Comparison between a novel liquid switch and a GaAs MMIC switch for reconfiguring the operating frequency of a Vivaldi antenna

This article proposes a novel liquid switch to reconfigure the operating frequency of a frequency-independent antenna. A Vivaldi antenna using a low-cost GaAs MMIC RF switch is used as a landmark to compare the measured results. Two prototypes are measured in an anechoic chamber and the results have been compared. The antennas operate in two modes: low-band mode at 3 GHz with 11 dBi of gain and high-band mode operating at 4.5 GHz with a measured gain of 10.8 dBi. The reconfigurable Vivaldi antenna proposed here presents high isolation between operating bands, a minimum of 12 dB, while maintaining high gain and stable radiation pattern which is suitable for cognitive radio applications.