1. Xi’an Jiaotong University, School of Information and Communications Engineering, Xi’an, China and University of Alberta, Department of Physics, Edmonton, Alberta, Canada.
2. Xi’an Jiaotong University, School of Information and Communications Engineering, Xi’an, China.
3. Xinjiang Oilfield Company Ltd., Institute of Geophysics, Urumqi, China.
4. University of Alberta, Department of Physics, Edmonton, Alberta, Canada.
5. Xi’an Jiaotong University, School of Information and Communications Engineering, Xi’an, China. (corresponding author)