Rotman Lens-Based Multibeam Planar Antenna System for UWB IoT Applications

This paper presents a cost-effective and portable multibeam planar antenna system designed to enhance connectivity in Internet of Things (IoT) applications. IoT networks face challenges such as high energy consumption, interference, and inefficient coverage, necessitating innovative antenna solutions. To address these issues, we propose a Rotman lens-based beam-steering antenna system operating in the 7-8 GHz ultra-wideband (UWB) range. The system consists of a three-input, six-output Rotman lens for analog beamforming and a six-element UWB antenna array, enabling the generation of three switchable beams. The fabricated prototype, developed on low-cost FR4 substrate with a thickness of 1.6 mm, achieves a peak gain of 8 dBi in the broadside beam configuration. Simulated and measured results demonstrate good agreement, confirming the efficient beam-steering capability and wideband performance of the proposed system. The design ensures low power consumption while maintaining reliable and adaptive connectivity. These characteristics make it well-suited for real-world deployment in dynamic IoT environments. The findings highlight the potential of Rotman lens-based antennas for low-power, high-performance IoT applications, offering an effective solution for smart industrial and wireless sensor networks.