Abstract: A communication system having a proxy architecture is disclosed. The system includes a platform that provides performance enhancing functions. The platform includes a spoofing apparatus that routes the information within the communication system. The spoofing apparatus receives spoofing selection and spoofing parameters from the platform and maintains the current parameters in one or more spoofing profiles. The spoofing apparatus routes packets of information throughout the communication system based on the spoofing selection and/or spoofing profile. The spoofing apparatus may also compensate for maximum segment size mismatches during the routing of information. This compensation may include dynamically resizing data segments or disabling three-way handshake spoofing. The above arrangement has particular applicability to a bandwidth constrained communication system, such as a satellite network.

Abstract: An approach is provided for providing quality of service reservations in a packet-based radio communication network is disclosed. Connection information including connection rate is extracted from a dataflow from an application requesting connection-oriented service. A request message is sent to a proxy for establishing a connection based on the connection information over the network, wherein the proxy configures a classification rule based on flow criteria from the request message and accordingly initiates establishment of the connection over the network to a destination terminal. A confirmation that the connection can be established is selectively received according to the connection information, wherein the dataflow satisfying the flow criteria from the application is transported over the established connection to the destination terminal. This approach as particular applicability to shared capacity systems, such as a satellite communication system.

Abstract: An approach for providing access in a communications system is disclosed. A network node (or terminal) generates duplicate bursts. The network node then transmits the duplicate bursts over a contention channel according to a pre-determined quality-of-service (QoS) designation. The contention channel can be established based on a diversity ALOHA protocol. The present invention has particular applicability to a radio communications system, such as a satellite network that provides data communication services.

Abstract: An apparatus including a protocol stack, the protocol stack including an application layer, a network layer, and a physical layer, wherein the physical layer comprises a hardware interface between the apparatus and a network, wherein network-level tunnelling of a packet from the network layer, the tunnelling creating a packet having a plurality of network layer source addresses and a plurality of network layer destination addresses, takes place in the apparatus below the network layer but above the physical layer, wherein a driver operating in the apparatus below the network layer but above the physical layer effects the network-level tunnelling, and wherein the driver is configured to generate a reply to an ARP packet received from the network layer of the apparatus.

Abstract: A method and apparatus for computing a schedule of channels is disclosed. The method comprises the steps of accepting a series of commands to tune a plurality of channels sequentially from an ordered schedule of channels; determining a duration of a time period between each of the series of commands; and prioritizing the schedule of channels according to the duration of the time period during which each channel is tuned. The apparatus comprises a user interface for accepting a series of commands to tune a plurality of channels sequentially from an ordered schedule of channels and a processor, communicatively coupled to a memory, the processor implementing a timer for determining a duration of a time period during which each channel is tuned and prioritizing the schedule of channels according to the duration of the time period during which each channel is tuned.

Abstract: Optical bond-wire interconnections between microelectronic chips, wherein optical wires are bonded onto microelectronic chips. Such optical connections offer numerous advantages compared to traditional electrical connections. Among other things, these interconnections are insensitive to electromagnetic interference and need not be located at the edges of a chip but rather can be placed for optimal utility to the circuit function. In addition, such interconnections can be given the same or other pre-specified lengths regardless of the placement in the module and they are capable of signal bandwidths up to 20 Gigahertz without causing a cross-talk problem. A method of fabrication of such optical interconnections using optical fiber, a laser or photodetector and etched mirror and etched V-shaped grooves.

Abstract: A method and apparatus for switching signals through a switch matrix are disclosed. The apparatus comprises an input module and an output module. The input module has a plurality of inputs typically equal to a number of cells in a reuse pattern, and the inputs receiving at least one uplink beam. The input module also has a plurality of outputs, the plurality of outputs is typically equal to the number of subbands in the uplink beam. The output module is coupled to the input module and selectively couples the outputs from the input module to an output of the output module. The method comprises the steps of grouping the uplink signals into a plurality of groups, the number of groups typically equal to a number of cells in the cell-based transmission matrix, where each group comprises a signal from each frequency used in the frequency reuse pattern. Each group of uplink signals is then separated into subband signals, which are then grouped together into groups of similar subband signals.

Abstract: An approach is provided for transmitting messages using low density parity check (LDPC) codes. Input messages are encoded according to a structured parity check matrix that imposes restrictions on a sub-matrix of the parity check matrix to generate LDPC codes. The LDPC codes are transmitted over a radio communication system (e.g., satellite network), wherein a receiver communicating over the radio communication system is configured to iteratively decode the received LDPC codes according to a signal constellation associated with the LDPC codes. The receiver is configured to iteratively regenerating signal constellation bit metrics after one or more decoding iterations.

Abstract: A method and system for tracking a time division multiplexed synchronization signal in a satellite communication system is provided. The signal is provided as a series of frames with beacon signals time division multiplexed into at least one time slot of each frame. The beacon signal in each frame comprises a unique word sequence, which is the same in each frame, and a portion of a PN sequence. The entire PN sequence is distributed into a plurality of frames forming a superframe. Frequency variations of the incoming signal are tracked at the satellite terminal by correlating the PN sequence of the incoming signal against early and late locally generated versions of the PN sequence in a discriminate circuit. The output of the discriminate is provided to a delay locked loop circuit of at least third order. The output of the loop is used to adjust the frequency of the VCO, which clocks the A/D converter operating on the incoming signal.

Abstract: A system and method is provided that employs a frequency domain interpolative CODEC system for low bit rate coding of speech which comprises a linear prediction (LP) front end adapted to process an input signal providing LP parameters which are quantized and encoded over predetermined intervals and used to compute a LP residual signal. An open loop pitch estimator adapted to process the LP residual signal, a pitch quantizer, and a pitch interpolator also provides a pitch contour within the predetermined intervals.

