Back-scatter by dielectric spheres (Refractive index approx 1.6

Author

Atlas, D. ; Battan, L. ; Harper, W. ; Herman, B.M. ; Kerker, M. ; Matijevic, E.

Author_Institution

Air Force Cambridge Research Lab., Bedford, MA, USA

Volume

11

Issue

1

fYear

1963

fDate

1/1/1963 12:00:00 AM

Firstpage

68

Lastpage

72

Abstract

Two independent sets of experimental results are presented on the back-scatter from plexiglass spheres. These are compared with theoretical computations for refractive indices m = 1.60, 1.61 and 1.61-0.0025i. For $\\alpha$ (ratio of perimeter to wavelength) $\\leq 7.5$ , the upper limit of the experimental data, the theoretical values are practically identical to one another and agreement with experiment is excellent. For $\\alpha > 7.5$ , the theoretical values diverge from one another. The small absorption coefficient has an increasingly important effect as the spheres grow larger, but even at $\\alpha \\simeq 100$ , the cross section remains above its asymptotic value. Except for the interval $30< \\alpha < 40$ , plexiglass spheres have larger cross sections than metal ones between $6 < \\alpha < 60$ . This is due to the focusing action of the dielectric sphere and the back surface reflection.

Keywords

Electromagnetic (EM) scattering; Ice; Meteorological radar; Spheres; Absorption; Dielectrics; Equations; Ice; Microwave bands; Mie scattering; Radar cross section; Radar scattering; Reflection; Refractive index;

fLanguage

English

Journal_Title

Antennas and Propagation, IEEE Transactions on

Publisher

ieee

ISSN

0018-926X

Type

jour

DOI

10.1109/TAP.1963.1137973

Filename

1137973