A.V. Denisov - Ph. D. (Phys.-Math.), Associate Professor, Department «Radioengineering and telecommunications», St. Petersburg State Polytechnical University. E-mail: A.V.Denisov@inbox.ru M.A. Belyansky - Post-graduate Student, Deputy Head of Department, JSC «SRC «Leninetz Plant» (SPb). E-mail: maxim_belyansky@mail.ru