Abstract: A method and device for monitoring a mobile telephone repeater are disclosed. The repeater is of the kind comprising an uplink (100) and a downlink (200) between two antennas (1, 2), wherein the repeater receives, amplifies and retransmits signals between a base station and a mobile telephone. A stability test is performed automatically, whereby a possible continuous and strong signal, being caused either by an instability involving a positive feedback between the two antennas or by a disturbing signal, is detected, whereupon the amplifying gain is adjusted in response to the result of the stability test. The test criterion includes the step of checking whether the level of the input signal in the respective amplifier chain exceeds a threshold value during at least a major portion of a measuring period.

Abstract: In a radio telephone equipment which includes a portable radiotelephone (100) and a booster (400), an output from the portable radiotelephone (100) whose output level is set according to a level control signal transmitted from a base station is amplified with a preset amplification factor by an automatic gain control circuit (22) provided in the booster (400). As a result, since the amplification factor of the amplifier in the booster and the portable radiotelephone are independently controlled, the booster can be connected to even a portable radiotelephone which is designed without considering that it will be connected to the booster.

Abstract: An apparatus and process for improving the performance of a cellular communication system using direct sequence spread spectrum techniques. The apparatus and process enable dynamic modification of communication system parameters including PN code length, chipping rate and modulation technique for transmission of a data packet. Modification is based on proximity of the transmitter and receiver, transmitter and receiver capabilities and other factors. The system evaluates tradeoffs between data transmission speed and communication range to improve system performance.

Abstract: An rf transmitter (319) used with a single cell battery (101) includes a voltage boost circuit (211) integral with a class S amplifier (290). An rf signal to be amplified is separated into its envelope (amplitude) and phase components. The phase component is applied to the input of a power amplifier (260). The envelope is applied to a pulse width modulator (275) which is used to modulate the voltage supplied to the power amplifier (260). The pulse width modulator (275) controls electronic switches (285, 286) which are disposed between the single cell battery (101) and the primary of a step up transformer (211). The secondary of the transformer (211) is coupled to supply voltage to the power amplifier (260). In this manner, the class S amplifier is powered directly from the single cell battery, via a the transformer (211), and power consumption is substantially reduced due to the switching operation of the switches (285, 286).

Abstract: An accessory apparatus for mobile radio telephones, particularly those used in cellular networks, permits utilization of the full communication range capability of a vehicle-mounted cellular radio telephone by a cordless portable handset remote from the vehicle. The apparatus includes a plug-in adapter unit located in a vehicle and interconnected between the existing handset and transceiver of the vehicle-mounted radio telephone. The adapter unit includes a first, resident, down-link transceiver operating at radio frequencies outside of the cellular frequency band, and adapted to receive demodulated audio and/or data signals from the resident cellular transceiver, and retransmit the signals via a low-power modulated down-link RF carrier signal to a portable remote cordless handset/transceiver.

Abstract: A portable RF telephone for use in a vehicle may be coupled to an external antenna to overcome the shielding effects of the metallic enclosure of the automobile. While coupled to the external antenna, the portable RF telephone increases the amount of power used to transmit an RF signal. Preferably, the transmit power increases to a maximum level allowed within a defined power classification. Increasing the transmit power overcomes cabling and connector losses associated with using an external antenna and further increases the effective transmitting power without exceeding power levels defined by the telephones power classification.

Abstract: In a first aspect of the invention, when it is expected to disconnect a booster during a call, the station class mark is changed to that applicable when a portable telephone is used as an independent unit in accordance with a key input from the user before the initiation of the call. In a second aspect of the invention, the telephone number of the remote party is stored in a memory during a call. When a connection or disconnection of a booster is detected, the call is terminated, and a redialing operation is automatically performed using the stored telephone number. In a third aspect of the invention, when the connection of a booster is detected during a call, an instruction is given to the booster to operate in a portable telephone mode. In a fourth aspect of the invention, when the connection or disconnection of a booster is detected during a call, a request to change the station class mark is sent to the base station.

