J4 ›› 2011, Vol. 38 ›› Issue (5): 108-114.doi: 10.3969/j.issn.1001-2400.2011.05.018

• Original Articles • Previous Articles     Next Articles

SAR interference suppression algorithm for narrow band interference via wavelets

ZHANG Shuangxi;ZHANG Lei;GUO Rui;ZHOU Peng;XING Mengdao   

  1. (National Key Lab. of Radar Signal Processing, Xidian Univ., Xi'an  710071, China)
  • Received:2010-10-29 Online:2011-10-20 Published:2012-01-14
  • Contact: ZHANG Shuangxi E-mail:shuangxizhang1984@163.com

Abstract:

The presentation of Narrow-band interference (NBI) usually degrades the imaging quality dramatically. Based on the time-frequency feature analysis of NBI, a new NBI suppression algorithm is proposed by Wavelets transform in this paper. In this algorithm, spectrum of echo corrupted by NBI is transformed into multi-resolution wavelet domain. Then the NBI components can be identified and subsequently filtered out while preserving useful signal as much as possible by constant-false-alarm-rate. In the following, the data after NBI suppression is transformed into the original echo domain. Finally, well-focused SAR imagery can be obtained from the echoes without NBI by traditional SAR imaging algorithm. The loss of the effective data during the operation is smaller than other NBI suppression algorithm. In addition, this algorithm is robust to time-varying NBI. Imaging results of both simulation data and measured data have proved the validity of this algorithm.

Key words: synthetic aperture radar (SAR), narrow-band interference (NBI), interference suppression, wavelet transform