Title :
Comments on "Non-iterative quality phase-gradient autofocus (QPGA) algorithm for spotlight SAR imagery"
Author :
Chan, H.L. ; Yeo, T.S.
Author_Institution :
Dept. of Electr. & Comput. Eng., Nat. Univ. of Singapore, Singapore
Abstract :
For original paper see ibid., vol.36, no.5, pt.1, p.1531-9 (1998). The quality phase-gradient autofocus (QPGA) technique was proposed to speed up the estimation convergence of phase-gradient autofocus by selectively increasing the pool of quality synchronization sources instead of selecting the "brightest" pixels within the image. It is now found that the QPGA, with its inherent scatter "growing" concept and target-filtering procedure, is also able to focus in environments with stationary and moving targets.
Keywords :
geophysical signal processing; geophysical techniques; radar imaging; remote sensing by radar; synthetic aperture radar; QPGA technique; estimation convergence; inherent scatter growing concept; moving targets; moving vehicle; noniterative quality phase-gradient autofocus algorithm; spotlight SAR imagery; stationary targets; synchronization sources; synthetic aperture radar; target-filtering procedure; Convergence; Electronics packaging; Focusing; Layout; Phase estimation; Pixel; Radar scattering; Radar signal processing; Signal processing algorithms; Synthetic aperture radar;
Journal_Title :
Geoscience and Remote Sensing, IEEE Transactions on
DOI :
10.1109/TGRS.2002.803720
