Abstract: A method of transmitting a training signal in a Wireless Local Area Network (WLAN) system includes generating one or more first training signals for a first destination station and one or more second training signals for a second destination station by applying a mapping matrix P to a training signal generation sequence, mapping the first training signals and the second training signals to a plurality of antennas according to an antenna mapping matrix, and performing Inverse Fast Fourier Transform (IFFT) on each of the first training signals and the second training signals mapped to the plurality of antennas and transmitting the training signals through the plurality of antennas.

Abstract: A method of receiving a packet in a wireless local area network system includes receiving, from an access point (AP), a packet comprising a data field and a first signal field including a first field, a second field, and a third field, wherein the packet is generated for a single receiving station or a plurality of receiving stations; and processing the packet based on the first signal field, wherein the first field indicates a group ID of the single receiving station or the plurality of receiving stations and whether the packet is generated based on a single user transmission scheme or a multi user transmission scheme, wherein, for the single user transmission scheme, at least one pre-determined value of the first field is used to indicate that the packet is generated based on the single user transmission scheme.

Abstract: A method of transmitting a data frame by a station in a wireless local area network (WLAN), A station obtains a transmission opportunity (TXOP) for a bandwidth. The TXOP indicates an interval of time during which the station has a right to initiate frame exchange sequences onto a wireless medium. The station selects a transmit bandwidth parameter of a non-initial data unit of a plurality of data units from available bandwidth parameters. The available bandwidth parameters include a first available bandwidth parameter which is same as a transmit bandwidth parameter of a preceding data unit of the plurality of data units and a second available bandwidth parameter which is narrower than a transmit bandwidth parameter of the preceding data unit. The station transmits, during the TXOP, the non-initial data unit according to the transmit bandwidth parameter of the non-initial data unit.

Abstract: A method and a wireless apparatus for power saving in a wireless local area network are discussed. The method according to an embodiment includes receiving a frame including a signal field from a transmitting device. The signal field includes a number indicator and a power saving indicator. The number indicator indicates a number of spatial streams for a corresponding recipient, and the power saving indicator indicates that the transmitting device allows the wireless device to enter a doze state during a transmission opportunity (TXOP). The method further includes entering the doze state until the end of the TXOP if the power saving indicator indicates an allowance of entering the doze state during the TXOP, and the number of spatial streams to be received by the wireless device is equal to zero.

Abstract: A method for transmitting data in a wireless local area network, the method comprising: receiving, by a receiving station, a physical layer protocol data unit (PPDU) from a transmitting station, the PPDU including a signal-A field, the signal-A field including a bandwidth in which the PPDU is received, decoding the PPDU, wherein, when the PPDU is used for single-user (SU) transmission, the PPDU is decoded with assuming that the PPDU does not include a signal-B field, and, when the PPDU is used for multi-user (MU) transmission, the PPDU is decoded with assuming that the PPDU include the signal-B field, and wherein the signal-B field includes a modulation and coding scheme (MCS) used for the receiving station.

Abstract: A method of transmitting a packet in a wireless local area network system. The method is performed by a transmitting station and includes generating a packet including at least one spatial stream and first control information including a first field and a second field, and transmitting the packet to at least one receiving station. The first field indicates a group ID of the at least one receiving station and whether the packet is generated based on a single user transmission scheme or a multi user transmission scheme. Content of the second field is determined based on whether the packet is generated based on the single user transmission scheme or the multi user transmission scheme, the second field indicates a modulation and coding scheme (MCS) index used for the packet if the packet is generated based on the single user transmission, and the second field indicates an encoding scheme applied to the at least one receiving station if the packet is generated based on the multi user transmission scheme.

