Monolithic 60 GHz GaAs CW IMPATT oscillator

A monolithic microwave integrated circuit (MMIC) design was developed for GaAs IMPATT diodes to enable their operation under continuous-wave (CW) conditions at V-band frequencies. All impedance-matching circuits were fabricated on the top surface of the GaAs substrate. At 61.5 GHz, 100-mW CW output power was obtained with 13.5% conversion efficiency. In an alternative design, varactor diodes were integrated with the IMPATT circuits to produce the first monolithic VCOs operating under CW conditions. Over 3.5 GHz of tuning bandwidth was obtained at a center frequency of 70-GHz with a CW output power of 15 mW.<
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