A K-band low power high accuracy quadrature VCO using gate-modulated coupling and transformer feedback technique

This paper describes a low power high accuracy K-band quadrature voltage controlled oscillator (QVCO) in 90 nm CMOS process. The gate-modulated coupling and the transformer-feedback technique are employed in the QVCO design to enhance performance. With a dc power consumption of 16 mW, the measured tuning range is from 23.4 to 25.1 GHz, and the output power is higher than −5 dBm. The measured phase noise at 1-MHz offset is −98.6 dBc/Hz. The measured minimum phase and amplitude errors are 0.28° and 0.55 dB, respectively. The chip size is only 0.74×0.89 mm².