Abstract: In accordance with the preferred embodiment of the present invention all remote units (113–118) participating in a group call can actively transmit uplink communications to their respective base stations (101–102) via low-data rate traffic channels (103–108). The remote units having the highest transmit energies are summed and broadcast to all remote units (113–118) participating in the group call. Because only those remote units having the highest transmit energies are summed and broadcast, network congestion is greatly reduced.

Abstract: In accordance with the principles of the present invention, a method and apparatus for filtered wireless communications is provided. The method provides a filtered wireless zone, preferably for second-generation cellular systems. Signal levels from surrounding cells are tested. The identities and frequencies of surrounding cells are received and a list of the available frequencies of the surrounding cells is established. An available frequency that is geographically distant from the handset is chosen. This available frequency has a low signal strength relative to the other available frequencies. The chosen frequency is established as a private frequency. The private frequency is transmitted at a geographical distance close to and thus at a high signal strength relative to the other available frequencies. Thus, the handset switches to the private frequency. In one embodiment, the frequencies of the cells are Global System for Mobile Communications (GSM) frequencies.

Abstract: During a group call, each remote unit (113–118) receives a downlink supplemental transmission (109–110) that contains high-speed data (e.g., video). A single supplemental channel is utilized for each base station (101–102). On the uplink side, the supplemental channel is shared among all remote units, however only one remote unit (113–118) is allowed to transmit at a time utilizing the uplink supplemental channel. A decision is made as to which remote unit is providing a highest-voice-energy fundamental channel uplink, and that remote unit is assigned the uplink supplemental channel. The remote unit, that is currently transmitting utilizing the uplink supplemental channel, has its transmission broadcast (via downlink supplemental channels (109–110)) to all other remote units participating in the multicast.

Abstract: Within a wireless CDMA communication system (100), at least one dedicated inbound code (232, 332, 414-416) and at least one dedicated outbound code (234, 334, 418-420) are provided solely for use in providing group calls. Based on a dedicated inbound code, a subscriber unit transmits a group call signal (505) and a base transceiver system receives the group call signal (703). In turn, the base transceiver system retransmits the group call signal based on a dedicated outbound code (709). Alternatively, or in addition, the base transceiver system sends the group call signal, along with information regarding the dedicated inbound code, to a controller (705-706). Subscriber units can receive group code updates (502, 602) indicating the particular dedicated inbound and outbound codes to be used within a given site. In this manner, the communication system can provide group call functionality in a public system.

Abstract: In a wireless code-division multiple access (CDMA) system (100), a talkgroup (101) of subscriber units is provided. A sub-group (102) of subscriber units, forming a part of the talkgroup is assigned at least one inbound code (416-417). The entire talkgroup is assigned an outbound code (415). Members of the sub-group may simultaneously transmit voice information (410-411) using the at least one inbound code, which voice information is summed (412) and re-transmitted to the talkgroup using the outbound code. Subscriber units in the talkgroup, but not included in the sub-group, are allowed to transmit voice information only after requesting, and receiving, an additional inbound code.

Abstract: A data communication system employs a method (400) for transmitting packetized data (100) using a combination of well known transmission techniques, such as TCP/IP and a novel compression process. A message type identifier (300) for the packet to be transmitted is first identified, which identifier comprises a packet type identifier (113) and a protocol identifier (114). The packet type identifier (113) distinguishes between control information and user information in the data packet. The packet is then selectively encoded (407, 411) using either a first or a second header compression technique, depending on the packet type identifier (113) and the protocol identifier (114). In this manner, an improved packet transmission scheme is envisaged, which gives a reliable solution for data transmission in a noisy RF environment and/or a bandwidth-limited environment.

Abstract: A bulletin board coordinates the service authorization for other communication systems. Service authorizations are periodically updated, with authorized communication units returning to the bulletin board at pre-scheduled times to receive the updates that extend service authorization for authorized communication services. The bulletin board transmits authorization information on known communication resources at predetermined times known only by authorized communication units.

Abstract: A method of allowing use of small, low-power communication systems (20) within the coverage area (11) of larger trunked communication systems. A low-power communication system re-uses the same communication resources used by the larger trunked system whenever sufficient distance exists between large system communication units and the low power system so as to avoid interference. Large system communication units may also be constructed to operate in a dual mode format so as to transmit and receive in a low power mode and on re-used resources, whenever near a low power system or to transmit and receive in a high power mode whenever else necessary.

