State Primary Standard of the Power Spectral Density Unit of Noise Radio Emission in the Frequency Range from 0.002 to 178.3 GHz Get 21-2021

In 2021, the State primary standard of the power spectral density unit of noise radio emission in the frequency range of 0.002 to 178.3 GHz GET 21-2021 was approved. Low-temperature noise generators were included in GET 21-2021 as primary standard measures. The designed and manufactured primary standard measures were studied, namely two coaxial low-temperature noise generators in the frequency ranges of 0.002-4.0 GHz and 4.0-12.05 GHz and three waveguide low-temperature noise generators in the frequency ranges of 12.05-17.44 GHz, 17.44-25.86 GHz, and 25.86-37.5 GHz. Equivalent noise temperatures of primary standard measures were investigated and calculated. The reproducible value of the equivalent noise temperature for coaxial low-temperature noise generators was 77.5-84.82 K, and 78.4-80.53 K for waveguide low-temperature noise generators. Comparators, namely noise signal receivers covering five frequency ranges (two coaxial paths: 0.002-4.0 GHz and 4.0-12.05 GHz; three waveguide lines: 12.5-17.44 GHz; 17.44-25.86 GHz, and 25.86-37.5 GHz) were developed and manufactured. The dynamic range of measurements was increased, and the error in transmitting a unit of the power spectral density of noise radio emission was reduced. The total error in reproducing the power spectral density unit of noise radio emission was 0.24-0.30 K, the expanded uncertainty of transferring the power spectral density unit of noise radio emission to secondary standards and working standards of the first echelon was 0.4-0.8 K, and the measurement error of the power spectral density of noise radio emission decreased by a factor of 1.5. The uncertainties in the transfer of a unit of the power spectral density of noise radio emission from primary standard measures to secondary standards and working standards of the first echelon were comparatively analyzed.The results of this work are applicable in the radio industry for noise parameter measurements. The sensitivity values of instruments and devices whose operation depends on the level of noise electromagnetic oscillations, such as measuring noise generators, are controlled by measures of the power spectral density of noise radio emission.