This paper describes the detection and identification of buried objects, at shallow depths, from the complex-valued reflectance of electromagnetic waves that are radiated and received by an antenna. The antenna is scanned over an area to search for the object. Because object depth is shallow, the antenna is placed in the object's nearfield. The measured distribution of reflectance is processed to form an image which gives shape because diffraction spreading is slight in the nearfield. The reflectance over the object's center is processed by inversion to yield object depth, thickness, and refractive index from multiple frequency measurements; the object is assumed homogeneous as is the contiguous region.

Date Published: 1 November 1990
PDF: 9 pages
Proc. SPIE 1351, Digital Image Synthesis and Inverse Optics, (1 November 1990); doi: 10.1117/12.23627

Published in SPIE Proceedings Vol. 1351:
Digital Image Synthesis and Inverse Optics
Arthur F. Gmitro; Paul S. Idell; Ivan J. LaHaie, Editor(s)