Compact loop-type antenna with ground-mode tuning for dual-band IoT applications

Abstract

A compact dual-band loop-type antenna is proposed in a small-sized ground plane for Internet-of-Things (IoT) applications. The antenna element is comprised of two adjacent resonance loops, excited by two feeding loops at the back side of the substrate, to achieve independent control of dual-band IoT applications at 0.92 and 2.45 GHz, respectively. To improve the radiation performance of the lower band, the metal frames are adopted as ground-mode tuning structures to generate a new ground-mode resonance, producing dual-resonance characteristics at 0.9 GHz bands and generating greatly improved bandwidth and radiation efficiency. Therefore, both lower and higher bands with high performances are achieved in simulation and verified in measurement.