A UHF PASSIVE SENSING LINK IN A NEAR-FIELD WIRELESS POWER TRANSFER SYSTEM

This paper is based on the results obtained during a high-apprentice PhD carried out with the University of Bologna and IMA SpA, Bologna, Italy. It focuses on a nonconventional exploitation of a self-resonant near-field link at UHF for data communication, to be combined in a compact inductive wireless power transfer system. At LF, the inductive channel is designed to deliver up to 1.3 kW to a resistive rotary heater. At UHF, sensing capabilities are made possible by exploiting self-resonant structures, such as split-ring resonators, one at each far-end side of the link. This network is used in a passive sensing system, to convert the data of a remote temperature sensor, representing the system variable load. The reflected power variations at the transmitter side, due to the dc load variations, are successfully used to perform the sensor readout