A phase noise reduction technique in microwave oscillator using high-Q active filter

Abstract

This letter presents a 10-GHz oscillator that uses a high-active filter to reduce the phase noise. The loaded of active filter is obtained at about 500. This oscillator is compared with another oscillator which uses a passive filter. The difference of two oscillators' is estimated at 12.5 times the open-loop gain simulation. The measured result of phase noise at 100-kHz offset shows maximum 10-dB reduction with high-active filter.