A 270 GHz CMOS Doubler-Based Up-Conversion Mixer with Output Amplitude Imbalance Detection

We present a doubler-based frequency mixer in 300-GHz band, which is called a square mixer, that can detect the amplitudes of output signals for amplitude imbalance calibration. The proposed square mixer can extract the previously discarded difference frequency components. The detected power can be used for the amplitude imbalance calibration. Furthermore, a stacked amplifier is used for a driver amplifier to increase the output power. The proposed square mixer is fabricated in a 40-nm CMOS process. The square mixer has the output power of –7.7 dBm at 270 GHz. The detected output power is verified by a simulation.