Distributed Resistive Up-Converter GaN HEMT MMIC With High LO Suppression for Wideband Applications Up to D-Band

This paper presents an up-converter monolithic microwave integrated circuit (MMIC) based on GaN high-electron-mobility transistors (HEMTs) working over 100 GHz of radio frequency (RF) bandwidth up to D-band (110–170 GHz). A design focus lies on local-oscillator (LO) leakage suppression. The MMIC uses a distributed resistive topology and is fabricated in a 100 nm AlGaN/GaN HEMT technology. The up-converter integrates two distributed mixers driven by a differential LO signal using an on-chip balun. For an input LO power of 5 dBm, the MMIC achieves an average measured conversion gain of -18.8 dB over a broad RF bandwidth of 50–150 GHz with an LO leakage suppression ranging from 23–61 dB. With respect to the RF output power, the LO suppression is between 6–25 dBc. The input- and output-referred -1 dB compression points are 0 dBm and -20 dBm, respectively. To the best of the authors’ knowledge, this is the first demonstration of a GaN HEMT based up-converter operating up to 150 GHz.