Abstract: A plurality of beacon data units are generated, and each beacon data unit in the plurality of beacon data units includes an indication that the beacon data unit can be used for transmit beamforming training. The plurality of beacon data units are transmitted via a plurality of antennas during a timeslot reserved for the transmission of beacons. A different beamforming vector is applied to a beamforming network as each beacon data unit is transmitted. In another aspect, a first beamforming training transmission corrupted by a collision is received. A first station to which the first beamforming training transmission corresponds is determined based on the first beamforming training transmission corrupted by the collision. In response to determining the first station, a signal is transmitted to the first station to prompt the first station to transmit a second beamforming training transmission.

Abstract: Systems and methods are provided for processing a payload portion of a received signal in a single carrier mode or a multiple carrier mode based on a portion of the received signal. A single carrier signaling portion is received at a first rate, and whether the payload portion of the signal is a single carrier signal or a multiple carrier signal is detected from the received single carrier signaling portion. The payload portion of the received signal is received at the first rate and demodulated in a single carrier mode if the detecting determines that the payload portion of the received signal is a single carrier signal, and the payload portion of the received signal is demodulated in a multiple carrier mode if the detecting determines that the payload portion of the received signal is a multiple carrier signal.

Abstract: In a wireless communication system in which communication devices exchange information utilizing data units that conform to a first format, wherein the first format includes a short training field (STF) spread with a first spread code, a method for generating a physical layer (PHY) data unit that conforms to a second format includes generating a first portion of the PHY data unit to indicate the PHY data unit conforms to the second format. The first portion of the PHY data unit includes an STF spread with a second spread code different than the first spread code. The method also includes generating a second portion of the PHY data unit according to the second format. The second portion of the PHY data unit includes PHY information elements not specified by the first format.

Abstract: Systems and methods for using non-crystal-based reference oscillators in the transmission and reception of frequency-modulated signals are disclosed. To protect against intrusion on neighboring designated frequency bands, guard bands, having a collective width greater than the total expected error based on the contribution of the frequency error from the non-crystal-based oscillators in the transmitter and/or receiver, can be designated. To protect against inter-channel interference within a designated frequency band, transmitters and receivers can include static sub-bandwidths wider than any possible total frequency error, such that it would be impossible for a transmitter or receiver to attempt to communicate on an unintended sub-band.

Abstract: Systems, methods, and other embodiments associated with preamble detection based on repeated preamble codes are described. According to one embodiment, an apparatus is provided that wirelessly receives a signal and calculates a differential output corresponding to a multiplication of the signal and a delayed version of the signal. A cross correlation is performed between the differential output and a known preamble pattern to produce a cross correlation output. A moving average calculation is performed on the cross correlation output to produce an average cross correlation. One or more peaks are detected in the average cross correlation when the average cross correlation has an amplitude greater than a threshold. When the one or more detected peaks meets predetermined criteria, the apparatus provides information about at least one of the detected peaks for subsequent signal processing.

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: A circuit for use in a complementary Golay sequence generator or in a complementary Golay sequence correlator includes an input configured to receive an input signal, a set of delay elements, including delay elements corresponding to respective delays of 1, 2, 4, 8, 16, 32, and 64, and a set of multipliers interconnected with the input and the set of delay elements. The set of multipliers is configured to apply weight factors, and the weight factors define the sequence 1,1,?1,1,?1,1,?1. The circuit also includes a pair of outputs configured to output, in response to the input signal, one of (i) a pair of complementary Golay sequences or (ii) a pair of correlation output signals, using (a) the set of delay elements and (b) the set of weight multipliers.

Abstract: Systems and methods are provided for processing a payload portion of a received signal in a single carrier mode or a multiple carrier mode based on a portion of the received signal. A single carrier signaling portion is received at a first rate, and whether the payload portion of the signal is a single carrier signal or a multiple carrier signal is detected from the received single carrier signaling portion. The payload portion of the received signal is received at the first rate and demodulated in a single carrier mode if the detecting determines that the payload portion of the received signal is a single carrier signal, and the payload portion of the received signal is demodulated in a multiple carrier mode if the detecting determines that the payload portion of the received signal is a multiple carrier signal.

Abstract: Systems and techniques relating to wireless communications are described.

Abstract: In a method for synchronizing a receiver to a synchronous signal, in a signal having been processed based on an automatic gain control (AGC) with a varying gain, a symbol is detected. An estimated beginning of a subsequent frame is determined based on the detected symbol. A gain of the AGC is fixed for a period during which the estimated start of the subsequent frame is processed by the AGC. A transform of the signal is analyzed to determine if the estimated start of the subsequent frame corresponds to an actual start of the subsequent frame. If the estimated start of the subsequent frame does not corresponds to the actual start of the subsequent frame, the gain of the AGC is allowed to resume varying and, a further symbol in the signal is detected, the signal having been processed based on the varying gain of the AGC.

