Reconstruction of MMW near-field image with antenna-radiation-pattern deconvolution processing

This paper describes the enhancement of special resolution with a new two-dimensional image reconstruction algorithm in millimeter-wave near-field images. The algorithm deconvolutes the images with the near-field radiation pattern from an antenna, which is not based on plane-wave decomposition and provides a constant spatial resolution independent of antenna characteristics. This paper presents reconstruction results from images of a 0.1-mm-wide crack on a concrete block measured at 76.5 GHz. These results demonstrated 2.4-fold enhancement of the spatial resolution by applying our algorithm to the raw image, which is close to the highest resolution determined with the diffraction limit.