Abstract: A system and method of construction of unique word sets together with an efficient method of implementing correlation with the members of the set is presented. The set of UWs is constructed by breaking a UW sequence in to equal length segments, and then multiplying this vector by an orthogonal matrix. First an arbitrary vector U is chosen of length K for a set of N UWs. Then a matrix H of size N×N is chosen. The columns of H are then repeated L times to form a matrix H?. The set of N UW consists of the rows of H?UT. N sub-correlations of the N segments of the vector U with the segments of the (suitably delayed) received signal is performed at the receiver. Then the N different outputs are obtained as Z=HCT, where C=[C0 . . . CN-1] is the vector of correlated outputs. The receiver only requires N correlators, each of length L, instead of length K, which provides a less complex and more efficient solution for detection of UW sets.

Abstract: An apparatus for PLL bandwidth expansion including a compensation filter and a phase locked loop, where the compensation filter is programmed with a compensation function derived based on programmable coefficients and parameters of a transmitting device, a frequency response of the phase locked loop, and a wanted frequency response.

Abstract: An apparatus for a dual mode low density parity check (LDPC) decoder including edge random access memory (RAM), last-in-first-out/first-in-first-out (LIFO/FIFO) RAM, channel RAM, and parallel datapath engines, where the datapath engines include a standard belief propagation decoding (SBD) datapath and a layered belief propagation decoding (LBD) datapath, where the SBD datapath includes a shifter, an accumulator, multiplexers, and a g( )_sbd calculator, and where the LBD datapath includes the shifter, the multiplexers, and a g?( )_lbd calculator.

Abstract: A multiple access scheme is described. One or more encoders are configured to encode a plurality of bit streams using Low Density Parity Check (LDPC) coding. The bit streams correspond to a respective plurality of terminals. The plurality of bit streams are converted to provide a multiple access scheme for the terminals.

Abstract: A method for efficient retransmission over a satellite network including transmitting data packets to VSATs, receiving retransmission requests for at least one of the data packets from the VSATs, generating a retransmission packet based on the retransmission requests using XOR summing, transmitting the retransmission packet to the plurality of VSATs.

Abstract: Methods, systems and software are provided for high order signal modulation based on improved signal constellation and bit labeling designs for enhanced performance characteristics, including decreased power consumption. According to the improved signal constellation and bit labeling designs for enhanced performance characteristics, designs for 8-ary, 16-ary, 32-ary and 64-ary signal constellations are provided. According to an 8-ary constellation, improved bit labeling and bit coordinates are provided for a 1+7APSK signal constellation. According to a 16-ary constellation, improved bit labeling and bit coordinates are provided for a 6+10APSK signal constellation. According to three 32-ary constellations, improved bit labeling and bit coordinates are provided for a 16+16APSK signal constellation and two 4+12+16APSK signal constellations.

Abstract: A method for inroute bandwidth allocation supporting multiple traffic priorities in a satellite network including generating a backlog report, transmitting the backlog report to an inroute group manager, receiving a bandwidth allocation from the inroute group manager, and servicing priority queues and transmitting data to a satellite based on the bandwidth allocation from the inroute group manager.

Abstract: A method for controlling data traffic with random early detection and window size adjustments including performing random early detection on incoming data packets, calculating a simple moving average of packet dropping probabilities for the data packets as calculated when performing random early detection, decreasing an advertised window size if the simple moving average is greater than a probability target plus a tolerance factor, increasing the advertised window size if the simple moving average is less than the probability target minus a tolerance factor, and not adjusting the window size if the simple moving average is not greater than a probability target plus a tolerance factor and not less than a probability target minus a tolerance factor.

Abstract: A method for traffic management and resource allocation on a shared access network including estimating a bandwidth capacity of a gateway, determining a demand rate of an IP gateway, allocating bandwidth to the IP gateway based on the demand rate, traffic priority, or traffic weighting, allocating bandwidth to the IP gateway in advance of demand when excess bandwidth is available, scheduling traffic at the IP gateway based on traffic priority, service plan of a VSAT, or physical layer properties of the VSAT, performing priority queue servicing of traffic at a gateway using a real time traffic priority queue, a non-real time traffic priority queue, two or more modulation and coding queue groups, and a code block queue.

Abstract: An apparatus for beam selection for a multibeam satellite communications system including a VSAT with a remote satellite dish for sending and receiving RF signals and processor for calculating a normalized distance metric for user spot beams, selecting the user spot beam with the lowest normalized distance metric, and finding an outroute on the selected user spot beam using the remote satellite dish.

