Miniature Multiband Inverted‐F Antenna over an Electrically Small Ground Plane for Compact IoT Terminals

Abstract

This paper describes the design of a miniaturized multiband Inverted‐F Antenna (IFA) suitable for integration in compact Internet‐of‐things (IoT) terminals. The antenna efficiently operates over the LoRa (915 MHz) and GPS L1 (1.57 GHz) and L2 (1.23 GHz) bands. Its dimensions are 13 × 25 × 1 mm 3 (0.04 λ × 0.08 λ × 0.003 λ compared to the lower operating frequency) for a total device size of 40 × 25 × 10 mm 3 . Measurements of the antenna when integrated into an IoT position tracking device as well as of the whole terminal in a real application scenario are reported.