Abstract: A method of transmitting a data frame by a transmitter in a WLAN system is provided. The method includes generating a data block including at least one data units respectively transmitted through at least one or more spatial streams to at least one receiver, transmitting first control information to the at least one receiver, transmitting second control information to each receiver, and transmitting the data block to the at least one receiver. The first control information includes a length indicator for the data block, a MIMO indicator indicating whether the data block is for SU-MIMO or MU-MIMO, and a spatial stream indication field including information about the number of the spatial streams. The second control information includes a FEC coding field indicating an encoding scheme applied to the data unit and an MCS field indicating an MCS applied to the data unit.

Abstract: A method for transmitting and receiving uplink signals using an optimized rank 3 codebook is disclosed. The optimized rank 3 codebook includes 6 precoding matrix groups, each of which has 1 variable having an amplitude of 1. Preferably, the optimized 4Tx rank 3 codebook has 12 precoding matrix, two precoding matrixes are selected from each the above 6 precoding matrix groups considering chordal distance and the number of precoding matrix.

Abstract: A method and a transmitting station for transmitting data in a wireless local area network are discussed. The method according to an embodiment includes generating a physical layer convergence procedure (PLCP) protocol data unit (PPDU), the PPDU including a Very High Throughput Signal (VHT-SIG) field and a PLCP Service Data Unit (PSDU); and transmitting the PPDU to a receiving station. The VHT-SIG field includes a class type and identification information, the class type indicates that the PPDU is transmitted by an access point (AP) or a non-AP station, the identification information includes a partial identifier formed from a Basic Service Set Identifier (BSSID), and the partial identifier has a length shorter than a length of the BSSID.

Abstract: A method for transmitting a sounding reference signal in a MIMO wireless communication system and an apparatus therefor are disclosed. The method for transmitting sounding reference signals (SRSs) in a MIMO wireless communication system comprises receiving sounding reference signal parameters from a base station; receiving information of the number of sounding reference signals which will be transmitted at a transmission time instant from the base station; if a plurality of sounding reference signals are provided, generating the sounding reference signals corresponding to each of the plurality of antennas by using the sounding reference signal parameters; and transmitting the generated sounding reference signals to the base station through their corresponding antennas at a specific transmission instant.

Abstract: A method for transmitting data in a wireless local area network, and a device therefore are discussed. The method according to one embodiment includes generating, by a transmitter, a very high throughput (VHT)-SIG-A field; generating, by the transmitter, a VHT-SIG-B field by applying a single column vector; and transmitting, by the transmitter, a physical layer protocol data unit (PPDU) to a receiver, the PPDU including the VHT-SIG-A field and the VHT-SIG-B field. The single column vector is obtained from a number of spatial streams for the receiver.

Abstract: A method and terminal are described for allocating resources for transmitting a signal in a multiple-input multiple-output (MIMO) wireless communication system. An uplink signal is transmitted using L layers at a terminal in a multiple-input multiple-output (MIMO) wireless communication system. Modulation symbols are generated by modulating output bit sequences of an interleaver matrix by a unit of log2 Q bits, where Q is a modulation order. Each of the output bit sequences has a size of L·log2 Q bits. The modulation symbols are mapped to the L layers and transmitted by using the L layers. The output bit sequences are generated by reading out entries of the interleaver matrix, column by column.

Abstract: A method of transmitting a data frame by a transmitter in a WLAN system is provided. The method includes generating a data block including at least one data units respectively transmitted through at least one or more spatial streams to at least one receiver, transmitting first control information to the at least one receiver, transmitting second control information to each receiver, and transmitting the data block to the at least one receiver. The first control information includes a length indicator for the data block, a MIMO indicator indicating whether the data block is for SU-MIMO or MU-MIMO, and a spatial stream indication field including information about the number of the spatial streams. The second control information includes a FEC coding field indicating an encoding scheme applied to the data unit and an MCS field indicating an MCS applied to the data unit.

