A.V. Bogoslovsky - Dr. Sc. (Eng.), Professor, Department of Higher Mathematics, Tambov state technical University. E-mail: p-digim@mail.ru I.V. Zhigulina - Ph. D. (Eng.), Associate Professor, Department of Applied Mathematics and Mechanics, Tambov state technical University. E-mail: irazhigulina@gmail.com I.S. Maslov - Post-graduate Student, Department of Radio Engineering, Tambov state technical University. E-mail: klewer_tambov@mail.ru