  The possibility of continuous tuning of the spectral properties of two types
of planar metamaterials based on the moire effect by changing their geometric
parameters is demonstrated both experimentally and numerically. It is shown
that for a one-dimensional moire metamaterial obtained by superposition of two
microstrip photonic crystals with close periods, the position of the stop band
in the spectrum can be controlled by changing these periods. For the
two-dimensional moire metamaterial formed by two identical periodic crossed
structures with hexagonal symmetry, the ability to control the frequency of the
surface state mode by changing the crossing angle of these structures relative
to each other has been experimentally and numerically shown. It is numerically
demonstrated that if the moire metamaterial is irradiated by the horn antenna,
a surface wave propagating in the metamaterial plane appears in all directions
beginning from its intersection point with the axis of the incident wave beam.
From the application point of view, moire metamaterials of this type can be
considered as promising prototype of microwave filters, whose spectral
properties can be continuously and smoothly mechanically rearranged.
