Circular Loop Antenna In Unbounded Chiral Medium: A Moment Method Solution

Abstract

This paper addresses the problem of a thin loop antenna of arbitrary radius radiating in an infinitely extending chiral medium. The integral equation for the problem has been formulated and solved using Numerical Electromagnetics Code modified accordingly. It is found that with the additional parameter of chirality one can control the radiation characteristics. It is observed that for a typical case of a loop of radius equal to a half wavelength the radiation resistance increases from about 140 ohms to 310 ohms when the chirality parameter changes from 0.0 (achiral) to 0.003. Also, the patterns become more directive with chirality than in the achiral case for the same electrical size of the loop. The current on the loop decays very quickly with large chirality. Some details of the numerical exercise associated with the moment solution in the chiral NEC code are discussed.