Design of an RFID-Based Battery-Free Programmable Sensing Platform

Sensing Platform (WISP), which is a programmable battery-free sensing and computational platform designed to explore sensor-enhanced radio frequency identification (RFID) applica-tions. WISP uses a 16-bit ultralow-power microcontroller to per-form sensing and computation while exclusively operating from harvested RF energy. Sensors that have successfully been inte-grated into the WISP platform to date include temperature, ambi-ent light, rectified voltage, and orientation. The microcontroller encodes measurements into an Electronic Product Code (EPC) Class 1 Generation 1 compliant ID and dynamically computes the required 16-bit cyclical redundancy checking (CRC). Finally, WISP emulates the EPC protocol to communicate the ID to the RFID reader. To the authors ’ knowledge, WISP is the first fully programmable computing platform that can operate using power transmitted from a long-range (UHF) RFID reader and communi-cate arbitrary multibit data in a single response packet. Index Terms—Programmable radio frequency identification (RFID), RFID sensors, sensor, transponder, UHF, wireless power. I