Closed-loop spurious tone reduction for self-healing frequency synthesizers

F. Bohn, K. Dasgupta, and A. Hajimiri

On-chip spurious tone detection and correction in an 8-12 GHz CMOS synthesizer is used to automatically reduce spurious output tones at different offset frequencies by up to 20dB. Using synchronous detection, sensitivity is limited by detection time only. The presented methods are generally applicable to frequency synthesizers and phased-locked loops in various applications.