S. A. Kapustin – Post-graduate Student,

Department of Physics and Technology of Optical Communication,

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

E-mail: physics@nntu.ru

A. V. Nazarov – Ph.D. (Eng.), Associate Professor,

Branch FSUE RFNC VNIIEF «Measuring System Research Institute n.a. Yu.Ye. Sedakov» (Nizhny Novgorod)

E-mail: aNazarov@niiis.nnov.ru

S. B. Raevskij – Dr.Sc. (Eng.), Professor,

Department of Physics and Technology of Optical Communication,

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