Patent application number | Description | Published |
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 |
20110026623 | Methods and Apparatus for WLAN Transmission - In a method for generating a physical layer (PHY) data unit for transmission via a communication channel, a first set of modulation coding schemes (MCSs) and a second set of MCSs that correspond to a number of spatial streams and a number of encoders are provided. The first set of MCSs correspond to a first channel bandwidth and the second set of MCSs correspond to a second channel bandwidth, and the first set of MCSs is different than the second set of MCSs. An MCS is selected from the first set of MCSs when the PHY data unit is to be transmitted using a channel having the first channel bandwidth, and the MCS is selected from the second set of MCSs when the PHY data unit is to be transmitted using a channel having the second channel bandwidth. Information bits are encoded using the number of encoders and according to the selected MCS, and the encoded information bits are parsed into the number of spatial streams. The encoded information bits are modulated according to the MCS, and a plurality of OFDM symbols are formed based on the modulated encoded information bits. | 02-03-2011 |
20110116401 | Multi-Channel Wireless Communications - Systems and techniques relating to wireless communications are described. A described technique includes monitoring wireless communication channels, including a first channel and a second channel, to produce a monitoring output, determining a first transmission period for the first channel, determining a second transmission period for the second channel, transmitting, based on the first transmission period, a first packet on the first channel to cause one or more wireless communication devices to set a transmission protection period for the first channel and the second channel based on a reception of the first packet, transmitting, based on the second transmission period, a second packet on the second channel, and monitoring, after the end of the first transmission period, for one or more acknowledgements. An end of the second transmission period can be aligned with an end of the first transmission period. | 05-19-2011 |
20110128929 | Method and Apparatus for Sounding Multiple Stations - One or more stations to provide sounding feedback in response to a training signal sequence are determined, and a schedule for the one or more stations to provide sounding feedback is determined based on capabilities of the one or more stations to transmit sounding feedback at a defined time period after an end of the training signal sequence. A communication frame is generated that includes i) an indication of a request for the plurality of stations to provide sounding feedback corresponding to the training signal sequence, and ii) an indication of when the one or more stations are to transmit sounding feedback. The communication frame is transmitted along with the training sequence. | 06-02-2011 |
20110128947 | Method and Apparatus for Sounding Multiple Stations - A plurality of stations to provide sounding feedback in response to a training signal sequence is determined, and a communication frame is generated that includes i) an indication of a request for the plurality of stations to provide sounding feedback corresponding to the training signal sequence, and ii) information indicative of when each of the plurality of stations should transmit sounding feedback, and iii) sounding feedback parameters. The communication frame is transmitted along with the training sequence. | 06-02-2011 |
20110310827 | ALTERNATE FEEDBACK TYPES FOR DOWNLINK MULTIPLE USER MIMO CONFIGURATIONS - 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. | 12-22-2011 |
20120002756 | Modulation of Signal Field in a WLAN Frame Header - A plurality of training fields of a preamble of a physical layer data unit are generated, and training fields of the plurality of training fields are mapped to respective signal streams of a plurality of streams using a mapping matrix. A signal field of the preamble of the data unit is generated, and the signal field is mapped to the plurality of signal streams using a column of the mapping matrix. The plurality of signal streams are mapped to a plurality of spatial streams, and at least i) the plurality of training fields and ii) the signal field are transmitted via the plurality of spatial streams. | 01-05-2012 |
20120008643 | Cyclic Shift Delays In Multi-User Packets With Resolvable Very High Throughput Long Training Fields (VHTLTFs) - A system including a training field generator module, a stream generator module, and a cyclic shift delay module. The training field generator module generates training fields to be transmitted in a packet to client stations. The stream generator module generates streams to be transmitted in the packet. First streams (i) are designated for a first client station and (ii) include the training fields. Second streams (i) are designated for a second client station and (ii) include the training fields. The cyclic shift delay module applies cyclic shift delay values to the streams. First cyclic shift delay values are respectively applied to the first streams. Second cyclic shift delay values are respectively applied to the second streams. At least one of the second cyclic shift delay values is equal to one of the first cyclic shift delay values. Alternatively, the second values are different than the first values. | 01-12-2012 |
