Abstract: A method of signal demodulation includes receiving, by a signal receiver, a first signal modulated by a symbol corresponding to a point in a constellation; generating, by the signal receiver and on the basis of the first signal, a modulation estimate; identifying, by the signal receiver and on the basis of the modulation estimate, a row or column of a candidate lookup table, the row or column corresponding to a region of the constellation; reading, by the signal receiver, from the row or column of the candidate lookup table one or more candidate points of the constellation, at least one among the one or more candidate points being more distant, from a center of the region, than a point, in the constellation, not among the one or more candidate points, and demodulating, by the signal receiver and on the basis of the one or more candidate points, the first signal.

Abstract: A method and system are herein disclosed. The method includes receiving sounding reference signals (SRS) at a massive multiple-input multiple-output (MIMO) base station (BS) from a user equipment (UE), determining, at the BS, beamformers for known channels of the SRS, determining, at the BS, beamformers for unknown channels of the SRS based on the determined beamformers for the known channels, and selecting a modulation and coding scheme (MCS) based on the determined beamformers.

Abstract: A method of signal demodulation includes receiving, by a signal receiver, a first signal modulated by a symbol corresponding to a point in a constellation; generating, by the signal receiver and on the basis of the first signal, a first initial modulation estimate; identifying, by the signal receiver and on the basis of the first initial modulation estimate, a row or column of an initial candidate lookup table, the row or column corresponding to a region of the constellation; reading, by the signal receiver, from the row or column of the initial candidate lookup table one or more first initial candidate points of the constellation, at least one among the one or more first initial candidate points being more distant, from a center of the region, than a point, in the constellation, not among the one or more first initial candidate points, and demodulating, by the signal receiver and on the basis of the one or more first initial candidate points, the first signal.

Abstract: A system and method for receiving a quadrature amplitude modulation symbol. In some embodiments, the symbol has a plurality of bits and is associated with a point in a constellation of quadrature amplitude modulation points, each point of the constellation having associated with it a binary word. The method includes receiving a first analog signal carrying a modulation; performing initial estimation, to generate a first initial modulation estimate, for a portion of the first analog signal carrying a modulation; identifying, based on the first initial modulation estimate, a row of an initial candidate lookup table, the row corresponding to a region of the constellation; and reading from the row of the initial candidate lookup table a first plurality of initial candidate points of the constellation.

Abstract: A system and method for blind detection of preempted resources in an orthogonal frequency division multiplexing (OFDM) system is herein disclosed. According to one embodiment, a method for blind detection of resources in an eMBB pre-empted by a URLLC includes receiving soft information including at least one code block, attempting to decode the at least one code block, and running URLLC blind detection on the at least one code block with the decoding attempt fails.

Abstract: A method and system are herein disclosed. The method includes receiving sounding reference signals (SRS) at a massive multiple-input multiple-output (MIMO) base station (BS) from a user equipment (UE), determining, at the BS, beamformers for known channels of the SRS, determining, at the BS, beamformers for unknown channels of the SRS based on the determined beamformers for the known channels, and selecting a modulation and coding scheme (MCS) based on the determined beamformers.

Abstract: A system and method for receiving a quadrature amplitude modulation symbol. In some embodiments, the symbol has a plurality of bits and is associated with a point in a constellation of quadrature amplitude modulation points, each point of the constellation having associated with it a binary word. The method includes receiving a first analog signal carrying a modulation; performing initial estimation, to generate a first initial modulation estimate, for a portion of the first analog signal carrying a modulation; identifying, based on the first initial modulation estimate, a row of an initial candidate lookup table, the row corresponding to a region of the constellation; and reading from the row of the initial candidate lookup table a first plurality of initial candidate points of the constellation.

Abstract: A system and method for blind detection of preempted resources in an orthogonal frequency division multiplexing (OFDM) system is herein disclosed. According to one embodiment, a method for blind detection of resources in an eMBB pre-empted by a URLLC includes receiving soft information including at least one code block, attempting to decode the at least one code block, and running URLLC blind detection on the at least one code block with the decoding attempt fails.

Abstract: A receiver of a modulated signal is presented. The receiver includes a synchronization detector configured to receive a signal indicative of the modulated signal that includes a synchronization header and a data payload, and to detect an end of the synchronization header. The synchronization detector is configured to generate a differential signal based on the signal, perform cross-correlation of the differential signal with a reference differential signal to generate a cross-correlation output, compare a first sample of the cross-correlation output at a sample index associated with a hypothesized start frame delimiter (SFD) peak index with a second sample of the cross-correlation output at a sample index associated with a hypothesized preamble peak index, and detect an end of the synchronization header in response to a comparison result in which a magnitude of the first sample is greater than a magnitude of the second sample of the cross-correlation output.

