A transformer-feedback quadrature voltage-controlled oscillator using a transconductance tuning technique

This paper presents a transformer-feedback quadrature voltage-controlled oscillator (QVCO) using a transconductance tuning technique in 0.18-um CMOS process. The proposed topology uses integrated transformers to produce quadrature phase and employ a transconductance tuning technique for frequency tuning. The measured phase noise is -101dBc/Hz similar to -104dBc/Hz at 1-MHz offset. The tuning range is from 5.97GHz to 6.81GHz, achieved by the control voltage from -0.9V to 0.9V. The measured phase error of the QVCO is below 2.2 degrees. The power consumption is 8.44mW similar to 17.88mW and the figure of merit (FOM) is -167.3 similar to -168dB.