J4 ›› 2012, Vol. 39 ›› Issue (6): 42-48.doi: 10.3969/j.issn.1001-2400.2012.06.007

• Original Articles • Previous Articles     Next Articles

High accuracy estimation of low elevation angle based on the interferometric array in the VHF radar

CHEN Genhua;CHEN Baixiao;ZHU Wei   

  1. (National Key Lab. of Radar Signal Processing, Xidian Univ., Xi'an  710071, China)
  • Received:2012-03-14 Online:2012-12-20 Published:2013-01-17
  • Contact: CHEN Genhua E-mail:cghnd@126.com

Abstract:

Due to the difficulty with the measurement of the low elevation angle on targets near the horizon for VHF radar, combining the interferometry and the advantages of superresolution algorithms, a novel method to estimate low elevation angles with high accuracy based on the interferometric array is proposed. The interferometric array extends the array aperture with small pieces of hardware. The interferometric forward/backward spatial smoothing technique is proposed from the conventional spatial smoothing algorithm for the uniform linear array and is used to decorrelate the ground multipath signal. Then we obtain highly accurate estimation of the low elevation using the dual-size unitary ESPRIT algorithm. Simulation results and real data demonstrate the efficacy of the interferometric forward/backward spatial smoothing technique and the proposed method, with the reasons why there exist the SNR threshold and baseline ambiguity threshold in the proposed method analyzed.

Key words: interferometric array, low elevation angle, spatial smoothing, ambiguity resolution

CLC Number: 

  • TN958