Abstract: A system and method for indicating to a user that an operable-connection or non-operable connection has been made between a portable radio and a vehicle kit forming a mobile communication system. The system determines if an operable-connection has been made by determining if a hands-free-request signal, an external power signal, and an external antenna signal are present. Detection of the hands-free-request signal, external power signal, and external antenna signal are indicative that the portable radio and vehicle kit are operably connected such that the mobile communication system is fully operational. An operable-connection alert indicative of an operable connection between the portable radio and vehicle kit is generated by a radio display and an external speaker in response to a determination that the hands-free signal, external power signal and external antenna signal are present.

Abstract: A system and method are provided for controlling the output power from a mobile station based on the type of antenna used. The system and method detects whether the antenna is a type which is directly attached to an acoustic transducer for speech of the mobile station and controls the output transmission power based on this detection to conform with GSM requirements. More particularly, if the antenna is detected to be directly attached to the acoustic transducer for speech, and thereby to the hand set of the mobile station, the maximum output power of the mobile station is Class 4 or 5, which corresponds to 2.0 watts or 0.8 watts respectively, in order to comply with the GSM requirements. However, if the antenna of the mobile station is not detected to be directly attached to the acoustic transducer for speech, a higher maximum output power of the mobile station of Class 2 or 3, which corresponds to 5.0 watts or 8.

Abstract: A booster arrangement for a portable telephone, which includes a telephone (2) and booster (1), and which booster receives identity information from the portable telephone, is characterized in that it incorporates a security procedure in which the booster receives a security query from a mobile communication system and transfers it to the portable telephone, the telephone performs security algorithms and sends an result to the booster and the booster creates an answer to the security query based on the received result. The booster (1) checks the software and hardware versions of the portable telephone (2) and the security procedure is performed based on the version information. Reception of identity information by the booster from the portable telephone also is performed based on said version information. By means of the present invention, equally good security is obtained when using a booster arrangement as when using a portable telephone.

Abstract: A method and system for providing extension phone service within a mobile radio communication system. The mobile radio communication system includes a home location register (HLR), a plurality of mobile switching centers (MSCs), and a plurality of mobile stations. A single subscriber number is assigned to each one of the plurality of mobile stations. When a call is directed to the single subscriber number, the HLR transmits an individual routing request message to each one of the plurality of MSCs where mobile stations assigned to the single subscriber number are believed to be located. Each of the MSCs pages the mobile stations within its service area. Upon receiving a response from one or more of the paged mobile stations, each of the MSCs establishes voice channels with the responding mobile stations, and alerts the stations' subscribers. The MSCs then report to the HLR which of the alerted subscribers answered the alert.

Abstract: A paging receiver receives a message data including an overhead and a body data. The paging receiver has a first memory with multiple memory slots for holding the body data from multiple message data, and a second memory for holding information about the current storage methods for memory slots of the first memory. The overhead of the message data specifies a memory slot number for storing the body data, and also specifies a method of storing the body data, which may be storage by replacement of current contents, storage by combination with current contents, etc. A controller of the paging receiver selects the storage method from the second memory if the overhead does not specify the method of storing the body data, but uses the method specified in the overhead when present. The body data of the message data is placed in the specified slot of the first memory using the method selected by the controller.

Abstract: A communication transceiver (510) having a receiver (704), a controller (714) and a transmitter (710), is used for generating an unscheduled acknowledge back response. The receiver (704) receives an address and a color code identifying the cell transmitter (506) transmitting the address during a first scheduled time interval (212). The controller (714) selects, in accordance with the address received, a reserved response time slot from a predetermined number of reserved response time slots occurring during a second scheduled time interval. The transmitter (710) then transmits the unscheduled acknowledge back response during the reserved response time slot (224) selected.

Abstract: A paging device with a message display function enables a person who possesses the paging device to register plural calling numbers including an area code in a memory section by operating an attached input section. The paging device is arranged such that upon receiving a calling number, a calling number corresponding to the received calling number is searched in last-to-first sequential character order, from a calling number directory registered in the memory section, and the calling number including the area code is displayed on a display section. In this way, even when a calling person transmits the calling number without the area code, the calling number including the area code which is registered beforehand is displayed on the display section of the paging device.

