MEMS based antenna of energy harvester for wireless sensor node

This paper deals with glass surface micromachined antenna of RF energy harvesting for wireless sensor node applications. The research aims to provide a system based on a new integrated RF energy harvester circuitry using a transparent receiving antenna by micromachining process. The energy harvester system is studied using CST-MWS software by Pyrex glass as the antenna substrate having dielectric constant ɛ_r = 4.6. Besides, PSpice and Cadence analyze the DC output solutions. The fabrication of the micromachined antenna based on metal patterning of the radiator patch and metal sputtering on the top and bottom of the glass surface, respectively. The analysis of the wave propagation of the antenna shows good agreement between the simulation solutions and experimental validations. It is present that the antenna achieved a maximum gain of > 4 dB, reflection coefficient (S₁₁) < − 10 dB, wide − 10 dB bandwidth of > 100 MHz, omnidirectional radiation pattern and VSWR ratio < 2. From DC analysis, with an ultra-low input power of − 20 dBm incoming from this optimal antenna, the MOSFET rectifier reaches an efficiency of 46.23% and DC output voltage of 2.15 V at 1 MΩ load. Further, the developed antenna integrated into the RF energy harvester on the same circuit platform that yield a highly efficient operating system at 5 GHz ISM band.