一种适用于OFDM系统的新型混合ARQ方案

A Novel Hybrid ARQ Scheme for OFDM Systems

提出了OFDM系统下一种变化交织方式的ARQ方案.利用高阶调制中映射到同一调制符号的各比特性能不同和超过相干带宽的OFDM子载波衰落相互独立的特性,数据重传时改变比特级交织方式,从而改变各次重传编码码流的顺序,使得同一比特得以被映射到不同的子载波和调制符号位置,取得分集效果.重传数据在比特级最大比合并.

A novel Hybrid ARQ scheme for orthogonal frequency division multiplexing (OFDM) systems is proposed. The scheme exploits the property of high level modulation that the performance of different bits mapped to the same modulation symbol is different, and the property of the multipath channel that the fading between any pair of OFDM subcarriers is independent, provided that the frequency interval is wider than channel's coherent bandwidth. In the retransmission of one data packet, the bit level interleaving mode is changed,so that the transmission order is changed, and the packet is maximum ratio combined at the bit level.