A Novel Noise Analysis Method in Microwave Oscillators Based on Harmonic Balance

Abstract

In this article a general noise analysis for microwave oscillators based on harmonic balance method is presented. First order differentials are used in matrix forn and the noise spectra about each harmonic is obtained The method is general and independent of circuit topology and noise sources spectral distribution .Defining a noise correlation matrix all noise sources effect can be considered in the spectral computation of the output signal.

The Harmonic-Balance Analysis of the Noise of Nonlinear Microwave Circuits

“…By the presence of noise, and since the noise sources are small compared to the harmonic voltages, one can rewrite (5) as [5]: V I(Vm,k + AVmk (t))X where AVm k (t) a k (t) represent, respectively, the amplitude and phase fluctuations due to noise. Inserting (6) into the HB characteristics equation (2), and expanding with the first-order derivatives, then by some manipulation, one can obtain: VJ(V|)-V J(w))]Av(w) + jWJ()9(w) =n(w) (7) where, J(|V|) = OF / O|V,, J(w) = OF / co| =00 Equation (7) describes the transfer properties of a small signal in the nonlinear circuit under large signal steady operation.…”

“…In the last decade, many evaluation methods [1][2][3][4][5] [1][2][3][4][5] have been taken into account for nonlinear microwave noise. Although the noise spectral analysis by conversion matrices is convenient and accurate since the cross correlation of noise sources is well considered, it is limited to characterize the effect of frequency modulation near the carrier.…”