一种抑制微放电的宽带大功率定向耦合器设计

Design of a broadband high power directional coupler for suppression of multipactor

在卫星有效载荷系统中,3 dB定向耦合器作为微波工程关键器件已得到广泛应用,而此类器件在太空真空环境中,常因真空环境下大功率工况引发的微放电效应形成谐振放电现象,影响耦合器性能与寿命,对于卫星系统日益增多的小型化及大功率需求,在器件设计时应充分考虑微放电效应并兼顾小型化要求,采用有效抑制手段以确保器件在轨稳定可靠。通过分析定向耦合器工作原理与不同结构耦合器之间的差异,阐述了真空环境下的微放电效应产生机理,针对性地采取基于奇偶模分析法的耦合线结构耦合器设计方法,选用高导热材料Rogers TC350+作为耦合器介质,利用软基板多层混压方式进行产品加工,通过仿真试验与真空环境实测,表明此类设计既具有体积小、重量轻的特点,又可有效抑制器件微放电效应,确保了耦合器的工作性能,满足卫星系统使用工况。

In the satellite payload system,3 dB directional coupler has been widely used as a key device in microwave engineering.In the spatial vacuum environment,resonant discharge is often caused by micro discharge effect which due to high-power working conditions,which would affect the performance and service life of the directional coupler.In the device design,the micro discharge effect should be fully considered and effective suppression measures should be adopted to ensure the stability and reliability of the device on orbit.By analyzing the working principle of directional coupler and the differences between couplers with different structures,and the mechanism of micro discharge effect in vacuum environment is described,the design method of coupling line structure coupler which based on parity model analysis is adopted,and the high thermal conductivity material which called Rogers TC350+is selected as the coupler medium.The product is processed by multi-layer mixing of soft substrates.Through simulation test and measurement in the vacuum environment,the results show that this kind of design method for broadband high-power directional coupler can effectively suppress the multipactor effect,which the working performance of the coupler is ensured.