A G-Band Frequency Doubler in 40-nm Digital CMOS for THz Applications

This paper presents a G-band CMOS frequency doubler for THz applications. The transistor’s inherent even nonlinearity is employed to realize the frequency multiplier function. A transformer balun is designed to give the required differential input driving signal with low phase and amplitude imbalance. Input and output impedance matching networks using transmission lines are designed to provide and extract the maximal input and output power to and from the nonlinear transistors at 85 and 170 GHz, respectively. Realized in a 40-nm digital CMOS technology, the proposed frequency doubler can exhibit measured conversion gain of -17 dB and output power of -7.8 dBm at 182 GHz while owning 3-dB bandwidth from 154 to 206 GHz. The power dissipation is only 38.7 mW from a 0.9-V supply.