Design of a low cost and simple wireless battery charging by using repeater antenna technique

A design of a wireless battery charging (WBC) system for a mobile phone device is reported in this paper. The objective of this design is low cost and low complexity of the electronic circuit and antenna system. The E-class power oscillator is chosen because of low complexity and high power efficiency. The Class-E power amplifier integrated with RC clock crystal oscillator is employed. Transmitting coil antennas consist of a resonator coil and feeding coil. The resonator coil receives an electromagnetic energy from feeding coil without any direct connection from a source. The receiving coil antenna is located inside the body of portable devices. It is also interested to design a repeater antenna to extend the distance of charging system. It is found that by using repeater antenna technique the charging distance can be increased.