The research of near-field INISAR imaging diagnosis

The study of electromagnetic scatter characteristic is significative for reducing the RCS(radar cross section) of radar target and improving the stealth performance of weapon system. For diagnosing the scattering coefficients distribution of radar target exactly, the mechanism of microwave imaging is analyzed in this paper, a novel near-distance high-resolution microwave imaging approach is presented. Rectify the curved wave front according to the structure characteristic of aircraft, the modified spherically back-projecting method is used to reconstruct 2-D image in near-field, then the 3-D INISAR image is derived from two ISAR images at different altitudes by using interferometric image processing. The effectiveness of the approach is demonstrated by the imaging experiment of aircraft scale model in microwave anechoic chamber, and it shows that the novel approach has potential signification in engineering.