Accession Number : AD0690538

Title :   THE TOW - DIMENSIONAL INVERSE SCATTERING PROBLEM.

Descriptive Note : Interim rept.,

Corporate Author : ILLINOIS UNIV URBANA ANTENNA LAB

Personal Author(s) : Imbriale,William A. ; Mittra,Raj

Report Date : MAY 1969

Pagination or Media Count : 92

Abstract : The report demonstrates that the knowledge of the incident field, and the scattered far fields at one frequency, is sufficient to determine the size, shape and location of a perfectly conducting scatterer. The reconstruction of the scattering body is accomplished via an analytic continuation procedure that generates the fields in the neighborhood of the scatterer from the specified far field distribution. The geometry of the body is then determined by locating a closed surface for which the total tangetial electric field is zero. Whereas exact knowledge of the entire far field is sufficient to determine the scatterer, a technique is also given for size and shape determination when only part of the far field is available. Numerical examples of several different geometries are given for ranges of ka('a' the largest dimension of the body) from .2 to 10. Geometries considered were elliptic and circular cylinders, conducting strips and two cylinders. Plots of the fields reconstructed from the far field data are compared to the known solutions and the accuracy of the procedure is demonstrated. The effects of noise in the far field pattern were also considered and it is shown that even with noise levels of -20db, the scattering geometry can be recovered. (Author)

Descriptors :   (*RADIO WAVES, SCATTERING), (*RADAR SIGNALS, SCATTERING), DIFFRACTION, CYLINDRICAL BODIES, NOISE(RADIO), ALGORITHMS, FOURIER ANALYSIS

Subject Categories : Radiofrequency Wave Propagation

Distribution Statement : APPROVED FOR PUBLIC RELEASE