1. Department of Electrical Engineering, Federal University of Juiz de Fora, Juiz de Fora 36036-900, Brazil
2. Department of Electronics Engineering, Federal Center for Technological Education of Rio de Janeiro, Rio de Janeiro 20271-110, Brazil
3. Department of Electrical and Computer Engineering, Western University, London, ON N6A 5B7, Canada
4. CEB Lajeado, Brasilia 71215-902, Brazil