Wideband impedance measurement of balanced antenna using the S-parameter method

A balanced fed antenna for the portable radio terminal is received increasing attention due to reduction of the human influence. Recently, a technique called S-parameter method using a standard network analyzer has been proposed whereby the differential impedance can be found. In this paper, four compensating methods using cascade matrices are adopted to reduce the influence of a jig for the S-parameter method. The results of our proposed methods are presented and compared with a calculated result using the moment method and the measured result of a monopole antenna on a ground plane.