Abstract: A navigation processing system includes at least one processor configured to execute operational instructions that cause the at least one processor to perform operations that include generating navigation data. A data stream is generated based on the navigation data and a data channel spreading sequence. A pilot stream is generated based on a pilot channel spreading sequence. A navigation signal is generated based on applying a bandwidth-efficient modulation scheme to the data stream and the pilot stream. The navigation is signal is broadcast via a navigation signal transmitter for receipt by at least one client device.

Abstract: A methods and apparatuses for providing and configuring channel state information (CSI) reports. A method of operating a user equipment includes receiving a channel state information reference signal (CSI-RS) and generating, based on the CSI-RS reception, a first CSI report and a second CSI report. The first CSI report includes a first channel quality indicator (CQI) index from a first set of CQI indexes and the second CSI report includes a second CQI index from a second set of CQI indexes. The method further includes transmitting the first CSI report in a first channel and the second CSI report in a second channel.

Abstract: An access point (AP) that supports the IEEE 802.11ba protocol may transmit a frame including a physical layer (PHY) preamble to one or more stations (STAs) over a channel. The PHY preamble may include a plurality of repeated modulated legacy signal (L-SIG) fields to spoof a recipient of the frame and protect a wake up signal (WUS) to be subsequently transmitted by the AP. The AP may transmit the WUS to at least a first STA of the one or more STAs, wherein the at least the first STA is a IEEE 802.11ba compliant STA.

Abstract: An operation method of a receiver, which includes setting a coefficient of an equalizer based on one of a plurality of first codes, setting a coefficient of an amplifier based on one of a plurality of second codes, performing offset calibration by driving the equalizer and the amplifier based on the coefficient of the equalizer and the coefficient of the amplifier, storing an offset code corresponding to a voltage offset generated when the equalizer and the amplifier are driven, determining whether the offset calibration is completed, performing a normal operation of obtaining reception data from an input signal, in response to determining that the offset calibration is completed, and removing the voltage offset based on the offset code, in the normal operation.

Abstract: Methods and apparatus for preamble detection in a communication network are disclosed. In an exemplary embodiment, a method includes retrieving parameters from a parameter database, filling a buffer of preamble data received in an uplink transmission from user equipment, and frequency shifting the buffer of preamble data based on one or more first parameters to generate frequency shifted data. The method also includes oversampling the frequency shifted data to generates oversampled data, downsampling the over sampled data based on one or more second parameters to generate preamble samples, and updating the parameter database with updated values for the one or more first and second parameters. The method also includes repeating all the operations until a selected amount of preamble samples is obtained.

Abstract: A wireless station includes at least one oscillator to output a reference signal, and an error calculator to calculate a frequency of the reference signal and calculate a frequency error by subtracting a target frequency of the reference signal from the calculated frequency of the reference signal. The wireless station further includes a modulation data generator to generate modulation data by adding a correction value, varying in negative correlation with the frequency error calculated by the error calculator, to data to be transmitted, and a modulator to conduct frequency modulation on the basis of the modulation data and the reference signal.

Abstract: A beam allocation method and apparatus, relating to the field of communications. The method includes: determining a first network device set, where the first network device set includes to-be-scheduled first network devices; allocating transceivers in a second network device to n first network devices in the first network device set, where n?2; and respectively allocating n beams in different directions simultaneously generated by the transceiver to the n first network devices, where the n first network devices occupy different subbands in a frequency band corresponding to the beams. In this application, coverage of a beam during an instance during scheduling may be expanded. In addition, users may simultaneously transmit data, and there is no waiting latency.

Abstract: A methods and apparatuses for providing and configuring channel state information (CSI) reports. A method of operating a user equipment includes receiving a channel state information reference signal (CSI-RS) and generating, based on the CSI-RS reception, a first CSI report and a second CSI report. The first CSI report includes a first channel quality indicator (CQI) index from a first set of CQI indexes and the second CSI report includes a second CQI index from a second set of CQI indexes. The method further includes transmitting the first CSI report in a first channel and the second CSI report in a second channel.

