High Efficiency GaN HEMT Power Amplifier/Rectifier Module Design Using Time Reversal Duality

A general design theory for high efficiency microwave power amplifiers and rectifiers is presented using the time reversal duality concept. Effective techniques for achieving high efficiency microwave power amplifiers can also be implemented in the design of high efficiency rectifiers. As a design example, a harmonic reactive load type (class-R) GaN-HEMT power amplifier and its time reversed dual rectifier were developed at 5.4GHz. The fabricated amplifier delivered a maximum drain efficiency of 82%, whereas the rectifier presented 78% power efficiency. A DC-DC conversion efficiency of 47% was measured with the pulse-width modulation (PWM) technique for a wide dynamic power range of 90 mW to 860 mW.