1. State Key Laboratory of Optical Fiber and Cable Manufacture Technology, China Telecom Research Institute, Beijing 100876, China
2. WDM System Design Department of Wireline Product R&D Institute, ZTE Corporation, Wuhan 430073, China
3. State Key Laboratory of Optical Fiber and Cable Manufacture Technology, Yangtze Optical Fiber and Cable Joint Stock Limited Company, Wuhan 430073, China