Abstract: A system for gateway RF diversity using a configurable spot beam satellite including a satellite, a first gateway connected to a first VSAT population through the satellite by a first gateway spot beam and a first user spot beam set, a diversity gateway located outside of the first gateway spot beam for the first gateway, and a diversity control function to command the satellite to connect the first user spot beam set for the first gateway to a diversity gateway spot beam when the first gateway experiences service interruption.

Abstract: A method of assembling a satellite antenna including placing a first layer PCB including an alignment hole on an assembly fixture including an alignment pole, placing a solid foam spacer including an alignment hole on the assembly fixture, pressing the solid foam spacer onto the first layer PCB to adhere the solid foam spacer to the first layer PCB, removing an adhesive carrier film from a reflector patch of a reflector patch sheet including an alignment hole, placing the reflector patch sheet on the assembly feature, pressing the reflector patch sheet onto the solid foam spacer to adhere the reflector patch to the solid foam spacer, and removing a release liner from the top of the reflector patch sheet to remove excess material from the reflector patch sheet.

Abstract: A system for maintaining data connectivity in a satellite communications system including a satellite terminal with a ping mechanism, a satellite ground station, and a ping server, where the ping mechanism pings the ping server and restores data connectivity between the satellite terminal and the satellite ground station.

Abstract: A method for iterative estimation of a set of unknown channel parameters in a beamforming network including determining a first order estimate of offsets at measurement nodes and an estimate of the confidence in the initial estimate of the measurement nodes' offsets, and iterating, until a desired estimation accuracy is obtained, determining an improved estimate of a parameter set, and the confidence in the estimates, using the prior estimate of the offsets at the measurement nodes and determining an improved estimate of the offsets at the measurement nodes and the associated confidence values using the prior estimate of the parameter set and the corresponding confidence values.

Abstract: A broadband satellite communications system comprises forward error correction (FEC) encoder/decoder, interleaver/deinterleaver, puncturing/de-puncturing, scrambler/descrambler, bit to symbol mapping/de-mapping devices, modulator/demodulator, transmit and receive filter; operating in a time-division multiple access (TDMA) system where information is sent in a burst-by-burst fashion during the assigned time slot; supporting diverse traffic types such as voice over internet protocol (VOIP), control messages (DACCH) and keep alive burst (KAB) during silence period and multiple data rates.

Abstract: A system and method are provided for use with streaming blocks of data, each of the streaming blocks of data including a number bits of data. The system includes a first compressor and a second compressor. The first compressor can receive and store a number n blocks of the streaming blocks of data, can receive and store a block of data to be compressed of the streaming blocks of data, can compress consecutive bits within the block of data to be compressed based on the n blocks of the streaming blocks of data, can output a match descriptor and a literal segment. The match descriptor is based on the compressed consecutive bits. The literal segment is based on a remainder of the number of bits of the data to be compressed not including the consecutive bits. The second compressor can compress the literal segment and can output a compressed data block including the match descriptor and a compressed string of data based on the compressed literal segment.

Abstract: The present invention provides a communication system for use with a first source signal and a second source signal. The first source signal is on a first channel and includes M symbols, where M is an integer greater than 1. The second source signal is on a second channel and includes X symbols, where X is an integer greater than 1. The first channel is different from the second channel. The communication system includes a first modulator unit, a second modulator unit and an adder. The first modulator unit can generate a first modulated signal based on the first source signal and includes a first inter-symbol distortion estimating unit and a first stage predistortion unit. The second modulator unit can generate a second modulated signal based on the second source signal and includes a second inter-symbol distortion estimating unit and a predistortion unit. The adder can generate an added signal based on the first modulated signal and the second modulated signal.

Abstract: An approach for load balancing is disclosed. A user load is determined based upon data queued for transmission at each of the terminals. In addition, an inroute load corresponding to loading of inroutes serving the terminals is determined. A user-to-inroute distribution that minimizes variation of the inroute load is generated. The user-to-inroute distribution maps the user load to the inroutes. The user load is reassigned to the inroutes based on the determined user-to-inroute distribution. This arrangement has particular applicability to a satellite network that provides data communication services.

Abstract: An approach facilitates synchronization by providing: (i) a method to analyze the two-satellite synchronization problem in time-frequency domain; and (ii) a two-stage estimation method to accomplish timing and frequency synchronization. The embodiment facilitates satellite diversity. The embodiment applies to a system involving two or more geosynchronous satellites.

Abstract: Various approaches are introduced to provide link adaptation to maximize the resource utilization of the satellite network: (i) a method to adapt the transmission rate for packet voice and data traffics; (ii) a method to control the transmit power of packet voice and data channels; and (iii) a method to accomplish the feedback loop in a secured and correct manner.