A D-Band I/Q Drain Mixer for Direct Up-convertion in 70-nm GaAs Technology

An I/Q up-conversion MMIC that works in the D-band with the 70nm mHEMT GaAs process is designed in this paper, using a transistor drain mixing unit. The mixer can maintain good performance in the 125-155 GHz frequency band. Without adding any pre- or post-amplifier, the measured conversion gain is -8 dB, the input IF bandwidth exceeds 10 GHz and the isolation between ports is greater than 20 dB. It maintains good linearity under the IF input power of less than 2dBm. The performance parameters of this upconverter are predominant among the GaAs mHEMT-based mixers reported in this frequency band.