中文摘要：

为解决印制电路板（PCB）在工作中出现的电磁兼容（EMC）问题，对采集单元PCB及屏蔽盒的EMC性能进行研究。将PCB根据功能实现分割，加粗电源线和地线的宽度，选用贴片元件，减小相邻传输线间的平行长度：同时对屏蔽盒整体采用插接结构，在可拆卸面板的机箱内设计并布置防静电金属弹片，可增加面板与机箱其他位置的电导率、减少静电电荷积累，以提高设备抗扰度、减少辐射骚扰。最后基于HFSS软件，对PCB和屏蔽盒进行建模仿真，通过结果分析可得，优化后的PCB电磁场分布更均匀，屏蔽盒的屏蔽效果显著，EMC特性得到很大程度的提高，证明对PCB和屏蔽盒的设计满足测试要求。

英文摘要：

In order to solve the problem of electromagnetic compatibility （EMC） in printed circuit board （PCB）, the method of theoretical analysis and simulation modeling is used to study the EMC of the collection unit PCB and the shielding case.To split PCB according to the function, bolding the width of the power and the ground cord, choosing surface mount technology components as far as possible and reducing the parallel length between adjacent transmis- sion lines.At the same time, a plug structure of shielding case is designed ,putting antistatic metal shrapnel inside the shielding case to improve the immunity, reducing radiation harassment.The simulation models of PCB and shielding case are built by HFSS.Through the analysis of the results, for the improved PCB, the electromagnetic field distribu- tion is more homogeneous, the effect of shielding case is remarkable, the EMC is improved greatly, and the design of the PCB and the shielding case can pass the test.