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Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: Application of Fractional Fourier Transform to Moving Target Indication via Along-Track Interferometry | EURASIP Journal on Applied Signal Processing 2005 20 3293-3303 2005 Hindawi Publishing Corporation Application of Fractional Fourier Transform to Moving Target Indication via Along-Track Interferometry Shen Chiu Radar System Section Defence R D Canada DRDC 3701 Carling Avenue Ottawa ON Canada K1A 0Z4 Em ail shen.chiu@drdc-rddc.gc.ca Received 21 June 2004 Revised 4 March 2005 A relatively unknown yet powerful technique the so-called fractional Fourier transform FrFT is applied to SAR along-track interferometry SAR-ATI in order to estimate moving target parameters. By mapping a target s signal onto a fractional Fourier axis the FrFT permits a constant-velocity target to be focused in the fractional Fourier domain thereby affording orders of magnitude improvement in SCR. Moving target velocity and position parameters are derived and expressed in terms of an optimum fractional angle a and a measured fractional Fourier position Up allowing a target to be accurately repositioned and its velocity components computed without actually forming an SAR image. The new estimation algorithm is compared with the matched filter bank approach showing some of the advantages of the FrFT method. The proposed technique is applied to the data acquired by the two-aperture CV580 airborne radar system configured in its along-track mode. Results show that the method is effective in estimating target velocity and position parameters. Keywords and phrases fractional Fourier transform along-track interferometry parameter estimation. 1. INTRODUCTION Canada s RADARSAT-2 commercial SAR satellite to be launched in spring 2006 will have an experimental mode called MODEX for moving object detection experiment that will allow the full antenna to be broken into two subapertures with two parallel receivers to define two independent data channels 1 . These two subapertures arranged to lie along the flight path record two echoes the dual-receive mode one from each wing for every pulse transmitted at the .
