A COMPACT WIDEBAND PATCH ANTENNA LOADED BY INTERDIGITAL CAPACITOR WITH EQUIVALENT CIRCUIT MODEL
Keywords:Compac, wideband, interdigital capacitor, equivalent circuit
In this paper a wideband microstrip patch antenna (MPA) using aperture coupling feeding technique with bandwidth (BW) of 28% is designed at first. Afterwards for the pupose of reducing the size of the radiating element, the composite right/left hand (CRLH) concept is used by implementing an interdigital capacitor (IDC) as series left hand component in the antenna. The slot in the ground plane acts as a left hand parallel inductor. Through this technique, three operation modes of CRLH antenna is excited and by appropriate adjusting of the IDC parameters, closing and mixing of resonant frequencies are achieved. Size reduction in the order of 15.5% and 6.2% in the patch and slot dimensions compared to the initial designed antenna is obtained respectively. The equivalent circuit model of the final designed antenna is presented and simulated. The final designed antenna is fabricated and tested.
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