3-D back-projection imaging in circular SAR with impulse signal

Circular Synthetic Aperture Radar (CSAR) travels along a circular track and can obtain a 3-D image for the observed space. Conventional 2-D Back-projection imaging algorithm is transformed to 3-D Back-Projection (BP) algorithm for Circular SAR here, which adopts impulse signals. This algorithm is compared with the confocal imaging algorithm, and they are essentially the same which has been proved in this paper. So the analysis with ¿generalized ambiguity function¿, which is used by the confocal algorithm, is introduced here to analyze the vertical resolution of 3-D BP algorithm. Some simulations demonstrate the validity of the algorithm and the resolution analysis result. Finally, an outside experiment shows the practical 3-D imaging result.