Embodiments of the present invention provide an Access Point (AP) to transmit and receive RF signals in a wireless local area network (WLAN), comprising, a processor to process the RF signals, a scheduler to schedule data packets that may have differing lengths for transmission to selected mobile stations, a Radio Frequency (RF) transceiver to receive and transmit the RF signals using space-time channels, and a code rate adjuster to adjust a code rate of Forward Error-Correction (FEC) codes in the packets to fill the space-time channels.