G-band metamorphic HEMT-based frequency multipliers

Two monolithic G-band active frequency multipliers have been designed and fabricated using coplanar-waveguide technology. The monolithic microwave integrated circuits are a frequency tripler for an output frequency of 140 GHz and a 110-220-GHz frequency doubler. The tripler demonstrates a maximum conversion gain of -11 dB for an input power of 9 dBm, whereas the doubler achieves a conversion gain of -7 dB for a 2.5-dBm input signal. The circuits have been realized using two InAlAs/InGaAs-based metamorphic high electron-mobility transistor processes with different gate lengths of 100 and 50 nm, respectively.