Abstract: The present disclosure includes systems and techniques relating to wireless local area network devices. Systems and techniques include accessing a data stream intended for transmission to a single wireless communication device, multiplexing the data stream onto two or more radio pathways to produce a data packet, operating the two or more radio pathways to respectively use two or more groups of orthogonal frequency division multiplexing (OFDM) subcarriers to generate two or more different portions of the data packet, the two or more groups of OFDM subcarriers being respectively assigned to two or more frequency bands, and transmitting the data packet to the single wireless communication device by concurrent transmissions of the two or more different portions via the two or more frequency bands.

Abstract: An access point including a first transmitter and a second transmitter. The first transmitter is configured to (i) during a first window, transmit a first data stream to a first client station, and (ii) during a second window, transmit a second data stream to a second client station. The second transmitter is configured to: during the first window and while the first transmitter transmits the first data stream to the first client station, transmit a third data stream to a third client station; during a first portion of the second window and while the first transmitter is transmitting the second data stream to the second client station, refrain from transmitting a fourth data stream to a fourth client station; and subsequent to the first transmitter completing the transmission of the second data stream and during a second portion of the second window, transmit the fourth data stream to the fourth client station.

Abstract: A modulation coding scheme (MCS) is selected from i) a first set of MCSs when the selected channel bandwidth is a first channel bandwidth, or ii) a second set of MCSs when the selected channel bandwidth is a second channel bandwidth, wherein the first set of MCSs is different than the second set of MCSs, and the second set of MCSs excludes MCSs from the first set of MCSs that will result in a padding-related constraint not being met when the second channel bandwidth is to be used. Information bits are interleaved, which includes applying a frequency rotation. The information bits are modulated according to the selected MCS. A plurality of Orthogonal Frequency Division Multiplexing (OFDM) symbols are generated using the modulated information bits.

Abstract: A plurality of diagonal matrices Ci is determined, where the plurality of diagonal matrices Ci is for modifying a plurality of transmit signals to be transmitted via a plurality of transmit antennas, each diagonal matrix Ci for modifying an i-th block of sub-carriers, adjacent in frequency, in the plurality of transmit signals. The plurality of diagonal matrices Ci is used to modify the plurality of transmit signals to implement transmit diversity.

Abstract: A method in a communication network includes obtaining descriptions of a plurality of communication channels each communication channel associated with a different one of a plurality of receivers; and generating a plurality of steering vectors, one for each of the plurality of receivers, using the descriptions of the plurality of communication channels; wherein each steering vector is used to transmit data to a corresponding one of the plurality receivers via a plurality of antennas and over a corresponding one of the communication channels simultaneously and wherein each steering vector is used to communicate data on a different one of the plurality of communication channels, and wherein each steering vector is generated to reduce interference on a corresponding communication channel caused by simultaneous transmission of data on other communication channels.

Abstract: In a method for generating a physical layer (PHY) data unit for transmission via a communication channel, the PHY data unit is generated according to a first PHY format when the PHY data unit is to be transmitted in a regular mode, wherein the first PHY format corresponds to a first bandwidth. The PHY data unit is generated according to a second PHY format when the PHY data unit is to be transmitted in an extended range mode, wherein the second PHY format corresponds to a second bandwidth. A preamble of the PHY data unit is modulated such that a receiving device can auto-detect whether the PHY data unit was transmitted at the first bandwidth or the second bandwidth.

Abstract: A first communication device transmits a data unit configured to prompt a second communication device to transmit a non-sounding data unit with a number of spatial streams equal to a number of transmit antennas available at the second communication device, wherein the second communication device does not support implicit transmit beamforming. Responsive to the data unit transmitted from the first communication device, the non-sounding data unit is received from the second communication device. The first communication device develops an estimate of a reverse channel via which the non-sounding data unit traveled based on the non-sounding data unit. The first communication device develops a transmit beamforming matrix based on the estimate of the reverse channel, the transmit beamforming matrix for the first communication device to utilize when transmitting via a forward channel.

Abstract: A method of antenna selection, in a MIMO system in which a transmitter having a first plurality of RF chains communicates with a receiver having a second plurality of RF chains, includes transmitting consecutive sounding packets produced by the first plurality of RF chains. The consecutive sounding packets each include a training symbol, and collectively sound a full-size channel for the MIMO system. The method also includes receiving channel state information for each of a plurality of scaled sub-channel estimates determined at the receiver. The channel state information includes at least one of respective gain factors that were applied to the consecutive sounding packets received at the receiver and respective scaling factors that were applied to sub-channel estimates determined at the receiver. The method also includes adjusting power levels applied to the first plurality of RF chains in response to receiving the channel state information.

Abstract: In a method for generating a physical layer (PHY) data unit for transmission via a communication channel, information bits to be included in the PHY data unit are encoded using a forward error correction (FEC) encoder. Also, the information bits are encoded according to a block coding scheme, where m copies of each bit are included in the information bits, and one or more bits in the m copies of each bit are flipped. The information bits are mapped to a plurality of constellation symbols, and a plurality of orthogonal frequency division multiplexing (OFDM) symbols are generated to include the plurality of constellation symbols. The PHY data unit is generated to include the plurality of OFDM symbols.

Abstract: A method for estimating and compensating for noise on antennas of a multi-antenna wireless system. The method includes receiving multiple signals via multiple receive antennas of a receiver, where each of the signals is received via a respective antenna. The method further includes estimating noise power imbalance corresponding to the receive antennas based on the multiple signals.

