Through-the-wall imaging of 3D objects

We propose a unique microwave through-the-wall imaging technology for three-dimensional objects. The imaging technique is based on the Field Mapping Algorithm (FMA), which is a single-frequency direct inversion method requiring neither optimization nor iterative procedures. The imaging system is a reflective detection device consisting of a transmit antenna and a receive probe, both facing the wall under measurement in the same direction. This single-slice, single-frequency near-field data bank suffices as input to our FMA for the subsequent generation of multi-slice 3D field images of the targets behind the wall. The verification of our imaging technique was carried out by field measurements. Five measurement cases at three different frequencies are reported herein by way of demonstration. Good imaging results were obtained in all five measurement cases.