METHOD FOR DETERMINING EXCESS NOISE PARAMETERS Russian patent published in 2020 - IPC G01R29/26 

FIELD: measurement.

SUBSTANCE: invention relates to measurement equipment and can be used for determination of parameters of excess noise of electronic equipment products at control of their quality and prediction of failures, as well as in scientific research. Method for determining excess noise parameters comprises determining said parameters using a plurality of frequencies, and the analysed noise signal is amplified and passed through filters tuned in certain manner to these frequencies. Effective passages of filters are proportional to selected frequencies, and these frequencies themselves are located in certain positions within their respective pass bands. Further, average power of noise voltage at filter outputs is measured by means of its quadratic detection and averaging (integration during any fixed time interval) and, based on known dependence of spectral density of excess noise power on frequency, using the determined computing operations results of these measurements to determine parameters of this relationship - frequency index γ, proportionality coefficient B, as well as the power spectral density itself, which is determined by formula

at any frequency, where S_exc is power spectral density of excess noise; B - proportionality factor; ω is circular frequency; γ is frequency index, wherein three frequencies are selected ω₁, ω₂, ω₃, which are numbered for definiteness in such a way that relation ω₁ > ω₂ > ω₃. Resonance frequencies of band-pass filters ω₀₁ , ω₀₂ and ω₀₃ are equal to selected frequencies ω₁, ω₂ and ω₃. Each filter having the same structure of connections of its elements is made in the form of a linear passive or active three-terminal network with a voltage transfer function given by the mathematical expression disclosed in the description of the invention. At that, filters are tuned to selected resonant frequencies ω₀₁, ω₀₂ and ω₀₃ so that their Q-factors q and transmission coefficients K₀ at their resonant frequencies remain the same. Average noise power P₁, P₂ and P₃ at the outputs of filters 1, 2 and 3 are measured. Based on the results of these measurements, determining one of the excess noise parameters - the frequency index γ, with at given frequency ratio settings ω₀₁, ω₀₂ and ω₀₃. Then calculate the proportionality factor B, and the power spectral density of excess noise S_exc.

EFFECT: method enables to determine parameters of excess noise in conditions without significant prevalence thereof over white noise, using simple in design and easy-to-configure filters with not necessarily very narrow effective bandwidths and with resonance frequencies located in not necessarily too deep low-frequency region, and thereby enables to significantly reduce the time of measurement operations.

1 cl, 3 dwg