20120039406 | CHANNEL DESCRIPTION FEEDBACK IN A COMMUNICATION SYSTEM - In a method for estimating a channel between a transmitter and a receiver in a communication network, a plurality of training signal fields are received at the receiver. Each training signal field includes a plurality of orthogonal frequency division multiplexing (OFDM) tones, and the OFDM tones include at least a plurality of training data tones and one or more pilot tones. Channel estimate data corresponding to the plurality of training data tones and the one or more pilot tones is determined. Channel estimate data corresponding to only a subset of the OFDM tones or data generated using the channel estimate data corresponding to the subset of OFDM tones is transmitted to the transmitter, wherein the subset excludes pilot tones. | 02-16-2012 |
20120076219 | STREAM PARSING IN A COMMUNICATION SYSTEM - In a method for parsing data in a data unit into a number of spatial streams, a modulation and coding scheme (MCS) is selected from a plurality of MCSs. Information bits are encoded using one or more encoders to generate coded bits, wherein the number of encoders used depends on the selected MCS. The coded bits into a number of spatial streams according to a first set of parsing rules if the coded bits satisfy a parsing constraint. The coded bits are parsed into the number of spatial streams according to a second set of parsing rules if the coded bits do not satisfy the parsing constraint. | 03-29-2012 |
20120087426 | COMPRESSED FEEDBACK FORMAT FOR WLAN - In a method for transmitting channel feedback data from a receiver to a transmitter, channel data for a plurality of orthogonal frequency division multiplexing (OFDM) tones for one or more spatial streams corresponding to a communication channel is determined. A plurality of angle values associated with the one or more spatial streams and one or more OFDM tones is determined. For each of the one or more spatial streams, a per-tone signal to noise ratio (PT-SNR) associated with one or more OFDM tones is determined, and an average signal to noise ratio (avg-SNR) is determined by averaging the signal to noise ratio (SNR) values. A feedback report is generated to include at least i) the plurality of angle values, ii) the PT-SNRs, and iii) the avg-SNR. The feedback report is included in a data unit to be transmitted from the receiver to the transmitter. | 04-12-2012 |
20120087436 | TONE REORDERING IN A WIRELESS COMMUNICATION SYSTEM - In a method for generating an orthogonal frequency division multiplexing (OFDM) symbol to be included in a PHY data unit for transmission via a communication channel, wherein the OFDM symbol includes a plurality of OFDM tones, information bits to be included in the OFDM symbol are encoded to generate encoded information bits. The encoded information bits are parsed into a plurality of spatial streams. The spatial streams, or space-time streams generated from the spatial streams, are mapped to transmit chains using a plurality of spatial mapping matrices corresponding to the plurality of OFDM tones. Additionally, one of i) reordering OFDM tones before spatial mapping is applied, or ii) reordering OFDM tones after spatial stream mapping is applied and reordering spatial mapping matrices to match the reordered OFDM tones is performed. The OFDM symbol to be included in the PHY data unit is generated. | 04-12-2012 |
20120201315 | Control Mode PHY for WLAN - A first preamble for a first data unit includes a first long training field and a first signal field modulated according to a first technique. The first data unit is generated according to a first data unit format and includes the first preamble. A second preamble, generated for a second data unit, includes a second signal field and a second long training field. Information in the second signal field is repeated and/or the second long training field is generated so that a duration of the second long training field is longer than a duration of the first long training field. A portion of the second signal field is modulated according to a second technique or a portion of the second long training field is modulated according to the second technique to signal to a receiver that the second data unit is formatted according to a second data unit format. | 08-09-2012 |
20120201316 | Control Mode PHY for WLAN - 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. | 08-09-2012 |
20120320889 | LOW BANDWIDTH PHY FOR WLAN - A method includes generating first and second preambles for first and second data units corresponding to first and second PHY modes, respectively. Generating the first preamble includes generating a first STF, LTF, and SIG field. The first SIG field includes an OFDM symbol modulated according to a first modulation technique. The OFDM symbol begins a first time interval, and ends a second time interval, after the first LTF begins. Generating the second preamble includes generating a second STF and LTF. The second STF has a greater duration, and different repeating sequence, than the first STF. The second LTF includes a second OFDM symbol modulated according to a second modulation technique, and at least partially occupying a location beginning a third time interval, and ending a fourth time interval, after the second LTF begins. The third and fourth time intervals are equal to the first and second time intervals, respectively. | 12-20-2012 |
