1. Department of Physics, Faculty of Science; King Abdulaziz University; 21589 Jeddah Saudi Arabia
2. Department of Mathematics, Faculty of Science; King Abdulaziz University; 21589 Jeddah Saudi Arabia
3. Department of Polymer Engineering; University of Chemical Technology and Metallurgy; 1756 Sofia Bulgaria
4. Department of Wireless Communications and Broadcasting; Graduate School of Telecommunications; 1700 Sofia Bulgaria
5. Department of Communication and Computer Engineering, Faculty of Engineering; Neofit Rilski South-West University of Blagoevgrad; 2700 Blagoevgrad Bulgaria