Calibration Method of Carrier-to-Noise Ratio in High-precision Fixed-Signal-Variable-Noise Mode

Abstract

The invention provides a method for calibrating a carrier-to-noise ratio of a high-precision fixed-signal and noise-reducing mode, and the method specifically comprises the following steps of constructing a combiner system of a pure signal and noise; determining an expected pure signal power Ps and an expected carrier-to-noise ratio CN0 of the pure signal power generated by a signal generator in the combiner system, determining the attenuation amount La of an attenuator, determining the power spectral density of the noise generated by the noise generator, setting the pure signal power generated by the signal generator in the combiner system to be the same as the above determined value; and setting the attenuation amount of the attenuator as La such that the noise power spectral density generated by the noise generator is the signal-to-noise ratio CN0' of the combiner system outputting the noisy signal, that is, the carrier-to-noise ratio calibration is completed. The method provided bythe invention considers the influence of noise figures of the attenuator, the combiner and the cable in the combiner system on the noise power spectral density, greatly reduces errors of the carrier-to-noise ratio calibration, improves the accuracy of the carrier-to-noise ratio calibration, and solves the problems in the prior art.

Description

technical field [0001] The invention belongs to the technical fields of electronic information engineering and aerospace engineering, and relates to a carrier-to-noise ratio calibration method in a high-precision signal-constant-variable-noise mode. Background technique [0002] In the fields of electronic information engineering and aerospace engineering, it usually involves the analysis, processing and testing of analog signals with pre-calibrated carrier-to-noise ratios, which requires the use of carrier-to-noise ratio calibration methods to design and generate signals with definite carrier-to-noise ratios. To achieve carrier-to-noise ratio calibration, a combination system of pure signal and noise needs to be built in advance. The composition of the combining system generally includes a signal generator, a noise generator, a combiner, an attenuator, and a coaxial cable. The signal flow direction in the system is: use the signal generator to generate a pure signal, and us...

AI Technical Summary

Problems solved by technology

This carrier-to-noise ratio calibration method is relatively simple to calculate, but it ignores the influence of the noise figure of the attenuator, combiner, and cable in the combiner system on the noise power spectral density, which makes the expected pure signal power smaller In some cases, the calibrated carrier-to-noise ratio has a large error compared with the real carrier-to-noise ratio of the noisy signal, which has a significant impact on practical engineering applications.

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