J4 ›› 2011, Vol. 38 ›› Issue (5): 165-171.doi: 10.3969/j.issn.1001-2400.2011.05.027

• Original Articles • Previous Articles     Next Articles

Doppler centroid estimation without ambiguity in DBS

ZUO Lei;LI Ming;ZHANG Xiaowei   

  1. (National Key Lab. of Radar Signal Processing, Xidian Univ., Xi'an  710071, China)
  • Received:2010-08-22 Online:2011-10-20 Published:2012-01-14
  • Contact: ZUO Lei E-mail:lzuo@mail.xidian.edu.cn

Abstract:

Doppler centroid, a foundational parameter of Doppler Beam Sharpening (DBS), needs to be estimated from echoes. Traditional estimated methods have a shortcoming of the ambiguity to pulse repetition frequency (PRF). The inaccuracy of Doppler centroid resulting from inertial navigation units measurement errors when resolving the ambiguity declines the quality of an image. A novel method has been proposed in this paper to estimate the Doppler centroid without ambiguity. According to the constant speed rotation of the antenna, from the expression for the coherent echoes, two parameters can be estimated, i.e., initial azimuth angle of the first echo in the coherent echoes, and the product of the velocity of plane and the cosine of elevation angle. Then Doppler centroid of the coherent echoes will be calculated from them without ambiguity. The results of computer simulation and the processing results of real DBS data prove the effectiveness of the processing procedure.

Key words: Doppler beam sharpening, Doppler centroid, mechanical scanning, parameter estimation