Zhang Xuepan, Liu Lu, Zhang Xuejing
Qian Xuesen Laboratory of Space Technology, Beijing 100094, China.
School of Electronic Engineering, University of Electronic Science and Technology of China, Chengdu 611731, China.
Sensors (Basel). 2017 Jul 26;17(8):1714. doi: 10.3390/s17081714.
Accurate and efficient moving target imaging is an important challenge for targets recognition in current synthetic aperture radar (SAR) combined with a ground moving target indication (GMTI) system. As the key but unknown parameter, the Doppler rates are estimated conventionally by searching any possible values for moving targets imaging. However, this conventional estimation method suffers from low accuracy or low efficiency due to the searching procedure. Focusing on these, we present a method to efficiently image the moving targets without the Doppler rate by Doppler delayed interferometry, and the imaged localization, which is parameterized pseudo-localization, is used to estimate the Doppler rate. In order to improve the estimation accuracy, an improved method based on the Newton method of approximation is proposed by exploiting the unused amplitude information. Compared with the conventional methods, the proposed improved method capable of high accuracy and low computation complexity simultaneously can meet the accurate and efficient requirements in the practical applications. Comparison simulations and real data processing results demonstrate the effectiveness of the proposed methods.
精确高效的动目标成像是当前合成孔径雷达（SAR）与地面动目标指示（GMTI）系统相结合用于目标识别面临的一项重要挑战。作为关键但未知的参数，传统上通过搜索动目标成像的任何可能值来估计多普勒率。然而，由于搜索过程，这种传统估计方法存在精度低或效率低的问题。针对这些问题，我们提出一种通过多普勒延迟干涉测量法对无多普勒率的动目标进行高效成像的方法，并且利用参数化伪定位的成像定位来估计多普勒率。为了提高估计精度，通过利用未使用的幅度信息，提出一种基于牛顿近似法的改进方法。与传统方法相比，所提出的改进方法能够同时实现高精度和低计算复杂度，可满足实际应用中精确高效的要求。对比仿真和实际数据处理结果证明了所提方法的有效性。
