Design of UWB Monopole Antenna Using Complementary Stubs to Get Dual Notch

Abstract

Ultra-wide Band (UWB) antennas are used to transmit pulses of very short duration. In this paper UWB antenna with dual notch has been proposed. It consists of the circular patch antenna with microstrip feedline along with partial ground plane and two slots on the patch. These two slots also called complementary stubs. They are used to produce dual notch in the UWB range. The smaller slot closed to the circumference of the patch which acts as ƛ/4 complementary stub is used to create notch at 3.5 GHz to reject WLAN band. The semicircular slot which acts as ƛ/2 complementary stub is used to create notch at center frequency 5.5 GHz of WiMax. There is reduction in gain as well as efficiency of the antenna at these rejected frequencies by insertion of two slots there by creating dual notch in the UWB range. Due to dual notch characteristics the interference from ISM band namely WLAN and WiMax to UWB band can be reduced considerably. Such UWB antenna is suitable for wide range of applications.