A Novel Snail Shell Inspired Wideband Fractal Antenna for Internet of Things Applications

This paper proposes a four-level iterated snail shell-inspired wideband microstrip fractal patch antenna for Internet of Things (IoT) applications. The antenna comprises a snail-shell-inspired radiating patch, a metallic partial ground plane with a notch, and a microstrip feedline. A modal study has been performed with the help of Characteristics Mode Analysis. The notch and partial ground plane contributed to separating the overlapping modes and reducing the quality factor, which enhanced bandwidth. In order to excite multiple modes and to attain the wider bandwidth, the surface current distribution for various modes has been examined. The antenna uses a low-cost FR-4 substrate with a dielectric constant of 4.4 and a 1.6 mm substrate height. The overall dimensions of the antenna are 40 mm × 40 mm × 1.6 mm. The proposed antenna operates between 2.2 GHz and 5 GHz, with a radiation efficiency of 92%, an impedance bandwidth of 166%, and a peak gain of up to 2 dBi. The simulated antenna performance in terms of S11, VSWR, and gain has been validated using Vector Network Analyzer (VNA) measurements in an anechoic chamber. At 2.4 GHz, an omnidirectional radiation pattern has been observed. The proposed antenna covers Wi-Fi 802.11 standard 2.4 GHz, WiMax (2.5 GHz to 2.7 GHz), WLAN (2.4 GHz–2.48 GHz), 5G (3.6 GHz), and Avionics (4.9 GHz, 4.2 GHz to 4.4 GHz), Industrial Internet of Things (IIoT) in 2.4 GHz applications.