（毕业设计论文）《1GHz-10GHz同轴电缆及其连接器屏蔽效能的混波室法试验研究》.doc

毕业设计（论文）报告 ????????????????机械工程学院???????????????????????机械设计制造及其自动化???????? ? 设计（论文）题目 ???1GHz~10GHz同轴电缆 ????????????????????????????????????????????????????及其连接器屏蔽效能的混波室法试验研究 ??????????????? 学 生 姓 名 ???? 起 止 日 期 ?????????? 设 计 地 点 东南大学电磁兼容研究室??????? ? 指 导 教 师 ??????????? ?? ??????? 摘要 电子设备的连接电缆是一个极其危险的电磁能量泄漏窗口，而目前尚无精确的计算电缆的屏蔽效能的公式，屏蔽电缆的屏蔽效能一般都是由实际测量确定。电缆的屏蔽效能的测量方法有很多种。混响室是利用屏蔽室内的机械搅拌器，连续改变内部的电磁场结构，使得屏蔽室内任意位置的能量密度的相位、幅度、极化均按某一固定的统计分布规律随机变化。电缆在混响室内处于均匀的电磁场环境中，而且被测电缆不需要特殊的固定装置。由于屏蔽室是高值的谐振腔，因此可用相对较小的功率得到高的场强。而且因屏蔽室最低谐振频率使混响室低频受到限制外，高频没有限制，因此动态范围大。因为混响室可以产生高的场强，而且场分布均匀，因此可用混响室法测量屏蔽效能好的电缆，这种方法尤其适用于以上频段的使用。 关键词：混响室 同轴电缆 连接器 屏蔽效能 ABSTRACT Electronic equipment connecting cable is a very dangerous leakage of electromagnetic energy window, at present there is no accurate calculation formula of the cable shielding effectiveness, Shielded cables shielding effectiveness are generally determined by the actual measurement. There are many method to measure Cable shielding effectiveness. There is a stirrer in the reverberation chamber which is used to change electromagnetic field continuously. It makes that inside a reverberation chamber the exciting field statistically comes from any possible direction, with any possible polarization and phase is stochastic. Inside a reverberation chamber the cable is excited by a field statistically uniform, moreover, no test fixture is required to mount the cable under test. Because the reverberation chamber has high value Q, it can get a high field strength from low power , the reverberation chamber has low-frequency limits by its minimum resonant frequency, and has no restrictions on high-frequency ,so it has a large dynamic range. Because of the reverberation chamber can produce high-field strength, and uniform distribution, so available reverberation chamber measuring cable which has high shielding effectiveness, this method is especially applicable to the use of fre