I. P. Kovalyov – Ph.D. (Eng.), Associate Professor,

Department of Electronics and Computer Networks,

Nizhny Novgorod State Technical University n.a. R.E. Alekseev

E-mail: physics@nntu.ru

N. I. Kuzikova – Ph.D. (Eng.), Associate Professor,

Department of Physics and Technology of Optical Communication,

Nizhny Novgorod State Technical University n.a. R.E. Alekseev E-mail: nata.kuz68@mail.ru