An ultra-wideband microstrip antenna with double notches

This paper presents an ultra-wideband(UWB) microstrip patch antenna with a simple pentagonal geometry and two notches. The UWB characteristics is achieved by using defective ground and impedance conversion methods, yielding a frequency band coverage from 3.1 GHz to 10.6 GHz where the voltage standing wave ratio(VSWR) is no more than 2. A rectangular slit and a narrow U-shape slot are etched in on the patch and feed-line respectively to achieve notch performance at WLAN band(5.15 GHz~5.85 GHz) and X-band communication downlink band(7.25 GHz~7.7 GHz). The antenna presents good radiation characteristics in its operational UWB, and measured results are in good agreements with the simulation, which accordingly validates the design.