Abstract:
A method by which an STA transmits a multi-user (MU) frame in a wireless communication system, according to one embodiment of the present invention comprises the steps of: receiving, from an access point (AP), a second downlink frame including time synchronization information and frequency synchronization information; adjusting a time synchronization and a frequency synchronization by using the time synchronization information and the frequency synchronization information; receiving a third downlink frame including MU frame allocation information; and transmitting the MU frame according to the MU allocation information, wherein the time synchronization information is determined by comparing, to a reference value, a difference of measurement values relating to frames exchanged prior to the reception of the second downlink frame, and the reference value is a common value among STAs related to a multi-user transmission.
Abstract:
Provided are a method and apparatus for transmitting a feedback frame in a WLAN system. More specifically, the first wireless STA receives a feedback request field, including an LTF, from a second wireless STA. The first wireless STA configures feedback information about a wireless channel corresponding to a predetermined frequency band using the feedback request field. The first wireless STA transmits the feedback information to the second wireless STA.
Abstract:
When an AP (access point) performs sounding to transmit a frame to one or more STAs using a beamforming scheme in a wireless LAN (WLAN) system, the AP receives a beamforming feedback, which is generated based on measurement of a specific signal transmitted by the AP in a manner that the one or more STAs group a prescribed number of tones according to a tone grouping element (Ng). In this case, the Ng is configured by a multiple of 4.
Abstract:
Disclosed are a method and an apparatus for transmitting a data unit in a wireless local area network. A method for transmitting a data unit in a wireless local area network may comprise the steps of: an AP transmitting a first PPDU to a first STA by means of a first frequency resource in a time resource; and the AP transmitting a second PPDU to a second STA by means of a second frequency resource in a time resource overlapping the time resource, wherein the first frequency resource can be allocated to the first STA on the basis of the contentious or a non-contentious channel access of the first STA, and the second frequency resource can be allocated to the second STA on the basis of OFDMA.
Abstract:
Provided are a method and an apparatus for transmitting data in a wireless LAN. A transmitter receives, from an access point (AP), allocation information about at least one subband from among a plurality of subbands, and transmits a physical layer protocol data unit (PPDU) in the at least one allocated subband. A guard area is defined on both ends of at least any one of the plurality of subbands.
Abstract:
Provided are a method for transmitting data and a device using the same in a wireless LAN. A transmitter transmits a physical layer protocol data unit (PPDU) in a transmission bandwidth. The PPDU includes a first part to which a first fast Fourier transform (FFT) size is applied, and a second part to which a second FFT size is applied. The number of pilots of the second part is identical to the number of pilots of the first part, and the pilot frequency location of the second part is identical to the pilot frequency location of the first part.
Abstract:
Proposed herein is a LTF sequence that is used in a wireless LAN system. The proposed LTF sequence may correspond to a sequence for a second frequency band of a second wireless LAN system. The proposed sequence may be generated through a LTF sequence that is used in a first wireless LAN system, which is different from the second wireless LAN system. The LTF sequence of the first wireless LAN system may correspond to a sequence for a first frequency band, which is different from the second frequency band. A length of an IDFT/DFT period and a bandwidth of a transmission frequency that are applied to the LTF sequence of the first wireless LAN system are different from a length of an IDFT/DFT period and a bandwidth of a transmission frequency that are applied to the LTF sequence of the second wireless LAN system.
Abstract:
A method and apparatus for transmitting a frame on the basis of a sounding procedure is disclosed. The method for transmitting the frame on the basis of a sounding procedure in a wireless LAN may comprise the steps of: transmitting an NDPA frame to each of multiple STAs by an AP wherein the NDPA frame notifies of the transmission of NDP; transmitting the NDP to each of the multiple STAs by the AP; receiving, by the AP, multiple feedback frames transmitted through multiple transmission sources allocated to the multiple STAs in time sources overlapped by the multiple STAs, respectively; and transmitting, by the AP, multiple downlink frames to the multiple STAs respectively.
Abstract:
A method and apparatus for transmitting a signal from a base station to a first user equipment (UE) in a multiple-input multiple-output (MIMO) wireless communication system. Information on a movement speed of a second UE is acquired from the second UE. Channel information is determined based on the information on the movement speed. The channel information is previously measured by the first UE. A transmission and reception scheme is determined based on the determined channel information. At least one of the determined channel information or the determined transmission and reception scheme is transmitted to the second UE.
Abstract:
According to one embodiment, a method for a terminal to perform a hybrid automatic repeat request (HARQ) in a wireless access system that supports cooperative terminal communication includes allocating a second carrier from a base station through a first carrier, the first carrier being used for data transmission to the base station and the second carrier being used for data transmission to another terminal; receiving a preamble and configuration information on the second carrier from the base station; transmitting data to the other terminal in an uplink subframe of the second carrier on the basis of the received configuration information; and receiving acknowledgement (ACK) or non-acknowledgement (NACK) for the transmitted data from a downlink subframe of the second carrier related to the uplink subframe.