作者机构:[1]Department of Electronic Engineering, Tsinghua University, Beijing 100084, China, [2]Department of Communication Engineering, Xiamen University, Xiamen 361005, China
相关基金:Supported by the National Natural Science Foundation of China (No. 90607009), the National High-Tech Research and Development (863) Program of China (No. 2008AA01Z107), and the National Key Basic Research and Development (973) Program of China (No. 2007CB310701 )