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Polar format algorithm wavefront curvature error compensation using 2D space-variant post-filtering
Received date: 2014-02-24
Revised date: 2014-09-28
Online published: 2014-10-10
Supported by
National Natural Science Foundation of China (61301210); Natural Science Foundation of Jiangsu Province (BK20130815); Ph. D. Programs Foundation of Ministry of Education of China (20123218120021)
The space-variant defocus effect introduced by wavefront curvature error in polar format algorithm (PFA) imagery limits its maximal focused scene size. Space-variant post-filtering (SVPF) is an efficient approach to compensate for this error. However, to simplify the analysis, all the existing SVPF methods take some approximation on the wavefront curvature error. They can still not meet the required precision when imaging large area with very high resolution. In this paper, we provide a new analytical interpretation of polar format algorithm and develop the accurate wavefront curvature expression in 2D spatial frequency domain. Base on this accurate expression, a 2D SVPF is proposed to accurately correct the wavefront curvature error. Finally, simulation experiment validates the theoretical analysis.
DING Lan , MAO Xinhua , ZHU Daiyin . Polar format algorithm wavefront curvature error compensation using 2D space-variant post-filtering[J]. ACTA AERONAUTICAET ASTRONAUTICA SINICA, 2015 , 36(2) : 605 -613 . DOI: 10.7527/S1000-6893.2014.0272
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