| Patent application number | Description | Published |
|---|
| 20080279317 | BICM DECODING IN THE PRESENCE OF CO-CHANNEL INTERFERENCE - Systems and methods are provided for computing soft information for digital information based on a received signal, where the received signal suffers from noise and interference. A receiver that decodes the received signal may estimate channel information, such as the channel gain, associated with the interfering source. The receiver may also obtain modulation information through a backbone network or by decoding control information transmitted by the interfering source. Using the modulation information and the channel information, the receiver may estimate the effect that interference has on the received signal, and may compute soft information (e.g., a log-likelihood ratio) for the digital information. | 11-13-2008 |
| 20090022093 | WIRELESS NETWORK WITH SIMULTANEOUS UPLINK TRANSMISSION OF INDEPENDENT DATA FROM MULTIPLE CLIENT STATIONS - A wireless network comprises R client stations that respectively generate simultaneous uplink transmission (SUT) data, where R is an integer greater than one. An access point (AP) receives SUT data from each of the R client stations during an SUT period. | 01-22-2009 |
| 20090022128 | ACCESS POINT WITH SIMULTANEOUS DOWNLINK TRANSMISSION OF INDEPENDENT DATA FOR MULTIPLE CLIENT STATIONS - A wireless network device comprises R modulation modules that receive R independent data streams, that modulate the R independent data streams, and that apply a multiplexing matrix to generate M modulated and multiplexed data streams, respectively, where R and M are integers greater than one. M summing modules sum portions of each of the M modulated and multiplexed data streams to generate M transmit data streams. M transmitters simultaneously transmit the M transmit data streams during a simultaneous downlink transmission (SDT) period. | 01-22-2009 |
| 20090047969 | PILOT DESIGN FOR UNIVERSAL FREQUENCY REUSE IN CELLULAR ORTHOGONAL FREQUENCY-DIVISION MULTIPLEXING SYSTEMS - Systems and methods are provided for transmitting information between an intended source and a receiver to minimize co-channel interference from at least one interfering source. Pilot subcarriers and data subcarriers may be broadcast from an intended source arid at least one interfering source. The pilot subcarriers may be shared across base stations or distributed among base stations in frequency, in time, or both. In addition, the frequency reuse factor of the pilot subcarriers may be different than the frequency reuse factor of the data subcarriers. A receiver receives a composite signal that corresponds with an intended signal from an intended source and an interfering signal from at least one interfering source. The portion of the received signal that corresponds to the intended signal may be recovered by the receiver based on the broadcast of the pilot subcarriers. | 02-19-2009 |
| 20090051592 | Pseudo-Omni-Directional Beamforming with Multiple Narrow-Band Beams - In a technique for communication with a station on a wireless network, the technique includes forming a plurality of narrow-band beams, each having a different angular direction from an antenna of a base station and collectively distributed over a beamspace to form a pseudo-omni-directional beam pattern. That beamspace may span an entire spherical region or a portion thereof, for example, when the narrow-band beams are broadcast over a sector of an entire spherical region. The technique may assign each of the plurality of narrow-band beams to a different frequency band (such as a different channel band or sub-channel) on the wireless network. The technique may simultaneously broadcast the plurality of narrow-band beams in a time-varying manner such that the angular direction of each of the plurality of narrow-band beams varies with time, where that variation may be random or ordered. | 02-26-2009 |
| 20090252104 | Physical Layer Frame Format Design for Wideband Wireless Communications Systems - 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. | 10-08-2009 |
| 20090262855 | DATA SYMBOL MAPPING FOR MULTIPLE-INPUT MULTIPLE-OUTPUT HYBRID AUTOMATIC REPEAT REQUEST - A system includes an encoding module, a symbol selection module, a subcarrier selection module, and a mapping module. The encoding module receives symbols for transmission over K subcarriers and T antennas, encodes the symbols using a space time code, and generates space time coded (STC) versions of the symbols, where K and T are integers greater than 1. The symbol selection module selects T adjacent ones of the symbols and selects STC versions of the T adjacent ones of the symbols. The subcarrier selection module selects one of the K subcarriers for transmitting the T adjacent ones of the symbols and the STC versions of the T adjacent ones of the symbols. The mapping module maps the T adjacent ones of the symbols onto the T antennas for transmission over the selected one of the K subcarriers, respectively, and maps the STC versions of the T adjacent ones of the symbols onto the T antennas for transmission over the selected one of the K subcarriers. | 10-22-2009 |