Abstract: A signal analysis method for analyzing a pulse modulated input signal is described. The signal analysis method includes: receiving the pulse modulated input signal, the input signal including a symbol sequence; recovering a clock signal from the input signal, the clock signal being associated with the input signal; sampling the input signal based on the clock signal, thereby obtaining a set of input signal samples, each of the input signal samples having a certain level being constant over time; determining at least two different levels of input signal samples being associated with different symbols of the symbol sequence; and determining at least one decision threshold based on the at least two different levels determined previously, the decision threshold being associated with a symbol transition of the symbol sequence. Further, a signal analysis apparatus is described.

Abstract: The present disclosure includes a time-to-digital converter (TDC) based RF-to-digital (RDC) data converter for time domain signal processing polar receivers. Polar data conversion achieves better SNR tolerance owing to its phase convergence near the origin in a polar coordinate. The proposed RDC consists of a TDC for phase detection and an analog-to-digital converter (ADC) for amplitude conversion. Unlike the conversional data converter, the proposed ADC's sampling position is guided by the detected phase result from the TDC's output. This TDC assisted data-converter architecture reduces the number of bits required for the ADC. In addition, oversampling is no longer needed. With precisely controlled tunable delay cells and gain compensator, this hybrid data convertor is capable to directly convert Quadrature Amplitude Modulation (QAM) waveforms and Amplitude Phase Shift Keying (APSK) waveforms directly from the RF signal without down-conversion.

Abstract: Methods and systems are described for generating two comparator outputs by comparing a received signal to a first threshold and a second threshold according to a sampling clock, the first and second thresholds determined by an estimated amount of inter-symbol interference on a multi-wire bus, selecting one of the two comparator outputs as a data decision, the selection based on at least one prior data decision, and selecting one of the two comparator outputs as a phase-error decision, the phase error decision selected in response to identification of a predetermined data decision pattern.

Abstract: A wireless communication system includes a first wireless communication node for transmitting a data signal that is sent to a second wireless communication node by skywave propagation over at least two different data transmission paths. The first data transmission path includes at least one reflection point where the data signal is reflected by the atmosphere and the second data transmission path includes more reflection points than the first data transmission path. The data signal that travelled along the first data transmission path is decoded before the data signal that travelled along the second data transmission path.

Abstract: System for adjusting a reference constellation for demodulating an optical signal include a coherent electro-optical receiver configured to convert a received optical signal to a plurality of electrical signals, an array of analog-to-digital convertors configured to digitize the plurality of electrical signals, and processor logic. The processor logic is configured to process the digitized plurality of electrical signals using a reference constellation to yield a plurality of decoded signals and a signal quality measurement. The reference constellation includes an inphase component equal to an ideal inphase component plus an inphase offset and a quadrature component equal to an ideal quadrature component plus a quadrature offset. The processor logic is configured to determine an optimal inphase offset and optimal quadrature offset. The processor logic is configured to update the reference constellation using the optimal inphase offset and the optimal quadrature offset.

Abstract: Ethernet link extension methods and devices provide, in one illustrative embodiment, an Ethernet link extender with physical medium attachment (PMA) circuits each having a transmitter and receiver that communicate with a respective node in a sequence of communication phases. The sequence includes at least an auto-negotiation phase and a subsequent training phase, the phases occurring simultaneously for both PMA circuits. In the auto-negotiation phase, the PMA circuits operate in a pass-through mode, rendering the extender transparent to the two nodes. In the training phase, the PMA circuits operate independently, sending training frames to their respective nodes based in part on received back-channel information and locally-determined training status information. The training phases may be prolonged if needed to provide a simultaneous transition to a frame-forwarding phase of the sequence.

Abstract: Systems and methods for classifying a P25 Phase 1 downlink transmission as using either C4FM modulation or CQPSK modulation are provided. Some methods can include calculating a first signal-to-noise ratio (SNR) at or near a middle of a first symbol of a received wireless signal, calculating a second SNR at or near an edge of the first symbol, calculating a difference between the second SNR and the first SNR, determining whether the difference is greater than a threshold, and classifying a modulation technique of the received wireless signal as either C4FM modulation or CQPSK modulation based on whether the difference is greater than the threshold.

