J4 ›› 2010, Vol. 37 ›› Issue (6): 1033-1041+1064.doi: 10.3969/j.issn.1001-2400.2010.06.010

• Original Articles • Previous Articles     Next Articles

Analysis of the characteristics of geosynchronous SAR in the elliptic orbit and a study of imaging methods

BAO Min1;LI Ya-chao1,2;XING Meng-dao1;WANG Wan-lin2;LI Cai-pin2
  

  1. (1. National Lab. of Radar Signal Processing, Xidian Univ., Xi'an  710071, China;
    2. National Key Lab. of Sci. and Tech. on Space Micro. Tech., Xi'an  710000, China)
  • Received:2010-04-27 Online:2010-12-20 Published:2011-01-22
  • Contact: BAO Min E-mail:mbao627@china.com.cn

Abstract:

The elliptic orbit module and property of motion of geosynchronous synthetic aperture radar (GEOSAR) are analyzed. The paper discusses in detail the Doppler property of the GEOSAR target in the elliptical orbit. Satellite attitude changes have significant effects on GEOSAR imaging. By deducing the Doppler parameters expression with the satellite attitude variety, it is discovered that we should enhance the measurement precision of the pitch angle and roll angle. The nonlinear motion of the satellite orbit should be taken into account in GEOSAR imaging, so that the SPECAN algorithm, RD algorithm and back-projection algorithm are compared and analyzed, and it is proved that the three imaging approaches are feasible in GEOSAR imaging. Computer simulation results validate the  conclusions obtained through analysis and the imaging method.

Key words: synthetic aperture radar, geosynchronous orbits, Doppler parameter, satellite attitude, back-projection