Experimental Analysis of Interference Between 920 MHz WPT and Passive UHF-RFID Systems

In recent years, research on Wireless Power Transmission (WPT) using microwaves has been gaining momentum. Notably, regulatory frameworks for WPT have been established in North America and Japan, facilitating efforts toward its industrial implementation. While practical applications have primarily focused on the 920 MHz band, there remain significant technical challenges related to frequency sharing. This frequency range is also utilized by mobile communication systems and RFID technologies, raising concerns that WPT emissions may exceed permissible power levels both in-band and out-of-band and thereby interfere with these existing systems. To address this issue, we performed a quantitative assessment of the interference potential between WPT and RFID systems. Our experimental results indicate that non-modulated WPT systems substantially reduce the likelihood of interference.