Abstract: A data transmission link includes a transmitter superpositioning a data signal and a clock signal to generate a first signal. The transmitter transmits the first signal, through a link, wherein, the clock signal has a frequency equal to or higher than a Nyquist frequency of the data signal.

Abstract: Pilot tones are included within symbols (e.g., orthogonal frequency division multiplexing (OFDM) symbols) transmitted between wireless communication devices. The pilot tones occupy fewer than all tone locations in any given symbol, and the pilot tones occupy different respective locations within different symbols. Generally, these traveling pilots are assigned to different respective tone locations in different symbols. In total, the pilot tones did not cover every single tone location within the symbols used to convey information between devices. Considering for example, when pilots occupy fewer than all tone locations, even among multiple symbols, a device may perform interpolation to generate a pilot tone estimate corresponding to a tone location not occupied by pilot tone within any symbol. Also, power or magnitude of the pilot tones themselves may be boosted or amplified relative to power magnitude of other tones within such symbols.

Abstract: Methods and systems to extract a spectrum of a hyperspectral interferogram, with innovative treatment of off-axis spectral correction and other features, which may be efficiently performed on-board a satellite.

Abstract: Accordingly, systems and methods for managing power when the number of training and data tones are increased in a wireless communications system are provided. An L-SIG field is generated that includes a set of data and pilot tones, wherein the pilot tones are inserted between the data tones in the set of data and pilot tones. A plurality of training tones is added to the L-SIG field before and after the set of data and pilot tones. A symbol is generated that includes the L-SIG field, an L-LTF field, and a data field, wherein the training tones of the L-SIG field provide channel estimates for the data field. Power of the L-LTF field is managed relative to power of the L-SIG field in the generated symbol in a time domain.

Abstract: A wireless microphone and/or in-ear monitoring system having at least one first mobile device for wirelessly transmitting first audio signals. The system also has at least one base station for wirelessly receiving the first audio signals transmitted by the mobile device. The wireless transmission is based on an orthogonal frequency-division multiplexing transmission (OFDM) during a time-division multiple access (TDMA) time slot. Each wireless microphone occupies at least one slot within 2 ms. Each of the TDMA frames has a plurality of slots which respectively have precisely one OFDM symbol. Accordingly, precisely one OFDM symbol is transmitted in each TDMA slot. During a time slot made available in accordance with the TDMA, a transmission is effected on the basis of an OFDM method. The TDMA frame length is so short as a latency of <4 ms is required for professional audio transmission, for example in the case of wireless microphone systems.

Abstract: An appropriate synthesized signal cannot be obtained by only correcting relative phase errors of a plurality of received signals; therefore, a received signal processor according to an exemplary aspect of the present invention includes a plurality of signal-to-noise ratio estimation means for estimating respective signal-to-noise ratios of a plurality of digital signal sequences in which relative phase errors of a plurality of received signal sequences having been corrected; a plurality of temporary decision means for performing symbol decisions of the plurality of digital signal sequences and outputting symbol signal sequences; symbol-map-rotation determination means for determining respective phase rotation amounts of the plurality of digital signal sequences from the plurality of symbol signal sequences and the respective signal-to-noise ratios of the plurality of digital signal sequences; and a plurality of phase rotation means for rotating phases of the plurality of digital signal sequences respectively

Abstract: System for adjusting a reference constellation for demodulating an optical signal include a coherent electro-optical receiver configured to convert a received optical signal to a plurality of electrical signals, an array of analog-to-digital convertors configured to digitize the plurality of electrical signals, and processor logic. The processor logic is configured to process the digitized plurality of electrical signals using a reference constellation to yield a plurality of decoded signals and a signal quality measurement. The reference constellation includes an inphase component equal to an ideal inphase component plus an inphase offset and a quadrature component equal to an ideal quadrature component plus a quadrature offset. The processor logic is configured to determine an optimal inphase offset and optimal quadrature offset. The processor logic is configured to update the reference constellation using the optimal inphase offset and the optimal quadrature offset.

