(IEEE, 2016) Teberio Berdún, Fernando; Arregui Padilla, Iván; Gómez Torrent, Adrián; Arnedo Gil, Israel; Chudzik, Magdalena; Zedler, Michael; Goertz, Franz-Josef; Jost, Rolf; Lopetegui Beregaña, José María; Gómez Laso, Miguel Ángel; Ingeniería Eléctrica y Electrónica; Ingeniaritza Elektrikoa eta Elektronikoa
A novel chirping technique is applied to the design
of very high-power waveguide harmonic low-pass filters. The
technique could be used, for instance, to avoid multipactor
testing in multicarrier systems such as the output multiplexer
of a communications satellite. The novel chirped filter shows
low insertion loss, all higher order mode suppression, and broad
stopband rejection up to the third harmonic. This paper focuses
on the maximization of the filter power-handling capability
without affecting its excellent frequency behavior. Given a certain
frequency response, the E-plane mechanical gap of the structure
and the length (in the propagation direction) of the waveguide
sections between its constituent bandstop elements can be considered
to improve the high-power behavior. However, the power
performance may not be sufficient yet in some applications if
we wish, for instance, multipactor testing to be avoided. This
becomes feasible by chirping the length (in the propagation
direction) of the bandstop elements. An example for Ku band is
discussed for relevant frequency specifications. An improvement
from ∼8 kW (non-chirped filter) to more than 100 kW (chirped
filter) is obtained. As a reference, the equivalent waffle-iron filter
can handle only 0.15 kW. Such high-power threshold levels have
never been reported before for such kind of filters.
