A 48 mu W, 8.88 mW/W Batteryless Wirelessly Power Transferred Body Channel Communication Identification System

Abstract

A BCC identification (BCC ID) which is fully compatible with previous radio frequency identification (RFID) is newly proposed with verifying wireless BCC power transfer by off-the-shelf board. The off-the-shelf board shows possibility of BCC power transfer by turning LED on with transferring RF wave wirelessly with 15 cm distance. The BCC ID is composed of a reader and a tag. The reader transmits RF wave for power generating and receives identification code and authorizes. The tag transmits energy and transfers identification code. The power transmitter in the BCC identification tag increases power conversion efficiency (PCE) by up to 12% by adaptively changing number of rectifier stages depending on input power. In addition, a transformer reusing phase shift keying (PSK) modulation is proposed to inform the reader of completion of power transferring of the tag by changing load impedance. As a result, a 48 mu W, 8.88 mW/W Figure-of-Merit (FoM) BCC identification system is implemented. This system can generate sufficient power in the tag with lower transmitted power from the reader compared to previous RFID.