Extended PGA for Spotlight SAR-Filtered Backprojection Imagery
(2022) In IEEE Geoscience and Remote Sensing Letters 19.- Abstract
The phase gradient autofocus (PGA) is a robust autofocusing approach that can efficiently refocus defocused synthetic aperture radar (SAR) imagery produced by frequency-domain algorithms. However, from a conventional viewpoint, PGA cannot be extended to refocus SAR imagery produced by time-domain algorithms, such as the filtered backprojection (FBP), as the spectrum of the FBP imagery is range ambiguous and azimuth space-variant. In this letter, a novel interpretation of FBP is presented, in which the spectrum structure of the FBP imagery is analyzed in detail. By incorporating the derived spectral information, an efficient spectrum preprocessing is proposed for spectrum restructuring. After this preprocessing, PGA is shown to be able... (More)
The phase gradient autofocus (PGA) is a robust autofocusing approach that can efficiently refocus defocused synthetic aperture radar (SAR) imagery produced by frequency-domain algorithms. However, from a conventional viewpoint, PGA cannot be extended to refocus SAR imagery produced by time-domain algorithms, such as the filtered backprojection (FBP), as the spectrum of the FBP imagery is range ambiguous and azimuth space-variant. In this letter, a novel interpretation of FBP is presented, in which the spectrum structure of the FBP imagery is analyzed in detail. By incorporating the derived spectral information, an efficient spectrum preprocessing is proposed for spectrum restructuring. After this preprocessing, PGA is shown to be able to refocus defocused FBP imagery. The validity and feasibility of the proposed autofocusing approach are demonstrated using both simulated and experimental data.
(Less)
- author
- Shi, Tianyue ; Mao, Xinhua ; Jakobsson, Andreas LU and Liu, Yanqi
- organization
- publishing date
- 2022
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- Autofocusing, filtered backprojection (FBP), phase gradient autofocus (PGA), synthetic aperture radar (SAR)
- in
- IEEE Geoscience and Remote Sensing Letters
- volume
- 19
- article number
- 4516005
- publisher
- IEEE - Institute of Electrical and Electronics Engineers Inc.
- external identifiers
-
- scopus:85142813530
- ISSN
- 1545-598X
- DOI
- 10.1109/LGRS.2022.3223164
- language
- English
- LU publication?
- yes
- id
- 99fa2cae-01d0-4d06-9c9f-320cb7022932
- date added to LUP
- 2023-01-31 13:56:30
- date last changed
- 2023-11-18 09:35:18
@article{99fa2cae-01d0-4d06-9c9f-320cb7022932, abstract = {{<p>The phase gradient autofocus (PGA) is a robust autofocusing approach that can efficiently refocus defocused synthetic aperture radar (SAR) imagery produced by frequency-domain algorithms. However, from a conventional viewpoint, PGA cannot be extended to refocus SAR imagery produced by time-domain algorithms, such as the filtered backprojection (FBP), as the spectrum of the FBP imagery is range ambiguous and azimuth space-variant. In this letter, a novel interpretation of FBP is presented, in which the spectrum structure of the FBP imagery is analyzed in detail. By incorporating the derived spectral information, an efficient spectrum preprocessing is proposed for spectrum restructuring. After this preprocessing, PGA is shown to be able to refocus defocused FBP imagery. The validity and feasibility of the proposed autofocusing approach are demonstrated using both simulated and experimental data.</p>}}, author = {{Shi, Tianyue and Mao, Xinhua and Jakobsson, Andreas and Liu, Yanqi}}, issn = {{1545-598X}}, keywords = {{Autofocusing; filtered backprojection (FBP); phase gradient autofocus (PGA); synthetic aperture radar (SAR)}}, language = {{eng}}, publisher = {{IEEE - Institute of Electrical and Electronics Engineers Inc.}}, series = {{IEEE Geoscience and Remote Sensing Letters}}, title = {{Extended PGA for Spotlight SAR-Filtered Backprojection Imagery}}, url = {{http://dx.doi.org/10.1109/LGRS.2022.3223164}}, doi = {{10.1109/LGRS.2022.3223164}}, volume = {{19}}, year = {{2022}}, }