1. Center of Aerocraft TT&C and Communication and School of Microelectronics and Communication Engineering, Chongqing University, Chongqing, China
2. School of Microelectronics and Communication Engineering, Chongqing University, Chongqing, China
3. School of Information and Communications Engineering, Xi’an Jiaotong University, Xi’an, China
4. Department of Communications Engineering, Tohoku University, Sendai, Japan