1. State Key Laboratory of Media Convergence and Communication, School of Information and Communication, Communication University of China, Beijing 100024, China
2. Beijing Laboratory of Advanced Information Network, Beijing Key Laboratory of Network System Architecture and Convergence, Beijing University of Posts and Telecommunications, Beijing 100876, China
3. State Key Lab of Processors, Institute of Computing Technology, Chinese Academy of Sciences, Beijing, 100190, China, with the Beijing Key Laboratory of Mobile Computing and Pervasive Device, Beijing, 100080, China, and also with University of Chinese Academy of Sciences, Beijing 100049, China