Active frequency-tripler MMICs for 300 GHz signal generation

Two frequency-tripler monolithic microwave integrated circuits (MMICs) reaching sub-millimeter-wave output frequencies of 315 GHz are presented. The convenient integration of transistor-based field effect transistor (FET) frequency multipliers into multifunctional MMICs is shown by integration of a single-stage frequency-tripler with a buffer amplifier generating -0.5 dBm of peak output power at 288. Without post-amplification an average output power of -10.1 dBm in the output frequency range from 285 to 315 is measured with 10 dBm of input power. The 3-dB bandwidth is more than 30 GHz and could not be determined exactly due to the measurement setup. Both MMICs are realized in a 50 nm metamorphic high electron mobility transistor (HEMT) transistor technology. A multiple power-meter measurement technique including a waveguide filter is used to measure accurately the second harmonic power content within the output spectrum.