Radio transmitter without batteries demonstrated by scientists

Scientists at University of Washington shows a battery-less radio transmitter.

Image source: University
of Washington

A group of scientists have recently built and demonstrated a radio transmitter that can operate without battery power. The radio transmitter working principle is based on the ambient back-scatter technology.

By using the ambient back-scatter technology, the transmitter can harness the energy from surrounding radio waves, such as TV signals and Wi-Fi signals, and subsequently power itself to transmit its own radio signal. 

Of course the amount of energy in the ambient radio waves are very limited, and therefore the transmitters are required to be extremely energy efficient. This, however, is very possible today, although in general the amount of information and the transmission speeds will be limited using this technology.

The scientists, nonetheless, have big hopes in this green technology which should be appealing to many people as it can harness the ambient radio waves energy which otherwise would primarily be lost anyway. It is envisioned that the device can be used in future portable devices such as smart watches and smart sensors.