Abstract: A method and a wireless apparatus for power saving in a wireless local area network are discussed. The method according to an embodiment includes receiving a frame including a signal field from a transmitting device. The signal field includes a number indicator and a power saving indicator. The number indicator indicates a number of spatial streams for a corresponding recipient, and the power saving indicator indicates that the transmitting device allows the wireless device to enter a doze state during a transmission opportunity (TXOP). The method further includes entering the doze state until the end of the TXOP if the power saving indicator indicates an allowance of entering the doze state during the TXOP, and the number of spatial streams to be received by the wireless device is equal to zero.

Abstract: A method and a device for reporting a modulation and coding scheme (MCS) feedback in a wireless local area network are provided. A responding station receives, from a requesting station, a requesting Physical layer Protocol Data Unit (PPDU) for requesting a MCS feedback via a plurality of spatial streams. A recommended MCS is estimated under an assumption that the requesting station will transmit at least one first spatial stream among the plurality of spatial streams used for the requesting PPDU, The responding station transmits, to the requesting station, the MCS feedback including a recommended MCS field indicating the recommended MCS and a recommended stream field indicating a number of at least one recommended spatial stream. A number of the at least one first spatial stream used for estimating the recommended MCS is equal to the number of the at least one recommended spatial stream.

Abstract: A method for transmitting a sounding reference signal in a MIMO wireless communication system and an apparatus therefor are disclosed. The method for transmitting sounding reference signals (SRSs) in a MIMO wireless communication system comprises receiving sounding reference signal parameters from a base station; receiving information of the number of sounding reference signals which will be transmitted at a transmission time instant from the base station; if a plurality of sounding reference signals are provided, generating the sounding reference signals corresponding to each of the plurality of antennas by using the sounding reference signal parameters; and transmitting the generated sounding reference signals to the base station through their corresponding antennas at a specific transmission instant.

Abstract: A method of transmitting data in a wireless local area network; and a device therefore are discussed. The method according to one embodiment includes generating, by a transmitting station, a physical layer convergence procedure (PLCP) protocol data unit (PPDU), the PPDU including a signal field and a data field; and transmitting, by the transmitting station, the PPDU to the receiving station. The signal field includes a class type indicating whether a transmission type of the PPDU is an uplink transmission or a downlink transmission.

Abstract: A method and a radio apparatus for signal transmission in a Wireless Local Area Network (WLAN) system are discussed. The method according to an embodiment includes generating first and second very high throughput (VHT) fields including first and second control information, respectively; and transmitting a physical layer protocol data unit (PPDU) including the first and second VHT fields to at least one target station. The first VHT field includes an indicator indicating whether the PPDU is to be transmitted by using a single-user multiple input multiple output (SU-MIMO) scheme or a multi-user multiple input multiple output (MU-MIMO) scheme.

Abstract: A method is provided for transmitting data in a wireless local area network. A transmitter generates an encoded data unit by performing a channel coding to transmission data to be included in a data field of a physical layer protocol data unit (PPDU). The transmitter generates at least one spatial block by re-arranging the encoded data unit, and divides each spatial block of at least one spatial block into two frequency segments. A bandwidth of each frequency segment is half of a bandwidth of the each spatial block. The transmitter interleaves the two frequency segments to generate a first interleaved segment and a second interleaved segment, respectively, and generates first and second mapped sequences by respectively mapping the first and second interleaved segments into a signal constellation. The transmitter performs an Inverse Discrete Fourier Transform (IDFT) on the first and second mapped sequences to generate and transmit a transmission signal.

Abstract: A method of power saving in a wireless local area network, and a wireless apparatus therefore are discussed. The method according to one embodiment includes acquiring a transmission opportunity (TXOP), receiving a signal field, the signal field including a group identifier, a number indicator and a power saving indicator, the group identifier indicating a group of recipients, the number indicator indicating a number of spatial streams, the power saving indicator indicating that the transmitting device allows the wireless device to enter a doze state. The method according to the embodiment further includes entering the doze state until the end of the TXOP if the power saving indicator indicates an allowance of entering the doze state during the TXOP, the wireless device is a member of the group of recipients, and the number of spatial streams to be received by the wireless device is equal to zero.