J4 ›› 2011, Vol. 38 ›› Issue (3): 90-98.doi: 10.3969/j.issn.1001-2400.2011.03.015

• Original Articles • Previous Articles     Next Articles

Research on the imaging algorithm for missile-borne SAR with downward movement

ZHOU Song;ZHOU Peng;LI Yachao;XING Mengdao;BAO Zheng   

  1. (National Key Lab. of Radar Signal Processing, Xidian Univ., Xi'an   710071, China)
  • Received:2010-05-18 Online:2011-06-20 Published:2011-07-14
  • Contact: ZHOU Song E-mail:zhousong19841101@sina.cn

Abstract:

During the downward movement for Missile-Borne SAR imaging, variation of Doppler FM rates for echo signal severely affects the focusing effect, which is introduced by high vertical velocity and acceleration. For this reason, by using azimuth nonlinear chirp scaling (NLCS), an imaging algorithm for Missile-Borne SAR is proposed in this paper. After range cell migration correction and range compression, variation of Doppler FM rates for the echo signal can be compensated and image distortion can be corrected by the operation of azimuth nonlinear chirp scaling, thus improving the focus depth and focusing effect. Simulation results are provided to validate the effectiveness of the proposed algorithm.

Key words: missile-borne SAR, nonlinear chirp scaling (NLCS), focus depth