Abstract: Method and apparatus in a selective call system for storing received messages in at least one receiving unit having memory and for processing a command to validate memory (358) when the receiving unit is idle, or the receiving unit is processing received messages, or when a central control unit is waiting for acknowledgement of a previously sent message. The method further includes detection of a corrupted memory (360), followed by erasure of the received messages (362) stored in memory and transmitting a "failed memory" acknowledgment signal (366). The method further comprises a step of receiving a reproduction of all of the received messages (370) erased by the receiving unit, or a reproduction of the most recently sent message, or a reproduction of the previously sent message for which the central control unit is waiting an acknowledgement.

Abstract: In a transmission circuit, part of the output signal of the transmission circuit is diverted by an output monitor circuit and subjected to envelope detection by an output detector circuit. The output signal of the output detector circuit is inputted to a peak hold circuit successively holding the peaks of the input signal, so that varying amplitude components are removed, and a DC value is detected. An error detector circuit compares the detected value with a reference signal from a reference signal generator circuit, and the error signal is used as a gain control signal to control the gain of a power amplifier circuit.

Abstract: A two-way selective call receiving device is responsive to the receipt of a message with an identifier falling within a limited set of possible identifiers in order to control the ability of the selective call receiving device to transmit a response to a prior message having the same identifier. The selective call receiving device utilizes a tracking table that stores information tracking received messages with their associated identifiers. A controller determines whether a prior message having the same identifier as a newly received message is stored in the device and for which a response has not already been transmitted. If so, the controller prevents a response to the prior message from thereafter being transmitted.

Abstract: In a digital half-duplex frequency division multiple access radio system a mobile station is either sending or receiving. For each call between a mobile station and a base station, a first frequency is allocated for the up link direction (from the mobile station to the base station) and a second frequency is allocated for the down link direction (from the base station to the mobile station). The signals exchanged by the stations are organized in frames of predetermined fixed duration grouped into multiframes comprising a predetermined number of frames including at least one control frame. At least some of the control frames are listening frames during which the sending mobile station interrupts sending, switches to receive mode and (if appropriate) reverts to send mode.

Abstract: A TDMA radio communication system such as GSM has a limited time period (td) over which the transmission from a mobile station (MS1 . . . MS5) can be advanced to allow for the transit time of the signal between the mobile and the base station (BS), and this limits the maximum range of the system to radius R1. By co-locating a first transceiver (TX1/RX1) operating on a first frequency band (F1) and a second transceiver (TX2/RX2) operating on a second frequency band (F0), and delaying the reception time slots of RX2 by td, the first transceiver can be used for communication up to radius R1, and the second transceiver can be used for communication for mobiles between radius R1 and radius R0. Idle mobiles are instructed to camp on F0 and RX1 is switched during access request periods to look for access requests on F0.

Abstract: A messaging system and method capable of transmitting group messages throughout a Network (200) such that receivers which are outside of a "local" or "home" area of coverage receive such group messages, whereas receivers which are in a "local" area of coverage over ride and do not receive the group message as a result of decoding system identifiers and ignoring those messages having network roaming identification.

Abstract: A method of mobile station synchronization to a system time, wherein the time alignment is attained while the mobile station operates in analog mode. The mobile stations transmits a periodic signal, each period of which has a leading edge. The base station detects the leading edge of the periodic signal and compares it to an indication of system time. The base station generates an error message for the mobile station indicating an update to the phase of the periodic signal. When the mobile station and the base station are time aligned, the base station may send a message indicating the absolute time at some future leading edge of the periodic signal thereby eliminating ambiguities of time due to the finite time required to receive the message.

Abstract: Packet data transfer in a digital cellular radio system including at least one common organization channel for sending pages, connection requests, and channel assignments so as to establish an actual connection on another channel. User data is transferred from the mobile stations to the base station interleaved with the connection request messages on at least one random-access-type organization channel in messages which will not result in a normal connection establishment. The mobile station sends a random-access-type packet data transfer request on the random-access-type organization channel. A timing advance corresponding to the distance between the base station and the mobile station is determined on the basis of the request received at the base station.

Abstract: A subcarrier signal generator includes a finite impulse response (FIR) filter responsive to selected FIR coefficients. A first set of FIR coefficients represents an ideal subcarrier shape and center frequency. A calibration step monitors the resulting subcarrier signal and produces a new set of FIR coefficients corresponding generally to the ideal subcarrier signal shape and center frequency, but predistorted according to the compliment of error detected in the actual subcarrier signal. By then loading the new set of FIR coefficients and operating the subcarrier generator, frequency-dependent distortions in the output stage of the subcarrier generator cancel predistortion reflected in the new FIR coefficients. As a result, a high quality subcarrier signal results without use of expensive output stage devices in the subcarrier signal generator.

