Motorola Corporation

Kenneth M Peterson

Raymond Joseph Leopold

Bary R Bertiger

Yih Guang Jan

Keith Andrew Olds

Kadathur S Natarajan

Victor H Cutler, Jr

Gerald Joseph Davieau

Sam M Daniel

Randy Lee Turcotte

Rodrigo Ibanez-Meier

Brian Michael Daniel

William George Schmidt

Peter J Richetta

Amir David Foroudi

Yih G Jan

Michele A Pullman

Mukund Narain-dhami Thapa

Information packets are error encoded for transmission through a communication channel ( ) in a communication system ( ) using a variable payload outer code and a common physical layer inner code. The variable payload outer code is selected for each packet based upon an application or service associated with the packet. Thus, less coding can be used for packets associated with error tolerant applications and more coding can be used for packets associated with error sensitive applications. A common header outer code is also used for the packets. The variable payload outer code is preferably applied at the system adaptation level within an interworking function ( ) in the communication system ( ). The common header outer code and the common physical layer inner code are preferably applied at the data link layer.

Method for error correction in a communication system

Methods (,), an access controller (,), and a communication system (,) 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 (,) into multiple communication channels (,) and assigning communication sources (,) to communicate information over an air interface for a predetermined time interval, where the number of communication sources (,) assigned to the communication channels (,) during a particular time interval exceeds the number of available communication channels (,). The methods (,), access controller (,), and communication system (,) 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 (,).

Air interface statistical multiplexing in communication systems

A transmitter system (18) which transmits a communication signal (14) through a phased-array antenna (10) uses a signal processor (26) and a multiplicity of direct modulators (30). Each direct modulator (30) drives a single element (12) of the antenna (10). Each direct modulator (30) receives a digital baseband phase point data signal (62) from a digital data stream (28). The digital data stream (28) also conveys digital beam formation data (60). Each direct modulator (30) digitally combines the baseband phase point data (62) with the beam formation data (60) to produce digital streams that modulate an RF carrier signal (34). The digital data stream (28) is generated by a phased-array signal processor (26) which processes user data bits (86) received from any number of input signals (22) and processes beam signals (24). In one embodiment, the signal processor (26) calculates phase point data (62) representative of all input signals (22).

Transmitter system and method of operation therefor

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.

Method and apparatus for laser communication through a lossy medium

A cellular communication system (10) forms cells (18) from low earth orbit satellites (12). The system (10) uses an off-line process (24) to identify cells (18) that fall within various reuse distances of other cells (18) and to save system usage statistics. An on-line process (42) associates a demand with each cell (18), and the demand is predicted from the system usage statistics. Need factors assigned in response to the cells' demands are ranked and processed by an inner loop that assigns the various ones of the cells (18) to one channel (22) at a time and an outer loop that performs the inner loop for many different channels (22). The inner loop assigns cells (18) to a selected channel (22) in accordance with the need factor ranking.

Cellular communication system with efficient channel assignments and

A telecommunication network (10) includes satellites (12) in which cellular base station switches (42) are located. Each switch (42) is hardware configured to require the use of relatively few interconnection segments but would suffer a significant amount of call blocking if operated in a conventional manner. A new call setup process (96) is performed whenever a request to setup a new call is received at the switch (42). The process (96) defines new connections through switch 42 for ongoing calls while simultaneously defining a new connection for the new call. In addition, the process (96) forces the new connections to use only those interconnection segments that are reasonably required to implement the new connections. Segments that are not required are deactivated (128) to reduce power consumption.

Adaptive switch resource allocation in a satellite communication system

A central controller (40) executes a method (100) that selects and assigns channels to serve mobile subscriber units (30) in a space-based mobile telecommunication system (10). The method (100) is based on simultaneous consideration of a number of criteria that affect overall system performance of the mobile telecommunication system. Another method (200) assigns serving cells (15-18) by matching the available channel resources with actual caller demand as a function of time. The methods (100, 200) may be used in systems where the actual demand (i.e., offered subscriber traffic) and the number of channels available in each cell (15-18) is varying over time.

