GMTI for Squint Looking XTI-SAR with Rotatable Forward-Looking Array

Kai Jing; Jia Xu; Zuzhen Huang; Di Yao; Teng Long

doi:10.3390/s16060873

GMTI for Squint Looking XTI-SAR with Rotatable Forward-Looking Array

Sensors (Basel). 2016 Jun 14;16(6):873. doi: 10.3390/s16060873.

Authors

Kai Jing¹, Jia Xu², Zuzhen Huang³, Di Yao⁴, Teng Long⁵

Affiliations

¹ School of Information and Electronics, Beijing Institute of Technology, Beijing 100081, China. jakey@bit.edu.cn.
² School of Information and Electronics, Beijing Institute of Technology, Beijing 100081, China. xujia@bit.edu.cn.
³ School of Information and Electronics, Beijing Institute of Technology, Beijing 100081, China. hzzhit@126.com.
⁴ School of Information and Electronics, Beijing Institute of Technology, Beijing 100081, China. ddyao@bit.edu.cn.
⁵ School of Information and Electronics, Beijing Institute of Technology, Beijing 100081, China. longteng@bit.edu.cn.

Abstract

To realize ground moving target indication (GMTI) for a forward-looking array, we propose a novel synthetic aperture radar (SAR) system, called rotatable cross-track interferometry SAR (Ro-XTI-SAR), for squint-looking application in this paper. By changing the angle of the cross-track baseline, the interferometry phase component of squint-looking Ro-XTI-SAR caused by the terrain height can be approximately adjusted to zero, and then the interferometry phase of Ro-XTI-SAR is only sensitive to targets' motion and can be equivalent to the along track interferometry SAR (ATI-SAR). Furthermore, the conventional displaced phase center array (DPCA) method and constant false alarm (CFAR) processing can be used to accomplish the successive clutter suppression, moving targets detection and relocation. Furthermore, the clutter suppressing performance is discussed with respect to different system parameters. Finally, some results of numerical experiments are provided to demonstrate the effectiveness of the proposed system.

Keywords: along-track interferometry (ATI); cross-track interferometry (XTI); displaced phase center array (DPCA); ground moving target indication (GMTI); parameter estimation; squint looking; synthetic aperture radar (SAR).