K-band CMOS High-Power Harmonic Response Rectifier for Nonlinear Detection based Wireless Power Transfer
This paper presents a K-band CMOS harmonic response rectifier based on 2-stage cross coupled bridge rectifier. The proposed CMOS harmonic response rectifier configured with rectification stage and second harmonic output stage can be used for nonlinear detection based wireless power transfer. The transformer in the rectification stage did not only generate differential signal but also matched to 50 ohm at a fundamental frequency to achieve low insertion loss. To maximize conversion gain, the second harmonic stage was matched to 50 ohm at second harmonic frequency. The proposed CMOS harmonic response rectifier was designed using a 65 nm CMOS process and had a chip area of 0.35 mm x 0.22 mm. The simulation results show that the power conversion efficiency (PCE) was 15.2–20.2 %, and the conversion gain (CG) was -23–-21.2 dB at an input power of 25.5 dBm in the frequency range of 20.5–27 GHz.