An Experimental Study of an Electrically Thick, Tubular, Monopole Antenna Driven by a Coaxial Transmission Line

Current distribution and input admittance of an electrically thick, tubular, monopole antenna driven by a coaxial transmission over a ground plane has been investigated and compared with theoretical results. When the circumference of the antenna is comparable to a free-space wavelength, this experiment verifies that the theoretical model of a tubular dipole antenna with a delta-function excitation only on the outside surface describes the experimental situation more properly than the conventional model of a deltafunction excitation on both outside and inside surfaces of the antenna. j n-mitv ■■''■ i,ii<'iii.r.t-' ■■ I ftmaautUBUaUa^tiVtSitMIIUaiillliaiiaimm ,-.r^-w-.t .■ ..j.J,,..^»^.j^i.^.^..^J.<.,^.._.J.,^j.i^:^-u-^.-....J.i4a^^M^Ji.ii.,miM» iiwygjjjw^^ ——^ mmrvwimw.A. iumumw WIIM.IM. ilUppi . mW-WiiMi'l. "■■' ,N>.'Mt„WM'<nw'-'i'"^Hi.!'