Abstract: In a wireless communication system wherein communication devices exchange information utilizing data units that conform to a first format, a beamforming training (BFT) data unit that conforms to a second format is transmitted, wherein a length of the BFT data unit is shorter than lengths supported by the first format, wherein the BFT data unit is for transmitting PHY beamforming training information. Information to indicate the BFT data unit conforms to the second format is transmitted to a receiving device. The BFT data unit is generated according to the second format, wherein the BFT data unit includes BFT information elements. The BFT data unit is then transmitted to the receiving device.

Abstract: In a method for beamforming in communication a system, a plurality of different antenna weight vectors are generated. Each of the plurality of antenna weight vectors is a respective base vector of a unitary matrix. At least one training signal is transmitted a plurality of times via a plurality of antennas. A respective antenna weight vector from the plurality of different antenna weight vectors is applied each time the at least one training signal is transmitted. Feedback signals are received, where the feedback signals correspond to the at least one training signal transmitted the plurality of times and received at a receiver. A transmitter antenna weight vector is generated based on a mathematical combination of at least (i) the at least one training signal and (ii) the feedback signals.

Abstract: Systems and methods are provided for processing a payload portion of a received signal in a single carrier mode or a multiple carrier mode based on a portion of the received signal. A single carrier signaling portion is received at a first rate, and whether the payload portion of the signal is a single carrier signal or a multiple carrier signal is detected from the received single carrier signaling portion. The payload portion of the received signal is received at the first rate and demodulated in a single carrier mode if the detecting determines that the payload portion of the received signal is a single carrier signal, and the payload portion of the received signal is demodulated in a multiple carrier mode if the detecting determines that the payload portion of the received signal is a multiple carrier signal.

Abstract: This disclosure describes systems and techniques for implementing a touchscreen. These systems and/or techniques enable processing of a signal generated from one or more sensors of a touchscreen to reduce noise and increase accuracy.

Abstract: An apparatus includes a signal generator to output one of a first sequence or a second sequence and to augment sequences with cover codes, such that a sum of out-of-phase aperiodic autocorrelation coefficients of the first sequence and the second sequence of is zero, a physical layer preamble controller to control the signal generator to generate a preamble of a data unit, including a short training field (STF) formatter to cause the signal generator to generate an STF for use in at least frame synchronization, and a long training field (LTF) formatter to cause the signal generator to generate an LTF for use in at least channel estimation, such that the STF formatter controls the signal generator to include the first sequence in a last portion of the STF, and the LTF formatter controls the signal generator to include the second sequence in a beginning portion of the LTF.

Abstract: A system and method of extracting data from data packets transmitted over a wireless network includes receiving a data packet having a preamble portion and a payload portion. The preamble portion is cross correlated with a first known spreading sequence to generate a first timing signal and the preamble portion is cross correlated with a second known spreading signal to generate a frame timing signal. An impulse is detected in the first timing signal and a first timing parameter is set based upon the detected impulse in the first timing signal. An impulse is detected in the frame timing signal and a frame timing parameter is set based upon the detected impulse in the frame timing signal. Data is extracted from the received payload portion according to the first timing parameter and the frame timing parameter.

Abstract: Systems and methods are provided for processing a payload portion of a received signal in a single carrier mode or a multiple carrier mode using a wireless channel receiver based on a portion of the received signal, where a signaling portion of the received signal is a single carrier signal. A single carrier signaling portion is received, and whether the payload portion of the signal is a single carrier signal or a multiple carrier signal is detected from the received single carrier signaling portion. The payload portion of the received signal is demodulated in a single carrier mode if the detecting determines that the payload portion of the received signal is a single carrier signal, and the payload portion of the received signal is demodulated in a multiple carrier mode if the detecting determines that the payload portion of the received signal is a multiple carrier signal. Data from the demodulated payload portion of the received signal is stored in a computer-readable memory.

Abstract: A system including a sampling module that generates samples of RF signals on a first channel during first, second, and third periods, which do not overlap. A difference module determines a first difference between i) a first count of polarity reversals during the first period and ii) a second count of polarity reversals during the second period; a second difference between i) the second count and ii) a third count of polarity reversals during the third period; and a third difference between the first and second differences. A third module determines a frequency of the RF signals based on at least one of the first and second counts, determines a frequency variation of the RF signals based on the first and second counts, and identifies a radar type of the RF signals based on at least one of the third difference and the frequency variation.

Abstract: Refining beamforming techniques for use in a communication system. In one embodiment, a method for beamforming in a communication system includes generating multiple training signals to be transmitted via multiple antennas over a communication channel, including applying a different antenna weight vector (AWV) to each of the multiple training signals. The method further includes receiving feedback generated using the multiple training signals, where the feedback includes a transmitter AWV for use with the multiple antennas and/or channel state information (CSI) descriptive of the communication channel.

Abstract: A method for generating a preamble of a data unit for transmission via a communication channel includes generating a first field of the preamble using one of a first sequence or a second sequence, such that the first sequence and the second sequence are complementary sequences such that a sum of out-of-phase aperiodic autocorrelation coefficients of the first sequence and the second sequence is zero; generating, using the other one of the first sequence or the second sequence, an indicator of a start of a second field of the preamble, the second field associated with channel estimation information, such that the indicator of the start of the second field immediately follows the first field; and generating the second field of the preamble.