1. Electrical Engineering Department, School of Engineering, Persian Gulf University, P.O. Box 75169, Bushehr 75169-13817, Iran e-mail:
2. Electronic and Electrical Engineering Department, Shiraz University of Technology, P.O. Box 71555-313 Shiraz 71557-13876, Iran e-mail:
3. R&D Unit CIDMA, Department of Mathematics, Center for Research and Development in Mathematics and Applications, University of Aveiro, Aveiro 3810-193, Portugal e-mail: