Abstract: A method and apparatus used by a communication system (100) to register communication system users which use service provider equipment. Multiple-user and special purpose single-user communication units (110) are provided and/or operated by service providers. MCUs (110) can be located on mobile vehicles or in fixed locations. The system along with MCUs (110) collect registration information and usage information for individual users (440) and individual MCUs (110). Service providers receive billing information concerning the usage of their MCUs (110) by communication system users. After communication system (100) registers each user whose registration information is contained within the at least one combined request message, communication system (100) provides communication services to each user and billing information services to the service provider for the communications service and the service provider furnishing the communications equipment.

Abstract: An on-board aircraft telecommunication exchange (32) provides communication and authentication services for M subscriber identity modules (SIMs) using N transceivers (36), where M can be greater than N. Associations between SIMs (56) and transceivers (36) are established when needed. Accordingly, a pool of transceivers 36 is provided to serve the collective needs of many subscribers. A SIM-based authentication process is performed (100) using a subscriber's original SIM (56). That authentication can be extended to a temporary SIM (106) that is substituted for the original SIM throughout the remainder of a flight. Alternatively, the original SIMs (56) may be locked in place and relinquished when a subscriber provides an appropriate PIN.

Abstract: Methods (100, 150, 200) and systems (10, 30, 41) are used to expedite access for a period of time for those subscriber units (30) which have previously executed the complete visited gateway access procedures. By checking certain information sent by a subscriber unit (30) upon initialization and determining whether the information falls within a predetermined period of time, the visited gateway (41) enables itself to receive calls directly from the subscriber unit (30) and informs the subscriber unit (30) that it (30) can send calls directly to the visited gateway (41). The subscriber unit (30) thereafter sends calls to the visited gateway (41) instead of to the home gateway (40) until it (30) is no longer allowed to do so.

Abstract: In a dynamic communication system (90) wherein communication parameters vary between transmissions, subscriber units (200) are susceptible to intermittent link blockages. These blockages can result in a loss of successive feedback, instructing subscriber units (200) of adjustments to link parameters to be employed in a subsequent transmission on a communication link (105). Dynamic link parameters are predicted (240) continuously throughout intermittent link fades and these predictions are employed during link blockages in an attempt to re-establish communications. In addition, the subsequent resynchronization process resynchronizes the link parameter predicting model (240) based on how long the signal was interrupted.

Abstract: Multiple, different, independent constellations (10, 20) of satellites (2, 21-23) share a portion of a common frequency spectrum such as a single carrier frequency. The satellites' antennas (11) may be either multi-beam or omni-directional, while those of earth stations (13, 14) are directional. When interference occurs between communications of a satellite (31) of a first constellation (10) and a satellite (41) of a second constellation (20), any of several interference-mitigation options may be employed, such as the first satellite (31) handing off communications to a second satellite (32) of the same constellation (10), or temporarily suspending communications. The remedial action may occur in response to either predicted or detected interference.

Abstract: A hybrid constellation satellite communication system (100) is established using two or more satellite types (110, 120) in different constellations. The two or more satellite types (110, 120) are connected to system control centers (140) via control links (105, 135) which provides a communication path from the satellite constellations to the system control centers (140). The two or more satellite types (110, 120) are also connected to subscriber equipment (150) via subscriber links (155, 145) which provides a communication path from the satellite constellations to the subscriber equipment (150). The first type of satellites (110) are interconnected using upper inter-satellite links (115). The second type of satellites (120) are interconnected using lower inter-satellite links (125). Control services and other time delay non-sensitive services are provided using communication channels established using the first type of satellites (110).

Abstract: A channel management process (68) is performed by a parent base station (36) of a radio telecommunications system (20) that exchanges channel usage data with neighbor base stations (38) within its local group (34). When channel usage data indicates a channel assignment conflict, that conflict is resolved in the base station (22) having the lesser loading of the pair of conflicting base stations (22). Channel usage requests received by a base station (22) are prioritized and sequentially processed, channels (58) being assigned for inter-cell handoff requests, then intra-cell handoff requests after inter-cell handoff requests, even when that assignment creates a conflict, and then channels (58) being assigned to new call requests after handoff requests if that assignment does not create a conflict.

Abstract: A satellite-based imaging system (100) is used to provide imaging services to users located anywhere on the earth. The surface of the earth is imaged, and the resulting images are geolocated using stars as registration marks on the images. The imaging system comprises a scene imaging system (120) which forms an image of a scene on a first section of a focal plane system (150), a second group of imaging systems (122-128) that form images of unmoving objects, that geolocate the scene on a second group of sections of the same focal plane system (150), and an internal self-consistent system timing mechanism. The satellite-based imaging system (100) stores the images and transmits the images to earth-based processing centers.

Abstract: With a constellation of low-earth orbiting satellites, instantaneous photographs of all large cities can be made available in real-time or near real-time. Those photographs can be downloaded to ground stations, and there photographically interpreted to determine traffic conditions. The use of high and low photographic resolution permit making distinctions between different causes of traffic conditions. A color-coded map may be generated showing all major roads and their current status, showing such conditions as light traffic, medium traffic, heavy traffic and traffic accidents or jams, for example. These color-coded maps or color-coded alphabetized lists of streets may be broadcast to subscribers (broadcast stations, companies or individuals). From the color-coded traffic report, the subscribers are updated about which routes to avoid and what the best detours are around the more congested areas.

