High-efficiency rectifying circuit for 5.8GHz wireless RF energy harvesting applications

Abstract

A high efficiency rectifying circuit with multi-section impedance conversion and harmonic suppression is proposed. A shorted stub is used to compensate the rectifying diode capacitive impedance. Furthermore, a matching filter network is integrated at the DC output port to eliminate the fundamental and high order harmonics which are generated by the diode nonlinearity. The above efforts could effectively improve the conversion efficiency of rectifying circuit. A wireless RF power transmission experiment is implemented, the output voltage is 2.003V with the distance between the transmitting and receiving antenna is1 m. The output voltage is linear with the transmission distance, and the maximum output voltage can reach 3.17V. Experimental results show that the proposed rectifying circuit achieves high rectifying efficiency of 59.6% at 5.8GHz.