Abstract: The present invention relates to methods of transmitting and receiving a frame, which are performed by a station operating in a power save mode in a wireless LAN system. The method includes: transmitting a poll frame requesting the transmission of a buffered frame to an access point AP, wherein the poll frame includes a sustain time field that indicates a service section; and receiving at least one buffered frame from the AP within the sustain time in response to the poll frame. A method is provided for transmitting and receiving a frame executed by a station (STA) operating in a power sub mode in a wireless LAN system. The method includes transmitting a first poll frame requesting the transmission of a buffered frame to an access point AP, receiving an acknowledgement ACK frame in response to the first poll frame, and receiving at least one buffered frame from the AP.

Abstract: Disclosed are a method and an apparatus for indicating a frame type using a physical layer convergence protocol header. A method for determining a frame type using a PLCP header may comprise: a step of demodulating a frame type contained in an SIG of the PLCP header so as to acquire information indicating a physical service data unit (PSDU) of a frame; and a step of acquiring frame information required for demodulating the frame contained in the SIG dependently on the information indicating PSDU. Thus, unnecessary information may not be additionally demodulated to thereby improve demodulation efficiency and reduce unnecessary power consumption.

Abstract: The present invention relates to a method for transmitting and receiving a frame performed by an AP in a wireless communication system. The method includes the steps of: transmitting a PST message providing instructions to transmit a frame to at least one STA; and receiving frames from a first STA and a second STA. The PST message includes first subband information indicating a first subband in which a first frame is transmitted from the first STA and second subband information indicating a second subband in which a second frame is transmitted from the second STA.

Abstract: A communication method based on identifying information assignment in a wireless local area network (WLAN) system, performed by a station (STA), is provided. The method includes receiving an identifier assignment message from an access point (AP), wherein the identifier assignment message comprises identifying information for the STA, and TIM offset information for a time point at which at least one traffic indication map (TIM) element for the STA starts to be transmitted; receiving a first TIM element from the AP at a time point indicated by the TIM offset information; determining whether the first TIM element comprises the identifying information; and receiving a first data frame from the AP if the first TIM element contains the identifying information.

Abstract: Disclosed are a link adaptation method and device in an active scanning method. The link adaptation method transmits a the probe request frame comprising null data packet announcement (NDPA) information elements, transmits a null data packet (NDP) frame comprising only a physical layer convergence protocol (PLCP) header after transmitting the probe request frame, and receives a the probe response frame comprising feedback information elements measured based on the NDP frame. Therefore, the invention is capable of improving data transmission efficiency by using a modulation coding scheme (MCS) suitable for a channel state from initial connection.

Abstract: The present invention relates to methods of transmitting and receiving a frame, which are performed by a station operating in a power save mode in a wireless LAN system. The method includes: transmitting a poll frame requesting the transmission of a buffered frame to an access point AP, wherein the poll frame includes a sustain time field that indicates a service section; and receiving at least one buffered frame from the AP within the sustain time in response to the poll frame. A method is provided for transmitting and receiving a frame executed by a station (STA) operating in a power sub mode in a wireless LAN system. The method includes transmitting a first poll frame requesting the transmission of a buffered frame to an access point AP, receiving an acknowledgement ACK frame in response to the first poll frame, and receiving at least one buffered frame from the AP.

Abstract: A method for communicating in a wireless local area network is provided. The method includes receiving allowed channel information from a second station, the allowed channel information indicating whether at least one channel is allowed for transmission, selecting, by the first station, at least one operating channel from the at least one allowed channel, and transmitting, by the first station, frames on the at least one selected operating channel. The allowed channel information comprises an allowed channel bitmap. Each bit of the allowed channel bitmap indicates each channel is allowed for the transmission.

Abstract: Provided is a method for transmitting a data unit in a wireless local area network system, according to one embodiment. The method comprises transmitting a signal field, transmitting a first data symbol for a first data field, and transmitting a second data symbol for a second data field. The signal field, the first data symbol, and the second data symbol are transmitted through a 1 MHz channel bandwidth having a band of 1 GHz or less. Two pilot tones are inserted to each of the first data symbol and the second data symbol.

Abstract: Method and device for discovering a service are provided. A responding device receives a service request frame including a first service identifier indicating a service queried by the requesting device. The responding device transmits a service response frame to indicate that the queried service is currently not available and a service announce frame follows on. The responding device determines whether the queried service is accepted or not during a pre-defined time after transmitting the service response frame.

Abstract: The present invention relates to methods of transmitting and receiving a frame, which are performed by a station operating in a power save mode in a wireless LAN system. The method includes: transmitting a poll frame requesting the transmission of a buffered frame to an access point AP, wherein the poll frame includes a sustain time field that indicates a service section; and receiving at least one buffered frame from the AP within the sustain time in response to the poll frame. A method is provided for transmitting and receiving a frame executed by a station (STA) operating in a power sub mode in a wireless LAN system. The method includes transmitting a first poll frame requesting the transmission of a buffered frame to an access point AP, receiving an acknowledgement ACK frame in response to the first poll frame, and receiving at least one buffered frame from the AP.

