Design of a 5.8 GHz Band Omnidirectional High-Efficiency Rectenna for Smart Factory IoT Sensors

This study presents a study on the design of a 5.8 GHz omnidirectional high-efficiency rectenna for IoT sensors in smart factories, aiming for efficient power conversion and stable power transmission in wireless power transfer (WPT) systems. By utilizing an omnidirectional antenna and a metamaterial-based design, the antenna gain was improved from 2.4 to 4.6 dB, and the application of a Class-F harmonic filter enhanced the power conversion efficiency. The antenna and rectifier were integrated into a single module, and the performance of the rectenna was validated through simulations and experiments. The experimental results showed that the rectenna achieved a maximum power conversion efficiency of 72.2 % at 12 dBm input power in the 5.8 GHz band, with a maximum output voltage of 3.86 V. In addition, successful power transmission was achieved over a distance of 1 m through the rectenna. This study provides an efficient wireless power transfer solution for low-power sensor networks in smart factories and IoT environments to ensure high performance.