A wireless communication device that is receiving a frame may determine whether the frame is an Up-Link Multi-User (UL MU) frame, receive the frame by performing a first procedure when the frame is determined to be the UL MU frame, and receive the frame by performing a second procedure when the frame is not determined to be the UL MU frame. Performing the first procedure may include performing a comparison of contents of a Legacy Signal (L-SIG) field of the frame to expected contents of the L-SIG field, performing a comparison of contents of a Signal A (SIG-A) field of the frame to expected contents of the SIG-A field, or both. The SIG-A field may be a High Efficiency SIG-A (HE-SIG-A) field.