Multipactor-resistant low-pass harmonic filters with wide-band higher-order mode suppression

In this paper, a multipactor analysis of a new type of high-power low-pass harmonic filter in rectangular waveguide technology is performed. The filter is designed following a novel technique which permits to obtain a low-pass filtering function with suppression of the fundamental and all the higher-order modes over a wide frequency band. This is achieved by means of a smooth variation of the waveguide height and width. Although much larger minimum mechanical gaps than the ones achieved with classical techniques can be obtained with the proposed method, the smooth profile of the novel filter topology is enough to obtain a dramatic increase in the power-handling capability of the device. This is proved by high-power simulations and measurements.