Generator unit for wireless power transfer

An RF signal generator adapted to wirelessly transfer power to a first wireless device, said RF signal generator comprising:

• a first plurality of generating elements each adapted to generate an RF signal, the plurality of the RF signals being transmitted by a first plurality of antennas;
• a wireless signal receiver;
• and
• a control unit adapted to control a phase of the RF signal generated by each of the first plurality of RF signal generating elements in accordance with a first signal the receiver receives from the first wireless device, said first signal comprising information representative of an amount of RF power the first wireless device receives, wherein said RF signal generator further comprises a second plurality of generating elements each adapted to generate an RF signal, said first and second plurality of generating elements each adapted to generate an RF signal in accordance with a reference timing signal supplied by the control unit to the first and second plurality of generating elements using at least one electrically conductive wire.