中文摘要：

研究了静电执行的电容式并联毫米波MEMS开关的S参数在开关过程中的瞬态变化。以一个电容式并联毫米波MEMS开关为实例，采用已有的开关一维力学动态模型，建立了开关过程中开关梁与介质层之间的间隙与时间的关系；通过HFSS电磁仿真软件，得到开关S参数在开关过程中的瞬态变化。结果显示，在开关下拉过程中（用时约9．4us），插入损耗S21先缓慢减小（从Up态稳定值-0．20dB缓慢减小到-1．02dB需时9．11us，占开关下拉时间的97％），但在下拉时间末段迅速减小；在开关释放过程中（用时约20us），S21在初段就迅速增大（从Down态的稳定值-20．1dB迅速增加到-1．16dB只需1．09us，占开关释放时间的5．5％）。结果表明，开关从导通信号到阻隔信号的转换时间约为开关的下拉时间；开关从阻隔信号到导通信号的转换时间要比开关的释放时间小一个数量级。

英文摘要：

The transient S-parameters of a capacitive shunt and electrostatically actuated millimetrewave switch were researched. The transient change of these parameters during switching in the gap between switch beam and dielectric layer was derived by a one-dimension mechanical dynamic model from a published paper. Then, the transient change in the gap was used for simulating the transient S-parameters during switching in HFSS software. Finally, this method was applied to a specific switch. Obtained results show that the inserting loss S21 decreases slowly until the end of the pull-in process （from steady value -0.20 dB in Up-state to -1.02 dB over 9.11 us, 97% of the pull-in time）, and it increases quickly to nearly the ultimate value at the beginning of the release process （from steady value -20.1 dB in down-state to -1.16 dB over 1.09 us, 5.5% of the release time）. The transition time from a passing RF signal to a blocking RF signal is about the time of pull-in, and the transition time from a blocking RF signal to a passing RF signal is one order of magnitude less than the releasing time.