A High-Dynamic-Range BroadBand MMIC GaN Mixer for Microwave Conversion TX/RX

This paper presents a wideband, high-performance monolithic microwave integrated circuit (MMIC) mixer fabricated in a 150-nm Gallium Nitride (GaN) technology from the UMS Foundry. The design addresses the inherently high local oscillator (LO) drive requirement by integrating a dedicated driver amplifier with a field-effect transistor (FET) ring mixer core. The compact MMIC, measuring 3.9 x 3 mm2, implements a novel dual-core architecture: an up-converter (transmit mode) with a differential radio frequency (RF) port for improved spurious rejection, common-mode noise immunity, and balanced drive capability; and a down-converter (receive mode) with an integrated balun providing a single-ended RF interface, thereby simplifying integration with low-noise components while reducing power consumption and die area. Measured results demonstrate excellent performance over a 2.5–21 GHz RF bandwidth (3:1 octave ratio), with conversion loss below 10 dB across a DC to 6 GHz intermediate frequency (IF) range. The circuit achieves port isolation greater than 30 dB and a noise figure below 10 dB. Owing to its complete high-drive mixer core and GaN’s inherent robustness, the proposed solution is particularly suited for high-performance and high-reliability systems requiring stringent integration and power-handling capability.