基于gOMP算法的FBMC水声通信信道估计方法

FBMC underwater acoustic communication channel estimation method based on gOMP algorithm

传统基于训练序列及块状导频结构的滤波器组多载波(Filter Bank Multicarrier,FBMC)信道估计方法花费额外的频谱资源,这在频谱资源较为紧张的水声通信环境中具有一定的局限性。针对这一问题并结合水声信道稀疏性的特点,文章提出了一种基于压缩感知的离散导频结构FBMC信道估计方法。首先基于等效导频能量最大化的思想,设计了一种新的离散导频结构来解决FBMC系统信道估计时存在的固有虚部干扰问题;然后配合该结构,提取出导频处的接收信息并利用重构效果优良的压缩感知gOMP算法对水声信道进行重构。该方法在保证水声信道估计精度的同时有效提高了FBMC系统的频谱利用率,改善了水声通信的性能。仿真结果表明,文中所提方法相较于传统方法在估计精度和频谱利用率方面具有一定的优越性。

The traditional filter bank multi-carrier(FBMC)channel estimation method based on training sequence and block pilot structure spends additional spectrum resources,which leads to certain limitations of applying this method in the underwater acoustic communication environment where spectrum resources are limited.To solve this problem and considering the sparsity of underwater acoustic channel,a channel estimation method of FBMC with discrete pilot structure based on compressed sensing is proposed in this paper.Firstly,based on the idea of equivalent pilot energy maximization,the discrete pilot structure is designed reasonably to solve the problem of inherent imaginary part inter-ference in channel estimation of FBMC system.Then with this structure,the received information at pilot is extracted and the compressed sensing gOMP algorithm with good reconstruction effect is used to reconstruct the underwater acoustic channel.This method not only ensures the accuracy of channel estimation,but also effectively improves the spectrum utilization of FBMC system,which greatly improves the performance of underwater acoustic communication.The simulation results show that the proposed method is superior to the traditional methods in estimation accuracy and spectrum utilization.