1. School of Information and Communications Engineering, Xi'an Jiaotong University,Xi'an,Shaanxi,China
2. Academy of Mathematics and Systems Science, Chinese Academy of Sciences,Beijing,China
3. Shanghai Huawei Technologies Co. Ltd.,Wireless Network RAN Research Department,Shanghai,China
4. School of Electrical Engineering and Computer Science, Peking University,Beijing,China
5. School of Electrical and Information Engineering, The University of Sydney,Sydney,NSW,Australia,2006