Researchers Turn Radio Waves Into Electricity To Power Your Smart Watch

Smart wearables are the next big thing after smartphones. These fitness bands come equipped with the tiniest of biomedical sensors to measure your sleep, heart rate, blood oxygen level and can even detect body temperature and irregular heart rhythm. Just strap it on your wrist and get detailed health stats. But there's a catch: you need to juice it up time and again--just like your laptop, smartphone, headphones and what not.

Meanwhile, a team of researchers claimed to have developed a ¡°disruptive technology¡± to harvest energy from radio waves that could power wireless wearable sensors for patient self-monitoring and daily healthcare.

Reuters

How does the system work?

For the study, published in the journal Materials Today Physics, the researchers developed a stretchable wideband dipole antenna system capable of wirelessly transmitting data that is collected from health-monitoring sensors.

The system¡¯s wideband design allows it to retain its frequency functions even when stretched, bent and twisted. And when this system is connected to a stretchable rectifying circuit, it creates a rectified antenna, or "rectenna,¡± that can convert energy from electromagnetic waves into electricity. This electricity can be used to power wireless devices or to charge energy storage devices, such as batteries and supercapacitors.

Larry Cheng

Next step is creating a miniature version

The technology as demonstrated by the Penn State researchers will continuously harvest a small amount of energy as long as the wearer is in an area with plenty of ambient radio waves, as most urban locations are.

¡°We are utilizing the energy that already surrounds us ¡ª radio waves are everywhere, all the time,¡± lead researcher Huanyu ¡°Larry¡± Cheng said. ¡°If we don¡¯t use this energy found in the ambient environment, it is simply wasted. We can harvest this energy and rectify it into power.¡±

However, he added that the team will be ¡°exploring miniaturized versions of these circuits and working on developing the stretchability of the rectifier¡±.

Notably, there are already solar-powered smartwatches in the market but these can only harvest energy when exposed to the sun. ¡°We don¡¯t want to replace any of these current power sources,¡± Cheng said. ¡°We are trying to provide additional, consistent energy.¡±