Abstract: Techniques are provided for radio frequency (RF) sensing using a single wireless device. An example method for determining a distance to an object with radio frequency sensing includes transmitting a radio frequency signal with a transmit channel on a wireless device, receiving a leakage signal with a receive channel on the wireless device at a first time, such that the leakage signal is based on the radio frequency signal, receiving a reflected signal with the receive channel on the wireless device at a second time, such that the reflected signal is based on the radio frequency signal reflecting from the object, and determining the distance to the object based at least in part on a difference between the first time and the second time.

Abstract: Methods, systems, and devices for wireless communications are described. A device may receive a signal, such as a wideband or narrowband signal, and determine an in-phase and quadrature-phase imbalance of the signal, a phase and amplitude of the signal, a conjugate of the signal, or any combination thereof. Based on the in-phase and quadrature-phase imbalance, the device may determine a kernel set having a set of in-phase and quadrature-phase imbalance correction terms and select an in-phase and quadrature-phase imbalance correction term from the set based on a selection criteria. The device may then apply the in-phase and quadrature-phase imbalance correction term to the signal.

Abstract: A plurality of received signals are received at a first communication device, the plurality of received signals corresponding to at least one training signal having been transmitted by a second communication device a plurality of times via a plurality of antennas by the second communication device applying a respective antenna weight vector from a plurality of different antenna weight vectors each time the at least one training signal is transmitted. The first communication device generates a transmitter antenna weight vector based on a mathematical combination of at least i) the plurality of received signals, ii) the antenna weight vectors applied by the second communication device when transmitting the at least one training signal the plurality of times, and iii) the at least one training signal. The first communication device transmits the transmitter antenna weight vector to the second communication device.

Abstract: Systems and methods are provided for detecting a received synchronization signal. The method includes receiving, at a receiver, a signal from a transmitter and the signal includes the received synchronization signal. The method includes processing the received signal and a plurality of candidate synchronization signals to obtain a plurality of correlation signals. Each candidate synchronization signal is associated with one of the plurality of correlation signals. The method includes selecting, based at least in part on the plurality of correlation signals, one of the plurality of candidate synchronization signals. The selected candidate synchronization signal is correlated with the received synchronization signal. The method includes detecting the received synchronization signal based at least in part on (i) the received signal, and (ii) a characteristic obtained from the correlation signal that is associated with the selected candidate synchronization signal.

Abstract: Systems and methods are provided for detecting a received synchronization signal. The method includes receiving, at a receiver, a signal from a transmitter and the signal includes the received synchronization signal. The method includes processing the received signal and a plurality of candidate synchronization signals to obtain a plurality of correlation signals. Each candidate synchronization signal is associated with one of the plurality of correlation signals. The method includes selecting, based at least in part on the plurality of correlation signals, one of the plurality of candidate synchronization signals. The selected candidate synchronization signal is correlated with the received synchronization signal. The method includes detecting the received synchronization signal based at least in part on (i) the received signal, and (ii) a characteristic obtained from the correlation signal that is associated with the selected candidate synchronization signal.

Abstract: The present disclosure describes systems and techniques relating to wireless communications. According to an aspect of the described systems and techniques, an apparatus includes: circuitry configured to receive wireless communication transmissions having periodic synchronization signals transmitted at a fixed interval, wherein the periodic synchronization signals convey information used to establish communication between wireless communication devices; and circuitry configured to acquire the periodic synchronization signals of the wireless communication transmissions by, at least in part, (i) calculating objective function values for hypotheses of parameter sets for a current period, (ii) combining only a portion of the calculated objective function values with stored objective function value data from a prior period to form combined data used in signal acquisition, and (iii) storing the combined data or the portion of the calculated objective function values for use in a next period.

Abstract: Devices, systems, methods, and other embodiments associated with phase based transformation of repeated signals are described. In one embodiment, an apparatus includes duplication logic configured to duplicate a string of data to form a duplicate string of data. Transformation logic is configured to modify phases associated with the string of data to generate a modified string of data. Signal generation logic is configured to generate a signal for wireless transmission where the signal having at least the modified string of data and the duplicate string of data.

Abstract: Advantage is taken of adaptive allocation techniques by intentionally creating multi-user diversity in an otherwise flat fading environment in order to improve system capacity. In one embodiment, multi-path distortion can be resolved to determine subscriber station (SS) diversity gain. Overall network capacity can be increased by allocating channel assignments to SSs within the network based on determined SS diversity gains. In one embodiment, intentional multi-path distortion is produced by transmitting a signal and a time-delayed version of the signal from a base station (BS).

Abstract: The present disclosure describes techniques for avoiding interference among multiple radios. In some aspects a communication channel of a first wireless interface of a device is determined to be adjacent to a frequency band in which a second wireless interface of the device is configured to communicate and channel measurement results are altered prior to transmission by the first wireless interface to a base station, effective to prevent the base station from selecting, for use by the first wireless interface, the channel adjacent to the frequency band of the second wireless interface.

Abstract: A system including a first power measuring module, a gain control module, and a signal processing module. The first power measuring module is configured to generate a first power measurement of a signal received by a receiver of a wireless device based on a plurality of reference signals received in the signal by the receiver of the wireless device. Each of the plurality of reference signals is transmitted at a predetermined power. The first power measurement is generated in frequency domain. The first power measurement is generated during a first frame of the signal received by the receiver of the wireless device. The gain control module is configured to adjust a gain of the receiver of the wireless device based on the first power measurement. The signal processing module is configured to process a second frame in the signal subsequent to the first frame at the adjusted gain.

