Array Antenna System for Wireless Power Transfer (WPT) System at 6.78 MHz

This paper proposes an array antenna system for wireless power transfer (WPT) at 6.78GHz. The development of new techniques to increase power transmission and covered area is proposed. The power transmitter with a power output of 22-60 W is designed. Using the principle of magnetic resonance technique, the transmitting array antenna consists of 4 antennas and arranged in the same plane. The in-phase signal feeding technique is selected. Therefore, the electric field spreads around the array transmitting antenna. Measurement results found that the maximum received power of 9.4W. The average value is 3.5W which is sufficiently used to charge the batteries. Charging time depends on the position and received power.