A.F. Nadeev - Dr.Sc. (Phys.-Math.), Professor, Director, Institute of Radioelectronics and Telecommunications, Kazan National Research Technical University named after A.N. Tupolev (KNRTU-KAI). E-mail: afnadeev@kai.ru
I.A. Podkurkov - Post-graduate Student, Kazan National Research Technical University named after A.N. Tupolev (KNRTU-KAI). E-mail: podkiva@mail.ru