复杂背景下目标散射信号测量与提取技术

在复杂环境条件下的宽带雷达目标散射特性测量中，场地周围环境产生的零多普勒杂波（ZDC）会严重影响目标测量数据的准确性。为了有效地抑制背景杂波、提高目标散射信号的测量精度，提出了一种基于最大概率提取技术。该技术首先通过方位滑窗平均得到每个频点的初始固定背景杂波估计，然后对每个频点的杂波初始估计进行统计直方图处理得到最大概率幅度统计量，并依据该统计量完成门限处理得到最终的杂波估计值，从而消除方位滑窗平均处理中的剩余目标信号分量、实现精确的背景提取与抵消。对典型目标的外场测量数据处理结果验证了本文方法的有效性。

Measurement and extraction technique of scattered signals for targets under complex background

Zero-Doppler clutter (ZDC) caused by the surrounding environment of an outdoor measurement field is one of the major factors which degrade the accuracy of the target scattering signatures in wideband radar cross section measurement. A new technique for ZDC estimation based on maximal probability is proposed to effectively suppress background clutter and improve the measurement uncertainty. In this technique, an initial ZDC estimate for each frequency is obtained by sliding windowed average of the samples over azimuthal angles. The maximal probability amplitudes of the initial ZDC estimates are then calculated for each frequency. Refined ZDC estimates are finally obtained through threshold processing based on the maximal probability amplitude statistics. In this way, the residual target signal components in the initial ZDC estimates are greatly suppressed. As a consequence, accurate background clutter extraction and subtraction are achieved. The experimental results of outdoor data processing for typical targets are presented to demonstrate the effectiveness of the proposed technique.