Abstract: A trunked communication system having reassignable talk-groups. By having the talk-groups reassignable, the trunked communication system can accommodate a large number of user groups without adding to the control resource traffic congestion.

Abstract: An RF conductive shield can be fabricated from, and adhered to, a nonconductive substrate in the following manner. The RF conductive shield is fabricated in a predetermined geometric shape on the nonconductive substrate. Once the RF conductive shield is fabricated, it is cut from the nonconductive substrate to produce a separate RF shield. Having a separate RF shield, it can be placed on the nonconductive substrate in a predetermined location and adhered thereto.

Abstract: In a trunking communication system that is equipped to utilize the control channel as both a voice and control channel, a communication unit can transmit control data to the communication resource allocator in the following manner. Once a voice channel is selected as a voice/control channel, a communication resource allocator transmits the selection to the plurality of communication units. Thus, when the control channel is functioning as a voice channel, the communication unit can transmit a control request to the communication resource allocator via the voice/control channel.

Abstract: A communications system receiver (100) is disclosed which receives a transmitted signal over a radio channel. The transmitted signal includes data and a predetermined synchronization sequence. The receiver (100) includes a demodulator (215), and a stored replica (207) of the predetermined synchronization sequence. The receiver (100) further includes apparatus (102) for computing (308) a reconstructed signal, by using the channel impulse response characteristic and the stored replica (207) of the synchronization sequence. A feature of the invention is to estimate (310) a phase offset value between an incoming signal and the reconstructed signal, for a plurality of synchronization symbols. This serves to establish (315) a relationship between the phase offset and a synchronization symbol index. The receiver then employs this relationship to derive (317) at least one "previous" phase state (214) for initializing (314) the demodulator (215).

Abstract: In a digital summing process that sums non-linear digital signals by converting them to linear signals, computing their two's complement, summing the two's complements together and converting the resultant into a non-linear resultant, the fidelity of the summing process may be verified in the following manner. When only one non-linear digital signal is being summed, an algorithm determines whether the one non-linear digital signal being summed is equivalent to a predetermined value which, when passed through the summing process, will yield a different value than the one inputted. If the algorithm determines that the one non-linear digital signal is equivalent to a predetermined value, it sets a flag which indicates that the resultant over written with the predetermined value. Once the resultant is overwritten with the predetermined value, the flag is reset.

Abstract: A queueing and dequeueing mechanism for use in an integrated fast packet network, wherein fast packets from differing traffic types are multiplexed with one another through use of a weighted round-robin bandwidth allocation mechanism (517). Fast packets within a particular traffic type are selected for transmission through use of a head of line priority service (514), a packet discard mechanism (516), or both. The weighted round-robin bandwidth allocation mechanism functions, in part, based upon a credit counter for each queue group that represents a particular traffic type.

Abstract: In a Viterbi Algorithm decoder (204) as used to decode convolutionally encoded information, reliability information is developed for various path discard decisions made within the Viterbi Algorithm. These decisions are made for discard opportunities that impact one or more error detection windows (601). Based upon these metrics, a reliability factor sequence can be provided and compared against a fixed (or varying) threshold. When unreliability appears, appropriate action can be taken. For example, all of the information can be discarded, or only certain portions of the information can be discarded, as appropriate to the particular application.

Abstract: The present invention discloses a communication system network that comprises a plurality of communication systems and a processing multiplexer. The communication systems, which may be either conventional communication systems and/or trunked communication systems, transmit digitized audio signals and communication system data to the processing multiplexer. Based on signal destination data, which is part of the communication system data, the processing multiplexer processes the digitized signals and routes the resultant signals to the appropriate signal destinations.

Abstract: In a communication system that comprises a plurality of communication groups, a plurality of transceivers, and a plurality of consoles which monitor selected communication groups, a console may quickly monitor an unmonitored communication in the following manner. When the console detects activity in a particular unmonitored communication group, that communication group is placed into a receive queue. Once the communication group is in the receive queue, a dispatcher of the console may select the communication group and place it into a monitoring queue. Once in the monitoring queue, the dispatcher has full monitoring capabilities over that communication group. Once the dispatcher is done with the communication group, or call activity ends in the communication group, the communication group is placed back into a system group list.

Abstract: In a network of communication systems, control channel traffic can be reduced in a communication system in the following manner. When a source communication unit initiates a communication with at least one target communication unit, that source communication unit generates an individual reference address for the target communication unit and stores that individual reference in an internal data base. Having generated the individual reference address, the source communication unit transmits the reference address to the communication resource allocator of the communication system that it is registered in. The communication resource allocator then determines whether the individual reference of the target communication unit is stored in a reference address data base, located within the communication resource allocator, for the source communication unit.

