Accession Number : AD0633099

Title :   FUNDAMENTAL SCATTERING PARAMETERS OBTAINED FROM LOW-N DATA.

Descriptive Note : Technical memo.,

Corporate Author : ELECTRONIC DEFENSE LABS SYLVANIA ELECTRONIC SYSTEMS-WEST MOUNTAIN VIEW CALIF

Personal Author(s) : Hawley,Sandra W. ; Twersky,Victor ; Kays,Thomas H.

Report Date : 01 NOV 1965

Pagination or Media Count : 80

Abstract : Scattering measurements on random distributions are often undertaken to obtain information on the properties of the component scatterers. One seeks to isolate the scattering amplitude (the angle dependent part of the usual far-field form) of a component scatterer, particularly its forward scattered value f = Ref + i Im f. Conventional techniques provide data on the average total intensity and on the coherent phase. Under the best of conditions, coherent intensity and phase data for sparse distributions of concentration rho enable one to determine rho Re f and rho Im f. To isolate f by intensity and phase measurements, one must therefore have some supplementary means of determining rho. Alternatively, other average scattering functions of the distribution can be sought which involve Re f, Im f, and rho differently. In particular, as shown previously, the magnitude of the covariance of the phase-quadrature components of the field depends essentially on rho absolute value of f squared. The theory for isolating f independently of rho is summarized, and several procedures are illustrated by millimeter wave data obtained for different random distributions of spheres. (Author)

Descriptors :   (*MILLIMETER WAVES, SCATTERING), ELECTROMAGNETIC RADIATION, REFLECTORS, SPHERES, STYRENE PLASTICS, EXPANDED PLASTICS, PROBABILITY, DISTRIBUTION, REFRACTIVE INDEX

Subject Categories : Radiofrequency Wave Propagation

Distribution Statement : APPROVED FOR PUBLIC RELEASE