Scattering of Waves by Conducting and Dielectric Objects

In radar, the radio wave is transmitted toward an object and the scattered wave received by an antenna reveals the characteristics of the object, such as its position and motion. This chapter develops basic formulations of the scattering problem, discusses possible potential applications. When an object is illuminated by a wave, a part of the incident power is scattered out and another part is absorbed by the object. The characteristics of these two phenomena, scattering and absorption, can be expressed by assuming an incident plane wave. The chapter discusses the scattering characteristics of a conducting body, particularly the backscattering cross section for radar applications. It presents an overall view of how these cross sections are related to the geometric cross section, wavelength, and dielectric constant. The chapter describes the physical optics approximation to give a convenient expression for the surface current, and thus it is widely used for many applications.