Compact multiband monopole antenna design for IoT applications
Saminathan Thiruvenkadam, P. Eswaran
Abstract
In this work, a miniaturized quad-band monopole antenna design is presented for IoT applications. The proposed antenna comprises simple quarter-wavelength I-shaped, an inverted L-shaped, meander lines monopole radiators with microstrip feed line, tapered ground plane having dimension of 32×15mm2 and fabricated on an FR4 substrate. The radiation characteristics, such as reflection coefficient, VSWR, gain, efficiency, and radiation patterns, are analyzed from simulation and measurement results. The proposed quad-band antenna resonates at 1.8 (1.7–1.96) GHz, 2.4 (2.26–2.47) GHz, 3.35 (3.1–3.7) GHz, and 5.4 (5-5.65) GHz for GSM, WLAN, 5G, WiMAX applications respectively. Further, the proposed antenna has a fractional bandwidth of 14.4% at 1.8 GHz, 8.75% at 2.4 GHz, 17.9% at 3.35 GHz and 12.03 % at 5.4 GHz. It also exhibits omnidirectional radiation pattern with a gain of 1.5, 1.75, 2.5, and 3.7 dbi at 1.8, 2.4, 3.35, 5.4 GHz respectively and >75% total efficiency at its operating bands. The suitability of the designed antenna for IoT applications is validated through the hosting device model with copper sheet and plastic housing. The simulation and measurement results are having good agreement.