Tulip-like UWB Antenna with Switchable Bulllike Slot for double/triple Band Rejection

A tulip-like reconfigurable microstrip with a bulllike slot antenna using switchable double and triple band notch functions for UWB application is presented in this study. In the proposed structure, the main antenna with a size of 25×25 mm2 is used and an additional resonance is excited by slitting two symmetric notches on feed-line. As the first step, the Bull-like slot is cut on the radiating patch and a circular slot on the ground plane. Then, three switches are embedded along the bull-like slot, two switches on the circular slot and a parasitic patch with GS3 switch is connected to the ground plane. The switches of ground plane are integrated together with a simple circuit and operate as a unite switch that is called GS. By changing the bias states of theswitches, the antenna can exhibit five different performances of UWB spectrum coverage. In first case when the GS switch is OFF and the other switches on the main patch are ON, that UWB characteristic is obtained. Through the next following cases, the GS switch is set in ON state permanently and by changing the state of main patch switches, in all modes X-band is rejected. Also in second case Bluetooth and C-band, in third case WiMAX, in fourth case Bluetooth and in fifth one Bluetooth and WLAN are rejected.

Keywords:

Reconfigurable antenna , Band rejection structure , Tulip- like , Defected Ground Surface (DGS) , Ultra-Wide Band (UWB)