降低OFDM系统峰均功率比的时频联合块交织方法

Time-frequency block interleaving schemes for PAPR reduction in OFDM systems

由于传统块交织方法是对单个正交频分复用(orthogonal frequency division multiplex,OFDM)信号进行块交织,所产生的候选信号间存在很大的相关性,在一定程度上影响了系统峰均功率比(peak-to-average power ratio,PAPR)性能的改善。针对传统块交织方法的这一局限性,提出了降低OFDM系统PAPR的时频联合块交织方法及其次优化方法。该方法将块交织扩展到一个时间片内的多个OFDM信号之间,增加了产生候选信号的自由度,降低了候选信号间的相关性。仿真结果表明,与传统块交织方法相比,在计算复杂度相同的情况下,所提出的时频联合块交织方法可以获得更优的PAPR性能。

As for one orthogonal frequency division multiplex （OFDM） signal, conventional block interleaving is implemented, but the correlation between two generated candidate signals is very strong, which degrades the improvement in peak-to-average power ratio （PAPR） reduction performance. Concerned on the limitation of conventional block inter- leaving, a time-frequency block interleaving scheme and its suboptimal scheme for PAPR reduction in OFDM systems were proposed. In proposed schemes, block interleaving was adopted among different OFDM signals in a timeslot, which improves the freedom of generating candidate signals and reduces the correlation between two different candidate signals. The simulation results show that, compared with conventional block interleaving, this schemes can obtain better PAPR reduction performance with the same computational complexity.