Abstract: A wireless microphone and/or in-ear monitoring system having at least one first mobile device for wirelessly transmitting first audio signals. The system also has at least one base station for wirelessly receiving the first audio signals transmitted by the mobile device. The wireless transmission is based on an orthogonal frequency-division multiplexing transmission (OFDM) during a time-division multiple access (TDMA) time slot. Each wireless microphone occupies at least one slot within 2 ms. Each of the TDMA frames has a plurality of slots which respectively have precisely one OFDM symbol. Accordingly, precisely one OFDM symbol is transmitted in each TDMA slot. During a time slot made available in accordance with the TDMA, a transmission is effected on the basis of an OFDM method. The TDMA frame length is so short as a latency of <4 ms is required for professional audio transmission, for example in the case of wireless microphone systems.

Abstract: Wideband polar receivers and method of operation are described. A phase-modulated input signal is received at a polar receiver that includes an injection-locked oscillator. The injection-locked oscillator includes a plurality of injection points. Based on the frequency of the input signal, a particular Nth harmonic is selected, and the input signal is injected at the set of injection points corresponding to the selected Nth harmonic. The injection-locked oscillator generates an oscillator output signal, and the phase of the input signal is determined from the phase of the oscillator output signal. In some embodiments, the oscillator output signal is frequency-multiplied by N, mixed with the input signal, and filtered for use in amplitude detection. The input signal is decoded based on the phase and amplitude information.

Abstract: A Mach-Zehnder modulator (MZM) includes a first optical path with a first diode coupled to a first voltage signal node and configured to modify a phase of a first light signal transmitted through the first optical path. A further diode is positioned in the first optical path and configured to introduce a phase shift to the first light signal. A second optical path includes a second diode coupled to a second voltage signal node and configured to modify a phase of a second light signal transmitted through the second optical path. A first voltage signal carried on the first voltage signal node and a second voltage signal carried on the second voltage signal node each vary between a reverse biasing voltage level and a forward biasing voltage level. An optical coupler is coupled to the first and second optical paths.

Abstract: An apparatus includes a radio frequency (RF) receiver having a multi-bit observation interval. The RF receiver includes a Coordinate Rotation Digital Computer (Cordic) circuit to receive a complex signal derived from RF signals and to generate a phase signal. The RF receiver further includes a timing correlator and frequency offset estimator coupled to receive data derived from a frequency signal derived from the phase signal. The RF receiver in addition includes a Viterbi decoder coupled to provide decoded data derived from the frequency signal.

Abstract: A wireless transmitter, comprises a frame generator configured to generate a frame by including an auxiliary preamble, an auxiliary syncword, a guard, a preamble, an address, a packet control, a payload and a CRC; a modulator communicatively coupled to the frame generator and configured to modulate the frame according to a variable transmission rate and include the transmission rate in the auxiliary syncword; and a RF front end communicatively coupled to the modulator and configured to transmit the modulated signal to a receiver.

Abstract: Aspects of this disclosure relate to systems and methods of performing dynamic impedance tuning. Certain aspects may be performed by or include a dynamic impedance matching network. The dynamic impedance matching network can determine a desired output power for a power amplifier, true power information for the power amplifier, and an output power delivered to a load by the power amplifier. In addition, the dynamic impedance matching network can determine whether the output power satisfies the true power information. Responsive to this determination, the dynamic impedance matching network may modify a load line impedance for the power amplifier using an impedance tuning network.

Abstract: A decoder includes circuitry and a soft decoder. The circuitry is configured to receive channel hard decisions for respective bits of a Generalized Low-Density Parity Check (GLDPC) code word that includes multiple component code words, including first and second component code words having one or more shared bits, to schedule decoding of the GLDPC code word, and following the decoding, to output the decoded GLDPC code word. The soft decoder is configured to receive the channel hard decisions corresponding to the first component code word, to further receive soft reliability measures that were assigned to the shared bits in decoding the second component code word, and to decode the first component code word based on the channel hard decisions and the soft reliability measures.