Abstract: Systems and methods are provided for decoding a signal vector in a transmit diversity scheme for varying channels. Information obtained in more than one symbol period are treated as a single received vector, and each of the received signal vectors may be processed to reduce the effects of varying channel characteristics. The received signal vectors may be combined by addition and decoded using a maximum-likelihood decoder. In some embodiments, the received signal vectors are processed separately and then combined. In other embodiments, the received signal vectors are combined and then processed. In some embodiments, zero-forced linear equalization techniques are used to processed the received signals. In some embodiments the signal vectors and varying channel response matrices are broken down to equivalent forms in order to simplify the processing.

Abstract: In a method of calibrating a wireless communication device, a first sounding packet is transmitted from the wireless communication device to a calibration station. A first channel descriptor is generated based on the first sounding packet. A second sounding packet is transmitted from the calibration station to the wireless communication device. A second channel descriptor is generated based on the second sounding packet. The first channel descriptor and the second channel descriptor are obtained at a controller. Calibration coefficients indicative of one or both of phase imbalance and amplitude imbalance between a receive radio frequency (RF) chain and a transmit RF chain at the wireless communication device are generated based on the first and the second channel descriptors. The calibration coefficients are sent from the controller to the wireless communication device.

Abstract: A transceiver utilizes a spatial spreading matrix to distribute two or more encoded spatial data streams to multiple antennas. The spatial spreading matrix satisfies one or more of the following two constraints: (a) the ratio of squared norms of the sum of the components of a row, for different rows of the spatial spreading matrix, is equal to a first constant sequence, and (b) the ratio of squared norms of the sum of a symbol S1 to be transmitted, when the symbol S1 is equal to 1 or ?1, multiplied by each of the components of a row, for different rows of the spatial spreading matrix, is equal to a second constant sequence.

Abstract: In a method for generating a physical layer (PHY) data unit for transmission via a communication channel, information bits to be included in the PHY data unit are encoded using a forward error correction (FEC) encoder. The information bits are mapped to a constellation symbols. Additionally, either the information bits are encoded according to a block coding scheme, or the constellation symbols are encoded according to the block coding scheme. Orthogonal frequency division multiplexing (OFDM) symbols are generated to include the constellation symbols and the PHY data unit is generated to include the OFDM symbols.

Abstract: In a method for generating a data unit conforming to a first communication protocol, a first field and a second field to be included in a preamble of the data unit are generated. The first field includes a first set of one or more information bits that indicate a duration of the data unit and is formatted such that the first field allows a receiver device that conforms to a second communication protocol to determine the duration of the data unit. The second field includes a second set of one or more information bits that indicate to a receiver device that conforms to the first communication protocol that the data unit conforms to the first communication protocol. The first field and the second field are modulated using a modulation scheme specified for a field corresponding to the first field and the second field, respectively, by the second communication protocol.

Abstract: An access point including a first transmitter and a second transmitter. The first transmitter is configured to (i) during a first window, transmit a first data stream to a first client station, and (ii) during a second window, transmit a second data stream to a second client station. The second transmitter is configured to: during the first window and while the first transmitter transmits the first data stream to the first client station, transmit a third data stream to a third client station; during a first portion of the second window and while the first transmitter is transmitting the second data stream to the second client station, refrain from transmitting a fourth data stream to a fourth client station; and subsequent to the first transmitter completing the transmission of the second data stream and during a second portion of the second window, transmit the fourth data stream to the fourth client station.

Abstract: In a method for generating a PHY data unit for transmission via a communication channel, a modulation scheme is selected from a plurality of modulation schemes, information bits are encoded to generate encoded data using one or more encoders, and an interleaving parameter NCOL is selected using the selected modulation scheme. NCOL varies for different modulation schemes. The encoded data is interleaved, which includes entering the encoded data into NROW rows and reading the encoded data out in NCOL columns. The payload information of the PHY data unit is modulated according to the modulation scheme, and a plurality of OFDM symbols is formed based on the modulated payload information.

Abstract: An equalizer is applied to a signal to be transmitted via at least one multiple input, multiple output (MIMO) channel or received via at least one MIMO channel using a matrix equalizer computational device. Channel state information (CSI) is received, and the CSI is provided as an input to the matrix equalizer computational device when the matrix equalizer computational device is not needed for matrix equalization. One or more transmit beamsteering codewords are selected from a transmit beamsteering codebook based on output generated by the matrix equalizer computational device in response to the CSI input to the matrix equalizer computational device.

Abstract: In one or more aspects data packets are iteratively transmitted to a receiver using predefined spatial mapping matrices, channel estimates are received from the receiver responsive to iteratively transmitted data packets, and one of the predefined spatial mapping matrices is selected for transmitting additional data packets to the receiver based on the received channel estimates.

Abstract: An AP including a MAC module to designate a predetermined time period to communicate with a plurality of client stations associated with the AP via a channel. The MAC module instructs remaining client stations associated with the AP to not transmit data during the predetermined time period. The MAC module receives, during the predetermined time period, data transmitted by the plurality of client stations without sensing the channel, and receives, at a time other than the predetermined time period, data transmitted by the remaining client stations by sensing the channel. An acknowledgment generating module generates acknowledgements in response to receiving data from the plurality of client stations. The MAC module aggregates the acknowledgements in a single aggregated frame, which includes a plurality of sub-frames, each sub-frame including one of the acknowledgements. The MAC module transmits the single aggregated frame to the plurality of client stations during the predetermined time period.