All-digital Plug and Play Passive RFID Sensors for Indoor Temperature and Humidity Monitoring.

this paper presents a plug & play, battery-free, and wireless sensor technology to enable low-cost indoor temperature and humidity measurements for energyefficient building controls and operations. The proposed technology is based on the method of all-digital sensing, which powers the sensor to operate without on-node signal processing and battery. By integrating the sensor nodes with the radio frequency identification (RFID) technology, the sensor nodes can be wirelessly interrogated in a "plug & play" fashion. The sensing system was experimentally verified in a BACnet based building management system (BMS).