Abstract: An apparatus for decoding a data modulated signal includes a signal receiver that receives a data modulated signal that is encoded with phase-shift keying (PSK) and provides an amplified signal corresponding to the data modulated signal, a tunable phase shifter that receives a local reference signal and a selected phase shift, applies the selected phase shift to the local reference signal to produce a phase shifted reference signal, a summing unit that sums the amplified signal and the phase shifted reference signal to produce a summed signal, an amplitude detector that determines an amplitude of the summed signal, and a symbol detector that varies the selected phase shift and determines a current symbol within the data modulated signal based on the amplitude of the summed signal as the selected phase shift is varied. A corresponding method is also disclosed herein.

Abstract: Systems and methods for managing control signaling overhead for a multi-carrier HSDPA (MC-HSDPA) may be disclosed. In particular, a plurality of downlink carriers may be received and bundled or paired. Configuration information indicative of the bundling may then be generated and transmitted. Additionally, one or more components such as antennas, user equipment (UE), and the like may receive an indication of a configuration or state via a high speed shared control channel (HS-SCCH) order where the indication includes order bits and order types and the configuration may be applied to activate and/or deactivate the components or operations such as uplink closed-loop transmit diversity (CLTD), uplink multiple-input multiple-output (MIMO). The order bits and/or order types may also be extended to support the activation/deactivation of additional carriers of MC-HSDPA.

Abstract: An audio signal processing apparatus that includes a band division section, an analysis section, a gain adjustment amount calculation section, and a gain adjustment section. The band division section is configured to generate a resonance in-band signal by band division on an audio input signal. The analysis section is configured to extract an amount of features from each of the resonance in-band signal and the input signal. The gain adjustment amount calculation section is configured to calculate a gain adjustment amount for a resonance frequency band in the input signal, the gain adjustment amount being calculated based on the amount of features of the resonance in-band signal and the amount of features of the input signal. The gain adjustment section is configured to perform a gain adjustment on the resonance frequency band in the input signal based on the gain adjustment amount.

Abstract: A least squares estimator of carrier phase and amplitude in a receiver in a communication system using a phase shift keying modulation scheme that uses both known pilot symbols and unknown data symbols is described. That is, the method exploits knowledge of pilot symbols in addition to the unknown data symbols to estimate carrier phase and amplitude. Further, an efficient recursion based estimation method is described that only requires O(L. log L) arithmetic operations where L is the number of received signals. This method uses the M-Ary rounded phase offsets to sort the data symbols and this sorted order is used to recursively calculate candidate values in an optimization process. Simulation results show that the estimation methods Using data and pilot symbols outperform estimation methods using only data symbols (ie non-coherent detection methods). Further, the system can be used for systems using multiple M-ary phase shift keying digital modulation schemes.

Abstract: A device is configured to transmit uplink data to a base station using a resource. The device may receive an acknowledgment from the base station based on the uplink data. The acknowledgment may indicate a positive acknowledgment or a negative acknowledgment. The device may decode the acknowledgment as the positive acknowledgment or the negative acknowledgment. The device may receive a control message from the base station indicating resource assignments for user devices. The device may determine the acknowledgement is falsely decoded as the positive acknowledgment or the negative acknowledgment based on the resource assignments. The device may selectively retransmit the uplink data to the base station using the resource based on whether the acknowledgment is falsely decoded as the positive acknowledgment or the negative acknowledgment.

Abstract: The present disclosure relates to a timing synchronization circuit for a digital receiver structure that includes a timing error detection module comprising a phase difference calculation unit arranged for calculating a phase difference between incoming samples of a digital data stream, and a timing error estimator arranged for determining a timing error estimate based on the calculated phase difference, and for generating, based on the determined timing error estimate, a signal indicative of timing error detection. The circuit also includes a timing error control module arranged for receiving the signal indicative of timing error detection, for evaluating the number of received signals indicative of timing error detection and for outputting, after comparison with a threshold value, a sampling adjustment command for adjusting the sampling instants applied for obtaining the digital data stream.

