基于遗传算法的短波OFDM信道估计导频优化方案  

Genetic Algorithms Based Optimization Scheme of Pilot Pattern for HF Channel Estimation in OFDM System

作　　者：韦世红[1] 孟婷婷[1] 唐宏[1] 

机构地区：[1]重庆邮电大学移动通信技术重庆市重点实验室,重庆400065

出　　处：《电视技术》2015年第19期47-50,62,共5页Video Engineering

基　　金：国家留学基金项目(201407845013);应急通信重庆市重点实验室开放课题;重庆市科委重点实验室专项;重庆邮电大学自然科学基金项目(A2011-51)

摘　　要：短波信道具有时域稀疏性,压缩感知理论应用于短波OFDM信道估计可以改善估计性能以及减少导频开销。然而信道估计性能和信道的可恢复性都与导频的放置有着密切关系,为了进一步提高信道重构精度,以最小化测量矩阵的互相关为导频优化目标,提出一种基于遗传算法的导频优化方案,并设计了相应的交叉算子和变异算子,以产生新个体,保证种群的多样性。仿真结果表明,相比随机搜索,该方案可以得到更小的互相关值、更高的重构精度以及更高的频带利用率。Short wave （HF） channel is a kind of time domain sparse channels, the application of the recent theory of compressed sensing has proved its efficiency to both ameliorate the estimation accuracy and reduce the transmitted overhead. The performance and uniqueness guarantee of recovery remain however closely related to the pilots placement. In order to further enhance the performanee of the estimation, the deterministic design of pilot pattern is investigated based on minimizing the coherence of the measurement matrix, then a pilot design scheme is proposed based on genetic algorithms, and a suitable crossover operator and mutation operator are designed to generate new individuals. Simulation results show that compared with the random search, the proposed scheme can get a smaller cross-correlation value, higher reconstruction accuracy and higher spectral efficiency.

关 键 词：压缩感知 OFDM 短波信道估计 导频图案设计 最小互相关 遗传算法 

分 类 号：TN929.5[电子电信—通信与信息系统]