A wireless charging technology that can charge devices from 5 metres away

London: What if you are told you can charge your smartphone even if the power source is some distance away on a street or inside a restaurant?

Taking the wireless technology one step ahead, researchers have removed the last remaining wires altogether by developing wireless power transfer technology.

The result is Dipole Coil Resonant System (DCRS) that can charge 40 smart phones simultaneously, even if the power source is 5 metres away.

"With DCRS, a large LED TV as well as three 40 watt fans can be powered from a 5-metre distance," said Chun T Rim, a professor of nuclear and quantum engineering at Korea Advanced Institute of Science and Technology (KAIST) in South Korea.

The technology proved the possibility of a new remote power delivery mechanism that has never been tried at such a long distance.

"Just like we see Wi-Fi zones everywhere today, we will eventually have many wi-power zones at such places as restaurants and streets that provide electric power wirelessly to electronic devices," Rim hypothesised.

We would use all the devices anywhere without tangled wires attached and anytime without worrying about charging their batteries, he added.

To build the system, the KAIST research team used compact ferrite core rods with windings at their centres.

The high frequency AC current of the primary winding generates a magnetic field and then the linkage magnetic flux induces the voltage at the secondary winding, the researchers said.