying unit, a plurality of transmission lines and transmission facilities installed between respective base stations and the page data transmission board for transmitting the page data to the base stations, and respective transmitters installed within the respective base stations for receiving the page data transmitted via the transmission lines and transmission facilities and for externally transmitting the page data in synchronism with the reference clock generated by the reference clock supplying unit.

Abstract: A method and the corresponding messaging system of selecting a transmitter for directed message delivery set is a messaging system including a plurality of transmitters arranged and constructed to operate in a simulcast or non-simulcast mode, the method including directing a first and a second transmitter to transmit in the simulcast mode, respectively, a first signal including a reference parameter and a first identification signal and a second signal including the reference parameter and a second identification signal, the first identification signal and the second identification signal distinguished from the reference parameter by, respectively, a first and a second predetermined amount, and receiving an acknowledgment signal that includes a indication of the first identification signal relative to the second identification signal or both relative to a threshold as determined at a messaging unit location, the indication corresponding to a preferred transmitter, selected from the first and the second transm

Abstract: A radio communication system (100) synchronizes multiple data streams associated with a network of transmitters (102) while maintaining full user traffic. The transmitters transmit (901) a first portion of the user traffic in a simulcast mode during a first time interval, (104) and transmit (903) a second portion of the user traffic in a non-simulcast mode during a second time interval. A monitor receiver (104) is coupled to the transmitters by radio signals for monitoring (905) the second portion of the user traffic transmitted from selected transmitters to determine transmission delays. A controller (108) is coupled to the monitor receiver for adjusting (907) the data streams to equalize the transmission delays (303).

Abstract: An infrared (IR) communication system is described in which a base unit for a cell can communicate with a plurality of infrared portable devices through distributed infrared receiver/transmitter (RT) modules over a plurality of channels using IR carrier signals. A call processor, referred to as a radio exchange unit, and controlling communication of a cell, communicates with the base unit to place or receive calls with the IR portable devices. The communication occurs in standard communication frames divided into transmission and receiving segments with each segment further divided into slots and with the slots containing digital data, with each communication channel formed by a slot. Each transmission segment to an RT module is immediately followed by a responsive receiving segment.

Abstract: A method of synchronizing carrier frequencies in a mobile radio network having base and mobile stations, in which a synchronization signal is radiated from the base stations, is received by the mobile stations and is used to derive the transmission frequency.A group of sinusoidal oscillations having different frequencies is emitted from each base station as a synchronization signal. The mobile stations each have a matched filter, with which at least one of the transmitted sinusoidal oscillations can be found and detected.The method is insensitive to fading, and permits an extensive normalization of the circuits in the base stations and, in particular, permits a unified evaluation in the mobile stations.

Abstract: A user headset is provided that is operable to contain an audio device (50) and a receiver (52). The receiver (52) is operable to receive both audio information on multiple channels and also data. The data is received in the form of pulse width modulated sync signals. The sync signals are operable to provide a synchronization signal for 3-D liquid crystal lenses (60). The data is encoded within the sync signal through pulse width modulation. The width of the pulse defines various commands. These various commands define the channel over which the audio is to be transmitted. These channels can either be user-defined or they can be a function of the transmitter. The transmitter includes an audio generator (42) for generating audio signals on multiple channels and also a data generator (40). These are modulated onto a broad band optical signal and transmitted via an IR data link.

Abstract: A communication system (100) for dynamically selecting transmitters (115) for message transmission includes the transmitters (115) for sending transmission signals and a portable messaging unit (105) for receiving the transmission signals, calculating signal strengths of the transmission signals, and transmitting a signal indicative of the signal strengths. A controller (110) receives the signal and determines therefrom carrier-to-interference (C/I) values indicative of relative strengths of the transmission signals received by the portable messaging unit (105). Prior to message delivery, the controller (110) determines a selected transmitter (115) for transmitting a message to the portable messaging unit (105). The selected transmitter (115) is associated with a lowest C/I value that is chosen from the C/I values and that exceeds a C/I threshold value.

