1. Telecomunicações e Informática, Universidade de Aveiro,Instituto de Telecomunicações and Departamento de Electrónica,Aveiro,Portugal,3810-193
2. Northumbria University,Optical Communications Research Group, Faculty of Engineering and Environment,Newcastle upon Tyne,U.K.,NE1 8ST
3. Czech Technical University in Prague,Faculty of Electrical Engineering,Department of Electromagnetic Field,Prague,Czech Republic,16627