1. Departamento de Engenharia de Telecomunicacções e Controle, Escola Politécnica na Universidade de São Paulo, São Paulo 05508-010, SP, Brazil
2. Facultad de Ingeniería, Universidad de Talca, Curico 3340000, Maule, Chile
3. Pontifical Catholic University of Campinas (PUC-Campinas), Center for Exact, Environmental and Technological Sciences (CEATEC), Postgraduate Program in Telecommunication Networks Management, Campinas 13086-900, SP, Brazil
4. Engineering and Technology Institute Groningen, Faculty of Science and Engineering, Rijksuniversiteit Groningen, 9747 AG Groningen, The Netherlands