1.3. Analysis of Paraboloidal-Reflector Systems

Abstract

Publisher Summary This chapter presents an overview of paraboloidal-reflector systems. The rf performance of paraboloidal reflectors may be analyzed using various techniques of diffraction theory. Such techniques generally involve the integration of the dyadic Green's function over the currents induced on the reflector. These induced currents are estimated using geometrical optics. In principle, however, they may also be calculated using moment-method techniques or by applying classical results to appropriate boundary-value problems. Once the currents are determined, evaluation of the fields becomes straightforward although the computations may be lengthy and laborious. Computers are generally needed for all but a few special cases that may be integrated in closed form. The analysis of the transmitting properties of the antenna is presented in the chapter. An analysis and the geometry of the paraboloid with a prime-focus feed are also elaborated and illustrated. The aperture projection of blocked portions of a paraboloidal reflector is displayed and the classical dual-reflector antenna systems are analyzed. The calculation of radiation from dual-reflector systems by applying physical optics (PO) is also discussed.