A.V. Brovko - Dr.Sc. (Phys.-Math.), Associate Professor, Department of Applied Information Technologies, Yuri Gagarin State Technical University of Saratov (SSTU) E-mail: brovkoav@gmail.com R.S. Pakharev - Post-graduate Student, Department of Applied Information Technologies, Yuri Gagarin State Technical University of Saratov (SSTU) E-mail: ruslanpaharev@rambler.ru

The problem of detection of heterogeneity in the dielectric materials located in the closed waveguide measuring systems is considered in the paper.The solution of this problem is of great practical interest as the received decision can be applied in many field of science and equipment where monitoring of internal structure of materials is required.Use of the received de-cision is of special interest for monitoring of internal structure of the material subjected to the microwave oven to processing. For a solution the method based on use of mathematical apparatus of the artificial neural networks (ANN) is offered.The essence of a method consists in the following: creating the model of the measuring system comprising the studied sample; modeling of this measuring system; further the mathematical model of measuring system is realized in the form of ANN which is trained with use of the results received as a result of modeling; after training of ANN it is capable to detect heterogeneity in a dielectric sample. During modeling of measuring system, the training sets (couple of input and output data sets) are generated as random data set follows then every time is calculated a matrix of dispersion of turnstile connection.After completion of modeling we receive a numerical data set which will be used for training of a neural network. After the neural network is rather trained, it can be used for detection of heterogeneity in a dielectric sample by results of measurements of coefficients of reflection and passing of the electromagnetic field in ports of measuring system. To illustrate the performance of the proposed method, the paper presents numerical results of the detection of heterogeneity of various geometrical form in a dielectric sample are given in article.

 

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