Dual band-notched UWB antenna based on spiral electromagnetic-bandgap structure

Abstract

An ultra-wideband (UWB) printed monopole antenna with dual band-notched characteristics is proposed. Two spiral electromagnetic-bandgap (EBG) structures placed on the front and back side of the substrate are employed to create two notch bands at 5.2 and 5.8 GHz for the lower and upper bands of the wireless local-area network (WLAN), respectively. The notch-frequency can be tuned, and the band width is narrow and adjustable. Furthermore, the spiral EBG structure used in this design are more compact than conventional mushroom-type EBG. Equivalent circuit model is extracted and discussed to explain the operating mechanism of this structure. The proposed antenna has been simulated and measured in both the frequency domain and time domain, good agreement between calculated and experimental results has been achieved.