最小均方误差自适应时延估计算法研究

发布时间：2018-06-02 03:24

本文选题：无源时差定位 + 二相编码信号　；参考：《西安电子科技大学》2014年硕士论文

【摘要】：无源时差定位以其作用距离远、隐蔽性好等特点在电子战系统中占有越来越重要的地位。无源时差定位的精度直接由时延估计的性能决定。自适应时延估计较少依赖信号与噪声的统计先验知识,更加适用于无源时差定位的环境。因此,对自适应时延估计方法的研究具有重要的理论意义与实用价值。本文研究最小均方误差准则下一般自适应时延估计方法与基于信号循环平稳性的自适应时延估计方法应用于二相编码信号时的性能。在分析一般自适应时延估计方法的估计精度、收敛速度以及时间复杂度的基础上,重点研究基于信号循环平稳性的自适应时延估计方法。针对二相编码信号的带限非平稳特性,在传统型信号循环平稳性算法基础上,本文提出了一种基于信号循环平稳性的约束型自适应时延估计算法,以解决传统型循环平稳算法不能直接估计整数时延与应用插值法导致的复杂度高的问题。理论分析与仿真结果表明,本文所提出的基于信号循环平稳性的约束型自适应时延估计算法在不损失估计精度与收敛速度的前提下,其时间复杂度是最低的,是现存循环平稳约束型算法的一半。针对一般的自适应时延估计方法与基于信号循环平稳性的自适应时延估计方法中涉及到的约束型算法存在局部最优点问题,本文通过传统型算法估计整数时延为约束类算法提供初值的方法,避免约束型算法收敛到局部最优点。
[Abstract]:Passive moveout location plays a more and more important role in EW system because of its long distance and good concealment. The accuracy of passive time difference location is directly determined by the performance of time delay estimation. Adaptive time delay estimation is less dependent on the statistical prior knowledge of signal and noise, so it is more suitable for passive time difference location. Therefore, the study of adaptive time delay estimation has important theoretical significance and practical value. In this paper, the general adaptive time delay estimation method based on minimum mean square error criterion and the adaptive time delay estimation method based on signal cyclic stationarity are studied. Based on the analysis of the estimation accuracy, convergence speed and time complexity of the general adaptive time delay estimation method, the adaptive time delay estimation method based on the signal cyclic stationarity is studied. Aiming at the band-limited nonstationarity of two-phase coded signals, a constrained adaptive time-delay estimation algorithm based on the cyclic stationarity of conventional signals is proposed. In order to solve the problem that the traditional cyclic stationary algorithm can not estimate the integer delay directly and the complexity caused by the application of interpolation method is high. Theoretical analysis and simulation results show that the proposed adaptive time delay estimation algorithm based on signal cyclic stationarity has the lowest time complexity without loss of estimation accuracy and convergence speed. Is half of the existing cyclic stationary constraint algorithm. In view of the local optimal problem in the conventional adaptive time delay estimation method and the adaptive time delay estimation method based on signal cyclic stationarity, the constrained algorithm has a local optimum problem. In this paper, we use the traditional algorithm to estimate the integer delay to provide the initial value for the constrained class algorithm, so as to avoid the constrained algorithm converging to the local optimum.
【学位授予单位】：西安电子科技大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TN911.7

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