A method for supporting, by a first station, STA, beamforming with a second STA in a wireless local area network, WLAN, system, the method comprising: transmitting, to the second STA, a first frame to request beamforming training for two aggregated channels; transmitting a beam refinement protocol, BRP, packet comprising a Training field to the second STA, wherein channel measurement about the two aggregated channels is performed based on the BRP packet; and receiving, from the second STA, a second frame comprising feedback information measured, by the second STA, for each of the two aggregated channels based on the BRP packet, and further comprising an aggregation present field, wherein the aggregation present field has a value of '1', wherein the feedback information is channel information measured for each of the two aggregated channels based on the BRP packet, wherein the feedback information comprises signal-to-noise ratio, SNR, information, channel measurement information, enhanced directional multi-gigabit, EDMG, sector identity, ID, information, BRP countdown, CDOWN, information, and tap delay information per channel, which are measured for the two aggregated channels, wherein the SNR information and the channel measurement information per channel, which are measured for the two aggregated channels, are transmitted via a channel measurement feedback element comprised in the second frame, wherein the EDMG sector identity ID information, the BRP CDOWN information, and the tap delay information per channel, which are measured for the two aggregated channels, are transmitted via an EDMG channel measurement feedback element comprised in the second frame, wherein the first frame corresponds to a first BRP frame in which an Aggregation Requested field in a directional multi-gigabit, DMG, beam refinement element is set to 1, wherein the second frame corresponds to a third BRP frame in which an Aggregation Present field in the DMG beam refinement element is set to 1, and wherein the first frame and the second frame do not comprise the Training field. transmitting, to the second STA, a first frame to request beamforming training for two aggregated channels; transmitting a beam refinement protocol, BRP, packet comprising a Training field to the second STA, wherein channel measurement about the two aggregated channels is performed based on the BRP packet; and receiving, from the second STA, a second frame comprising feedback information measured, by the second STA, for each of the two aggregated channels based on the BRP packet, and further comprising an aggregation present field, wherein the aggregation present field has a value of '1', wherein the feedback information is channel information measured for each of the two aggregated channels based on the BRP packet, wherein the feedback information comprises signal-to-noise ratio, SNR, information, channel measurement information, enhanced directional multi-gigabit, EDMG, sector identity, ID, information, BRP countdown, CDOWN, information, and tap delay information per channel, which are measured for the two aggregated channels, wherein the SNR information and the channel measurement information per channel, which are measured for the two aggregated channels, are transmitted via a channel measurement feedback element comprised in the second frame, wherein the EDMG sector identity ID information, the BRP CDOWN information, and the tap delay information per channel, which are measured for the two aggregated channels, are transmitted via an EDMG channel measurement feedback element comprised in the second frame, wherein the first frame corresponds to a first BRP frame in which an Aggregation Requested field in a directional multi-gigabit, DMG, beam refinement element is set to 1, wherein the second frame corresponds to a third BRP frame in which an Aggregation Present field in the DMG beam refinement element is set to 1, and wherein the first frame and the second frame do not comprise the Training field.