Competing interests
The authors declare that they have no competing interests.
Acknowledgements
This study was supported in part by research funds from Chosun University,2012.
Author details
1 Department of Electronic Engineering, Chosun University, Gwang ju 501-759,South Korea.
2 School of Computer Engineering, Chosun University, Gwang ju 501-759, South Korea.
3 Optical Communications Research Group, Faculty of Engineering and Environment, Northumbria University, Newcastle NE1 8ST,UK.
4 Advanced Photonics Research Institute, Gwangju Institute of Science and Technology, Gwangju 500-712, South Korea.
5 Max Speed Media and Technology, Hanoi, Vietnam. Received: 19 April 2013 Accepted: 13 October 2013 Published: 28 October 2013