A Multi-functional UWB Band-notched Antenna using PIN Diode and Varactor Diode for Wireless Applications

In this paper, a multi-functional band-notched ultra wide band antenna is proposed. At first, band-notching characteristics of monopole antenna with single EBG unit cell is considered as reference antenna. By loading PIN and varactor diodes within the EBG unit cell, multi band-notch functions of proposed antenna are investigated. Using proper combination of PIN diode switching (ON/OFF) and capacitance of varactor (2.35 to 0 pf), antenna is operated as dual, triple and quad bandnotched. Radiation characteristics for proposed UWB antenna are also reported which obeys perfect Bi-directional and Omni- directional patterns in E-plane and H-plane respectively. Using one PIN and varactor diode, the proposed antenna is operated in 12 different band-notching states with tunability in dual, triple and quad bandnotch frequencies. Therefore wireless applications wherein multi-functional band-notched operating states along with reconfiguration using a single antenna structure is desirable, proposed UWB antenna stands out to be very useful.