1. Department of Mobile Communications and Terminal Research, China Telecom Research Institute, Guangzhou, China
2. Shenzhen Institute for Advanced Study, the National Key Laboratory of Science and Technology on Communications, and the Center for Intelligent Networking and Communications, University of Electronic Science and Technology of China, Chengdu, China
3. Center for Intelligent Networking and Communications, University of Electronic Science and Technology of China, Chengdu, China
4. National Key Laboratory of Science and Technology on Communications and the Center for Intelligent Networking and Communications, University of Electronic Science and Technology of China, Chengdu, China
5. China Telecom Research Institute, Guangzhou, China