A 19 GHz low phase noise HFET VCO MMIC

A 19 GHz extremely low phase noise voltage controlled oscillator (VCO) MMIC is presented. To reduce the phase noise of the VCO, a heterostructure field effect transistor (HFET) is used as the active device, because its low frequency noise properties are superior to that of high electron mobility transistors (HEMT). This VCO showed a typical phase noise of -120 dBc/Hz at 1 MHz offset from the carrier. This performance is better than other VCOs operating above 10 GHz. The measured tuning range is 400 MHz and output power is 2 dBm. The fabricated MMIC chip size is 2.7 mm/spl times/1.4 mm.