A wirelessly-powered passive RF CMOS transponder with dynamic energy storage and sensitivity enhancement

A scheme for a wirelessly-powered passive sensor is presented in which the extra received power beyond the sensitivity level is stored and later used to enhance the sensitivity of the wireless sensor. A prototype chip has been designed and fabricated in a 0.13 μm CMOS technology. The measurement results show that the aforementioned energy storage mechanism improves the sensitivity of the wireless sensor from -19.5 dBm to -29 dBm at 900 MHz and from -15.4 dBm to -26.5 dBm at 2.4 GHz.