High Efficiency Rectifier with Extended Operating Input Power Range

A novel rectifier with wide input power range is proposed, which is designed by branch-line coupler. It contains three sub-rectifiers, two of them work at high power level as main branches and another one works at low power level as power recycling branch. The impendance of main branches will be mismatched when it works at low power and the power is reflected to power recycling branch. Consequence, in a wide power range, the rectifier will maintain high efficiency. Theoretical analysis and experiment are both carried out. The measured efficiency of a 2.45 GHz rectifier can over 500% from 8.5 to 32.5 dBm.