J4 ›› 2015, Vol. 42 ›› Issue (1): 62-68.doi: 10.3969/j.issn.1001-2400.2015.01.010

• Original Articles • Previous Articles     Next Articles

Analysis of the two-dimensional spatial resolution for the curved trajectory of GEO SAR

CHEN Jianlai;LI Zhenyu;YANG Jun;SUN Guangcai;XING Mengdao   

  1. (National Key Lab. of Radar Signal Processing, Xidian Univ., Xi'an  710071, China)
  • Received:2013-10-20 Online:2015-02-20 Published:2015-04-14
  • Contact: CHEN Jianlai E-mail:jianlaichen@163.com

Abstract:

In geosynchronous earth orbit synthetic aperture radar(GEO SAR), because of such factors as the curve track of the satellite, the influence of earth rotation and so on, there is no explicit expression for the moving track of the satellite with respect to the target, and the track velocity varies greatly on different obit positions of the satellite, so the method of calculating resolution for uniform line motion in airborne and LEO SAR is not suitable for GEO SAR. Aiming at the mentioned problems, this paper proposes a method of calculating the two-dimensional spatial resolution based on phase gradient analysis in GEO SAR. In this paper, a conjecture is presented and proved by introducing the intermediate value theorem. There exists an equal track velocity, which can ensure the theoretical azimuth resolution within a range, and that azimuth resolution range is calculated. Finally, the Back projection (BP) algorithm simulation experiments validate the proposed method.

Key words: geosynchronous earth orbit(GEO), phase gradient, two-dimensional spatial resolution, intermediate value theorem, backprojection (BP) algorithm