Frequency Tuning Characteristics & Bandwidth Enhancement for Circular Microstrip Antenna by Integrating L Shaped DGS

In the ground surface a symmetrical defective ground structure (i.e. DGS) in L form was implemented for which circular microstrip antenna was resonant at second WLAN band , i.e. 5.8GHz. The geometry of the DGS was optimized to achieve lower application frequency bands viz. GSM band, Bluetooth band ,WiMax band and first WLAN respectively. As a result, the frequency tunability for the proposed antenna is observed in the application frequency bands with optimum bandwidth and gain. In order to achieve improved bandwidth at GSM and WiMax bands, dual L-shaped DGS is integrated into the ground plane of the proposed antenna.