A novel dual-frequency microwave rectifier at 2.45 and 5.8GHz with harmonic recycling

A novel dual-frequency microwave rectifier that operates at 2.45GHz alone, 5.8GHz alone, or their combination has been developed in this paper. It is the first approach to microwave rectifying for a situation of the incoherent microwave power combination. We focused on the two primary components, i.e. the regulation of impedance matching and the recycling of the second harmonics. A quarter-wave short-ended microstrip line at 5.8GHz is shunted at the input of the rectifier to enhance the impedance matching at 2.45GHz. A microstrip line band-stop filter (BSF) and a quarter-wave short-ended microstrip line are introduced to improve the recycling of the second harmonics. The measured microwave to DC (MW-DC) conversion efficiencies are 57.5, 46.5, and 40.7% at 2.45, 5.8GHz, and their combination, respectively, with an input microwave power at 17dBm. It may be applied to a dual-frequency microwave power wireless transmission system.