DCO-OFDM系统TFI-SLM峰均比抑制算法

TFI-SLM peak-to-average ratio suppression algorithm in DCO-OFDM system

过高的峰均功率比(PAPR)造成的非线性失真是直流偏置光正交频分复用(DCO-OFDM)技术亟待解决的问题之一。针对该问题,设计了一种基于时频交织(TFI)和选择映射法(SLM)的TFI-SLM峰均比抑制算法。该算法通过先对输入信号进行TFI,降低输入信号的自相关性,再利用小m序列产生随机相位因子对变换后的信号进行选择性映射。仿真结果表明:与传统算法相比,该算法不仅避免了发送过多的相位因子序列冗余信息,并且互补累积分布函数(CCDF)值为10-5时,PAPR比原始DCO-OFDM系统降低了2.8 dB。

Non-linear distortion caused by excessively high peak-to-average power ratio(PAPR)is one of the problems to be solved urgently in direct-current biased optical orthogonal frequency division multiplexing(DCO-OFDM)technology.Aiming at this problem,an algorithm based on time frequency interleaving(TFI)and selection mapping(SLM)which called TFI-SLM peak-to-average ratio suppression algorithm is designed.This algorithm firstly performs TFI on the input signal to reduce the autocorrelation of the input signal,and then uses a small m sequence to generate a random phase factor to selectively map the transformed signal.Simulation results show that compared with the traditional algorithm,the algorithm not only avoids sending too much redundant information of phase factor sequence,but also reduces PAPR by 2.8 dB when the complementary cumulative distribution function(CCDF)value is 10-5.