Abstract: A large scale hierarchical and heterogeneous network, and specifically mobile ad-hoc networks (MANETs), derive content elements from a plurality of informational data points via spectrum fusion at each hierarchical level. Content elements may be derived via fusion of information data from peer nodes and from content elements from lower hierarchical levels. Content elements are propagated up for further abstraction at higher hierarchical levels. Each content element is tagged with a node location and external reference direction. The node location and external reference direction facilitate fusion are each hierarchical level where the deriving node is receiving content elements from a plurality of different nodes.

Abstract: A system and method for managing acknowledgments and retransmissions in a distributed manner in a MANET with 2-hop clustering structure. Clusterheads are in charge of assuring delivery of flooding packets to their members. After receiving acknowledgments from associated nodes in the cluster, and clusterheads perform retransmission when necessary with a list of acknowledging nodes. The non-clusterhead nodes receive the retransmissions and determine if that node's acknowledgment was received based on a list of node IDs included in the retransmission. If the node ID is not listed, the node resends the acknowledgment. The process continues until all acknowledgments are received and listed.

Abstract: A system and method for incorporating co-site interference impact in dynamic spectrum access for heterogeneous hierarchical networks where preprocessing is used to create lookup tables for the different types of co-site interference. The lookup tables reflect the weight of the spectral leakage lobes for all signals internal and external to the system under different conditions. Lookup tables can be used at any hierarchical entity that offer dynamic spectrum access services in a cloud services construct. Co-site interference impact becomes its own set of dynamic spectrum access services that can be added to a dynamic spectrum access capable system without impacting the other dynamic spectrum access computations needs such as computation that produce spatial separation. Co-site interference becomes a second order spatial separation that is abstracted in lookup tables and adaptable based on measured metrics such that different lookup tables can be used under different conditions.

Abstract: A large scale hierarchical and heterogeneous network, and specifically mobile ad-hoc networks (MANETs), derive content elements from a plurality of informational data points via spectrum fusion at each hierarchical level. Content elements may be derived via fusion of information data from peer nodes and from content elements from lower hierarchical levels. Content elements are propagated up for further abstraction at higher hierarchical levels. Each content element is tagged with a node location and external reference direction. The node location and external reference direction facilitate fusion are each hierarchical level where the deriving node is receiving content elements from a plurality of different nodes.

Abstract: A communication node of a multi-node communication network may include a communication interface and a controller communicatively coupled to the communication interface. The controller may be configured to: transmit one or more data packets over an in-use channel to one or more additional communication nodes of the multi-node communication network; determine an in-use channel quality indicator (CQI) value (CQIin-use) of the in-use channel; determine a self-degradation value (SDV) indicative of channel quality degradation attributable to the multi-node communication network; determine a candidate CQI value (CQIcandidate) of an identified candidate channel different from the in-use channel; determine a first CQI difference value (CQI1diff); transmit one or more data packets over the in-use channel if CQI1diff does not exceed a CQI threshold value (CQIthresh); and transmit one or more data packets over the candidate channel if CQI1diff exceeds CQIthresh.

Abstract: A diversity code transmission system and method are disclosed. The method including demodulating a first transmission signal using a first continuous phase demodulator resulting in a first output and passing the first output to a first de-interleaver resulting in a second output. The method further including demodulating a second transmission signal using a second continuous phase demodulator resulting in a third output and summing the second output and the third output resulting in a fourth output. The method also includes passing the fourth output to a second de-interleaver resulting in a fifth output and decoding the fifth output to provide a symbol output. The method also includes passing a decoded fifth output to a first interleaver and providing a first interleaver output to the second continuous phase demodulator. Last the method is repeated in an iterative process.

Abstract: A method and system of demodulating a received transmission is disclosed. The method comprises disassembling a symbol sequence into a before sequence, a current symbol, and an after sequence. The method also comprises calculating correlations for all possible before sequences and determining the largest correlations for the before sequences, and placing into a first group. Further, the method comprises calculating correlations for all possible after sequences and determining the largest correlations for the after sequences, and placing into a second group. Further still, the method comprises piecing together the sequences of the first group, the second group, and the current symbol, to form a third group. Yet further still, the method comprises calculating the correlations for the third group and determining the largest correlation of the third group.

Abstract: A diversity code transmission system is disclosed. The diversity code transmission system comprises an encoder encoding a set of bits. The system also comprises an interleaver receiving the encoded bits and providing an output. A coder or modulator for providing a first transmission signal is also used. The interleaver iteratively receives its own output to provide an iterated output to a coder or modulator to provide a diversity transmission signal. The receiving system supports iterative decoding and joint iterative demodulation and decoding.

Abstract: An equalizer is used with complex modulation modems to reduce intersymbol interference. The equalizer includes an equalizer filter that receives an input data signal and adapts to compensate for the noisy communications channels to reduce intersymbol interference to the input signal. A branch metric computer demodulates the equalizer filter adapted input data signal. A decision device delivers an alpha value, starting phase information and confidence values from the demodulated input data signal. A gain determination function receives the confidence values and determines adaptation gain for the equalizer filter. A remodulator receives the alpha value and starting phase information and remodulates the alpha value and starting phase information into a remodulated data signal. A summing function compares the remodulated data signal to a delayed version of the input signal to generate an error signal for the equalizer filter to adjust the equalizer filter.

Abstract: A bandwidth efficient advanced modulation waveform modem using concatenated iterative turbo coding and continuous phase modulation is disclosed. A demodulator in the modem has a turbo decoder and a decision feedback carrier and time tracking algorithm to track a carrier and adjust timing. The decision feedback carrier and time tracking algorithm may use an APP decoder as a decision device to provide symbol decisions at a high error rate and low latency for a coded input data stream. A symbol phase estimator produces a symbol phase error estimate from the symbol decisions. An erasure decision function decides which symbol decisions are correct and which symbol decisions are erasures. A carrier tracking function receives the symbol phase error estimates when the symbol decisions are correct and receives erasure inputs when the symbol decisions are erasures to maintain carrier tracking.

Abstract: A method and apparatus for receiving data over a dispersive media is disclosed. The received signal is composed of an unknown data segment preceded and followed by known data segments. A replica of each known data segment is generated by the communication apparatus. Channel characteristics existing at the time of transmission of the known data segments are estimated by comparing the known data segments with the replica. Using estimations of the channel characteristics, symbols of the unknown data segment can be determined. Decisions can be made on the various unknown symbols as they are analyzed. Channel characteristics can be re-estimated after determining each symbol, each pair of symbols or each group of symbols. Two solutions of the unknown symbols can be combined in various ways to arrive at a final determination of the unknown transmitted symbols.

Abstract: A method and apparatus for receiving data over a dispersive media is disclosed. The received signal is composed of an unknown data segment preceded and followed by known data segments. The communication apparatus generates a replica of the known data segments. Channel characteristics existing at the time of transmission of the known data segments are estimated by comparing the known data segments with the replica. The symbols of the unknown data segment are then determined via application of a QR factorization. Factorization can be accomplished via Householder transformation, Givens rotation or fast Givens rotation. Decisions can be made on the various unknown symbols as they are analyzed and then fed back via back substitution.