Ridged Structure of Coaxial Cavity for Raising the Multipactor Threshold of Microwave Switch

Abstract

Microwave devices, including microwave switches, are more prone to high power discharge in the L-band. In order to improve the multipactor threshold of coaxial SPDT switches, a rectangular coaxial cavity with a ridged structure is proposed. The introduction of the ridged structure can effectively change the motion path and time of secondary electrons from the inner conductor to the surface of the cavity, thus suppressing the resonant discharge effect of electrons. Compared with the method of changing the surface treatment, the multipactor threshold is increased by 4.1 dB with no additional insertion loss. The structure is easy to manufacture and can be extended to other high-power demanding products, such as power dividers and filters.

Keywords

• Coaxial microwave switch
• multipactor threshold
• ridged structure