Abstract: Processing of dispatch calls in a multi-site communication system begins when a source communication unit initiates a request for a dispatch call. The request is routed to a controller which assigns a controlled device to support the request. In addition, the controller identifies the destination communication units, which site each of the destination units are in, and what controlled devices are needed to support the dispatch call. Having identified the controlled devices, the controller assigns all of the controlled devices needed the same temporary network address. With all the controlled devices having the same temporary network address, the controlled device assigned to support the request can transmit the messages generated by the source communication unit to other controlled devices using the temporary network address. Thus only one representation of a message produced by the source communication unit is transmitted from the assigned controlled device.

Abstract: A communication unit may operate in either a trunking communication system and a cellular communication system when the coverage areas of each system overlap. Typically, the communication unit is affiliated with the trunking communication system and operates normally therein. When a call is received or being placed via the cellular communication system, the communication unit transfers its affiliation to the cellular communication system and operates therein. The communication unit is prompted by the trunking communication system to transfer its affiliation for incoming calls and does so automatically for outgoing calls. Once the communication ends, the communication unit transfers its affiliation back to the trunking communication system within a predetermined period of time.

Abstract: A dispatch communication system wherein a communication unit may move from the service coverage area of a first system to the service coverage area of a second system during a communication transaction without the need to re-initiate the call. Communication units and base sites under this invention are constructed to relay signals to and from the system where the call originated.

Abstract: A system is described for providing ISDN services on a PSTN to communication units from an ISDN interface within a resource controller. The communication unit is allowed access to a target such as a subscriber within the PSTN or a communication unit in another cell, in an ISDN environment through entry of a target access number. The ISDN environment may be changed by the communication unit before entry of a target ID number.

Abstract: Within a communication system having a plurality of communication system sites, each communication system site has a one cell re-use pattern of a limited number of communication resources. Communication units within the communication system utilize a redundant transmission of information such that the geographic separation of communication system sites utilizing the same communication resources is reduced.

Abstract: In a geographic region that contains a trunking communication system and a cellular communication system, wherein the coverage area of each system substantially overlaps, a method that transfers a private call from the trunking communication system to the cellular communication is disclosed. When a communication unit initiates a private call in the trunking communication system, it transfers its affiliation from the trunking communication system to the cellular communication system. Once affiliated with the cellular communication, the private call is placed to the second communication unit. The trunking communication system detects the private call and instructs a second communication unit to transfer its affiliation to the cellular communication system. Once both communication units are affiliated with the cellular communication system, the private call is conducted. Once the private call ends, both communication units transfer their affiliation back to the trunking communication system.

Abstract: A bulletin board communication resource provides a message to communication units regarding available communication systems in a particular geographic area. The bulletin board resource also supports registration of the communication unit with one or more of these systems as selected by the communication unit.

Abstract: A network (2) utilizing power conductor distribution and incorporating infra-red (IR) radiation nodes having IR transducers (4, 6, 8). The IR transducers are located in ceiling-mounted lighting fixtures (16, 18, 20) and are connected to power terminals in the lighting fixtures both for powering the IR transducers in operation and for communicating network information. The transducers are thus positioned optimally for good IR communication and require no additional cabling.

Abstract: A subscriber makes its hand-off decision based on time difference measurements between synchronization markers received from adjacent repeaters relative to the synchronization markers received from the subscriber's assigned repeater. The subscriber uses signal quality measurements to identify candidate repeaters with adequate signal level, and the time difference measurements to decide which of these repeaters is geographically closest. Thus, the subscriber unit makes hand-off decisions as its movement closes the distance to an adjacent repeater that can provide an adequate signal level.

Abstract: Shown, herein, is a method of allowing use of small, low-power communication systems within the service coverage area of larger trunked systems. The small, low-power systems are constructed to reuse at least some of the communication resources, also used by the larger system. The large system measures signal strength values of large cell communication units and transfers such values to the small systems. A small system compares the transferred values with a threshold and when the threshold is exceeded, reuses the communication resources under a TDM format within the small system.

Abstract: In a geographic region that contains a trunking communication system and a cellular communication system, wherein the coverage area of each system substantially overlaps, a method that transfers a private data transmission from the trunking communication system to the cellular communication is disclosed. When a data transmission unit is prompted to transmit data, it transfers its affiliation from the trunking communication system to the cellular communication system. Once affiliated with the cellular communication system, the data transmission unit transfers its data via the cellular communication system. The trunking communication system detects the requested data and routes the requested data to the appropriate data target. Once the data transmission unit has transmitted the requested data, it transfers its affiliation back to trunking communication system.

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.