AM to PM noise conversion in a cross-coupled quadrature harmonic oscillator
We derive the dynamic equations governing the cross-coupled quadrature oscillator, perturbed by noise, leading to an expression for the close-in phase noise. The theory shows that a nonlinear coupling transconductance results in AM-PM noise conversion close to the carrier, which increases with the coupling strength. A simple linear time-domain model is employed to illustrate the results. (C) 2005 Wiley Periodicals, Inc.
quadrature oscillator phase noise lc oscillators am-to-pm noise conversion nonlinear circuit analysis