20120320890 | LOW BANDWIDTH PHY FOR WLAN - A method, in a communication system utilizing channels for transmitting first PHY mode data units, includes generating first and second data units conforming to first and second PHY modes, respectively, causing the first data unit to be transmitted via a channel, determining a frequency band for transmitting the second data unit, and causing the second data unit to be transmitted via the frequency band. Generating the first and second data units includes generating first and second series of OFDM symbols, respectively. At least a portion of the second OFDM symbols includes more upper-edge than lower-edge guard tones, or vice versa. The frequency band has a bandwidth equal to the channel bandwidth divided by n≧2, and either a lowest or highest sub-band of one or more channels is excluded from the frequency band when the second OFDM symbols include more upper-edge or more lower-edge guard tones, respectively. | 12-20-2012 |
20120324315 | LOW BANDWIDTH PHY FOR WLAN - A method includes generating first and second data units corresponding to first and second PHY modes, respectively. Generating the first data unit includes FEC encoding first information bits, mapping the FEC-encoded bits to first constellation symbols, and generating first OFDM symbols to include the first constellation symbols. The first OFDM symbols utilize a first tone spacing, and include a first number of non-zero tones collectively spanning a first bandwidth. Generating the second data unit includes FEC encoding second information bits, block encoding the FEC-encoded bits, mapping the block-encoded bits to second constellation symbols, and generating second OFDM symbols to include the second constellation symbols. The second OFDM symbols utilize the first tone spacing, and include a second number of non-zero tones collectively spanning a second bandwidth less than the first bandwidth. The second number of non-zero tones is less than the first number of non-zero tones. | 12-20-2012 |
20120328034 | UPLINK TRAINING FOR MIMO IMPLICIT BEAMFORMING - In a method for beamforming in a multiple input multiple output (MIMO) communication system, a data unit is received from a communication device via a MIMO communication channel, and it is determined whether the data unit satisfies one or more selection criteria. Further, when it is determined that the data unit satisfies the one or more selection criteria, the data unit is selected to be used in developing a steering matrix for transmitting data units to the communication device. | 12-27-2012 |
20130044742 | SIGNAL FIELD DESIGN FOR WLAN - A method of generating packets for transmission in a wireless communication system. The method comprises generating a data packet and generating a null data packet. Generating the data packet includes generating a data packet signal (SIG) field including a first data packet SIG subfield indicating a first physical layer (PHY) parameter to a receiving device. Generating the data packet also includes generating a data field. Furthermore, generating the null data packet includes generating a null data packet SIG field. The null data packet SIG field includes a first null data packet SIG subfield indicating a second PHY parameter to a receiving device. The data packet SIG field excludes any SIG subfield indicating the second PHY parameter to a receiving device, and (ii) the null data packet SIG field excludes any SIG subfield indicating the first PHY parameter to a receiving device. | 02-21-2013 |
20130044743 | SIGNAL FIELD DESIGN FOR WLAN - A method of generating packets for transmission in a wireless communication system, wherein each packet includes a SIG field that includes a first SIG subfield, includes generating a data packet and a null data packet. Generating the data packet includes generating information bits of the first SIG subfield of the data packet and generating the data portion of the data packet. The information bits of the first SIG subfield of the data packet indicate, to a receiving device, a length corresponding to a data portion of the data packet. Generating the null data packet includes generating information bits of the first SIG subfield of the null data packet. The information bits of the first SIG subfield of the null data packet indicate, to a receiving device, a first physical layer (PHY) parameter value associated with the null data packet. The first PHY parameter value is not a length value. | 02-21-2013 |
20130177004 | INFORMATION BIT PADDING SCHEMES FOR WLAN - In a method for generating a data unit, a signal field is generated to include a first subfield having one of: a length indication to indicate a number of bytes in a data portion of the data unit, or a duration indication to indicate a number of OFDM symbols in the data portion of the data unit and a second subfield to indicate whether the first subfield includes the length indication or the duration indication. When the first subfield includes the length indication, one or more padding bits are added to a set of information bits according to a first padding scheme. When the first subfield includes the duration indication, one or more padding bits are added to the set of information bits to according to a second padding scheme. Padded information bits are encoded, and the data unit is generated to included the encoded information bits. | 07-11-2013 |
