Temperature beat: Persistent and energy harvesting wireless temperature sensing scheme

This paper presents a persistent and energy harvesting wireless temperature sensing scheme. Every time when the voltage is stored in a storage capacitor, the RF module transmits ID code to a receiver. The transmission of only ID code is called as “Temperature Beat”, the cycle time of which corresponds to temperature. Time between Temperature Beat represents average temperature, so that it is not an intermittent but a persistent sensing. The size of the sensor node is 50 × 35 × 15mm and the energy for transmitting one Temperature Beat is 0.43mJ. Solar cell with lithium ion battery can be used to achieve energy harvesting operation. In experiments, this system can measure −21 ∼ 90 degree C with accuracy of ± 0.655 degree C with consuming 1.38mJ to transmit one Temperature Beat.