We can get power from current. Here we would be getting that power from Microwaves that we use for our mobile communication. The power transmission would start with Ac-Dc conversion, followed by a Dc-RF/Microwave conversion through a magnetron at the transmittet side. After propagating through the air, the microwave captured by the receiver antenna i.e. mobile phone is converted back to Dc to charge the battery of the mobile. For higher efficiencies, a sharp beam can be generated through an antenna array.