A 210 GHz dual-gate FET mixer MMIC with > 2 dB conversion gain, high LO-to-RF isolation, and low LO-drive requirements

We demonstrate the first active mixer monolithic microwave integrated circuit (MMIC) with Positive conversion gain beyond 200 GHz. The presented dual-gate topology is realized in a 100 nm gate length metamorphic high electron mobility transistor technology. Without any pre- or post-amplification, the down-conversion mixer achieves >2 dB conversion gain and >16 dB local oscillation to radio frequency (LO-to-RF) isolation at 210 GHz, outperforming state-of-the-art resistive MMIC mixers. The conversion gain becomes positive for LO power levels larger than 0 dBm, making the mixer suitable for being driven by an MMIC-based frequency doubler. A comparison to state-of-the-art G-band mixers is given.