基于软符号重构的迭代子载波间干扰补偿方法

摘要

脉冲熄灭是正交频分复用(orthogonal frequency division multiplexing,OFDM)接收机常用脉冲干扰抑制方法,但该方法将导致子载波间干扰(inter carrier interference,ICI),恶化OFDM接收机链路传输的可靠性.为克服脉冲熄灭OFDM接收机ICI的问题,提出基于软符号重构的迭代ICI抑制方法.接收机信道译码器输出的码字比特软信息交织后计算得到发送符号的软估计值,然后利用信道频率响应重构接收信号,最后对熄灭信号样值进行时域补偿.仿真结果表明,所提出方法可有效消除脉冲熄灭法产生的ICI,提高OFDM接收机链路传输的可靠性.%Pulse blanking is a widely used method to eliminate impulsive interference in orthogonal frequency division multiplexing (OFDM) receiver.However,the inter carrier interference (ICI) caused by pulse blanking heavily deteriorates the reliability of the OFDM system.To mitigate the adverse influence of ICI for the OFDM receiver,an iterative ICI mitigation method based on soft-symbol reconstruction is proposed.Firstly,the softsymbols are calculated based on the interleaved codeword bit soft-information of the codeword bit from the softdecoder.Then,the received signal is reconstructed with the soft-symbols and the frequency response of channel.Finally,the blanked samples are compensated with the reconstructed received signal and the position information of the blanked samples.Simulation results show that the proposed method can effectively suppress ICI and improve the reliability of the OFDM system.