Modeling and characterization of microwave breakdown at atmospheric pressure in OMUX filters

For output multiplexer (OMUX) filters placed in telecommunication satellites, microwave breakdown happens in an involuntary and undesirable way during tests at atmospheric pressure. This avalanche phenomenon is due to exponential growth of the electronic density caused by thermoelectronic emission under strong electromagnetic field magnitude. In this paper, our objective is to model and characterize experimentally multipole OMUX filters composed with coupled cavities. For identifying the element responsible for the breakdown, the electric field is calculated within each cavity and each iris. In order to characterize the breakdown phenomenon, we proposed an experimental test bench and we measured the power, both at the input and at the output of the filter. The article details the theoretical breakdown prediction and the experimental setup for such a structure. © 2013 Wiley Periodicals, Inc. Int J RF and Microwave CAE 24:46–54, 2014.