Efficient microwave rectifier over wide input power range for wireless energy transfer

This paper presents a novel rectifier topology in an attempt to extend its operating input power range. With the addition of n-channel Field Effect Transistor (n-FET) that acts as an adaptive switch, the rectifier is able to adjust automatically between low and high input power modes and remains efficient over a wide input power range. A 1-GHz prototype is designed and the measurement shows that the efficiency level stays above 50% from −4 dBm to 20 dBm, and achieves peak efficiency of 81% at 17 dBm of input power.