A 17.5-dBm Output Power 11.2% DC-to-RF Efficiency Low Phase Noise CMOS Quadrature Voltage-Controlled Oscillator
This paper describes a high-power high-efficiency quadrature voltage-controlled oscillator (QVCO) in 0.18 µm CMOS process. Four cascode gain cells with back-gate coupling are employed in the core of the QVCO to achieve high power and high efficiency. When the oscillation frequency is from 9.32 to 9.5 GHz, the proposed QVCO demonstrates a maximum output power of 17.5 dBm, an efficiency of 11.2%, and a phase noise of -125.7 dBc/Hz at 1 MHz offset. The measured minimum amplitude and phase errors are within 0.28 dB and 0.6°, respectively. The work has the highest output power among all the reported CMOS QVCOs, and also it achieves excellent figure-of-merits.