Abstract: The methods (300, 900, and 1200), and apparatus (140 and 800) of the present invention employ demand assigned spatial multiplexing in a satellite communication system (100) to efficiently accommodate varying demand for high data rate service while minimizing satellite antenna and radio system complexity in a ubiquitous coverage satellite system optimized for transporting packet data. In a preferred embodiment, the methods (300, 900, 1000 and 1200) and apparatus (140 and 800) of the present invention use a first set of signaling beams (210) to establish signaling uplinks and then direct traffic spot beams (220) at particular UE devices to support traffic uplinks in accordance with demand assigned multiple access (DAMA) parameters when and only when the UE devices have traffic data to transmit to a satellite.

Abstract: Methods (400, 500, 600, 700, 800, and 900) and a multi-layer service management system (300) enable mutilayer service management in a global network environment in a communication system (100) which includes a core network (230) and multiple Distributed Virtual Network Segments (DVNSs) (240). The system (300) includes a network service manager (315) capable of managing a set of services for operating the core network, DVNS service managers (DVNSMs) (345, 347) residing within a core side (340) and a product side (335) of each item of DVNS equipment (330) for managing a first and second set of services associated with the DVNS and also a set of value added services (352) provided through the DVNS equipment (330), and a processor/server 385 residing within customer premises equipment (CPE) (370) for enabling provision of value added services to the CPE.

Abstract: A method (300, FIG. 3) controls CU (140, FIGS. 1, 6) hand-off in a non-geostationary orbit (NSGO) satellite system (100, FIG. 1) without consuming large amounts of bandwidth or satellite processing power. Using method (300), a network control facility (NCF) (130, FIGS. 1, 5) divides the earth (102, FIG. 2) into suitable regions 200 (FIG. 2), or geographical areas of the earth sized so that all of the CUs (140, 142, 144, FIG. 1) within a region (200) can be handed-off as a group rather than handling each station individually. When it is determined through the method (300) that it is time to hand-off communications in a particular region, all CUs within that region are directed to effectuate a hand-off at substantially the same time.

Abstract: Methods (600, 700), an access controller (350), and a communication system (300) for optimizing utilization of a wireless communication link in a limited bandwidth communication system or network are provided. Statistical multiplexing is achieved by partitioning a wireless communication link (240) into multiple communication channels (250) and assigning communication sources (220) to communicate information over an air interface for a predetermined time interval, where the number of communication sources (220) assigned to the communication channels (250) during a particular time interval exceeds the number of available communication channels (250). The methods (600, 700), access controller (350), and communication system (300) disclosed also allow a system operator to provide varying levels of quality of service (QoS) guarantees in a communication system or network using statistical multiplexing by designating varying levels of QoS among the communication channels (250).

Abstract: A method and apparatus for detecting and tracking spread spectrum signals, such as Global Positioning System (GPS) signals, first obtain precision timing and frequency reference information from a relatively high-power, secondary signal, such as that emanating from a satellite of a low-earth orbit (LEO) satellite communications system, and then use such reference information to perform narrow-band detection of the GPS spread spectrum signal. Accordingly, spread spectrum signals are more efficiently detected and tracked, particularly in environments where they are attenuated by obstacles such as buildings or environmental barriers.

Abstract: A method (1300) and apparatus (300) combines a terminal blockage profile for a ground-to-satellite terminal with satellite location and motion data for one or more satellites (12) in a satellite communication system (10) to predict an impending service outage or impairment on a real-time or near real-time basis and reports such impending outages or impairments, and the expected duration thereof, to the terminal operator. The prediction of an impending outage or impairment also can include analysis of information concerning atmospheric conditions in the vicinity of the terminal location as well as other potential sources of a service outage or impairment.

Abstract: A cell relay network (38, FIG. 2) transmits cells having different priorities through a single virtual connection using several methods (100, FIG. 4; 200, FIG. 5; 300, FIG. 3). Congestion control is accomplished by a negotiation process between a network user's communication equipment at a source node (900, FIG. 9) and a network control element (1000, FIG. 10) associated with the network fabric 18 at the time of connection set-up. A source node (900) initially transmits a request for a connection to the network control element (1000). Along with a connection request, the source node also transmits a requisition for permission to transfer through the network during a predetermined time interval cells having multiple priorities. The network control element responds to the requisition by sending to the source node a connection admissions attributes message (44, FIG. 2) containing allowable connection attributes.

Abstract: A user terminal (110) includes a rotating electronically steerable antenna system (210) which combines coarse mechanical beam steering with fine electronic beam steering to provide full hemispherical coverage and enable hand-offs in a satellite communication system. The antenna system (210) comprises at least one antenna unit (and preferably two antenna units) including a mechanically rotatable base (330), an antenna holder (320) coupled to the mechanically rotatable base, and two electronically steerable antenna subunit (310) mounted on the antenna holder. Antenna system (210) also includes an antenna unit controller (260) adapted to control rotation of the mechanically rotatable base (330).

Abstract: A method and apparatus for providing an economically viable satellite communication system (100) for voice, data, and video using satellite diversity to augment capacity of the system, to mitigate the effects of network operational issues such as the effects of satellite failure and/or satellite blockage, and to maintain service links (180) in a cost-effective manner. Satellite diversity is incorporated into the communication architecture, along with the ability to utilize all satellites (110) within a communication range (or view) of one or more service regions (197). Management methods are used to allocate satellite diversity to enhance service and mitigate network operational issues. Satellite constellation (120) is designed to maximize the availability of satellite diversity as a resource.