| 20090279633 | SYMBOL VECTOR-LEVEL COMBINING TRANSMITTER FOR INCREMENTAL REDUNDANCY HARQ WITH MIMO - Techniques are provided for transmitting and receiving a mother code in an incremental redundancy hybrid automatic repeat-request protocol. A set of information bits corresponding to a message may be encoded and interleaved to produce the mother code. Each bit position of the mother code may be mapped to an output symbol, and each output symbol may be mapped to an antenna for transmission. One or more transmissions of symbols contained in the output symbols may be performed, where each transmission may include puncturing the mother code by selecting one or more symbols from the of output symbols, and transmitting each symbol in the one or more symbols on an antenna corresponding to that symbol. The mother code may be decoded, in part, by determining combinable bits contained within a set of received symbols, and computing one or more log-likelihood ratio values corresponding to each symbol in the set of received symbols. | 11-12-2009 |
| 20090282311 | SYMBOL VECTOR-LEVEL COMBINING RECEIVER FOR INCREMENTAL REDUNDANCY HARQ WITH MIMO - Techniques are provided for transmitting and receiving a mother code in an incremental redundancy hybrid automatic repeat-request protocol. A set of information bits corresponding to a message may be encoded and interleaved to produce the mother code. Each bit position of the mother code may be mapped to an output symbol, and each output symbol may be mapped to an antenna for transmission. One or more transmissions of symbols contained in the output symbols may be performed, where each transmission may include puncturing the mother code by selecting one or more symbols from the of output symbols, and transmitting each symbol in the one or more symbols on an antenna corresponding to that symbol. The mother code may be decoded, in part, by determining combinable bits contained within a set of received symbols, and computing one or more log-likelihood ratio values corresponding to each symbol in the set of received symbols. | 11-12-2009 |
| 20090285240 | Efficient Physical Layer Preamble Format - A method of generating a data unit preamble includes generating a first field associated with at least one of packet synchronization information or frame boundary indication, and generating a second field associated with channel estimation, including generating a first channel estimation sequence (CES) symbol and generating a second CES symbol, so that at least one of 1) a sequence in the first field serves as a cyclic prefix of the first CES symbol, 2) a beginning portion of the second CES symbol serves as a cyclic postfix of the first CES symbol, or 3) an ending portion of the first CES symbol serves as a cyclic prefix of the second CES symbol. | 11-19-2009 |
| 20090285241 | Efficient Physical Layer Preamble Format - A method for generating a preamble of a data unit includes generating a short training field (STF) of the preamble to include one of a repeating series of a sequences or a repeating series of b sequences, such that a and b are complementary sequences, a sum of out-of-phase aperiodic autocorrelation coefficients of a and b is zero, and where the STF is associated with at least synchronization information, and generating a long training field (LTF) of the preamble after the STF to include a′ sequences and b′ sequences, such that a′ is the sequence a cyclically shifted by zero or more positions, b′ is the sequence b cyclically shifted by zero or more positions, and where the LTF is associated with channel estimation information. | 11-19-2009 |
| 20090285319 | Efficient Physical Layer Preamble Format - 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. | 11-19-2009 |
| 20090285339 | Apparatus for Generating Spreading Sequences and Determining Correlation - 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. | 11-19-2009 |
| 20100008436 | Physical Layer Frame Format Design for Wideband Wireless Communications Systems - 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. | 01-14-2010 |
| 20100080266 | Physical Layer Data Unit Format - In a wireless communication system wherein 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 and a first cover code, a method is for generating a physical layer (PHY) data unit that conforms to a second format, wherein the PHY data unit is for transmitting PHY information. A first portion of the PHY data unit is generated to indicate the PHY data unit conforms to the second format, wherein the first portion of the PHY data unit includes an STF spread with at least one of a second spread code different than the first spread code or a second cover code different than the first cover code. A second portion of the PHY data unit is generated according to the second format, wherein the second portion of the PHY data unit includes PHY information elements not specified by the first format. | 04-01-2010 |
| 20100157955 | Efficient Formats of Beacon, Announcement, and Beamforming Training Frames - A method includes generating a first data unit to be transmitted during a first time period to one or several stations assumed to be beamformed, including determining a time interval that separates the first time period from a second time period, such that a second data unit is transmitted during the second time period to one or several stations assumed to be beamformed, and generating a parameter indicative of the time interval, such that the first data unit includes the parameter. | 06-24-2010 |
