Developing algorithm for building regression polynomial to approximate nonlinear curve of transmission function of viba power amplifier using multi-purpose optimization method
Keywords:
Complex nonlinearity, Power amplifier, Characteristic approximation, Intermodulation distortionAbstract
This paper presents the algorithm for building regression polynomial to approximate the nonlinear curve of the transmission function of viba power amplifier using a multi-purpose optimization method based on the experimental data for amplitude characteristics (AX) and phase (FАХ) of the nonlinear microwave power amplifier. The multi-purpose optimization method is solved by including the following criteria: (1) Sum of squares of error at experimental points; (2) The maximum deviation (h) of the regression characteristic from the experimental line; (3) The total area (S) is biased by the regression and experimental characteristics. These purposes are almost opposite to each other, achieving one purpose will lose another. The author uses the Pareto set and the conversation method to find a better solution than the conventional polynomial regression method. The found approximation regression polynomial is used to calculate the power of the useful and intermodulation components. The author has developed a software module in the MATLAB environment to maximize the automation of the steps.
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