Abstract: Systems and methods are provided for detecting a received synchronization signal. The method includes receiving, at a receiver, a signal from a transmitter, where one or more portions of the received signal include the received synchronization signal. The method includes processing the one or more portions of the received signal to obtain a differential signal, and processing the differential signal and a plurality of candidate differential synchronization signals to obtain a plurality of cross-correlation signals. Each candidate differential synchronization signal is associated with one cross-correlation signal.

Abstract: Devices, systems, methods, and other embodiments associated with phase based transformation of repeated signals are described. In one embodiment, an apparatus includes duplication logic configured to duplicate a string of data to form a duplicate string of data. Transformation logic is configured to modify phases associated with the string of data to generate a modified string of data. Signal generation logic is configured to generate a signal for wireless transmission where the signal having at least the modified string of data and the duplicate string of data.

Abstract: A first plurality of training data units are transmitted via a plurality of antennas of a first station as part of a first transmit beamforming training procedure. Subsequently, a second plurality of training data units are received via the plurality of antennas as part of second transmit beamforming procedure while the first station applies a single receive antenna configuration. The second plurality of training data units includes an information element that specifies a feedback from a second station, the feedback including an identifier corresponding to one of the training data units in the first plurality of data units. The first station transmits a feedback message to the second station, that includes (i) one or more indicators of one or more training data units selected from the second plurality of training data units, and (ii) a request to perform a subsequent beamforming training procedure.

Abstract: A method and apparatus for antenna switching, grouping, and channel assignments in wireless communication systems. The invention allows multiuser diversity to be exploited with simple antenna operations, therefore increasing the capacity and performance of wireless communications systems. Channel characteristics indicative of signal reception quality for downlink or bi-directional traffic for each channel/antenna resource combination are measured or estimated at a subscriber. Corresponding channel characteristic information is returned to the base station. Channel characteristics information may also be measured or estimated for uplink or bi-directional signals received at each of multiple receive antenna resources. The base station employs channel allocation logic to assign uplink, downlink and/or bi-directional channels for multiple subscribers based on channel characteristics measured and/or estimated for the uplink, downlink and/or bi-directional channels.

Abstract: A beamforming training (BFT) data unit for transmission via a communication channel in a wireless personal area network is generated, and in particular, is for transmitting beamforming training information. A physical layer header and first BFT data are encoded using block encoding to generate a first block. Second BFT data are encoded using block encoding to generate a second block. The BFT data unit is generated with a fixed-length payload, such that the BFT data unit includes only i) a preamble, ii) the first block, and iii) the second block.

Abstract: In embodiments of frame boundary detection, a data signal that includes a plurality of different synchronization signals is received. Symbol boundaries of orthogonal frequency-division multiplexing (OFDM) symbols are detected in the data signal based on signal characteristics of the OFDM symbols. The characteristics of the OFDM symbols include cyclic shift properties of the OFDM symbols, such as the characteristic that a first portion of an OFDM symbol is the same as a last portion of the OFDM symbol. One or more of the plurality of different synchronization signals in the data signal can be located using the detected symbol boundaries of the OFDM symbols to determine a frame boundary of a data frame in the data signal.

Abstract: A plurality of received signals are received at a first communication device, the plurality of received signals corresponding to at least one training signal having been transmitted by a second communication device a plurality of times via a plurality of antennas by the second communication device applying a respective antenna weight vector from a plurality of different antenna weight vectors each time the at least one training signal is transmitted. The first communication device generates a transmitter antenna weight vector based on a mathematical combination of at least i) the plurality of received signals, ii) the antenna weight vectors applied by the second communication device when transmitting the at least one training signal the plurality of times, and iii) the at least one training signal. The first communication device transmits the transmitter antenna weight vector to the second communication device.

Abstract: A method and apparatus for antenna switching, grouping, and channel assignments in wireless communication systems. The invention allows multiuser diversity to be exploited with simple antenna operations, therefore increasing the capacity and performance of wireless communications systems. Channel characteristics indicative of signal reception quality for downlink or bi-directional traffic for each channel/antenna resource combination are measured or estimated at a subscriber. Corresponding channel characteristic information is returned to the base station. Channel characteristics information may also be measured or estimated for uplink or bi-directional signals received at each of multiple receive antenna resources. The base station employs channel allocation logic to assign uplink, downlink and/or bi-directional channels for multiple subscribers based on channel characteristics measured and/or estimated for the uplink, downlink and/or bi-directional channels.

Abstract: A first plurality of training data units are transmitted via a plurality of antennas of a first station as part of a first transmit beamforming training procedure. Subsequently, a second plurality of training data units are received via the plurality of antennas as part of second transmit beamforming procedure while the first station applies a single receive antenna configuration. The second plurality of training data units includes an information element that specifies a feedback from a second station, the feedback including an identifier corresponding to one of the training data units in the first plurality of data units. The first station transmits a feedback message to the second station, that includes (i) one or more indicators of one or more training data units selected from the second plurality of training data units, and (ii) a request to perform a subsequent beamforming training procedure.

Abstract: A receiver of a wireless communication device, the receiver including a fast Fourier transform module, a first power measuring module, and a gain control module. The fast Fourier transform module is configured to convert a signal from a time domain to a frequency domain. The signal includes a plurality of reference signals. The reference signals have a predetermined power. The first power measuring module is configured to generate a first power measurement of the signal in the frequency domain based on the plurality of reference signals. The gain control module is configured to adjust a gain of the receiver based on the first power measurement.