Optimization Algorithm for DOA Estimation of a Shallow Sea Target Based on Active Time Reversal

基于主动时反的浅海目标DOA估计优化算法

¹ School of Marine Science and Technology, Northwestern Polytechnic University, Xi'an 710072, China
² School of Engineering, Xi'an International University, Xi'an 710077, China
³ China Shipbuilding Industry Corporation, Beijing, 100097, China

Received: 9 May 2017

Abstract

Time reversal technique is applied to the DOA estimation of a shallow sea target, and a method based on active time reversal (ATR) is proposed to achieve correct estimation under multipath and low signal-to-noise (SNR) conditions. Combining the classical ray theory with array signal processing theory, the conventional multipath DOA estimation model based on uniform line array and the ATR-based DOA estimation model are set up respectively. The Capon algorithm is employed to simulate the models and compare it with conventional one. The simulation results show that the ATR-based estimation model can better estimate the azimuth angle of the target than the conventional counterpart, provide higher resolution and better suppress side lobes with the same signal-to-noise ratio (SNR), especially the low SNR.

摘要

将时反技术应用到浅海目标DOA估计中，提出基于主动时间反转（active time reversal，ATR）的浅海目标DOA估计优化方法，可有效解决多径、低信噪比条件下的目标DOA估计问题。采用经典射线模型，结合阵列信号处理理论，建立了基于均匀线列阵的常规多径DOA估计模型和主动时反多径DOA估计模型，利用Capon算法对所建模型进行了仿真验证，并做了对比分析。仿真结果表明：在低信噪比情况下，主动时反方法可以更好地估计出目标的角度，其分辨率更高，抑制旁瓣的能力更强。