A communication system is provided. A first communications device transmits at least one first message including predetermined bit sequences. A second communications device determines one or more antenna weighting vectors (AWVs) and one or more bitloading vectors (BLVs) by using the first message in accordance with a predetermined rule and transmits a second message including information pertinent to the AWVs and the BLVs to the first communications device. The first communications device further communicates with the second communications device about an AWV selected from the AWVs and the first and second communications devices apply the selected AWV to the corresponding antennas before exchanging data. The data includes a header carrying information pertinent to a BLV selected from the BLVs used to encode the data and a payload is transmitted to the second communications device. The second communications device decodes the data in accordance with the selected BLV.