[1] [1] FENG Ruo. Principles and Design of Ultrasonic Diagnostic Instrument [M]. Beijing: China Medical Science and Technology Press, 1993: 339-356, 438-496.

[2] [2] Cysewska-Sobusiak A, Sowier A, Skrzywanek P. Utilization of Miniprobes in Modern Endoscopic Ultrasonography [J]. IEEE Sensors Journal(S1530-437X), 2006, 6(5): 1323-1330.

[3] [3] JING Zhendong, LI Zhaoshen. Digestive Endoscopic Ultrasonography [M]. Beijing: Science Press, 2006: 60-68.

[4] [4] CHEN Xiaodong, LI Ming, YU Feng, et al. Technology of digital endoscopic ultrasonic Imaging [J]. Chinese Joural. Lasers, 2009, 36(10): 2557-2560.

[5] [5] Dos Santos, Mário Joao Simoes Ferreira. FPGA-based control system of an ultrasonic phased array [J]. Mechanical Engineering(S0039-2480), 2011, 57(2): 135-141.

[6] [6] Selbie R D, Hutchison J M S, Mallard J R. The Aberdeen phased array: a real-time ultrasonic scanner with dynamic focus [J]. Medical & Biological Engineering & Computing(S0140-0118), 1980, 18(3): 335-343.

[7] [7] ZHAN Xianglin, CHEN Shili, ZHANG Yu, et al. Optimum design of ultrasonic phased array in flaw detection of pipeline [J]. Chinese J. Scientific Instrument, 2006, 27(Suppl 6): 1581-1582.

[8] [8] QI Yan, TAN Guanzhen, FAN Bishuang. Design of FPGA-based digital beamformer in medical ultrasound imaging [J]. Computer Measurement & Control, 2010, 18(4): 896-899.

[9] [9] ZHANG Xiaohui, ZHANG Kai, QIU Wenjing. Design of digital beamforming in diagnostic ultrasound [J]. Progress in Modern Biomedicine, 2009, 9(1): 128-130.

[10] [10] WEN Shijie, WANG Xiaohua, CHEN Xiaodong, et al. Digital quardrature demodulator for detecting ultrasonic signal based on FPGA [J]. Optoelectronics·Laser, 2008, 19(10): 1324-1327.