Radar echo variations of a large rough sphere

Author

Burrows, Michael L.

Author_Institution

Massachusetts Institute of Technology, Lexington, Massachusetts, USA

Volume

14

Issue

4

fYear

1966

fDate

7/1/1966 12:00:00 AM

Firstpage

455

Lastpage

460

Abstract

The effect of surface roughness on the radar backscattering cross section of a perfectly conducting nominally spherical target is examined by applying the Kirchhoff method. It is shown that, for the type of roughness and sphere size to which the Kirchhoff method is applicable, the standard deviation of the cross section increases with frequency according to the law $2\\sqrt {2} \\sigma _{0} k\\zeta$ until the first Fresnel zone reduces in size to the scale length of the roughness. At this point a knee in the curve occurs and its further course is determined by a more detailed statistical description of the surface. Here $\\sigma _{0}$ is the nominal cross section, $\\zeta$ is the standard deviation of the surface height $h$ and $k=2\\pi/\\lambda$ , where $\\lambda$ is the wavelength. The average cross section is shown to be given by $\\sigma _{0}[1+0 {(kh)^{3}}]$ . Some experimental results are reported which support the theoretical conclusions.

Keywords

Electromagnetic scattering by absorbing media; Radar scattering cross sections; Spheres; Frequency; Fresnel reflection; Knee; Optical scattering; Optical sensors; Optical surface waves; Radar cross section; Rough surfaces; Surface roughness; Surface waves;

fLanguage

English

Journal_Title

Antennas and Propagation, IEEE Transactions on

Publisher

ieee

ISSN

0018-926X

Type

jour

DOI

10.1109/TAP.1966.1138708

Filename

1138708