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Design >> RF Design >> Phase noise derivation in Book “High-Purity Oscill
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Message started by neoflash on Dec 26^th, 2006, 4:46am

Title: Phase noise derivation in Book “High-Purity Oscill
Post by neoflash on Dec 26^th, 2006, 4:46am

Phase noise derivation in Book “High-Purity Oscillators” (A.A.)

In the book, chapter three, almost all phase noise results like equation (49) (page 57) contains 1/(Δω)2 term. This term, in Abidi’s book, is obtained from multiplying noise current and lossy tank impedance. The latter item contains 1/(Δω)2 term.

However, in some other papers, it is stated that 1/(Δω)2 term comes from integration over time operation. Since a oscillator is a system with memory, any perturbation could either be rejected as AM noise or get memorized as PM noise. Thus, any noise source would get a noise power transfer function as 1/s2. When show up in the phase noise results, it will have a term as 1/(Δω)2.

Why Abidi’s derivation does not assume this integration property, and get the same form of results?

Thanks,
Neo

Title: Re: Phase noise derivation in Book “High-Purity Os
Post by neoflash on Jan 1^st, 2007, 1:04am

one type is the post is that we should scale noise current by "lossless tank" impedance.