Resolution Analyses of Radar Tomographic Imaging for Arbitrary Angle Aperture

The technique of tomography, which collects a set of electromagnetic waves from a target over various angles, is a basic method to form 2-D images of a tridimensional object. However, the resolution ability of the radar tomographic imaging (RTI) has not been fully addressed. Therefore, based on the typical RTI algorithm called inverse Radon transform, this letter deduces its resolution performance in the cases of whole-angle aperture, small-angle aperture, and arbitrary-angle aperture, respectively. It has been proved that the resolution performance of inverse-synthetic-aperture-radar imaging is actually equivalent to that of the RTI at a small-angle aperture. Furthermore, aside from bandwidth, the carrier frequency and the relative position between the target and the radar also play crucial roles on the resolution ability of the RTI.