1. School of Electrical and Computer Engineering, State University of Campinas, Campinas, Brazil
2. National Institute of Information and Communications Technology (NICT), Tokyo, Japan
3. High Capacity Optical Transmission Laboratory, Electro-Optical Communications Group, Eindhoven University of Technology, Eindhoven, The Netherlands
4. Nokia Bell Labs, Holmdel, NJ, USA
5. University of Stuttgart, Stuttgart, Germany