[1] Air Force Early Warning Acad, Dept Basics, Wuhan 430019, Hubei, Peoples R China
[2] Air Force Early Warning Acad, Huangpi NCO Sch, Dept Basics, Wuhan 430345, Hubei, Peoples R China
[3] Huangshan Univ, Dept Phys, Huangshan 245041, Peoples R China
[4] Huazhong Univ Sci & Technol, Dept Phys, Wuhan 430074, Hubei, Peoples R China