1. Department of Electrical Engineering, School of Energy Systems, Lappeenranta-Lahti University of Technology (LUT), Lappeenranta, Finland
2. Department of Electrical Engineering, Federal University of Juiz de Fora University (UFJF), Juiz de Fora, Brazil
3. Tropico Systems and Telecommunications, Campinas, Brazil
4. Research and Development Center in Telecommunications (CPqD), Campinas, Brazil
5. Department of Computer Science, Universidade Federal de Lavras (UFLA), Lavras, Brazil