A wireless data transmitting device in a wireless audio/video, AV, system, the device comprising: a plurality of transmit antennas (1150-1, 1150-2); a communication circuit which performs a multiple input multiple output, MIMO, beamforming procedure including an individual transmit, Tx, sector sweep, an individual receive, Rx, sector sweep and a single user, SU,-MIMO procedure, and transmits a physical layer protocol data unit, PPDU, frame to a wireless data receiving device through first and second transmit antennas; and a processor coupled with the communication circuit and configured to generate the PPDU frame, wherein the individual Tx sector sweep includes first and second sector sweeps, wherein the first sector sweep is performed for the first and second transmit antennas in a first sweep unit, wherein the second sector sweep is performed for the first and second transmit antennas in a second sweep unit, wherein K candidate Tx sectors for each of the first and second transmit antennas is derived as a result of the individual Tx sector sweep, wherein the individual Rx sector sweep includes third and fourth sector sweeps, wherein the third sector sweep is performed for first and second receive antennas in the first sweep unit, wherein the fourth sector sweep is performed for the first and second receive antennas in the second sweep unit, wherein J candidate Rx sectors for each of the first and second receive antennas is derived as a result of the individual Rx sector sweep, wherein the first and second transmit antennas operate in a quasi-omni antenna mode during which the individual Rx sector sweep is performed, wherein the SU-MIMO procedure determines an optimal Tx-Rx sector combination from the K candidate Tx sectors and the J candidate Rx sectors. a plurality of transmit antennas (1150-1, 1150-2); a communication circuit which performs a multiple input multiple output, MIMO, beamforming procedure including an individual transmit, Tx, sector sweep, an individual receive, Rx, sector sweep and a single user, SU,-MIMO procedure, and transmits a physical layer protocol data unit, PPDU, frame to a wireless data receiving device through first and second transmit antennas; and a processor coupled with the communication circuit and configured to generate the PPDU frame, wherein the individual Tx sector sweep includes first and second sector sweeps, wherein the first sector sweep is performed for the first and second transmit antennas in a first sweep unit, wherein the second sector sweep is performed for the first and second transmit antennas in a second sweep unit, wherein K candidate Tx sectors for each of the first and second transmit antennas is derived as a result of the individual Tx sector sweep, wherein the individual Rx sector sweep includes third and fourth sector sweeps, wherein the third sector sweep is performed for first and second receive antennas in the first sweep unit, wherein the fourth sector sweep is performed for the first and second receive antennas in the second sweep unit, wherein J candidate Rx sectors for each of the first and second receive antennas is derived as a result of the individual Rx sector sweep, wherein the first and second transmit antennas operate in a quasi-omni antenna mode during which the individual Rx sector sweep is performed, wherein the SU-MIMO procedure determines an optimal Tx-Rx sector combination from the K candidate Tx sectors and the J candidate Rx sectors.