25 May 2004 Phase noise in a Colpitts oscillator
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Proceedings Volume 5470, Noise in Devices and Circuits II; (2004) https://doi.org/10.1117/12.549267
Event: Second International Symposium on Fluctuations and Noise, 2004, Maspalomas, Gran Canaria Island, Spain
We apply the technique of the calculus of stochastic differential equations to the problem of noise in an electronic circuit with positive feedback. We argue that this is a very natural approach to the more general problem of noise in electronic circuits of all types. We apply the standard small-signal analysis to the circuit, incorporating the standard high-frequency small-signal model for the field effect transistor. This allows us to derive a state-variable model for the system, which is essentially a coupled system of Ordinary Differential Equations. If we then incorporate a standard noise model for the field effect transistor, we obtain a coupled system of Stochastic Differential Equations, or SDEs. We apply the stochastic differential calculus of Ito to this problem and compare the results with simulations. We examine the dependence of phase-noise on the system parameters. We also simulate the case where the oscillations become large and use this to investigate the limits of the small-signal approximation.
© (2004) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Andrew G. Allison, "Phase noise in a Colpitts oscillator", Proc. SPIE 5470, Noise in Devices and Circuits II, (25 May 2004); doi: 10.1117/12.549267; https://doi.org/10.1117/12.549267

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