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 (110−170GHz). 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 50−150GHz 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.