Frequency-agile slot antenna using capacitive loaded parallel strips

In this paper, a novel frequency-agile slot antenna using capacitive loaded parallel strip islands was proposed. By varying the loaded capacitors´ value, the length of the slot is adjusted equivalently, thus the resonant frequency can be tuned. Measurement results of a prototype slot antenna verify the operating frequency of the antenna can be varied from 1.20 GHz to 1.7 GHz while loading capacitors vary from 1.8 pF to 0.5 pF. As for the radiation patterns, consistent radiation pattern directions are obtained in the entire tunable frequencies which are similar to the typical slot-antenna´s radiation pattern.