A new test method on the conversion loss of mixer

In order to reduce the influence of frequency conversion loss test error on the spectrum measurement system, based on the analysis and comparison of the existing test methods and the source of the error, a new test method with higher testing precision is proposed by introducing a matching network model based on the analysis and comparison of the existing test methods and the source of the error. By using linear polynomial fitting, Gaussian fitting and Fourier fitting to the mesured data, the appropriate data fitting method can be selected according to the discriminant approach, which can reduce the fitting error of frequency conversion loss in the system and improve the measurement precision of the spectrum measurement system. This method is suitable for the precise testing and auotomatic matching of frequency conversion loss.