BICM-OFDM失配解调修正研究  

Mismatched LLR Correction for BICM-OFDM Systems with Imperfect Channel Estimation and Multiple Narrow Band Interference

作　　者：姚瑶[1] 赵骥[2] 许丁杰 张朝贤[3] 

机构地区：[1]华为技术有限公司,上海201206 [2]上海交通大学电子工程系,上海200240 [3]厦门大学嘉庚学院,福建厦门363105

出　　处：《通信技术》2017年第5期857-861,共5页Communications Technology

基　　金：国家863高科技计划(No.2014AA01A704)~~

摘　　要：考虑多路窄带干扰及非理想信道估计所造成的影响,采用常规的译码方法会使系统的信道适应力下降,降低与其他系统的兼容性,导致系统性能变差。因此,分析比特交织编码调制-正交频分复用(BICM-OFDM)系统中的解调失配现象,提出一种基于广义互信息(GMI)和对数似然比(LLR)的二维修正解调算法,并推导得到了基于信道转移概率的最佳LLR。理论分析及数值仿真结果表明,该修正解调算法与传统译码方法相比,可以在GMI和误码率等方面显著提高系统性能。Considering the effects of the multiple narrow band interference （NB1） and the imperfect channel estimation, and that with conventional channel adaptive decoding methods the system performance and the compatibility with other systems would be degraded, and for this reason, a novel two-dimension log-likelihood ratio （LLR） correction method based on the generalized mutual information （GMI） is proposed. In addition, the optimal LLR based on channel transition probability is also derived. Simulation results show that the correction algorithm could improve the performance significantly in terms of GMI and bit error ratio.

关 键 词：比特交织编码调制-正交频分复用 适配解码度量 非理想信道估计 窄带干扰 广义互信息 

分 类 号：TN911.3[电子电信—通信与信息系统]