城市建筑阴影区动目标定位

Moving Target Localization in Building Shadow Areas

  • 摘要: 城市环境中建筑林立,互相遮挡,对建筑阴影区内目标进行探测是现代雷达面临的重要挑战,其主要原因是由于墙角等遮挡导致回波中缺乏直达波信号。为解决此问题,该文提出一种基于多径反射信号的建筑阴影区动目标定位算法。首先,利用线性调频连续波(Linear Frequency Modulated Continuous Wave, LFMCW)信号的距离-速度高分辨特性,设计了基于快速傅里叶变换(Fast Fourier Transform, FFT)与频谱分析的动目标相对距离-速度估计方法;其次,通过探索多径信号传播规律与建筑布局关系,设计了基于分布式探测架构的动目标绝对距离-速度估计方法;最后,利用雷达和建筑布局之间的几何关系,完成阴影区动目标绝对位置与速度估计,实现阴影区动目标定位。为验证所提方法效果,该文针对城市建筑阴影区场景下的运动目标设计了大量仿真实验。仿真结果表明,该算法对建筑阴影区运动目标具有很高的定位精度,有力增加了雷达的探测范围,展现了利用多径信号提升雷达探测效费比的巨大潜力。

     

    Abstract: ‍ ‍Urban environments are typically comprised of a variety of buildings, which obstruct each other and produce multiple building shadow areas. Detecting targets within these shadow areas is very challenging for radar systems because of the lack of line-of-sight signals owing to blockage by buildings. To address this issue, this study proposes a novel method to locate moving targets within building shadow regions based on multipath reflection signals. First, fast Fourier transform (FFT) and spectral analysis are jointly used to estimate the relative distance and velocity of the targets based on the high-resolution abilities of linear frequency modulated continuous wave (LFMCW) signals in terms of distance and velocity. Second, by exploring the relationship between the multipath signal propagation law and building layout, the absolute distance and velocity of the moving targets are further estimated by leveraging a distributed radar architecture. Finally, utilizing the geometric relationship between the radar system and building layout, the absolute position and velocity of the targets within the shadow regions are estimated, enabling the localization of moving targets. To validate the performance of the proposed approach, extensive simulation experiments were conducted for targets with different moving speeds and directions. The simulation results demonstrate that the proposed method can achieve high accuracy in localization of moving targets in building shadow regions, regardless of the moving speeds and directions. This significantly increases the detection coverage area and demonstrates potential for improving the detection effectiveness-cost ratio of radar systems by utilizing multipath signals.

     

/

返回文章
返回