Low Phase Noise Wide Tuning Range LC Oscillator for RF Application Using Varactor Bank.

Pradeep Rajpoot, R. C. Gurjar, R. S. Gamad


This paper presents the design of a QVCO (Quadrature voltage controlled oscillator) with high tuning range and low phase noise for Radio Frequency applications. The proposed VCO has been designed to produce quadrature signal by using cross coupled topology. Extra pair of MOSFETS are added to improve the quality factor of the LC tank, which helps to improve the phase noise. The tuning range of VCO ranges from 3.8 GHz to 4.52 GHz, which is nearly 20%. Additionally, the obtained phase noise is -120.31 dBc/Hz at 1MHz offset frequency. The observed power dissipation is 13.21 mW.


Dual Pair Cross Coupled, Phase Noise, Power dissipation, Quadrature LC VCO, Tuning Range;

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