For example, a first wireless station may be configured to transmit a beacon frame over a directional wireless communication band during a Beacon Transmission Interval (BTI), the beacon frame including a field including a type value to indicate a type of one or more wireless stations to respond to the beacon frame; and to process a Sector Sweep (SSW) frame from a second wireless station of a type corresponding to the type value during an Association Beamforming Training (A-BFT) period following the BTI.