Yuliang Liu1, Guohua Liu2, Quan Zhang3. 1. College of Electronic Information and Automation, Tianjin University of Science and Technology, Tianjin, China. 2. Key Laboratory of Optoelectronic Sensor and Sensing Network Technology, College of Electronic Information and Optical Engineering, Nankai University, Tianjin 300350, China. 3. Key Laboratory of Optoelectronic Sensor and Sensing Network Technology, College of Electronic Information and Optical Engineering, Nankai University, Tianjin 300350, China; College of Electronic Information and Automation, Tianjin University of Science and Technology, Tianjin, China. Electronic address: zqaccepted@126.com.