A Fully-Integrated W-Band I/Q-Down-Conversion MMIC for Use in Radio Astronomical Multi-Pixel Receivers

In this paper, a W-band I/Q-down-conversion monolithic microwave integrated circuit (MMIC) is presented. The MMIC is based on the Fraunhofer IAF 50-nm gate-length metamorphic high-electron-mobility transistor technology and contains an RF 3-dB quadrature coupler, two subharmonically-pumped mixer cells, two IF low-noise amplifiers, and an LO chain including a frequency tripler, a band-pass filter, and two power amplifiers. The nonlinear circuits use an anti-parallel Schottky diode topology. The circuit covers an RF and IF bandwidth from at least 75 to 110 GHz and 3 to 13 GHz, respectively. The MMIC exhibits a single-sideband conversion gain of up to 17 dB and an average double-sideband noise figure in the range of 14.2-15.4 dB. The input-referred one-decibel compression point is up to -7 dBm. To the best of our knowledge, the presented W-band I/Q-down-conversion MMIC demonstrates state-of-the-art results with regards to complexity and performance.