Solar-Powered Wireless Temperature Sensor Based on UWB RFID With Self-Calibration

This paper presents a solar-powered wireless temperature sensor based on time-coded ultrawideband (UWB) radio frequency identification. A negative temperature coefficient resistor acts as the sensing element. It controls the current of a PIN diode connected to a UWB scattering antenna. The wireless sensor is self-calibrated using a narrowband tone, making its performance independent of the distance or orientation between the reader and the sensor. A consumption of 82 μA is demonstrated. An error under 0.6 °C within a 35 °C-70 °C temperature range is obtained for most of the cases.