抗混叠滤波器在医学成像系统中的应用研究和设计

Application research and design of anti-aliasing filter in medical imaging system

滤波电路设计是医学成像系统信号处理的关键环节。通过分析医学成像系统原理和共性电路构成,研究前级放大和后级模数转换对滤波器设计指标的影响,以超声成像系统滤波器设计为例,采用归一化查表法设计5阶切比雪夫滤波器,分别通过MATLAB软件仿真和网络分析仪对滤波器进行测试。结果表明所设计滤波器参数和指标均符合设计要求。

The design of filter circuit is the key link of signal processing in medical imaging system. The effects of preamplifier and analog- to- digital converter on filter parameters were studied by analyzing the principle of medical imaging system and the structure of common circuit. The filter design of ultrasonic imaging system was taken as example, five-step Chebyshev filter was designed by using normalization look- up table method. MATLAB software simulation and network analyzer were used to test the filter. The results showed that the parameters and indexes of filter met the design requirement.