Log-Spiral Antenna Integrated with GaAsSb-Base Backward Diodes for Microwave Energy Harvesting

This paper describes microwave energy harvesting using of a log-spiral antenna integrated with GaAsSb-base backward diodes. We constructed a nonlinear model of a backward diode from the measured I-V and S-parameters. We then used the model to investigate the size of the diode and the number of stages to be used for the rectifying circuits to maximize the output voltage. We designed, fabricated and measured log-spiral antennas integrated with these rectifying circuits. The developed rectenna exhibited 1 V from irradiated RF sources, which is successfully charged up to 3V with a DC-DC converter. The rectenna is a promising candidate for microwave energy harvesting.