When an STA receives first to fifth SSW frames (first training frames) transmitted from an AP, the STA measures reception quality thereof, and transmits a reception quality measurement result to the AP by incorporating the reception quality measurement result in an SSW-ACK frame (first feedback frame). In response, the AP selects a beam pattern satisfying a specific selection criterion based on the reception quality measurement result and employs the selected beam pattern as the transmission beam pattern for use in transmission to the STA.