作者机构:Key Laboratory of Optical Communications and Lightwave Technologies, Beijing University of Posts and Telecommunications, Beijing 100876, China
相关基金:Acknowledgements This work was supported by the National Basic Research Program of China (2007CB310705), the Hi-Tech Research and Development Program of China (2007AA01Z255), the National Natural Science Foundation of China (60711140087), PCSIRT (IRT0609), and ISTCP (2006DFA 11040) of China.