Abstract: Provided is a communication method by a station (STA) that operates in a power safe mode in a wireless LAN system. The method comprises: transmitting a probe request frame to an access point (AP), wherein the probe request frame includes system information identification information for identifying system information acquired by the STA; and receiving a probe response frame as a response to the probe request frame from the AP. The probe response frame includes a time stamp value related to the point of time of transmitting the probe response frame, and if it is determined, based on the system information identification information, that updated information which is not included in said acquired system information exists, the probe response frame further includes said updated information. Also provided is a communication method by an access point (AP) in a wireless LAN system.

Abstract: Disclosed are a method and an apparatus for indicating a frame type using a physical layer convergence protocol header. A method for determining a frame type using a PLCP header may comprise: a step of demodulating a frame type contained in an SIG of the PLCP header so as to acquire information indicating a physical service data unit (PSDU) of a frame; and a step of acquiring frame information required for demodulating the frame contained in the SIG dependently on the information indicating PSDU. Thus, unnecessary information may not be additionally demodulated to thereby improve demodulation efficiency and reduce unnecessary power consumption.

Abstract: Disclosed are method and device for indicating a PLCP header transmission mode. A method for generating a physical layer convergence protocol (PLCP) of a data frame can comprise the following steps: demodulating PLCP header mode information based on a scrambling sequence of the received frame or information elements included in the received frame; and generating a data frame including the PLCP header generated based on the PCLP header mode information. The PLCP header mode information comprises at least one indication from a space time block coding mode indication, a guard interval mode indication, and a repetition mode indication. The invention is capable of improving data transmission efficiency by adaptively determining a transmission mode of a PCLP header to a channel situation.

Abstract: In an aspect, a method of receiving a data unit, performed by an Access Point (AP), in a Wireless LAN (WLAN) system is provided. The method includes transmitting a signal protection frame, the signal protection frame comprising a group ID field indicating a Multiple Input Multiple Output (MIMO) transmission STA group including a first station (STA) and a second STA; and, a spatial stream field indicating a number of spatial streams allocated to each of member STAs included in the MIMO transmission STA group; receiving a first preamble for a first data unit from the first STA; receiving a second preamble for a second data unit from the second STA; and simultaneously receiving the first data unit from the first STA and the second data unit from the second STA.

Abstract: Provided is a method for transceiving data in a wireless LAN system on the basis of station (STA)-based service period scheduling. The method comprises entering an awake state, configuring a service period for transceiving an access point (AP) and data, transceiving the AP and the data during the service period, and entering a doze state when the service period ends.

Abstract: Disclosed are a method and a device for transmitting a data block. The method involves generating and transmitting a physical layer protocol data unit (PPDU) that includes a short training field, a long training field and a signal field. The signal field includes a frame type field that has a length of one bit and indicates whether the PPDU includes a control medium access control (MAC) frame. The device is capable of performing the method.

Abstract: Provided is a method for receiving a frame, which is to be performed by a station (STA) in a wireless LAN system. The method includes receiving a multicast frame from an access point (AP). The multicast frame includes a medium access control (MAC) header. The MAC header includes a transmitter address (TA) field and a receiver address (RA) field. The RA field includes a multicast association identifier for identifying an STA group including said STA.

Abstract: A communication method performed by a target station in a WLAN system is provided. The method includes receiving a relayed TIM message from a relay station, the TIM message comprising a relayed TIM field indicating whether there is buffered traffic intended to be transmitted from an AP to the target station, determining whether there is the buffered traffic based on the relayed TIM field, receiving a data frame related to the buffered traffic, if the relayed TIM field indicates that there is the buffered traffic, and switching to a doze state, if the relayed TIM field indicates that there is no buffered traffic. The relayed TIM field is determined based on a TIM element transmitted from the AP to the relay station. The TIM element is transmitted in a first period, and the relayed TIM message is transmitted in a second period.

Abstract: The present invention relates to a method and apparatus for transmitting channel parameter information. A method for transmitting a frame in consideration of a channel environment includes the steps of: receiving long training field (LTF) setting information from a station; creating a frame including an LTF, a plurality of divided data fields, and an additional LTF on the basis of the LTF setting information; and transmitting the frame, wherein the LTF positions are ahead of the plurality of divided data fields, the additional LTF positions are between or behind the plurality of divided data fields, and the LTF setting information can be created on the basis of the movement of the station. Therefore, channel estimation performance can be increased.

Abstract: Provided is a method for transceiving data in a wireless LAN system on the basis of a station (STA). The method comprises: receiving an allocation for an association ID (AID) by associating with an access point (AP); and exchanging data with the AP during the channel access period for an STA group comprising the STA. The STA group is grouped on the basis of the AID.