Abstract: A carrier/insertion apparatus that has a U channel handle is improved to comprise an insertion portion, a stabilizer plate, and a deflector portion. The substrate that the carrier/insertion apparatus is mounted on comprises a carrier/insertion apparatus interface region that allows the carrier/insertion apparatus to mate thereto. As the carrier/insertion apparatus is slid into place, the deflector portion deflects the substrate a predetermined distance such that the carrier/insertion apparatus can be snapped into place. This arrangement allows for the carrier/insertion apparatus to be mounted on to a substrate without the use of mechanical hardware.

Abstract: In a communication system network that includes a processing multiplexer, a plurality of communication units, and a plurality of communication systems, each of the plurality of communication systems includes a base interface modules for interfacing the communication system with a limited number of repeaters that transceive information amongst the plurality of communication units and a processing multiplexer interface module for interfacing the communication system with the processing multiplexer. Each processing multiplexer interface module includes a base interface database that stores base interface status information of the base interface module of each of the plurality of communication systems that is periodically updated. The base interface database is updated when a processing multiplexer interface module of one of the plurality of communication systems detects a change in the base interface status information of the one of the plurality of communication systems.

Abstract: During an existing communication between a first communication unit and at least a second communication unit, any communication unit in the existing communication may add another communication unit to the communication. This may be accomplished by initiating a request to add another communication unit. The request is routed to the affiliated system data database circuits, wherein each system data database circuit reserves an entry in each signal destination field affiliated with a communication unit that is participating in the communication when an entry is available. With the entries reserved, each of the system data database circuits adds, in the entries, individualized information of the new communication unit such that the new communication unit can now participate in the communication.

Abstract: In a trunked communication system with at least two communication sites, a call hand-off mid-call may occur when a mobile radio (109) moves from the coverage area of one site to the coverage area of another site. This second site may not have any communication resources available for this hand-off, and the radio (109) is issued a busy message. With user selectable site switching, the user may enter into the radio (221) the desire to return to the previous site, and the radio moves to the previous channel to continue (229) receiving the call.

Abstract: Discrete packets (306) containing encoded voice information are transmitted within frames (301 and 302) in a repetitive manner until all voice information has been sent. Following transmission of all packets containing such voice information, at least a predetermined number of additional packets (401) are then transmitted, which additional packets represent silence. Following this, a disconnect signal (304) is transmitted. So configured, loss of the disconnect signal due to fading or other communication pathway disturbances will not necessarily lead to audibilization of undesired sounds, as the decoding protocol at the receiver (200) provides for reprocessing of recently received packet information in the absence of newly available reliable information. Hence, the silence information is continually reprocessed until either reliable information is again available or a time out sequence concludes.

Abstract: A method of recovering a frequency modulated signal wherein the frequency modulated information signal is sampled at a rate less than the Nyquist sampling rate, following which the under sampled signal can be demodulated to extract the original information signal.

Abstract: A trunked communication system wherein some of the communication resources are preassigned for exclusive use only by a predetermined group, such as a public safety agency. In addition, to assure optimal assignment of communication resources, communication resource assignments are made pursuant to a methodology that minimizes usurpation of unused resource capabilities.

Abstract: In a geographic region that contains a trunking communication system and a cellular communication system, wherein the coverage area of the trunking system and cellular communication system substantially overlap and wherein some communication units are located within the geographic region, a method is disclosed for a trunking communication system to locate a particular communication unit. In order to locate a particular communication unit, a communication channel controller of the trunking communication system transmits a location request to the particular communication unit. Upon receiving the location request, the particular communication unit transfers its affiliation from the trunked communication system to the cellular communication system. Once affiliated with the cellular communication system, the particular communication unit transmits a location message to the communication channel controller via the cellular communication system.

Abstract: A method and apparatus for operator messaging within a radio communication system (200) using a resource controller (203), which allocates a plurality of communication resources among a plurality of communication units (213, 215), is disclosed. Each of these communication units may be used by an operator having an operator code (262) and associated with a message (264, 266). This operator code and message, along with identification codes (252) representing each of the plurality of communication resources, are stored in a database (201) within the resource controller (203). The method includes the transmitting of the identification (ID) associated with a transmitting communication unit, matching this ID with one of the stored identification codes (252) in the database (201), and using this code to retrieve the message (254, 256) associated with the operator of this communication unit.