强激光与粒子束, 2019, 31 (10): 103211, 网络出版: 2019-10-14
基于抛物方程的海陆环境信号时延与到达角估计
Estimation of time-delay and direction of arrival in complex sea and land environment using parabolic equation method
抛物方程 信号时延 到达角 海陆环境 蒸发波导 parabolic equation time-delay direction of arrival sea and land environment evaporation duct
摘要
针对复杂海陆环境中的无线信号传播预测问题, 研究了适用于抛物方程的信号时延与到达角估计方法。将自由空间中抛物方程轴向波前信号视为本地副本信号, 然后利用信号的自相关特性, 将接收信号与副本信号进行互相关运算, 最后通过相关函数的峰值检索, 得到脉冲信号在复杂环境中传播的附加时延。采用数值算例, 验证了该方法的正确性和有效性。此外, 采用多重信号分类算法, 由抛物方程构建接收阵列的协方差矩阵, 并对其进行特征值分解, 然后利用信号子空间和噪声子空间的正交性, 实现复杂环境中的信号到达角估计。仿真结果表明, 相比于传统的平面波谱方法, 该方法具有更高的多径分辨率。基于上述方法, 并结合数字地图, 在典型的海陆环境中进行了仿真实验, 分析了蒸发波导对脉冲信号传播时延和到达角的影响。
Abstract
Time-delay and direction of arrival are two important signal parameters in wireless positioning, radar detection, and target tracking applications. In this paper, a parabolic equation method is presented to simulate the propagation of pulse signals in the sea-to-land environment and to estimate the characteristic parameters of the signals considering irregular terrains and atmospheric refraction. A correlation function method is presented to extract the time-delay of the received signal from parabolic equation. Besides, a multiple signal classification algorithm is used to estimate the direction of arrival of signals, which provides a higher resolution compared with the traditional wave spectral method. Numerical examples are given to illustrate the correctness of the presented methods. Finally, with the presented methods, simulation experiments in a typical sea and land environment are presented to analyze the effects of evaporation duct on signal’s delay and direction of arrival.
张东民, 廖成, 邓小川, 冯菊. 基于抛物方程的海陆环境信号时延与到达角估计[J]. 强激光与粒子束, 2019, 31(10): 103211. Zhang Dongmin, Liao Cheng, Deng Xiaochuan, Feng Ju. Estimation of time-delay and direction of arrival in complex sea and land environment using parabolic equation method[J]. High Power Laser and Particle Beams, 2019, 31(10): 103211.