Microwave power transfer evaluation at 2.45 GHz using a high-efficiency GaAs HEMT amplifier and rectifier

Microwave power transfer has been evaluated at 2.45GHz by using a high-efficiency InGaAs/GaAs pHEMT amplifier and rectifier. The same type of HEMT and harmonic treatment circuit were used for both the amplifier and the rectifier. Harmonic reactive terminations up to the fifth order were applied to the harmonic treatment circuits to obtain a high-efficiency characteristic. The fabricated amplifier and rectifier delivered a maximum drain efficiency of 78% and a maximum RF-to-DC efficiency of 77% at 2.45 GHz, respectively. In addition, a total DC-to-DC efficiency of 57% for the microwave power transfer via a 0.5-m coaxial cable was obtained by using the fabricated amplifier and rectifier.