内部窗口结构对开孔矩形腔体近场屏蔽效能的影响

针对开孔屏蔽腔体内置窗口的结构特点,采用扩展的传输线方法理论,建立了电偶极子天线照射下计算近场屏蔽效能的等效电路模型,推导了近似计算解析式,并计算分析了内部窗口结构对开孔腔体近场屏蔽效能的影响.结果表明:含内置窗口结构腔体的近场电场屏蔽效能小于远场屏蔽效能,腔体屏蔽效能随窗口宽度的减小而增大,电感窗口使得腔体谐振频率向上偏移,电容窗口使其谐振频率向下偏移.分析结果与CST仿真结果进行了对比,证实本文采用的等效电路方法是有效的.

Influence of inner windows on near-field shielding effectiveness of rectangular cavity with apertures

Influence of the inner windows on the shielding effectiveness of a cavity with apertures is investigated by using the adjusted transmission line method (TLM). Electric shielding effectiveness is calculated as a function of the opening width of metal windows. It is shown that the electric near-field shielding effectiveness of a cavity with inner windows and apertures is far inferior to that of far-field. Results also show that the near-filed shielding effectiveness increases with the decrease of the opening width of the inner window, and the capacitive windows may lower the resonance frequency while the inductive windows may enhance. Results of the adjusted TLM are in good agreement with the CST simulation results.