Abstract: Examples of check codes, methods of creating check codes, and communication systems utilizing check codes, such as low-density parity-check codes (LDPC codes) are described herein. In some examples, check codes described herein utilize a larger number of check operations than check bits.

Abstract: The present disclosure describes systems and methods for the granular, interference aware selection of modulation and coding schemes (MCS) per-sub-band, per-stream, and in some examples, per-user. In some examples, channel condition metrics regarding wireless communication conditions, including interference conditions, from a communication node of a wireless access system may be received. Based at least on the received channel condition metrics indicative of interference, a multidimensional interference margin generator may determine a per-sub-band per-stream margin. A modulation and coding scheme may be selected based on the per-sub-band per-stream margin. In some examples, the selected modulation and coding scheme may be transmitted to various modulators/demodulators, encoders/decoders, and/or other communication nodes within the wireless access system. In some examples, a scheduler may select an allocation based at least on the per-sub-band per-stream margin.

Abstract: Examples described herein include sliding window methods for calculating frequency-localized weights for adaptive beamformers. A window of subcarriers may be used to calculate a cross-correlation vector, inverse covariance matrix, or other components used in a weight calculation for a particular subcarrier. In some examples, a next window of subcarriers may include additional subcarriers, and may not include other subcarriers. The previously-calculated cross-correlation vector, inverse covariance matrix, or other components may be updated in accordance with updates and downdates associated with the added and removed subcarriers. The updated components may be used to generate weights for a subcarrier in the next window.

Abstract: A non-line of sight backhaul system and method are described that provides self-alignment of the antennas beams of the wireless radios of the system, that provides robust operation in licensed and unlicensed frequency bands, that facilitates the use of a reduced number of frequency channels from M to 1 and that enables operation in a non-line of sight (NLOS) propagation environment.

Abstract: Systems and methods are described for performing interference-resistant calibration and compensation of radio-frequency (RF) and analog front-end electronics of antenna-array based receivers during active operation. Examples of systems and methods are described herein that may provide interference-resistant calibration maintenance and ongoing compensation for changing gain and phase in receiver front-end electronic components, due to manufacturing tolerances and operational and environmental factors such as variations in temperature, humidity, supply voltage, component aging, connector oxidation, mechanical stresses and vibration, and/or maintenance operations such as sparing and swapping of cables, front-end electronics modules, and/or associated circuitry.

Abstract: The present disclosure describes systems and methods for selecting modulation and coding schemes (MCS) per-sub-band, and in some examples, per-stream. In some examples, channel condition metrics regarding wireless communication conditions from a communication node of a wireless access system may be received. Based at least on the received channel condition metrics, a modulation and coding scheme may be selected. In some examples, the selected modulation and coding scheme may be transmitted to various modulators/demodulators, encoders/decoders, and/or other communication nodes within the wireless access system.

Abstract: Physical layer processing methods for network acquisition by remote nodes in wireless communication systems are described herein. New methods for wireless network discovery and synchronization by remote nodes are described herein that utilize spatial (e.g., antenna array) processing algorithms which may achieve enhanced functioning in challenging radio frequency environments, such as those containing interference and multipath distortion effects. These methods may include advantageous use of spatial whiteners and associated pluralities of adaptive beamformers to detect network reference and synchronization signals and estimate their parameters.

Abstract: A system and method for precision array processing using semi-coherent transceivers are disclosed.

Abstract: A distributed capacity base station system and method are disclosed. The system may provide a cost effective, high capacity broadband wireless access solution that can co-exist with GPS without interference to the GPS system.

Abstract: Examples described herein include examples of wireless communication devices, systems, and methods which may employ multicarrier frequency division duplexing (multicarrier-FDD) techniques. Such techniques may enhance capacity and/or latency of example beamforming and MIMO systems. In some examples, the techniques described herein may be particularly advantageous in fast changing channels. Example channel duplexing techniques and methods described herein may achieve more efficient handling of fast fading channels by space-time adaptive (STAP) and/or adaptive array systems.

Abstract: A wireless communication network and wireless communication method are disclosed. The network has a plurality of transceivers forming a wireless communication network in which the plurality of transceivers include one or more central nodes and each end node capable of connecting to the one or more central nodes and forming a link. At least some of the transceivers of the network having a plurality of antennas and an array processing element coupled to the plurality of antennas and at least some of the transceivers are housed in an aerial communication node that may be a mini-satellite, a balloon or a drone.

