TY - JOUR
T1 - Focus improvement of high-squint SAR based on azimuth dependence of quadratic range cell migration correction
AU - Zhang, Shuang Xi
AU - Xing, Meng Dao
AU - Xia, Xiang Gen
AU - Zhang, Lei
AU - Guo, Rui
AU - Bao, Zheng
PY - 2013
Y1 - 2013
N2 - In this letter, we discuss the problem that linear range cell walk correction in the azimuth time domain may cause space variation along the azimuth not only to the quadratic phase but also to the quadratic range cell migration (QRCM) under the conditions of high resolution and large scene along the azimuth. Moreover, an algorithm is proposed to deal with this problem. The proposed algorithm adopts the azimuth space variation filtering in the range frequency domain. In addition, the range-dependence component of QRCM is corrected by linear chirp scaling, and the unified QRCM can be corrected in the 2-D frequency domain. The proposed algorithm, without interpolation, can be easily implemented by integrating with motion compensation for image processing. Simulation and airborne strip-map real data show the accuracy and efficiency of the proposed algorithm.
AB - In this letter, we discuss the problem that linear range cell walk correction in the azimuth time domain may cause space variation along the azimuth not only to the quadratic phase but also to the quadratic range cell migration (QRCM) under the conditions of high resolution and large scene along the azimuth. Moreover, an algorithm is proposed to deal with this problem. The proposed algorithm adopts the azimuth space variation filtering in the range frequency domain. In addition, the range-dependence component of QRCM is corrected by linear chirp scaling, and the unified QRCM can be corrected in the 2-D frequency domain. The proposed algorithm, without interpolation, can be easily implemented by integrating with motion compensation for image processing. Simulation and airborne strip-map real data show the accuracy and efficiency of the proposed algorithm.
KW - High-squint mode
KW - Linear chirp scaling (LCS)
KW - Nonlinear chirp scaling (NCS)
KW - QRCM correction (QRCMC)
KW - Quadratic range cell migration (QRCM)
KW - Range cell migration correction (RCMC)
KW - Synthetic aperture radar (SAR)
UR - http://www.scopus.com/inward/record.url?scp=84887146688&partnerID=8YFLogxK
U2 - 10.1109/LGRS.2012.2195634
DO - 10.1109/LGRS.2012.2195634
M3 - Article
AN - SCOPUS:84887146688
SN - 1545-598X
VL - 10
SP - 150
EP - 154
JO - IEEE Geoscience and Remote Sensing Letters
JF - IEEE Geoscience and Remote Sensing Letters
IS - 1
ER -