Double MOS Loaded Circular Microstrip Antenna with Airgap for Mobile Communication

A novel model of a wide frequency range double MOS loaded circular microstrip patch antenna with airgap between ground plane and substrate is proposed. In this structure two metal oxide semiconductor (MOS) devices are loaded on the patch to enhance the operating frequency range of antenna. To investigate the antenna, different parameters such as resonance frequency, input impedance, frequency agility, VSWR, radiation pattern etc. are calculated and simulated. The resonant frequency of proposed 10mm radius patch is upward shifted from 5.2 to 6.8GHz using 1mm airgap and by loading MOS, antenna can be tuned down to 1.27GHz operating frequency, which leads to compactness and tunability of antenna. Proposed antenna can be tuned between 1.27 and 6.8GHz frequency of operation whichmakes the antenna highly suitable for wide frequency range of mobile communication. The proposed doubleMOS loaded antenna possessed 82.94% frequency agility. The antenna is worth for GPS, WLAN, UMTS, and WiMAX operations.