Abstract: Examples described herein include recursive techniques for calculating frequency-localized weights for adaptive beamformers. Components of solutions for other subcarriers are weighted and used to calculate weights for a particular subcarrier. For example, a previously-calculated cross-correlation vector and/or inverse covariance matrix from another subcarrier may be updated for use in calculating weights for a subsequent subcarrier. In some examples, the previously-calculated components are weighted by a forgetting factor. The previously-calculated components themselves may have weighted contributions from yet previously-calculated components.

Abstract: Physical layer processing methods for network acquisition by remote nodes in wireless communication systems are described herein. New methods for wireless network discovery and synchronization by remote nodes are described herein that utilize spatial (e.g., antenna array) processing algorithms which may achieve enhanced functioning in challenging radio frequency environments, such as those containing interference and multipath distortion effects. These methods may include advantageous use of spatial whiteners and associated pluralities of adaptive beamformers to detect network reference and synchronization signals and estimate their parameters.

Abstract: Examples described herein include Weighted Overlap Beamform and Add techniques for calculating frequency-localized weights for adaptive beamformers. Intermediate weights are calculated for overlapping subbands (e.g., using a least-squares solution or a windowed least-squares solution). Each set of intermediate weights may be multiplied by an overlap factor, and combined to provide final weights for a subcarrier.

Abstract: A wireless communication network and wireless communication method are disclosed. The network has a plurality of transceivers forming a wireless communication network in which the plurality of transceivers include one or more central nodes and each end node capable of connecting to the one or more central nodes and forming a link. At least some of the transceivers of the network having a plurality of antennas and an array processing element coupled to the plurality of antennas and at least some of the transceivers are housed in an aerial communication node that may be a mini-satellite, a balloon or a drone.

Abstract: Examples described herein include sliding window methods for calculating frequency-localized weights for adaptive beamformers. A window of subcarriers may be used to calculate a cross-correlation vector, inverse covariance matrix, or other components used in a weight calculation for a particular subcarrier. In some examples, a next window of subcarriers may include additional subcarriers, and may not include other subcarriers. The previously-calculated cross-correlation vector, inverse covariance matrix, or other components may be updated in accordance with updates and downdates associated with the added and removed subcarriers. The updated components may be used to generate weights for a subcarrier in the next window.

Abstract: Examples of wireless OFDM communication systems are described herein which replace pilot subcarriers having known modulation with lower dual subcarriers. At the transmitter, for each resource block, the bits that modulate a few payload subcarriers are selected and then encoded with a short dual code thereby forming dual systematic bits and dual check bits. Such selected payload subcarriers are designated as upper dual subcarriers and the dual check bits modulate the lower dual subcarriers, At the receiver, for each resource block, the dual subcarriers are phase adjusted, demodulated, decoded using the short dual code, and re-modulated thereby forming the original dual subcarrier modulation without phase noise nor channel impairments. The re-modulated dual subcarriers are compared against the received dual subcarriers for channel estimation or carrier phase-locked-loop purposes.

Abstract: Examples of check codes, methods of creating check codes, and communication systems utilizing check codes, such as low-density parity-check codes (LDPC codes) are described herein. In some examples, check codes described herein utilize a larger number of check operations than check bits.

Abstract: A wireless communications system that uses adaptive arrays is disclosed in which the capacity is optimized. A method for optimizing the capacity of a wireless communications system that uses adaptive arrays is also disclosed. The wireless communication system may be a point to multi-point (P2MP) and/or a multi-point to multi-point (MP2MP) STAP system.

Abstract: Systems and methods are described for performing interference-resistant calibration and compensation of radio-frequency (RF) and analog front-end electronics of antenna-array based receivers during active operation. Examples of systems and methods are described herein that may provide interference-resistant calibration maintenance and ongoing compensation for changing gain and phase in receiver front-end electronic components, due to manufacturing tolerances and operational and environmental factors such as variations in temperature, humidity, supply voltage, component aging, connector oxidation, mechanical stresses and vibration, and/or maintenance operations such as sparing and swapping of cables, front-end electronics modules, and/or associated circuitry.