UWB Monopole Antenna With Two Notched Bands Based on the Folded Stepped Impedance Resonator

In this letter, a novel ultrawideband (UWB) antenna with dual sharply rejected notch bands is proposed. The proposed antenna consists of a circular-shaped radiating element, a 50microstrip feed line, two short-circuited folded stepped impedance resonators (SIRs), and a partially truncated ground plane. The compact folded SIRs are located beside the feed line to achieve the band rejection characteristic. The proposed antenna shows UWB characteristics from around 3.07 up to 10.61 GHz for VSWR<;2 with one notch frequency band at 3.41~3.68 GHz and the other at 5.37~6.01 GHz. The notched frequencies can be adjusted according to speciήcation by altering the folded SIR.