Abstract: A "narrow band" public service trunking (PST) simulcast radio frequency transmission system having high-speed and low-speed digital data access capabilities in addition to analog voice operates in the 900 MHz frequency-range, as distinguished from a conventional "wide band" PST system that operates in the 800 MHz frequency range. In a narrow band PST simulcast system having digital access capabilities, the handling of low speed digital data must be accomplished differently than high speed data since it becomes unique to each channel. This would ordinarily require providing an additional data path for each channel, or a wider band width audio path neither of which is feasible or cost effective.

Abstract: This invention relates to an automatic, emergency or weather alert interface system between a first communication system, on which an emergency alert signaling tone is transmitted to indicate the occurrence of an emergence condition, and a second communication system, different from the first communication system. In operation, an emergency alert signaling tone is received from the first communication system by the emergency alert interface system which causes a prerecorded alert message to automatically be transmitted on the second communication system for an adjustable number of cycles wherein the audio from the prerecorded alert message is mixed with the audio from the second communication system so as to permit both audio messages to simultaneously be transmitted on the second communication system.

Abstract: A portable paging system communicates a paging message including a first portion having at least a selective call address (406) and a first activation code (407), and a second portion having a first segment (409) of an audio portion, to a selective call receiver (300). In the portable paging system, an input device (104) prompts an originator to request an extension of the second portion of the paging message, the extension including at least a second segment (410) of the audio portion. Upon receiving an affirmative talk time extension request from the originator, and if extending the second portion of the paging message does not exceed a predetermined number of extension requests or a predetermined total broadcast time allocated for the second portion of the paging message, a paging terminal controller (210) extends the second portion of the paging message.

Abstract: A paging radio communications system includes a plurality of radio receivers, a call controller for receiving a call message which requests a connection with at least one of the radio receivers and for generating a selective call signal having a predetermined format in which a preamble signal and a code word are provided, the code word including information specifying the at least one of the radio receivers, and a plurality of radio transmitters coupled to the call controller. Each of the radio transmitters includes a transmitter unit for transmitting a radio wave corresponding to the selective call signal without storing the selective call signal when one of predetermined transmission delay times has elapsed after receipt of the selective call signal, so that a part of the preamble signal and the code word are transferred to the radio receivers, and code words respectively transmitted by the transmitter unit of the radio transmitters are in phase with one another.

Abstract: In a space-division multiplex communication method of executing multiplex communication according to this invention, a plurality of radio beams a--a' to d--d' radiated at same frequency in different directions and rotated at same rotational angular speed .omega. are independently received in synchronism with the rotational angular speed .omega. by a plurality of communication terminals R1 to R3 arranged at arbitrary positions in a space where the radio beams can be received, thereby realizing unidirectional multiplex communication using the same frequency. Interstation bidirectional multiplex communication is performed by introducing a frequency-division system to the communication terminals R1 to R3 of the unidirectional multiplex communication. The space-division multiplex communication method can effectively use a frequency by a multiplex communication system of space-dividing a radio beam.

Abstract: Apparatus and methods for providing cellular mobile telecommunication service in accordance with the requirements of the Global Systems for Mobile Communications (GSM) standard. A modular switching system is provided which performs the functions of the mobile switching center plus those of a home location register, authentication center, visitor location register, and equipment identity register. The latter functions are advantageously spread among the modules of the switching system, thus avoiding the getting started cost of expensive dedicated data bases. A wireless global switching module advantageously switches mobile communications control messages among the modules of the system and between the modules and the base station systems, and terminates signaling links between the mobile switching center and the base station systems.

Abstract: In a communication system network, the central controller may more efficient respond to group regrouping requests in the following manner. Once a console generates a dynamic group regrouping request which requests the regrouping of a set of communication groups into a super group, the central controller determines, for each communication system, whether at least one of the set of communication groups is registered in that communication system. When at least one of the set of communication groups is registered in the communication system, the central controller groups the at least one of the set of communication groups into a local super communication group. Having done this, the central controller then generates super communication group information and transmits it to the communication systems but only that portion that pertains to the local super communication group.

