Abstract.
The presence of functional connections between the
characteristics of an artificial magnetic conductor, the parameters of
structures with frequency selective surfaces and the dielectric layer determine
the possibility of expanding the range of operating frequencies. An analytical
expression for such relationships is the formula for estimating the phase of
the reflection coefficient from an artificial magnetic conductor obtained using
the theory of electrical circuits and long lines. With the help of the presented
analytical expressions the estimation of ways of expansion of a range of
operating frequencies of an artificial magnetic conductor on the basis of
band-pass frequency selective structures is carried out. UC-PBG structure was
chosen as the basic calculation model. The purpose of numerical calculations of
the frequency dependence of the phase of the reflection coefficient on the
artificial magnetic conductor was to study ways of modifying the basic model of
the artificial magnetic conductor, which provides an extension of the operating
frequency band while maintaining the value of the resonant, i.e., the Central
frequency of this band. Two variants of such modification are considered. The
numerical calculation confirmed that the decrease in the dielectric
permeability of the layer between the frequency selective surface and the
conductive screen while increasing the thickness of the layer and the element
size of the frequency selective structure allows to increase the band of the
operating frequencies of the artificial magnetic conductor. Reduction of the
dielectric permeability of the layer from 10.2 to 1.2 with doubling the layer
thickness and the size of the lattice element allowed to expand the band of
operating frequencies from 9% to 16%. The numerical calculation showed that the
increase in the thickness of the dielectric layer without reducing the
dielectric permeability does not allow to expand the range of operating
frequencies of the artificial magnetic conductor (in contrast to the artificial
magnetic conductor based on capacitive grids).
Key words:
artificial
magnetic conductor, frequency selective surface, numerical
calculation, band of operating frequencies, resonant
frequency.
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