A CLASS-C QUADRATURE VCO USING THE VARACTOR COUPLING TECHNIQUE

摘要

This letter presents a 2.1 GHz Class-C quadrature voltage-controlled oscillator (QVCO) working on coupling two identical Class-C VCOs. The class-C oscillator is used to achieve the performance of low phase noise. The QVCO uses a varactor ring to generate quadrature phase and it was implemented using the TSMC 0.18 mu m CMOS 1P6M process. The output phase noise of the QVCO is -130.34 dBc/Hz at 1 MHz offset frequency from the output carrier frequency of 1.978 GHz; the quadrature phase error is 0.33 degrees and the figure of merit is -190.61 dBc/Hz. Total power consumption is 3.9 mW. Tuning range is about 422 MHz (19%) between 1.978 and 2.4 GHz, while the control voltage was tuned from 0 V to 2 V. The die area is 0.528 x 1.168 mm(2). (C) 2016 Wiley Periodicals, Inc. View this article online at wileyonlinelibrary.com.