Abstract: A system for allocating communication resources in a communication system where only a single frequency pair may be available for use by many users. A system wherein a resource controller transmits control information on a resource to many potential users without disrupting use of the resource by a primary user.

Abstract: A method of synchronizing a plurality of remote site transmitters (200) in a digital simulcast transmission system is described that enables use of four-level modulation on two-level modulation systems. A synchronization signal is transmitted at a predetermined data rate from a prime site, which signal might include a synchronization pattern having a first and a second portion. The first portion of the synchronization pattern is used for synchronization, while the second portion indicates the completion of the first portion. The method includes detecting (205, 320) of the first portion of the synchronization pattern. Each remote site transmitter (200) further has a modulation clock having a phase polarity which is selected (215, 324) in response to the detection of the first portion of the synchronization signal.

Abstract: A method for measuring a time delay between a controller (302) and a plurality of base sites (306) in a simulcast system (300). The method begins with the controller (302) transmitting a synchronization signal to a selected base site (306A) and to a delay measurement device (316). Upon receipt of the synchronization signal by the selected base site (306A), the selected base site (306A) transmits a signal to the delay measurement device (316). The delay measurement device (316) determines the time between the receptions of the synchronization signal transmitted by the controller and the signal transmitted by selected base site (306A). The delay measurement device (316) transmits the delay time determined between the receptions of the synchronization signal transmitted by the controller and the signal transmitted by the selected base sites (306A) to the controller (302) which programs the base sites (306) to delay transmissions of the RF signals in response to the measured delay time.

Abstract: An apparatus for simultaneously monitoring the heart rate of each of a plurality of subjects comprises a main circuit for transmitting a predetermined signal of predetermined frequency and duration and at predetermined time intervals to cause each of a plurality of remote subcircuits to transmit subcircuit identity data and heart rate data in predetermined timed sequence, a receiver for receiving remote subcircuit transmissions and producing an output representative of the heart rate of a subject and a plurality of remote subcircuits, each remote subciruit having a pulse monitoring device adapted to be secured to a subject for detecting and producing an output in response to a heart beat, and a detector for detecting the pulse monitoring device output and determining the number of the outputs which occur within a predetermined time interval, and being responsive to the main circuit predetermined signal for transmitting to the main circuit a signal representative of subcircuit identity data and the number of t

Abstract: A radiotelephone system having a base unit and a plurality of subordinate units for carrying out radiocommunication between the base unit and the subordinate units. The base unit sends transmitting carriers to the subordinate units and gets receiving carriers from the subordinate units. The system includes a first frequency varying part for periodically shifting transmitting/receiving carrier frequencies of the base unit from a given frequency of one operating interval to another frequency of another operating interval. A first synchronizing signal part generates a synchronizing signal in synchronism with a time period determined from the shifting of the carrier frequencies. A second synchronizing signal part extracts a synchronizing signal from a receiving carrier signal received by each of the subordinate units.

Abstract: A multiple transmitter message transmission system provides for the distribution of message packets from a central transmitter station to a plurality of remote transmitter stations on a common channel on which the messages are delivered to a plurality of paging receivers operating within the system. The messages are delivered by simulcast transmissions from the central transmitter station and the plurality of remote transmitter stations. The system is capable of functioning with a variety of signaling protocols, and reduces the number of channels required for message distribution and delivery to a single common channel.

Abstract: Method and apparatus for ensuring synchronism among modules of a distributed digital system (DDS) to a master clock signal is disclosed. The master clock signal is distributed at a frequency f.sub.c /N, and circuitry associated with each module multiplies the distributed master clock signal by N to provide a desired sync frequency f.sub.c to each module.

Abstract: A personal security system includes at least one movable transmitter adapted to produce an emergency signal transmission when activated and a plurality of transceivers adapted to receive emergency signal transmissions from the movable transmitter. The received strength of an emergency signal received by one of the transceivers is compared with the received signal strength of an emergency signal received by other of the transceivers, and an alarm signal is produced by a transceiver in response to receipt of a transmission whose signal strength is stronger than any other transmission signal strength to which it has been compared. The alarm signal may include a code identifying both the activated movable transmitter and the transceiver producing the alarm signal.