Abstract: Systems and methods for managing control signaling overhead for a multi-carrier HSDPA (MC-HSDPA) may be disclosed. In particular, a plurality of downlink carriers may be received and bundled or paired. Configuration information indicative of the bundling may then be generated and transmitted. Additionally, one or more components such as antennas, user equipment (UE), and the like may receive an indication of a configuration or state via a high speed shared control channel (HS-SCCH) order where the indication includes order bits and order types and the configuration may be applied to activate and/or deactivate the components or operations such as uplink closed-loop transmit diversity (CLTD), uplink multiple-input multiple-output (MIMO). The order bits and/or order types may also be extended to support the activation/deactivation of additional carriers of MC-HSDPA.

Abstract: Logic may calculate predicted phase rotations based upon more than one previously determined phase rotation. Logic may access memory to store and retrieve previously determined phase rotations to calculate predicted phase rotations. Logic may determine channel information updates such as channel state information and phase correction information from pilot tones that do not travel close to the direct current (DC) tone or the band edge (or guard) tones and replace the missing phase rotations with predicted phase rotations. Logic may skip phase tracking from pilot tones that have traveled close to the DC tone or the edge tones or that experience channel fading, which may result in a predicted phase rotation being more accurate than a phase rotation determined by processing the corresponding pilot tone.

Abstract: An audio signal processing device 100 includes a period detecting unit 102 for detecting the fundamental period of an input audio signal 101; a square wave generating unit 106 for generating, according to the fundamental period the period detecting unit 102 detects, a square wave 107 whose period is an integer multiple of the fundamental period; an amplitude correction coefficient generating unit 103 for calculating an amplitude correction coefficient 109 approximately equal and proportional to the intensity of the input audio signal 101; a first multiplier 108 for generating an amplitude-corrected square wave 110 by multiplying the square wave 107 by the amplitude correction coefficient 109; and an adder 104 for adding the amplitude-corrected square wave 110 to the input audio signal 101.

Abstract: Various aspects of the disclosure are directed to methods, systems, and apparatus, including computer programs encoded on a computer storage medium, for identifying network events. In one aspect, a method includes monitoring signal characteristic values for signals transmitted over a communications channel of a power line communications system and determining that a signal level value for the channel is less than a threshold signal level value for the channel. In response to determining that the signal level value for the channel is less than the threshold signal level value for the channel, a signal to noise ratio for the communications channel is computer and it is determined that the signal to noise ratio for the channel exceeds a threshold value. In response to determining that the signal to noise ratio for the communications channel exceeds the threshold value, storing data received over the communications channel is stored as valid data.

Abstract: A charge pump circuit for an optical phase lock loop, which includes first and second optical thyristors configured to receive respective first and second digital optical signal inputs. A first control circuit receives a first digital electrical signal input corresponding to the second digital optical signal input, and a second control circuit receives a second digital electrical signal input corresponding to the first digital optical signal input. The first control circuitry controls switching operation of the first optical thyristor that sources current to a first filter circuit in response to the levels of the first digital optical signal input and the first digital electrical signal input. The second control circuitry control switching operation of the second optical thyristor that sinks current from a second filter circuit in response to the levels of the second digital optical signal input and the second digital electrical signal input.

Abstract: A transmission point device, user equipment, and method of reporting phase offsets between signals received from a serving cell and neighbor cells in a communication system are disclosed. The method comprises steps of: quantizing the phase offsets using a predetermined number of bits; utilizing another bit to indicate constellation of the phase offsets; reporting the quantized phase offsets and the constellation to transmission point. The present disclosure may improve the signal combining gain from multiple transmission points with minimum overhead increasing.

