A Tri-Port Wearable Tag for Indoor Communication with Power Delivery Through Near-Field and Far-Field Energy Harvesting

This work introduces an innovative hybrid simultaneous wireless information and power transfer architecture that integrates both near-field and far-field wireless power transfer mechanisms into a single compact receiving tag. The system features a dual-mode energy harvesting design: a resonant coil operating at <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\text{1 3. 5 6 ~ M H z}$</tex> for efficient near-field power transfer, and a cross-polarized antenna system for far-field energy harvesting and data communication in the 2.4 GHz band. The antenna employs a dual-fed configuration that combines coaxial and microstrip feeding techniques, optimizing radiation performance and polarization diversity for robust communication. Detailed electromagnetic simulations are corroborated by antenna and power transfer measurements, which demonstrate the effectiveness of the design. This multifunctional tag is tailored for low-power applications such as Internet of Things devices, radiofrequency identification systems, and wireless sensor networks, offering a highly integrated solution for simultaneous energy acquisition and wireless data transmission.