| 20100215027 | Techniques for Flexible and Efficient Beamforming - A method includes generating a first data unit to be transmitted during a first time period, including generating a field that specifies a first number of beamforming training data units that can be communicated during a first training session; processing a second data unit received during a second time period, including determining whether the first training session was accepted based on a first field of the second data unit, and determining a second number of beamforming training data units that can be communicated during a second training session based on a second field of the second data unit; and if the first training session was accepted, causing the specified first number of beamforming training data units to be communicated during the first training session. | 08-26-2010 |
| 20100232475 | Equal Power Output Spatial Spreading Matrix for Use in a Wireless MIMO Communication System - A spatial spreading unit is configured to utilize a spatial spreading matrix to distribute two or more encoded spatial data streams to transmission antennas. The spatial spreading matrix has components (i) associated with each row of a row dimension having a number of rows equal to the number of the transmission antennas to be used to transmit the encoded spatial data streams and (ii) associated with each column of a column dimension having a number of columns equal to the number of the encoded spatial data streams to be transmitted. Additionally, the spatial spreading matrix satisfies one or more of the following two constraints: (1) 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 (2) the ratio of squared norms of the sum of a symbol Sl to be transmitted, when the symbol Sl 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. | 09-16-2010 |
| 20100248635 | Sounding And Steering Protocols For Wireless Communications - The present disclosure includes systems, apparatuses, and techniques relating to wireless local area network devices. Systems, apparatuses, and techniques include communicating with multiple wireless communication devices to determine characteristics of spatial wireless channels, determining steering matrices based on one or more outputs of the communicating, and transmitting signals that concurrently provide data to the wireless communication devices via different spatial wireless channels. The signals can be spatially steered to the wireless communication devices based on the steering matrices. | 09-30-2010 |
| 20100260159 | PHYSICAL LAYER FRAME FORMAT FOR WLAN - In a method for generating a data unit for transmission via a communication channel, wherein the data unit conforms to a first communication protocol, a preamble of the data unit is generated. The preamble includes a first field having information that indicates a duration of the data unit, the first field being formatted such that the first field is decodable by a receiver device that conforms to a second communication protocol but does not conform to the first communication protocol to determine the duration of the data unit based on the first field. Additionally, the preamble is formatted such that a portion of the preamble is decodable by a receiver device that conforms to a third communication protocol but does not conform to the first communication protocol. Also, the preamble is formatted such that a receiver device that conforms to the first communication protocol can determine that the data unit conforms to the first communication protocol. A data portion of the data unit that conforms to the first communication protocol and does not conform to either (i) the second communication protocol or (ii) the third communication protocol is generated. | 10-14-2010 |
| 20100322336 | Beamforming to a Subset of Receive Antennas in a Wireless MIMO Communication System - In a method for controlling transmission of an information signal to a multiplicity of receive antennas associated with one or more receivers a steering matrix is developed using a subset of receive antennas, wherein the subset of receive antennas includes less than all of the multiplicity of receive antennas. Transmission of the information signal via a plurality of transmit antennas is controlled using the steering matrix. | 12-23-2010 |
| 20110069688 | Short Packet for Use in Beamforming - A method for generating a beamforming training (BFT) unit includes generating a physical layer (PHY) preamble of the BFT unit and generating a first encoding block and a second encoding block using PHY data and MAC data, including at least one of i) using a number of padding bits in a PHY layer of the BFT unit such that the BFT unit consists of the PHY preamble, the first encoding block, and the second encoding block, and ii) generating a MAC protocol data unit (MPDU) having a length such that the BFT unit consists of the PHY preamble, the first encoding block, and the second encoding block. | 03-24-2011 |
