An Efficient Motion Error Compensation Method for Linear Array 3-D SAR Imaging

In order to overcome layover and shadowing effects, three-dimentional(3-D) synthetic aperture radar(SAR) systems have developed rapidly. One of them is linear array SAR(LASAR). Therefore, the image result may defocus due to the antenna phase centers(APCs) motion measurement error. Thus a novel LASAR motion compensation approach is proposed. Based on the analysis that linear array motion error is approximately linear, the method estimates only selected APCs' phase error and derive the whole array's phase error via extrapolation. The compensation scheme is verified with simulations.

1. Introduction

LASAR has attracted significant interest recently. With 3-D imaging capability, it is suitable for surveying complex terrians [1], [2]. Using a linear array attenna to synthesize a large vitual two dimentional aperture, LASAR achieves high along-track resolution and cross-track resolution.