A New Nonlinear Chirp Scaling Algorithm for High-Squint High-Resolution SAR Imaging

Among high-squint high-resolution (HSHR) synthetic aperture radar imaging algorithms, nonlinear chirp scaling algorithm (NLCSA) and its extensions, such as extended NLCSA (ENLCSA), have a common drawback in that they all neglect the spatial variations of linear range migration (LRM) and Doppler cent...

Full description

Saved in:
Bibliographic Details
Published in:IEEE geoscience and remote sensing letters Vol. 14; no. 12; pp. 2225 - 2229
Main Authors: Wang, Yan, Li, Jingwen, Xu, Feng, Yang, Jian
Format: Journal Article
Language:English
Published: Piscataway IEEE 01.12.2017
The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
Subjects:
Algorithms
Azimuth
Chirp
Coefficients
Computer simulation
Doppler effect
Doppler sonar
Ground plane
High resolution
High-squint high-resolution (HSHR)
Image resolution
Imaging
Imaging techniques
Interpolation
Mathematical models
Neglect syndromes
new nonlinear chirp scaling algorithm (NLCSA)
Perturbation methods
Radar
Radar imaging
Radar polarimetry
Resolution
SAR (radar)
Scaling
Spatial variations
Synthetic aperture radar
synthetic aperture radar (SAR) imaging
ISSN:1545-598X, 1558-0571
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Among high-squint high-resolution (HSHR) synthetic aperture radar imaging algorithms, nonlinear chirp scaling algorithm (NLCSA) and its extensions, such as extended NLCSA (ENLCSA), have a common drawback in that they all neglect the spatial variations of linear range migration (LRM) and Doppler centroid, and thus, only targets in a specific central slant range plane can be strictly focused. In this letter, we show that by using a new NLCSA, targets can be focused in the ground plane under HSHR conditions. Based on a more accurate 2-D spectrum, the new NLCSA outperforms the ENLCSA by introducing a new range-Doppler domain interpolation to correct residual range migration and a new perturbation function to remove the dependence of Doppler phase on azimuth. The coefficients of the new perturbation function are numerically calculated and then smoothed by polynomial fitting. Though the outputs of the numerical calculation are somewhat unstable at the current stage, it has been demonstrated to perform better than the algorithms neglecting the spatial variations of LRM and Doppler centroid, such as the ENLCSA, by point target simulations.
Bibliography:ObjectType-Article-1
SourceType-Scholarly Journals-1
ObjectType-Feature-2
content type line 14
ISSN:1545-598X
1558-0571
DOI:10.1109/LGRS.2017.2758386