Patent ID: 8571057

Claim:
A method for a transmitter operating over at least two allocated subchannels in a communication system, each subchannel containing a plurality of Orthogonal Frequency Division Multiplexing (OFDM) subcarriers, the method comprising: transmitting, at a first transmission time to a receiver in the communication system, a first data packet over a first subchannel and a second data packet over a second subchannel; receiving a negative acknowledgement (NACK) from the receiver regarding the first data packet, the NACK indicating an error in the first data packet received by the receiver; and implementing a transmission swapping procedure with the first subchannel and the second subchannel at a second transmission time, the transmission swapping procedure enabling recovery of the first data packet by: re-transmitting the first data packet or its parity data over the second subchannel; and transmitting a third data packet originally scheduled for the second subchannel over the first subchannel, wherein the first subchannel and second subchannels have different spatial configurations and different pilot subcarrier compositions.