20130195092 | SYSTEMS AND METHODS FOR GENERATING PREAMBLE SYMBOLS IN COMMUNICATION SYSTEMS - A method for transmitting an 802.11ah packet is provided. A training field sequence is generated using control circuitry. A preamble for a packet is generated using the control circuitry. The preamble includes a training field symbol which includes the training field sequence. A portion of the training field sequence is within a plurality of guard tones of the training field symbol. The preamble is transmitted using transmit circuitry. | 08-01-2013 |
20130201835 | MULTI-CHANNEL WIRELESS COMMUNICATIONS - Systems and techniques relating to wireless communications are described. A described technique includes monitoring wireless communication channels, including a first channel and a second channel, to produce a monitoring output, determining a first transmission period for the first channel by applying a first waiting period duration and a second waiting period duration to the monitoring output, determining a second transmission period for the second channel by applying the first waiting period duration and the second waiting period duration to the monitoring output, causing, based on the first transmission period, a first transmission on the first channel to reserve the group of wireless communication channels; causing, based on the second transmission period, a second transmission on the second channel; and monitoring, after the end of the first transmission period, for an acknowledgement(s), An end of the second transmission period can be aligned with an end of the first transmission period. | 08-08-2013 |
20130259017 | Physical Layer Frame Format for WLAN - 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. | 10-03-2013 |
20140023092 | CYCLIC SHIFT DELAYS IN MULTI-USER PACKETS WITH RESOLVABLE VERY HIGH THROUGHPUT LONG TRAINING FIELDS (VHTLTFS) - A system including a stream generator module to generate a plurality of streams to be transmitted in a packet. The packet is to be transmitted to a plurality of client stations. First streams are designated for a first client station and include a plurality of training fields. Second streams are designated for a second client station and include the plurality of training fields. A cyclic shift delay module applies a plurality of cyclic shift delay values to the plurality of streams. First values from the plurality of cyclic shift delay values are respectively applied to the first streams. Second values from the plurality of cyclic shift delay values are respectively applied to the second streams. A mapping module spatially maps the plurality of streams subsequent to the cyclic shift delay module applying the cyclic shift delay values to the plurality of streams. | 01-23-2014 |
20140126659 | PARSING AND ENCODING METHODS IN A COMMUNICATION SYSTEM - In a method for generating a physical layer (PHY) data unit for transmission via a communication channel, a plurality of information bits to be included in the PHY data unit is received. A number of padding bits that need to be added to the information bits such that the information bits, after having been encoded, fill an integer number of orthogonal frequency division multiplexing (OFDM) symbols is determined. The number of padding bits is added to the information bits prior to encoding and the information bits are parsed to a number of encoders. The information bits are encoded to generate coded data bits. A last block of the data unit is encoded differently from the previous blocks. The PHY data unit to include the coded data bits is generated. | 05-08-2014 |
20140254414 | Compressed Feedback Format for WLAN - Channel data for a plurality of OFDM tones for one or more spatial or space-time streams are determined. A plurality of angle values associated with the one or more spatial or space-time streams and the one or more OFDM tones of the plurality of OFDM tones are determined. For each of the one or more spatial or space time streams, a per-tone signal to noise ratio (PT-SNR) associated with one or more OFDM tone of the plurality of OFDM tones is determined, and an average signal to noise ratio (avg-SNR) is determined by averaging signal to noise ratio (SNR) values corresponding to one or more OFDM tones of the plurality of OFDM tones. A feedback report is generated to include at least i) the plurality of angle values , ii) the PT-SNRs, and iii) the avg-SNR. | 09-11-2014 |
20150071366 | UPLINK TRAINING FOR MIMO IMPLICIT BEAMFORMING - In a method for beamforming in a multiple input multiple output (MIMO) communication system, a data unit is received from a communication device via a MIMO communication channel, and it is determined whether the data unit satisfies one or more selection criteria. Further, when it is determined that the data unit satisfies the one or more selection criteria, the data unit is selected to be used in developing a steering matrix for transmitting data units to the communication device. | 03-12-2015 |