Abstract: A paging system includes a site control module for storing paging data and activating a plurality of transmitters simultaneously in response to a transmission approval signal to transmit the stored paging data synchronously. The device includes a paging terminal for encoding paging data to transmit and generating a transmission approval signal upon completion of transmitting the paging data; a plurality of site control modules connected to the paging terminal via a private communication line, for storing the paging data in a memory prepared therein and generating the stored paging data upon receiving the transmission approval signal; and a plurality of transmitters for converting the paging data output from the site control modules into a radio paging signal to transmit; whereby the paging data is transmitted simultaneously in synchronism with the transmission approval signal.

Abstract: In a wide band radio frequency (RF) simulcast communications system analog voice signals are distributed in a digitized form over high speed data channels and processed as high speed data. A conventional Ericsson, Inc. EDACS.TM. simulcast communications system is improved by altering the apparatus and manner by which "clear voice" (unencrypted analog voice) is distributed from a control point and "aligned" at multiple transmitter sites for simultaneous RF broadcasting. In the improved arrangement, the EDACS.TM. simulcast system inherent digital data stream alignment process produces the requisite time domain alignment for the digitized "clear voice" signals without the need for costly analog audio alignment procedures and equipment.

Abstract: A wireless communication system (200, 300, 400, 500) mitigates the effects of excess timing delay caused by varying lengths of communication paths. In one general implementation, a transition communication path (206, 323, 329) is used to transfer a time-advanced version of a timing reference signal so that the cumulative time delay at a transition cell (209, 325, 331) is reduced. In another general implementation, the timing reference signal is time-advanced in all communication paths (403-411), and selected communication paths (403-407) include a time delay means (423-427, 503-507) such that the cumulative time delay at an area (421) near a target coverage area (130) is reduced. By reducing the cumulative time delay at the area (421) near the target coverage area (130), a handoff of a communication of a mobile station (128) into the target coverage area (130) can be performed.

Abstract: A communication system and method are provided for equalizing delay of transmission paths in a distributed antenna network. The distributed antenna network includes a plurality of remote antenna units, a central unit or a base station connected to the remote antenna units by transmission media, where each connection between the base station and one of the remote antenna units forms a separate transmission path having an associated delay time, a delay detector for determining the associated delay time of the separate transmission paths for each of the remote antenna units, and a delay compensator for adjusting the associated delay times in response to the delay detectors so that all of the associated delay times are substantially equalized. The system and method allow the delay parameters for the entire network to be set upon installation and then to be periodically updated without physical intervention by an operator.

Abstract: Within a communication system, driving a numerically controlled oscillator with a frequency of a precision frequency oscillator and adjusting the frequency of the numerically controlled oscillator by a calculated number to be equal to that of a frequency signal derived from an external source. The calculated number utilized to adjust the numerically controlled oscillator is then transmitted to each of a number of subunits. Each subunit has another numerically controlled oscillator that is driven by a frequency derived from an internal communication link connecting the subunit to the communication system; and the other numerically controlled oscillator is controlled by the calculated number so that its frequency matches the frequency of the precision oscillator. The frequency of the internal communication link is controlled by the precision oscillator.

Abstract: In a multiple site radio frequency (RF) simuicasting transmission system, voice and digital data distributed via multi-phase modem over "land-line" inter-site communication links from a control point to the RF transmitter sites exhibit random time delay skew because the modems at each site recover clock signals from an arbitrary one of multiple phases. Reference "tones" for data alignment, consisting of a high frequency clocking signal and a low frequency "gating" signal, are generated at each site synchronized to a GPS broadcast reference signal. Similar tones are also provided to transmitter sites along with the distributed data via the land-line inter-site communication links as a backup. The pair of "backup" reference tones supplied via land-line are automatically aligned at each site to the GPS receiver generated reference tones by individual phase comparison and dynamically-adjusting delay circuits.

