Method and device for performing beamforming training procedure considering millimeter wave band in wlan system

An apparatus comprising:

• at least one transceiver;
• and
• at least one processor connected to the at least one transceiver,
• wherein the at least one processor is configured to:
• by a first station (STA), identify information related to initiation of a sector sweep operation in a second operating frequency band in a first operating frequency band, the information including allocation information of a resource for the sector sweep operation;
• by the first STA, based on receiving a plurality of frames for the sector sweep operation in the resource from the second STA in the second operating frequency band, measure a best transmission (TX) sector of the second STA and perform a reception (RX) sector sweep of the first STA;
• by the first STA, transmit a feedback frame including identification information for the best TX sector to the second STA in the first operating frequency band;
• and
• by the first STA, receive a response frame to the feedback frame from the second STA in the first operating frequency band.

An apparatus comprising:

• at least one transceiver;
• and
• at least one processor connected to the at least one transceiver,
• wherein the at least one processor is configured to:
• by a second station (STA), identify, in a first operating frequency band, information related to initiation of a sector sweep operation in a second operating frequency band, the information including allocation information of a resource for the sector sweep operation;
• by the second STA, transmit, in the second operating frequency band, a plurality of frames for the sector sweep operation in the resource to a first STA;
• by the second STA, receive, in the first operating frequency band, a feedback frame including identification information for a best Tx sector of the second STA from the first STA;
• and
• by the second STA, transmit, in the first operating frequency band, a response frame to the feedback frame to the first STA.