1. Hayakawa Institute of Seismo Electromagnetics Co. Ltd. (Hi‐SEM) University of Electro‐Communications (UEC) Chofu Japan
2. Advanced Wireless and Communications Research Center (AWCC) UEC Chofu Japan
3. A. Ya. Usikov Institute for Radio‐Physics and Electronics National Academy of Sciences of the Ukraine Kharkov Ukraine
4. Department of Mathematics and Computer Sciences Saint‐Petersburg State University Saint‐Petersburg Russia
5. Department of Mathematics and Informatics V.N. Karazin Kharkov State University Kharkov Ukraine