Abstract: A system for publishing data on shared broadcast channels using spread-spectrum techniques, which may comprise a spread-spectrum encoder capable of receiving data and placing it in a spread-spectrum signal format and a transmitter operating on a shared communication channel or frequency band, such as might be allocated to terrestrial point-to-point or broadcast communications. The shared communication channel may comprise a cellular system, in which data may be transmitted using spread-spectrum techniques using the transmitters and repeaters of the cellular system simultaneously with voice and other transmissions associated with the cellular system. A subscriber station may be capable of receiving using a plurality of different communication channels or frequency bands, such as a first receiver capable of cellular reception and a second receiver capable of satellite reception, at least one of which uses spread-spectrum techniques.

Abstract: In order for simulcast phase synchronization to be carried out autonomously by each base station, a highly accurate clock is provided in the central station and in each base station, and phase compensation is performed in accordance with time information from these clocks. As a result, simulcast synchronization that depends on the accuracy of clocks can be established, and the required synchronization accuracy can be obtained even when high transmission speeds are involved. The clocks can be corrected by a portable reference clock brought to each base station and central station site, and/or by a global positioning system installed at each base station and/or central station site.

Abstract: A method of transmitting paging messages over a paging system configurable to provide coverage over a primary geographic area or region and at least two subregions defined within the primary geographic region. The paging system consists of a plurality of paging transmitters that broadcast paging messages to the primary geographic region. Some of the plurality of paging transmitters are also assigned to broadcast to a particular subregion within the primary geographic area. During primary operation, for part of a predetermined period of time, all of the paging transmitters within the paging system simulcast paging messages to subscribers entitled to coverage over the whole primary geographic region. For a remaining period of broadcast time, each of the paging transmitters assigned to broadcast to a respective subregion broadcast paging messages intended for subscribers entitled only to paging coverage within that particular subregion.

Abstract: A method and apparatus assigns and utilizes sets of transmitters (206) to provide radio coverage in dynamically assigned simulcast areas for communicating simultaneously with portable transceivers (122). Transmitters are assigned (704) to the sets such that each set is assigned all transmitters dominant to at least one of the portable transceivers having a message queued therefor. A transmitter is defined to be dominant when it can affect communications with the at least one of the portable transceivers while different data transmissions are being sent from all other transmitters. A subset of the sets is determined (708), wherein no transmitter is assigned more than once in the subset. The sets of the subset are then simulcast (710) such that the transmitters assigned to each of the sets of the subset transmit the message queued for the at least one of the portable transceivers to which the transmitters of the set are dominant.

Abstract: The object of the present invention is to perform synchronizing adjustment of reception timings of radio waves at a reception point without the necessity of an approach line and a receiving station from an exchange to a receiver and without being influenced by a condition of approach lines to all radio base stations. Exchange 10 is connected to GPS 20 and includes, in the inside thereof, approach line supervision unit 75 for supervising a condition of the approach lines and calculating transmission delay times from the condition of the approach lines, transmission time setting unit 15 for setting a time at which transmission radio waves should arrive at an overlap zone, data base 30 in which position information of the overlap zone is stored, and a controller 35 for transmitting information to the radio base stations.

Abstract: A clock synchronization system for synchronizing a number of paging stations (24) with a system controller (23). Each paging station has a clock that includes a counter (52) that indicates the current local time and which is sequentially incremented by a counter advance signal applied thereto. A voltage controlled oscillator (58) generates the clocking signal that controls the advancement of the counter. A CPU (50) in the system controller monitors the time indicated by the counter and compares it to timing information received from a system clock. The timing information includes a time mark and a time mark send time. The system clock transmits to each paging system the time mark. At a future time, the system clock transmits the time mark send time which is the precise time at which the time mark was transmitted. The paging stations each measure the time interval between the time at which the time mark arrived and the time at which the time mark was transmitted by the system clock period.

Abstract: Within a desired service area, multiple transmitters at separately located sites simultaneously broadcast the same multi-channel, multi-program signal. Broadcast waves from the transmitters propagate substantially throughout the service area and overlap in a substantial portion of the area. The signals are broadcast as spread spectrum signals and the receivers include despreaders with rake capabilities to obtain enhanced output signals with multi-path reception. In the preferred implementation, the channels are 6 MHz wide channels broadcast in the super high frequency microwave portion of the spectrum. Each such channel carries a multiplexed digital data stream containing packets of information for a plurality of programs, e.g., television programs.