Ka-Band CMOS ×5 Frequency Multiplier With Current-Reuse Technique

In this study, we propose a
Ka
-band
$\times 5$
frequency multiplier implemented through a 65-nm CMOS process. The frequency quintupler core is merged with the common-source (CS) amplifier in a current-reuse structure to achieve low power consumption. To further improve harmonic suppression, the interstage matching network of the frequency quintupler core is constructed using a third-order high-pass filter (HPF). The proposed quintupler core was implemented as a high conversion gain
$\times 5$
frequency multiplier along with input/output buffer and notch filter. The size of the proposed
$\times 5$
frequency multiplier was
$0.81\times0.95$
mm, including the input and output buffers. Furthermore, the measurement results of the
$\times 5$
frequency multiplier showed that the conversion gain for the 27.3–28.6 GHz range was 30.7–31.3 dB at input power values of −34 dBm, and the harmonic suppression is in the 30.9–37.5 dBc. In the operating frequency band, the input and output return losses are greater than 10 dB, and the power consumption was 23 mW.