面向浅海水声通信的TB-GOMP信道估计算法  

TB-GOMP channel estimation algorithm for shallow underwater acoustic communication

作　　者：孟熹亚 刘增力[1] MENG Xiya;LIU Zengli(Faculty of Information Engineering and Automation,Kunming University of Science and Technology,Kunming 650504,China)

机构地区：[1]昆明理工大学信息工程与自动化学院,昆明650504

出　　处：《兵器装备工程学报》2023年第5期223-229,共7页Journal of Ordnance Equipment Engineering

基　　金：国家自然科学基金项目(61271007)。

摘　　要：针对广义正交匹配追踪(generalized orthogonal matching pursuit,GOMP)算法复杂度较高、估计误差偏大、所需导频数过多、估计性能过度依赖原子选择数且未充分考虑噪声情况的问题,提出基于原子门限和回溯的广义正交匹配追踪(generalized orthogonal matching pursuit algorithm based on atomic threshold and backtracking,TB-GOMP)算法,并将其应用于水声正交频分复用(orthogonal frequency division multiplexing,OFDM)系统的压缩感知信道估计框架中。所提算法从多角度对GOMP算法进行改进,首先提出合理的原子门限,对原子精细筛选,利用原子门限不仅可以提高支撑集可靠性,还能通过降低运算复杂度缩短运行时间;其次,引入回溯思想消除算法中包含的误选原子,提高信道估计精度;最后,充分考虑到噪声因素,将迭代停止条件设置为噪声的L 2范数。多组实验结果表明所提算法在噪声环境下能有效估计浅海水声信道,并且在估计精度、运行时间、频谱节约度、稳健性等方面相较于对比算法具有明显优势。Aiming at the problems of generalized orthogonal matching pursuit(GOMP)algorithm,including high complexity,large estimation error,an excessive number of required pilots,over-dependence of estimation performance on atomic selection numbers and insufficient consideration of noise,this paper proposes a GOMP algorithm based on atomic threshold and backtracking(TB-GOMP).The proposed algorithm is also applied to the compressed sensing channel estimation framework of the underwater acoustic orthogonal frequency division multiplexing(OFDM)system.It improves the GOMP algorithm from multiple perspectives as well.Firstly,a reasonable atomic threshold is proposed for precisely screening atoms.Using the atomic threshold not only improves the support set reliability but also shortens the running time by reducing the complexity of operations.Secondly,the idea of backtracking is introduced to eliminate the misselected atoms contained in the algorithm to improve channel estimation accuracy.Finally,through an adequate consideration of noise,the iteration stop condition is set to the L 2 norm of the noise.The multiple experiment results demonstrate that the proposed algorithm can effectively estimate shallow underwater acoustic channels in a noisy environment,and has obvious advantages over the comparison algorithm in estimation accuracy,running time,spectrum saving,robustness and other aspects.

关 键 词：TB-GOMP OFDM 信道估计 浅海水声信道 

分 类 号：TJ617[兵器科学与技术—武器系统与运用工程]