Application of Simulation Modeling to Determine the Parameters of Electrical Signals by Using a Quadrature Demodulator

Currently, the complexity of electronic devices and the components that make up them is constantly growing. As a result the complexity of analyzing possible faults, the difficulty of identifying operational deficiencies and analyzing emerging errors is growing. In the educational process, these factors play a significant role and limit physical and mathematical modeling. One possible solution to this problem is the use of simulation modeling. One of the convenient tools for constructing circuit simulation models is the Simulink software package. This paper explores the application of Simulink in constructing a simulation model for a quadrature demodulator. This device is widely used in measurement technology and is used to perform amplitude, phase spectrum and frequency measurements. The features of the implementation of modifications of this method to improve the accuracy of measurement are considered. The results are obtained for the case of sinusoidal and polyharmonic signals, as well as signals distorted by noise, which allow us to evaluate the effectiveness of the proposed techniques. The impact of the non-linearity of the analog-to-digital converter (ADC) on the measurement error of the parameters discussed above is investigated. Different types of nonlinearities are considered: pseudorandom, “worst case” representation, sinusoidal function, power polynomial function, Chebyshev polynomials of different orders. The issues of constructing the proposed model and its application in the educational process are considered.