Innovative Ultra-Wideband (UWB) Antenna with Folded Stepped Impedance Resonators

This article proposes a new ultra-wideband (UWB) antenna with twin sharply rejected notch bands that sizes just
$18 \text{mm}\ \mathrm{x}28 \text{mm}\ \mathrm{x} 1$
mm in total dimension for dual-band WLAN applications. The antenna construction is optimized for dual-band operation, ensuring a consistent bandwidth. Optimizing the length of Path 1 may fix the antenna resonance in the desired WLAN band, whilst tuning the length of Path 2 (as shown in the identical Figure) attempts to fix another WLAN band resonance. Two short-circuited folded stepped impedance resonators (SIRs) and a slightly truncated ground plane were proposed to accomplish the band rejection feature; the compact folded SIRs are positioned next to the feed line. The right-side branch of the antenna has a tiny slot integrated in it to achieve the requisite resonance electric length while also reducing the antenna's overall size. The proposed antenna is constructed on a 1 mm thick FR 4 substrate with
$\varepsilon \mathrm{r}=4.3$
. The measured results indicate dual-band operations satisfactory, with −10 dB impedance bandwidths of 9.1% and 36.2%, respectively, centered at 2.45 and 6.364 GHz and spanning the WLAN operational bands. Considering the performance parameters, this proposed Folded Stepped Impedance antenna has been optimized to enhance radiation patterns and antenna gains throughout the operation bands.