雷达中时延估计的新方法

A New Method of The Delay Estimation in Radar

对超宽带冲击雷达（Ｕｌｔｒａ－Ｗｉｄｅｂａｎｄ Ｉｍｐｕｌｓｅ Ｒａｄａｒ）目标检测和目标特征提取是超宽带冲击雷达系统研究的关键技术之一。在常规窄带雷达中，这些问题都是以傅里叶分析技术为基础进行处理的。而超宽带冲击雷达目标回波是瞬态信号，传统的傅氏方法在分析这类信号时有很大的局限性．小波变换由于其在时频域里良好的局部化特性，在超宽带雷达信号处理中具有重要的应用价值。本文结合国防“八五”预研项目“冲击雷达反隐身机理与关键技术研究”课题，考虑了在噪声环境下雷达时延估计方法。源信号是一个确知的、非稳态高斯过程，提出了用小波去噪法得到延时估计的新方法。这种方法以很高的概率整体收敛，而且计算经济。仿真计算结果显示了它比惯用的直接相关方法有更小的均方误差。

It's one of key techniques for Ultra-Wideband(UWB) Impulse radar to detect targets,and to ex- tract and describe th features of targets. These problems are carried out in narrow radar based on Fourier trans- form. It is difficult for Fourier techique to analyze UWB radar returns because the UWB signals are transient A new approach of wavelets transform s good property of 'Time-frequency localization'. Combining with the re- search subject' Them research of mechanism of anti-stealth targets, and of key techniques of Impulse radar, this paper considers the tme delay estimation problem under noisy environment. The source signal is assumed to be deterministic rather than stationary Gaussian process. A new time delay estimation method is proposed via wavelet denoising. The new method is verified to be globally convergent with a high probability and is computationally effi- cient. Simulation results show its superiority to other conventional methods like the commonly used General Gross Correlation method.