R.K. Yafarov - Dr. Sc. (Eng.), Professor, Saratov branch of Kotel\'nikov IRE of RAS E-mail: pirpc@yandex.ru S.Yu. Suzdaltsev - Ph. D. (Eng.), Saratov branch of Kotel\'nikov IRE of RAS E-mail: suzdaltsevsy@rambler.ru V.Ya. Shanygin - Ph. D. (Eng.), Research Scientist, Saratov branch of Kotel\'nikov IRE of RAS E-mail: vitairerun@mail.ru