Cameras powered by Wi-Fi signals could be on their way
The future is here folks; researchers at the University of Washington in Seattle have experimented enough to let us believe that someday our power-hungry cameras and other connected devices would draw their juice from the energy emitted by Wi-Fi signals. A team of researchers led by PhD student Vamsi Talla at the Sensor Systems Lab of the University have been able to beam energy from Wi-Fi signals to power a camera to click pictures. A battery-free surveillance camera was modified to draw power from Wi-Fi signals, store it, and then use it to take photographs.
The team behind this successfully executed project trusts this technique, of using Wi-Fi energy to power devices, would have ample applications including in devices that are believed to form the Internet of Things.
Researchers call their system as power-over-Wi-Fi or PoWi-Fi. During their research, the team realized that energy contained by Wi-Fi signals (omnipresent these days) came close to the voltage required by various low-power devices to operate. Until now the Wi-Fi radio broadcasts are only picked up by Wi-Fi receivers, and the energy almost goes waste; this is why Talla and team believed they could harvest this energy and use it to power a device.
It wasn’t as simple as it looked on the onset; the team realized that Wi-Fi signals are broadcasted in bursts along various frequencies, thus the required useful energy was only available irregularly. To get this fixed, researchers modified Wi-Fi routers and hotspots to broadcast noise when a particular channel was available but not transmitting data. The programming ensured the Wi-Fi signals stayed constant to power the component configured with it.
Being able to harvest consistent power from Wi-Fi signals, the researchers used the energy to run a temperature sensor and a tiny surveillance camera, which were kept a few meters from the Wi-Fi routers. The camera stored Wi-Fi signal energy in its capacitor, which prompted the camera to take a picture when it was completely charged; interestingly the camera was able to click photos every 35 minutes using nothing but Wi-Fi energy.