Wideband imaging of concealed objects using compressive radar holography

Radar holography has been established as an effective image reconstruction process by which the measured diffraction pattern across an aperture provides information about a three-dimensional target scene of interest. Compressive sensing has emerged as a new paradigm in applications involving large amounts of data acquisition and storage. The fusion of these two fields of research has had only limited consideration in radar applications. Typically, full sets of data are collected at the Nyquist rate only to be compressed at some later point, where information-bearing data are retained and inconsequential data are discarded. However, under sparse conditions, it is possible to collect data at random sampling intervals less than the Nyquist rate and still gather enough meaningful data for accurate signal reconstruction. In this paper, we employ sparse sampling techniques in the recording of digital microwave holograms over a two-dimensional scanning aperture. Using a simple and fast non-linear interpolation scheme prior to image reconstruction, we show that the reconstituted image quality is well-retained with limited perceptual loss.