1. Information and Communication Branch, Jiangxi Electric Power Corporation, State Grid, Nanchang, China
2. Institute of Optoelectronics and Optical Communication Technologies, Jiangsu University, Zhenjiang, China
3. Key Laboratory of Optoelectronic and Telecommunication of Jiangxi Province, School of Physics and Communication Electronics, Jiangxi Normal University, Nanchang, P.R. China