Zhou Sheng, Wang Xiaochun, Yang Jun, Wang Yanqun
Biomedical Engineering Institute, Chinese Academy of Medical Sciences, Tianjin 300192.
Zhongguo Yi Liao Qi Xie Za Zhi. 2011 Nov;35(6):409-13.
This paper combined the coded excitation with the technique of ophthalmic high-frequency ultrasonic imaging, and raised a new high-velocity data detection and signal processing method. 16 bit Golay complementarity sequences were produced by FPGA, which excited the probe to produce ultrasonic waves. Data detection circuit achieved the digitalized of the 15 MHz high-frequency ultrasonic echo signals in real time. Sampling rate was 120MHz, and sampling bit was 14 bit. Decoded compression arithmetic was realized by FPGA in real time, in which A code compression was alternated with B code compression. The return echo was correlated with the corresponding decode filter A and filter B respectively, and then the echo was delayed and summed to complete the decoding process. The experiment indicated that coded excitation can effectively increase the range of mainlobe and decrease the range of sidelobe. This technique can effectively raise the signal-to-noise ratio, and has significant research value in advancing the ophthalmic ultrasonic image quality and raising the safety of the equipment.
本文将编码激励与眼科高频超声成像技术相结合，提出了一种新的高速数据检测与信号处理方法。由现场可编程门阵列（FPGA）产生16位戈莱互补序列，激励探头产生超声波。数据检测电路实现了15MHz高频超声回波信号的实时数字化。采样率为120MHz，采样位数为14位。由FPGA实时实现解码压缩算法，其中A码压缩与B码压缩交替进行。回波分别与相应的解码滤波器A和滤波器B相关，然后对回波进行延迟和求和以完成解码过程。实验表明，编码激励可有效增加主瓣范围并减小旁瓣范围。该技术可有效提高信噪比，在提升眼科超声图像质量和提高设备安全性方面具有重要的研究价值。
