Low Phase Noise Ku-Band VCO With Optimal Switched-Capacitor Bank Design

In this brief, a low phase noise Ku-band voltage-controlled oscillator (VCO) fabricated in a 130-nm BiCMOS process is presented. The phase noise mechanism of the switched-capacitor bank is analyzed, an optimum bank design to reduce phase noise is proposed, and a tradeoff with tuning range is discussed. The prototype 12.2-13.1-GHz VCO achieves a measured phase noise of −120.6 dBc/Hz at 1-MHz offset when running at 12.67 GHz. The VCO core consumes a power of 17.7 mW and attains a figure of merit of 190.