Abstract :
A simple and compact ultra-wideband microstrip-fed planar antenna with dual bandstop characteristic is presented. By using a U-slot defected ground structure (DGS) in the feedline, a stopband of 600 MHz (from 5.45 to 6.05 GHz) for band rejection of WLAN is achieved. To obtain another stopband, an arched slot is etched on the radiating patch. Experimental results show that the designed antenna, with a compact size of 30 times 24.5 mm, has an impedance bandwidth of 2.8-11 GHz for voltage standing wave ratio (VSWR) less than 2, except two frequency stop-bands of 3.5-4.25 GHz and 5.45- 6.05 GHz. Moreover, the antenna has good omnidirectional radiation patterns in the H-plane.
Keywords :
UHF antennas; antenna feeds; antenna radiation patterns; band-stop filters; microstrip antennas; microwave antennas; planar antennas; slot antennas; ultra wideband antennas; wireless LAN; H-plane; U-slot defected ground structure; WLAN; dual bandstop characteristic; frequency 2.8 GHz to 11 GHz; frequency 3.5 GHz to 4.25 GHz; frequency 5.45 GHz to 6.05 GHz; frequency 600 MHz; omnidirectional radiation pattern; ultra-wideband microstrip-fed planar antenna; voltage standing wave ratio;