Abstract: A system and method for removing bias from a frequency estimate. A simulation is used to predict, for various values of the signal to noise ratio, a bias in a raw frequency estimate produced by a frequency estimation algorithm. A straight line is fit to simulated frequency offset estimates as a function of true frequency offset, and the reciprocal of the slope of the line is stored, as a multiplicative bias removal term, in a lookup table, for the simulated signal to noise ratio. In operation, the raw frequency estimate is multiplied by a multiplicative bias removal term, obtained from the lookup table, to form a corrected frequency offset estimate.

Abstract: According to an embodiment of the present disclosure, a receiver of modulated signals comprises a signal mixer, a synchronization detector, and a data demodulator. The signal mixer is configured to perform baseband down-conversion of a signal according to a mixer frequency, the signal including a synchronization header and a data payload. The synchronization detector is configured to: generate a differential signal based on the signal, perform cross-correlation of the differential signal with a reference differential signal to generate a cross-correlation output, and analyze the cross-correlation output to detect an end of the synchronization header. The data demodulator is configured to demodulate the data payload in response to detection of the end of the synchronization header.

Abstract: A receiver of a modulated signal includes a synchronization detector configured to receive a signal indicative of the modulated signal and to detect an end of the synchronization header in the signal. The synchronization detector is configured to generate a differential signal based on the signal, perform cross-correlation of the differential signal with a reference differential signal to generate a cross-correlation output, compare a first sample of the cross-correlation output at a sample index associated with a hypothesized start frame delimiter (SFD) peak index with a second sample of the cross-correlation output at a sample index associated with a hypothesized preamble peak index, and detect an end of the synchronization header in response to a comparison result in which a magnitude of the first sample of the cross-correlation output is greater than a magnitude of the second sample of the cross-correlation output.

Abstract: According to an embodiment of the present disclosure, a receiver of modulated signals comprises a signal sampling unit configured to sample a signal, a zero-crossing demodulator, and a timing offset tracking unit. The zero-crossing demodulator includes: a zero-crossing counter configured to determine a number of zero crossings for each pulse of the signal, and a symbol selector configured to decode a sequence of pulses as a symbol based on the number of zero crossings in the sequence of pulses. The timing offset tracking unit is configured to: calculate a metric based on an accumulation of the number of zero crossings and corresponding pulse values of the decoded symbol, compare the metric to a predetermined threshold value, and compensate a timing offset of the signal by causing the signal sampling unit to sample the signal at an earlier interval or a later interval in response to the comparison.

Abstract: According to an embodiment of the present disclosure, a receiver of modulated signals comprises a signal sampling unit configured to sample a signal, a zero-crossing demodulator, and a timing offset tracking unit. The zero-crossing demodulator includes: a zero-crossing counter configured to determine a number of zero crossings for each pulse of the signal, and a symbol selector configured to decode a sequence of pulses as a symbol based on the number of zero crossings in the sequence of pulses. The timing offset tracking unit is configured to: calculate a metric based on an accumulation of the number of zero crossings and corresponding pulse values of the decoded symbol, compare the metric to a predetermined threshold value, and compensate a timing offset of the signal by causing the signal sampling unit to sample the signal at an earlier interval or a later interval in response to the comparison.

Abstract: According to an embodiment of the present disclosure, a receiver of modulated signals comprises a signal mixer, a synchronization detector, and a data demodulator. The signal mixer is configured to perform baseband down-conversion of a signal according to a mixer frequency, the signal including a synchronization header and a data payload. The synchronization detector is configured to: generate a differential signal based on the signal, perform cross-correlation of the differential signal with a reference differential signal to generate a cross-correlation output, and analyze the cross-correlation output to detect an end of the synchronization header. The data demodulator is configured to demodulate the data payload in response to detection of the end of the synchronization header.

Abstract: A system and method for removing bias from a frequency estimate. A simulation is used to predict, for various values of the signal to noise ratio, a bias in a raw frequency estimate produced by a frequency estimation algorithm. A straight line is fit to simulated frequency offset estimates as a function of true frequency offset, and the reciprocal of the slope of the line is stored, as a multiplicative bias removal term, in a lookup table, for the simulated signal to noise ratio. In operation, the raw frequency estimate is multiplied by a multiplicative bias removal term, obtained from the lookup table, to form a corrected frequency offset estimate.