SAW-based radioisotope-powered wireless RFID/RF transponder

We demonstrate a microfabricated ⁶³Ni radioisotope-powered RFID transponder realized with a SAW (surface acoustic wave) device as the transmission frequency selector. The transponder is powered by a 1.5 milli-Ci ⁶³Ni source which has a half-life of 100 years. We have achieved a 5mW, 10-μs long, 100MHz carrier envelope, RF pulses which occur every 3 minutes, across a 50Ω load. The optimization of conversion efficiency of the system is studied, and with fingers placed between input and output ports, the mass-loading effects of the devices are also investigated for RFID/RF sensor applications. The transponder can potentially work autonomously for decades, enabling long term reliable sensing and monitoring eliminating the need for battery changing.