Motion compensation is often a prerequisite to get focused synthetic aperture radar (SAR) images with complicated radar platform flight paths. How to implement accurate motion error compensation is still a great challenge, since the error has inherent space-variant property. In this paper, a three-order motion compensation strategy is proposed. The first order compensation corrects the space-invariant motion error by using scene center as a reference. Then, digital spotlight preprocessing is applied to partially compensate the space-variant error. Finally, the residual space-variant error in subpatch is corrected by the polar format algirhtm (PFA). Simulation results show that the proposed method can provide accurate image formation even under conditions of complicated radar flight paths and rugged imaging terrain.
MAO Xinhua
,
ZHU Daiyin
,
ZHU Zhaoda
. Space-variant Motion Compensation for Airborne Spotlight SAR Under Complicated Flight Path and Rugged Terrain[J]. ACTA AERONAUTICAET ASTRONAUTICA SINICA, 2012
, (4)
: 744
-754
.
DOI: CNKI:11-1929/V.20120201.0940.001
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