Wide-beam SAR autofocus based on blind resampling

J Chen, H Yu - Science China Information Sciences, 2023 - Springer
Long synthetic aperture time and large instantaneous beam can turn airborne synthetic
aperture radar (SAR) autofocus into a wide-beam autofocus problem; ie, the motion error is …

Blind NCS-based autofocus for airborne wide-beam SAR imaging

J Chen, J Zhang, H Yu, G Xu, B Liang… - IEEE Transactions …, 2022 - ieeexplore.ieee.org
The improvement in azimuth resolution and/or the increase in the instantaneous beam width
can result in a wide-beam autofocus problem in airborne synthetic aperture radar (SAR) …

A coarse-to-fine autofocus approach for very high-resolution airborne stripmap SAR imagery

J Li, J Chen, P Wang, O Loffeld - IEEE Transactions on …, 2018 - ieeexplore.ieee.org
An autofocus operation is an indispensable procedure to obtain well-focused images for
synthetic-aperture radar (SAR) systems without precise navigation devices. Three …

Knowledge-aided 2-D autofocus for spotlight SAR range migration algorithm imagery

X Mao, X He, D Li - IEEE Transactions on Geoscience and …, 2018 - ieeexplore.ieee.org
With continuous improvement of the synthetic aperture radar (SAR) resolution, the 2-D
defocus effect in SAR image resulting from uncompensated motion error has made …

Time-domain autofocus for ultrahigh resolution SAR based on azimuth scaling transformation

H Lin, J Chen, M Xing, X Chen, N Li… - IEEE Transactions on …, 2022 - ieeexplore.ieee.org
For ultrahigh resolution synthetic aperture radar (SAR), azimuth spectrum aliasing limits the
application of frequency-domain autofocus algorithms. Therefore, time-domain autofocus …

2-D frequency autofocus for squint spotlight SAR imaging with extended omega-K

H Lin, J Chen, M Xing, X Chen, D You… - IEEE Transactions on …, 2021 - ieeexplore.ieee.org
In the existing time-domain autofocus algorithms, the azimuth deramping operation will
change the azimuth-independent phase into the azimuth-dependent phase, which may …

Robust two-dimensional spatial-variant map-drift algorithm for UAV SAR autofocusing

G Wang, M Zhang, Y Huang, L Zhang, F Wang - Remote Sensing, 2019 - mdpi.com
Autofocus has attracted wide attention for unmanned aerial vehicle (UAV) synthetic aperture
radar (SAR) systems, because autofocus process is crucial and difficult when the phase …

Extended autofocus backprojection algorithm for low-frequency SAR imaging

L Chen, D An, X Huang - IEEE Geoscience and Remote …, 2017 - ieeexplore.ieee.org
Since the trajectory deviations of a radar platform cause serious phase errors that degrade
the focusing quality of synthetic aperture radar (SAR) imagery, an autofocus method is very …

A less-memory and high-efficiency autofocus back projection algorithm for SAR imaging

K Hu, X Zhang, S He, H Zhao… - IEEE Geoscience and …, 2014 - ieeexplore.ieee.org
The back projection (BP) algorithm is an accurate time-domain imaging method for synthetic
aperture radar. However, the influences of wind field and turbulence on the platform make …

Extension of map-drift algorithm for highly squinted SAR autofocus

L Ran, Z Liu, T Li, R Xie, L Zhang - IEEE Journal of Selected …, 2017 - ieeexplore.ieee.org
For highly squinted synthetic aperture radar (SAR) imaging, the Omega-k algorithm is
generally accepted as an effective focusing processor. However, the performance of the …