Method and apparatus for transmitting plcp frame in wireless local area network system

A device configured for receiving data in a wireless local area network, the device comprising:

• a first interface for implementing a medium access control (MAC) layer;
• and
• a second interface for implementing a physical layer and configured to:
• receive a signal field that is mapped onto a first binary phase shift keying (BPSK) constellation;
• receive a first Very High Throughput Signal (VHT-SIG) field that is mapped onto the first BPSK constellation;
• and
• receive a second VHT-SIG field that is mapped onto a second BPSK constellation;
• wherein the second BSPK constellation is rotated by 90° counter-clockwise relative to the first BPSK constellation, and
• wherein the first VHT-SIG field includes an indicator indicating Single User-Multiple Input Multiple Output (SU-MIMO) transmission or multi user-MIMO (MU-MIMO) transmission, and the second VHT-SIG field includes a cyclic redundancy check (CRC) for the first and second VHT-SIG fields.