Analysis of the electromagnetic radiation generated by a multipactor discharge occurring within a microwave passive component

Abstract

Multipactoring is a non-linear phenomenon that appears in high-power microwave equipment operating under vacuum conditions and causes several undesirable effects. In this paper, a theoretical and experimental study of the RF spectrum radiated by a multipactor discharge, occurring within a realistic microwave component based on rectangular waveguides, is reported. The electromagnetic coupling of a multipactor current to the fundamental propagative mode of a uniform waveguide has been analysed in the context of the microwave network theory. The discharge produced under a single-carrier RF voltage regime has been approached as a shunt current source exciting such a mode in a transmission-line gap region. By means of a simple equivalent circuit, this model allows prediction of the harmonics generated by the discharge occurring in a realistic passive waveguide component. Power spectrum radiated by a third-order multipactor discharge has been measured in an E-plane silver-plated waveguide transformer, thus validating qualitatively the presented theory to simulate the noise generated by a single-carrier multipactor discharge.

Simple model of the rf noise generated by multipacting electrons

“…5). It should be noted that the ratio between the heights of the peaks of different harmonics is also close to that given by equation (11) However, a more detailed study of this spectrum (taking into account the non-propagating modes) revealed the existence of a sub-harmonic current peak. In contrast to the theoretical predictions for multipactor with a single electron sheet, the height of the revealed sub-harmonic peak is less than the height of the first harmonic peak, which makes it possible to conclude that in the simulations there were three electron sheets but with different number of electrons in each.…”

“…A particular model must be developed for each particular rf circuit. Examples of simulations for some rf filter configurations can be found in [9][10][11][12].…”

High-Power Filter Design in Waveguide Technology: Future Generation of Waveguide Satellite Filters in Payloads Handling Increasing Bit Rates and Numbers of Channels

“…In order to perform multipactor measurements, an experimental setup such as the one described in [76] can be implemented. It must include different local and global detection methods, such as electron probes, a nulling system of the forward/reverse power at the carrier frequency, or harmonic detection methods.…”

Investigación en técnicas numéricas basadas en ecuación integral para el análisis y diseño de dispositivos de microondas para comunicaciones espaciales

“…This is due to the dependence existing between the number of accessible modes and the Taylor approximation of the kernel. This device was used in Jiménez et al (2010) to verify the theoretical model proposed to predict the harmonics generated by the multipactor discharge occurring in realistic passive waveguide components in space conditions. We use this transformer here as an example to validate the advantages in terms of performance of the new MEN theory.…”