Abstract: Embodiments of the invention provide a method, distributed antenna system, and components that generate a jitter reduced clock signal from a binary encoded data stream transmitted over a communication medium. The method includes receiving a modulated signal that includes the binary encoded data stream and generating a recovered clock signal that is phase locked to the binary encoded data stream. The method further comprises generating a stable recovered clock signal by filtering the recovered clock signal to remove jitter, while allowing the clock signal to track long-term drift.

Abstract: A wireless communication device for a CDMA system is configured to generate power estimates with reduced estimation bias. The power estimates may be used for delay estimation, MMSE channel estimation, demodulation, or other purposes. The wireless communication device produces first set of power estimates for a first set of delays and generates a model of the signal powers at the first set of delays as a function of the power leakage from non-aligned signal images in the received signal into the first set of delays. The wireless communication device then computes a second set of power estimates with reduced estimation bias based on the first set of power estimates and the model of the signal powers.

Abstract: Systems and methods are provided for fast and precise estimation of frequency with relatively minimal sampling and relatively high tolerance to noise.

Abstract: A power line communication system is provided in which the influence of the impulsive noise unexpectedly generated on a power line which is a communication medium can be reduced according to the characteristics of the impulsive noise by an existing method and power line communication can be realized without a hindrance. A transmitter is constituted by: a modulator for conveying a LIN data signal by a power line; a filter that allows a signal of a predetermined band to pass therethrough; and a sinusoidal wave outputter (sinusoidal wave in the figure). In contrast, the receiver is constituted by the sinusoidal wave outputter, the filter and a demodulator that performs demodulation. To the power line, a limiter that limits the amplitude of the propagating signal to a predetermined amplitude (reception signal amplitude) is connected.

Abstract: A precoding codebook matrix/vector of length 2L is generated by the selection of two matrices/vectors, each from one of a predetermined set of L×L matrices and multiplying each column of one of the matrices/vectors by a complex coefficient.

Abstract: A method for optimizing a constellation for M-ary amplitude phase shift keying (M-APSK) that provides signal modulation for transmitting a series of digital bits in an analog signal by a transmitter to be received by a receiver over a communications channel. The method includes identifying symbol-wise mutual information of a transmitted constellation, where the symbol-wise mutual information includes a conditional probability density function. The method identifies an unconstrained capacity that defines an ultimate performance limit of the constellation, and minimizes a difference between a rate of the symbol-wise mutual information and a rate of the unconstrained capacity to determine the number of rings, the number of symbols in each ring and the ring ratio in the constellation.

Abstract: Techniques are provided for detecting a coded signal in the presence of non-Gaussian interference. In an embodiment, a primary transmitter corresponds to a desired transmitter, and one or more secondary transmitters correspond to interfering transmitters. In an embodiment, received symbols, which include non-Gaussian interference and additive noise, are decoded to determine a set of message bits. In an embodiment, an estimate of the set of message bits may be determined using a minimum-distance detector or an optimal-ML detector, for example, depending on the signal-to-noise and/or signal-to-interference ratios at a receiver.

Abstract: In a phased-array communications system with a distributed processing architecture, channelized beamforming is used to minimize sampling and computational requirements, as well as reduce the data rates required for the communication of data and control information between system components. A central processor within the phased array system performs parallelized synthesis of channelized beams to form beams composite beams in sub-bands that overlap multiple channels. The phased array system incorporates a flexible scheme for channelization, channelized beamforming, and synthesis so that any number of composite beams may be synthesized in parallel at any one time. The system is capable of simultaneously processing beams that occupy overlapping subbands, and does not require restriction on the bandwidths or center frequencies of the subbands which the beams occupy.

Abstract: Access terminals are adapted to facilitate estimation of signal-to-noise ratios for received wireless transmissions. According to at least one example, a wireless communication device can receive a plurality of data symbols. The wireless communication device can determine a first estimate of a signal-to-noise ratio based on first estimates of a signal power and a noise power associated with the plurality of received data symbols. When the first estimate of the signal-to-noise ratio is below a predetermined threshold, a second estimate of the signal-to-noise ratio can be determined based on second estimates of the signal power and the noise power for the received data symbols. Other aspects, embodiments, and features are also included.