Abstract: A method (400, FIG. 4) for beam management in a satellite communication system (10) which simplifies cell-to-cell hand-offs within a footprint (90) of a satellite (20) and between two or more satellites (20) is disclosed. The method includes the steps of providing multiple beam stripes (130, FIG. 2) extending across the footprint (90) in a direction corresponding to the direction of flight (60) of the satellite, grouping the beam stripes (130) into one or more beam groups (150, FIG. 3), and selectively associating hardware groups (300) comprised of hardware resources to support beam groups (150). Method (400) also can include steps (450-470) for determining and compensating for undesirable system effects arising as a result of the relative motion of the Earth (50, FIG. 1) with respect to satellites (20) of system (10). A satellite (20, FIGS. 10 and 11) designed and configured to execute method (400) also is disclosed.

Abstract: A method and apparatus have been described for combining multiple satellite constellations into a cooperative network. A GEO tier of satellites receives information to be broadcasted to earth. The GEO tier receives the information from global hubs, regional hubs, and local hubs. Local program material is combined with regional and global program material by either the regional hub or a GEO satellite.

Abstract: A laser transmitter (200, 300) includes a femptosecond pulse forming circuit (214, 308) and an ultra high-speed optical switch (218, 304) which enable the transmitter (200, 300) to generate a modulated pulse stream having pulses with widths of under 200 femptoseconds. The transmitted pulse stream is processed by a laser detector (500), including a wideband optical detector (504) and pulse stretching circuit (506), that regenerates information included in the modulated pulse stream.

Abstract: A method (100) for providing continuous communication service from a partially populated satellite constellation includes deploying one or more phases of satellites to populate one or more sets of orbital planes (210), and providing continuous communication service from the one or more sets of orbital planes. Satellites (320) in each phase of satellites can be positioned to reside substantially the same as a position in which they will reside in a fully populated satellite constellation thereby eliminating the need to relocate satellites in the fully populated satellite constellation. Also, a communication unit (600) and a method (700) for the communication unit to communicate in a satellite communication system having a satellite constellation capable of being deployed in a plurality of phases is provided. The communication unit is capable of communicating with the satellite communication system at various minimum elevation angles during various phases of deployment.

Abstract: A scanning array antenna (300) produces a directional beam by differentially rotating two, co-axial, flat phasing plate assemblies (302, 304). Each plate (302, 304) consists of a phase shifting means designed to efficiently pass incident radio frequency (RF) energy while imparting a particular phase shift to the energy. The energy can be supplied by a feedhorn (406) located behind the plates (402, 404) or can be introduced above the plates (508) and reflected by a ground plane (506) on the bottom plate (504). A method for producing the directional beam using the scanning array antenna (300) determines (804) the desired beam direction, calculates (806) the appropriate plate rotation angles (326, 328), and rotates (808) the plates (302, 304) at the appropriate time.

Abstract: In a telecommunication system (15) with at least one gateway (1), at least one subscriber unit (2), a system controller (3), at least one communication satellite (4) and global positioning satellites (5), communication satellite (4) provides positioning information to subscriber units (2). System controller (3) uses links (13,14) with communication satellites (4) to control links (10,11) and links (8,9). Subscriber unit (2) receives on link (6) positioning information which is used by subscriber unit (2) to determine which global positioning satellites (5) are overhead. Knowing which global positioning satellites (5) are overhead allows subscriber unit (2) to more quickly acquire and track the global positioning satellites (5) required to accurately geo-locate itself. Subscriber unit (2) computes accurate location data and can transmit this data to gateway (1).

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: A method for a network in a multi-network system to obtain access information for a subscriber unit (104) (SU) involves requesting (1306) access information from an access server (110) which determines (1208) whether a group to which the SU belongs can access the network or another network from the SU location. The access server (110) can also send (1228) information to a network which describes which other networks the SU group can access from the SU location. An access server apparatus (1800) includes a processor (1802) for making access decisions in a multi-network system, a memory device (1804) for storing access information (1100) for various networks, and at least one network interface (1806). A gateway (GW) apparatus (2000) contacts an access server (110) to obtain access information. An SU apparatus (1900) includes a processor (1902) for using information from the access server (110) to access a network.

Abstract: A method and apparatus for routing signals through a system (10) which has multiple destination nodes (12, 14) assigns one or more unique carrier frequencies to each destination node (12, 14). When a signal is received (502) by a transceiver (12), the transceiver (12) evaluates (504) the carrier frequency of the signal, and determines (506) to which destination node (12, 14) that carrier frequency is assigned. The determination (506) is made using a table (200) which associates carrier frequencies to destination nodes (12, 14). The table (200) is created (304) and updated by a control facility (20) which distributes (306) the table (200) to the transceivers (12). Once the transceiver (12) determines (506) the destination node (12, 14), the transceiver (12) can route the signal toward that destination node (12, 14).

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 power supply (10) including a virtual resistor. The power supply (10) includes (i) a power stage (11) having an input (12) for accepting unregulated power, an output (14) for providing regulated power, a control input (13) and a current sense output (16); (ii) a control circuit (15) including an error amplifier (19) having an inverting input coupled to the output (14) and an output coupled to the control input (13); and (iii) a virtual resistance generator (25) having an input coupled to the output of the error amplifier (19) and an output coupled to a non inverting input of the error amplifier (19). The virtual resistance generator (25) is for supplying a reference voltage (27) to the control circuit (15) such that a voltage present at the output for providing regulated power (14) as a function of current leaving the output for providing regulated power (14) provides an output virtual resistance.