Dutch researchers have created a tiny temperature sensor powered entirely be radio waves that could revolutionise smart building infrastructure.
The sensor requires neither batteries nor wires, doing away with the major obstacles for more widespread adoption of Internet of Things technology in the built environment. All the sensor needs is a wireless network.
Merely two square millimetres in diameter and about as heavy as a grain of sand, the temperature sensor has been described as the world’s smallest.
The team from Eindhoven University of Technology squeezed a tiny radio antenna into the minuscule device that receives radio waves from a tailor-made router to use as energy.
The sensor stores the energy and, once there is enough, it switches on, measures the temperature and sends a signal back to the router.
The signal has a distinctive frequency, depending on the temperature measured, which is interpreted by the router.
Although the current version of the sensor only has a range of 2.5cm, the researchers believe they will be able to extend that into a meter within a year and ultimately achieve up to five meters.
The energy-efficient sensors could be placed under a layer of paint, plaster or concrete without it affecting their performance.
According to Peter Baltus, Professor of wireless technology at the Eindhoven University of Technology, the radio wave-powered sensors offer an ideal solution for smart buildings of the future that will have every aspect of their operations regulated by sophisticated systems capable of recognising the actual needs of their occupants.
Battery-requirements are seen as a major obstacle in such buildings riddled with hundreds and thousands of such sensors.
Similar technology could be used to make sensors measuring movement, light or humidity or even systems for wireless identification.
The researchers estimate that once mass-produced, the sensors wouldn’t cost more than 20 cents per piece.