Abstract: A system and method is provided that employs a frequency domain interpolative CODEC system for low bit rate coding of speech which comprises a linear prediction (LP) front end adapted to process an input signal that provides LP parameters which are quantized and encoded over predetermined intervals and used to compute a LP residual signal. An open loop pitch estimator adapted to process the LP residual signal, a pitch quantizer, and a pitch interpolator and provide a pitch contour within the predetermined intervals is also provided.

Abstract: A method is presented describing how information and data is exchanged between a user's access terminal's mobility management and radio resource software layer in a satellite based telecommunications system, wherein the telecommunication system comprises one or more satellites, new and existing gateways, and a user's access terminal, which comprises a mobility management and radio resource software layer, the method pertaining to data and information flow between them, in response to various stimuli and conditions as the user enters into and out of various modes of operations, including deactivation, activation and illumination of a dark beam of a spot beam that is a shared resource.

Abstract: A communication apparatus that shares precise return channel uplink timing information includes a common symbol timing reference and one or more control stations that each transmit independent asynchronous DVB data streams which evenly share the common symbol timing. The control stations each include respective delay trackers to determine broadcast transmission delays associated with the particular control station and transmission path. Each broadcast data stream includes the same non real-time frame marker and a transmission delay message particular to the respective control station. A remote receiver receives one of the broadcast streams and timestamps the non real-time frame marker with a local time of receipt. A timing recovery circuit determines an upcoming return channel frame start time by adjusting the local time of receipt by the particular broadcast transmission delay and a unique receiver offset time.

Abstract: A system for managing return channel bandwidth in a two-way satellite communication network is disclosed. A plurality of transceivers transmit backlog information over a return channel via a satellite, wherein the backlog information specify an amount of queued traffic for the respective transceivers. A hub receives the backlog information and allocates a minimal amount of return channel bandwidth to each of the transceivers. The hub selectively sets a bandwidth level associated with the return channel bandwidth that is available based upon one of a plurality of predetermined bandwidth levels according to a predetermined criteria. The hub selectively allocates additional return channel bandwidth based upon the bandwidth level to the transceivers that require additional return channel bandwidth in excess of the allocated minimal amounts.

Abstract: An approach for allocating bandwidth in a satellite communication system is disclosed. The system includes a set of global queues that store bandwidth requests, which are received from a number of satellite terminals. The received bandwidth request include a high priority rate request, a low priority rate request, a high priority volume request, and a low priority volume request. A bandwidth control processor determines bandwidth request type and priority of the received bandwidth requests and places the bandwidth requests in the appropriate global queues based upon the determined bandwidth request type and priority. Each of the global queues corresponds to a data rate associated with of each a plurality of channels. The system also utilizes a set of local queues that correspond to the channels. The BCP moves the bandwidth requests from the global queues to the local queues. The BCP then allocates the transmission slots in response to the bandwidth requests stored in the local queues.

Abstract: A vector modulator including an offset QPSK modulator operative for receiving input data and generating a first output signal representing the modulation to be imposed on a carrier signal to effect offset QPSK modulation of the input signal and a second output signal representing an amplitude of the input data; and a frequency modulator including a sigma-delta modulator, operative for receiving the first output signal generated by the offset QPSK modulator, and generating a control signal representing the desired frequency of the carrier signal such that the carrier signal represents the input signal offset QPSK modulated.

Abstract: A method and apparatus for enhancing the performance of a network by performing selective spoofing. Selective spoofing provides the ability to discriminate among different connections and only allocate spoofing resources to those connections for which spoofing will actually improve performance. The selective spoofing functions described are applicable to a wide variety of communication links, including both slow and fast links, high latency links, and links with low and high error rates. The selective spoofing functions may be implemented either alone or in combination with other performance enhancing features, such as, spoofing the conventional TCP three-way handshake, local data acknowledgement, multiplexing multiple connections across a single connection, data compression/encryption, prioritization, and path selection. The selective spoofing features described are particularly useful for links with high latency and/or high bit error rates.

Abstract: A method, system, and software product for transmitting TTY/TDD signals in a system employing low bit-rate voice compression are disclosed. The method includes receiving an input signal and generating a teletypewriter (TTY) indicator signal from the input signal. Whether or not the input signal is a TTY signal including a TTY character, is determined based on the TTY indicator signal. A TTY packet including the TTY character of the TTY signal is constructed and transmitted if the input signal is determined to be a TTY signal. A method, system, and software product for receiving and decoding TTY/TDD signal is also disclosed.

Abstract: An approach for transmitting packets conforming with the TCP (Transmission Control Protocol) over a satellite communications network comprises a plurality of prioritized queues that are configured to store the packets. The packets conform with a predetermined protocol. A classification logic classifies the packets based upon the predetermined protocol. The packet is selectively stored in one of the plurality of queues, wherein the one queue is of a relatively high priority. The packet is scheduled for transmission over the satellite communications network according to the relative priority of the one queue.

Abstract: An approach for controlling bandwidth allocations for a switching system with transmission constraints is disclosed. A scheduler within a switching system generates bandwidth metrics for a destination site. A traffic control processing logic receives the bandwidth metrics. The traffic control processing logic includes a utilization module that determines utilization associated with the destination site based upon the received bandwidth metrics, and an error calculation module that computes the difference between the determined utilization and a target utilization. A gain and filtering module, which is also a part of the traffic control processing logic, computes a correction value based upon the difference between the determined utilization and the target utilization, in which the correction value being associated with the destination site. Further, the traffic control processing logic includes an adder that outputs a control value based upon a reference control value and the correction value.