ABSTRACT
Aiming at limitations of being hard to meet the far-field condition in the microwave darkroom, this article puts forward idea of the construction of confocal tomography imaging. Combining synthetic aperture with focal tomography methods, the paper presents a diagnosis scheme which is confocal tomography imaging in near-field based on circular scanning, the radar antenna on the arc path to complete the space-time onfocal imaging. Unlike the traditional 2D and 3D imaging, the radar platform is moving over the target area, the trace and imaging district center formed a confocal cone shape. Collect the near-field downwardlooking CSAR (Circular Synthetic Aperture Radar) data along the circumferential scan path. Due to the spectral components of the echo in the height direction, it has the capability of extracting 3d information from 3d image. Moreover, different from LSAR, it will not generate phase ambiguity in the height direction.
