Theory and performance of vehicular center-fed whip antenna

The design considerations and results of extensive performance tests of a novel antenna for vehicular communication in the frequency range 30 to 76 mc are given together with applicable theory. The principal features of the antenna include feeding a whip antenna at its center through a coaxial cable, terminating it at its base into a variable reactor with different settings for each one of ten bands, providing separate built-in fixed-tuned matching networks for each band and switching them by means of automatic remote control which is activated by the frequency dial of the radio set. The design of the base reactor comprising a transmission line wound on a ferrite core having a tapped coil connected in parallel with it, and of the transmission line inside the whip are discussed in detail. Measured current distributions, radiation patterns, impedance plots and other performance data are presented.