Compact ultra-wideband antenna with band-notched based on defected ground structure

Abstract

A simple and very compact planar monopole ultra-wideband antenna with a 3.5 GHz band rejection is proposed in this Letter. The compact antenna is etched on an FR4 substrate with the size of 14 × 16 × 1 mm^3, consists of a tree-shaped radiation patch with modified ground structure. To reject certain frequency band, a pair of parallel strip patch, acting as a parasitic element is used. Prototype of the proposed antenna was constructed and measured. The measured impedance bandwidth of the realised antenna with optimal parameters is from 2.6 to 12 GHz (128%) for voltage standing wave ratio <2 with an unwanted band notched from 3.3 to 4 GHz. Moreover, the antenna has good omnidirectional radiation patterns in the H-plane.

Keywords

• antenna radiation patterns
• monopole antennas
• ultra wideband antennas
• omnidirectional antennas
• compact ultrawideband antenna
• band notched
• defected ground structure
• planar monopole ultrawideband antenna
• tree shaped radiation patch
• modified ground structure
• parallel strip patch
• parasitic element
• optimal parameters
• omnidirectional radiation patterns
• H-plane
• frequency 3.5 GHz
• frequency 2.6 GHz to 12 GHz
• frequency 3.3 GHz to 4 GHz