Tandem Bistatic Squint SAR Imaging Algorithm Based on the Chirp-Z Transform
Wu Yong-jun①②,Wu Xian-liang①
①Key Lab of Intelligent Computing and Signal Processing, Anhui University, Hefei 230039, China; ②Electronic and Engineering Institute of PLA, Hefei 230037, China
Abstract：This paper firstly setups the geometric model of the tandem bistatic squint SAR and presents the mathematic expression of the radar echoes, then its two-dimensional frequency spectrum is derived and its characteristic is analyzed. In two-dimensional frequency domain, the point targets in the center of the observed scene is precisely imaged by using the focusing function, then the Chirp-Z transform is used to correct the range cell migration of the target echoes in both side of the center points. Finally, the radar images are obtained by the inverse Fourier transform on the azimuth direction. Since the algorithm uses the property of the Chirp-Z transform processing the nonlinear modulation frequency signal, the processing procedure is simplified and the imaging precision is greatly improved. The simulation tests validate this new algorithm based on the Chirp-Z transform to process the data of the tandem bistatic squint SAR.
2010, Vol. 32 