Abstract: The system (10) and method (100) adjust reuse units when nodes (e.g., satellites (20, 22)) move in a communication system (10), such as satellites (20,22) moving in their orbits around the earth in a space-based communication system (10). The method (100) and system (10) computes interference potentials between a reference reuse unit in a first reuse unit table of a first satellite (20) and reuse units being used in second reuse unit tables in second satellites (20) that are adjacent to the first satellite (20); and when the interference potentials is less than a predetermined threshold, then assigns the satellite a non-interfering reuse unit for the specific time interval.

Abstract: A system (10) and method (100) selects one of the gateways (40, 41) to set-up and maintain signalling resources associated with a call. Instead of having two gateways (40, 41) handle signalling resources, a single gateway (40) becomes the serving gateway for one or both of the subscriber units' call segment. The system and method do not establish a transit connection between gateways (40, 41).

Abstract: A method (100) and system (10) are used to expedite access for a period of time for those subscriber units (30) which have previously executed the complete home gateway access procedures. By checking certain information sent by a subscriber unit (30) upon initialization and determining whether the information falls within a predetermined period of time, a home gateway (40) directly notifies a visited gateway (41) to handle the call setup and bypasses the need to reexecute the full access procedures at the home gateway (40).

Abstract: A system (10) and method (100) reduce an amount of signalling resources used for calls involving more than one gateway (40, 41). Instead of having two gateways (40, 41) handle signalling resources, one gateway (40) becomes the serving gateway for a subscriber unit call segment. For signalling cut-through, a call is set-up in the usual way with a transit connection established between gateways (40, 41). After normal call set-up completed, including voice cut-through, signalling cut through is invoked to remove the need to maintain the transit connection and one local connection for the duration of the call. The old local connection is replaced with a new local connection to the serving gateway.

Abstract: An emergency handoff method (50) reroutes or redirects communications from one channel in a cell (105) to another channel in the same cell (105) or a different cell (107). Handoff is initiated by a subscriber unit (SU) (100) when the SU (100) determines that an emergency handoff is needed. Once a new channel is needed, the SU (100) chooses a new, available channel to transfer its communication. After selecting an available channel, the SU (100) acquires the available channel. The servicing satellite which is providing the available channel then makes the constellation of satellites reroute or redirect the call data or the communication packets across the new channel to the SU (100).

Abstract: The call admission control method provides guaranteed bandwidth connections in a mobile telecommunication networks (10) that have varying topology and dynamic capacities. Method (100) provides a systematic way to decide when to admit connection requests in a low-earth or medium-earth orbit based satellite telecommunication system (10). A call admission controller, located in a ground control station (40) receives a connection request from an earth station (50) that may be forwarded from a satellite (21) in a constellation (20) of satellites. The call admission controller segments a call holding time into a sequence of time segments and determines whether a path exists through the network (10) that has the required minimum bandwidth for each of the time segments. If such a path exists, the connection request is admitted and the call goes through. Otherwise, the call is denied and communication is blocked.

Abstract: A data transmission system (5) transmits data between a transmitter (10) and a receiver (20). Each data packet frame (130) is made up of three parts: a header (131), a packet identifier number (132), and subframes of data (133). Error codes are generated corresponding to each subframe of data (133). The transmitter (10) will then check the error code to determine which subframes of data (133) contain an error. If there are errors in the data packet (130), then the receiver (20) stores the error-free subframes in memory and does not send an acknowledgment packet (140). The master (10) will retransmit the same data packet until it receives an acknowledgment packet (140).

Abstract: A cellular communication system (10) requests from subscriber units (30) to volunteer for handoff when a call resource shortage is about to occur. The subscriber units (30) may volunteer to handoff to another cell (24) depending on whether any adjacent or neighbor cell (24) provides adequate signal strength for servicing the on-going call. If there is another adjacent or neighbor cell (24) which provides adequate signal strength, the subscriber unit (30) can volunteer for handoff to the other cell. The cellular communication system (10) may accept the volunteer handoff request, whereby the subscriber unit (30) volunteering for handoff is handed-off to the other cell (24). However, the cellular communication system (10) may deny the handoff request. If the handoff request is denied, the subscriber unit (30) may have to drop the call or try to locate another cell to handoff its call before a predetermined amount of time expires.

Abstract: A satellite communication network (10) coordinates multiple steerable satellite beams (28) with user requests for connections requiring varying bandwidth in real-time. A control station (22) gathers user requests for connections (64) and transmits those requests (70) to a satellite (20) over an uplink (70). Requests for bandwidth (72) are processed in the satellite (20) where time slot assignments (74) and steerable beam schedules (84) are determined in response to user requests (74). Steerable beam schedule (84) and time slot assignments (74) are transmitted to subscriber units (24) and control station (22) over a broadcast downlink (86). Subscriber units (24) complete a data transfer interval of a call (62) while a steerable beam schedule (84) is executed in real-time.

Abstract: Methods (100) assign a subscriber unit (30) to be served by a gateway (40) based on such factors as the location of the subscriber unit (30), whether the call is to be intercepted and whether the serving gateway (40) is capable of servicing the connection request. The method (100) does not drop a call because the visited gateway initially assigned by the home gateway (40) is unable to service the connection request; but instead routes the call around disabled or congested gateways to an alternate visited gateway that is capable of servicing the connection request.

Abstract: Method (100) executed by congestion controller (26) in each node (20, 30, 40) of a network (10) determines whether congestion is going to occur or is occurring in a particular node (20, 30, 40). If congestion is imminent or occurring, a congestion status bit is set. Each time a data packet is received and the congestion indicator bit is set, congestion controller (26) increments a congestion counter. Each time a predetermined time interval expires, congestion controller (26) decrements the congestion counter. By using the congestion counter as an index into a credit table, a credit value is determined by destination node (31) that represents how many data packets are permitted to be sent from source node (30) to destination node (31). The credit value is sent to the source node via a message.