Single Band-Notched UWB Square Monopole Antenna with Double U-slot and Key Shaped Slot

A compact printed monopole ultra-wideband (UWB) antenna with single band-notched characteristics of size 18mm× 12mm on FR4 substrate is proposed. The proposed antenna consists of a pair of slits and two U slots with a key shaped slot combined with one of the U slot. This provides a wide band width from 4.4 to 11.7 GHz with single band frequency notch from 5.2 to 5.8 GHz to avoid interference of UWB band with the existing systems. In this paper variation of frequency notched characteristics are discussed by combining the key shaped slot with U slots. The design parameters and the performance of the proposed antenna are analyzed by using HFSS. The antenna displays a good omnidirectional radiation pattern since it has square radiating patch. The measured and simulated results are in good agreement.