Centralized dynamic channel assignment controller and methods

In a satellite cellular communication system (10), a phased array antenna (41) includes a dynamic beamformer (50) that provides individual antenna beams (35) within which communications with subscriber units (26) take place. The satellites (12) are located in several orbits (14). As the satellites move with respect to Earth's surface, each of the antenna beams is stepped backward (104) to compensate for the satellites movement. After each satellite travels a distance equal to a predetermined portion of the satellites' spacing in the orbit, each satellite's antenna beams are stepped forward (116) to replace the previous satellite's footprint. Accordingly, cell-to-cell hand-off is not required for subscriber units communicating within an antenna beam.

Method and beam stepping apparatus for a satellite cellular

In a satellite cellular communication system, subscriber traffic is shared between satellites whose antenna coverage patterns overlap during some portion of their orbit. When the power consumption of one satellite exceeds a predetermined level, subscriber units are transferred to cells of a second satellite whose antenna coverage pattern overlaps that of the first satellite. After the subscriber units are transferred, channel assignments are redone to prevent interference with subscriber units in other cells.

Method and apparatus for load sharing in a satellite communication system

A system for facilitating global cellular/trunked mobile communication is disclosed. This system permits communication with hand held and mobile mounted cellular telephones. The system permits two-way communications anywhere on or above the earth up to a particular height above the earth of several hundred nautical miles. The system employs a number of low-earth orbiting satellites moving about the earth in orbit. Links are provided from the satellites directly to the users and via the public switched telephone network to other users. The satellites are interconnected via links in a ring structure surrounding the earth. Switching is performed by each of the satellites. In addition, each of the satellites hands off a call as it moves out of the range of a particular user.

Satellite cellular telephone and data communication system

A method and apparatus for controlling communication channel access in a communication system (10) determines channel allocations (106) which represent limits on communication channel access and conforms operations of the system (10) to the channel allocations. The channel allocations are determined by dividing a surface which emanates signals from communication units (26) into elemental areas, collecting past traffic data (102) describing past communication channel usage by the communication units (26) located in the elemental areas, generating a traffic model (104) for a future time interval based on the past traffic data, and determining the channel allocations (106) based on the traffic model.

Statistically robust traffic modeling method and apparatus

In a system that includes a constellation of satellite communication nodes, information packets are routed through the constellation using routing tables stored in each communication node. When a packet is received at a node, the packet's destination and routing table ID are read. One of several routing tables are selected using a mapping table. Each of the several routing tables has a different routing instruction set. The packet is routed away from the node using the selected routing table. When system traffic is heavy, or some of the communication links are overloaded or have failed, routing table control bits are sent to the nodes updating the mapping table. Packets are subsequently routed using different sets of routing tables, such as ones having greater hop counts.

Packet routing system and method with quasi-real-time control

Orbiting satellites (12) project footprints (30) on the earth. Each footprint (30) is divided into cells (28). Footprints (30) of nearby satellites (12) overlap one another, and the overlap increases as satellites (12) approach a pole from the equator. Positions of all cells (28) generated by all satellites (12) are simulated (36) at numerous points throughout an orbit. Channel sets are assigned to cells (28) within a reference footprint (30a). This assignment is propagated throughout all footprints (30) except for those footprints (30) residing adjacent one side of a seam (16) between orbits (14) where satellites (12) travel in opposing directions. The channel sets are assigned near the seam (16) in response to previously assigned channel sets. Each satellite (12) stores channel set assignments for its cells (28) at various points throughout its orbit. All satellites (12) switch their communication parameters simultaneously in response to the channel set assignments.

Communication system employing spectrum reuse on a spherical surface

A power management system for a worldwide multiple satellite system having satellites positioned latitudinally in a polar orbiting constellation, each satellite having a plurality of antenna beams, each beam having a given area of coverage or 'cell,' the total sum of the cells for each satellite forming a larger coverage for the entire satellite, the satellites each comprising solar cells and batteries wherein the energy within the batteries is generated by the solar cells and must be efficiently managed. The system comprises an earth based control station which programs each of the satellites within the constellation to supply power to the antenna beams of each satellite at predetermined times to avoid overlapping coverage. Each satellite comprises a voltage regulated linear power amplifier to supply only the power needed for the demand within each of the antenna's cells.

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Phoenix, AZ, United States of America

Kenneth M Peterson