Helical and meander super-wide-band structures are applied to
communication equipment, measuring techniques, wide-band oscillographic
traveling-wave tubes and other microwave devices.
Various models and methods are used for analysis of helical, meander
and other types of slow-wave structures. The generalized theory of helical,
meander and other types of slow-wave structures is based on the models
consisting of the segments of multi-wire lines. However, there are some
problems that are not solved yet.
Dielectric holders are necessary for helical and meander electrodes.
These holders have influence on the properties of the structures, but this
influence is not investigated comprehensively.
We have improved the model of meander structure with axial symmetry,
have derived its dispersion equation, expression of input impedance and have
estimated the influence of the dielectric holders of meander electrodes upon
the electrical characteristics of meander slow-wave structures.
Slow-wave structures with constant moderation coefficient are
necessary for the super-wide-band traveling-wave cathode-ray tubes and other
microwave devices. According to the dispersion equation and frequency
characteristics, stray capacitances between U-parts of meander electrode must
be reduced in order to decrease the dispersion of phase velocity in the
meander structure. Stray capacitances may be eliminated by using comb-shape
dielectric holders for meander electrodes.