ACTA AERONAUTICAET ASTRONAUTICA SINICA >
A Novel Frequency Domain Back-projection Algorithm for Ultra-high Resolution SAR Imaging
Received date: 2013-04-27
Revised date: 2013-11-26
Online published: 2013-12-25
Supported by
NUAA Fundamental Research Funds (NS2013023); National Natural Science Foundation of China (61201325, 61301212);Defense Industrial Technology Development Program(B2520110008)
In an ultra-high resolution airborne synthetic aperture radar (SAR), both the bandwidth of the transmitted signal and the synthetic aperture time are increased, which results in higher requirements for accuracy and efficiency of the imaging algorithms. Many problems exist when using the approximated frequency domain algorithms and time domain filtered backprojection (FBP) algorithm to process SAR data. Based on microlocal analysis, this paper proposes a novel frequency domain FBP (FD-FBP) algorithm. In this algorithm, Keystone transform is used to simplify the range cell migration expression of the SAR data in range Doppler(RD) domain first. Then, backprojection operation is implemented in RD domain, where shift, phase compensation and FFT operations are performed on the backprojected data of reference imaging points to obtain the imagery, which reduces the computational burden and realizes the combination of the efficiency of frequency domain algorithms and accuracy of the time domain algorithms. Finally, point target simulation and real-data processing result and their comparison with the FBP algorithm results validate this algorithm.
WANG Xin , WANG Ling , ZHU Daiyin . A Novel Frequency Domain Back-projection Algorithm for Ultra-high Resolution SAR Imaging[J]. ACTA AERONAUTICAET ASTRONAUTICA SINICA, 2014 , 35(4) : 1053 -1063 . DOI: 10.7527/S1000-6893.2013.0475
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