Impedances of long antennas in air and in dissipative media

Abstract

Graphs arc pro vided for t he normali zed impcdance of ce nte r-dri ven cylind rical dipole a nLe nnas when irnm_ersed in a ir or in a dissipaLive medium. The electric half-le ngth ranges from 1 to 100 for dipoles in a ir and from 1 to 19.7 for dipoles in a diss ipaLi ve medium. Three rat ios of r adius of the antenna to waveleng t h have been used. The proper t ies of the medium a re exp ressed in terms of the ratio 01 / f3 in the r a nge from zero to one where f3 a nd 01 are, respectively, t he real a nd imaginary parts of t he complex propagatio n cons tant k.