An adaptive HARQ scheme for COFDM system
Wang Guang-jia · Applied science and technology · 2010
The system which is made up of LDPC(low density parity check) codes and OFDM(orthogonal frequency division multiplexing) cannot get an ideal BER(bit error ratio) when confronted with bad communication channel.So an adaptive HARQ(hybrid automatic repeat request) scheme was proposed based on the COFDM(coding orthogonal frequency division multiplexing) system.It can make full use of the channel state information,which is obtained by the transmitter,to adaptively interweave the repeatedly transmitted symbols to bring down the channel influence on the same bit,and thereby to bring down the BER of the receiver.Simulation results show that the proposed scheme can get an ideal BER through either Rician channel or Gaussian channel.