The possibility to achieve a continuous tuning of the spectral properties in the case of two types of planar metamaterials based on the moire effect is demonstrated both experimentally and numerically. Tuning spectral characteristics are provided by changing geometric parameters of above-mentioned metamaterials. 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 stopband in the spectrum can be controlled by changing these periods. We also consider the two-dimensional moire metamaterial formed by two identical periodic crossed structures with hexagonal symmetry. The ability to control the frequency of surface state mode by changing the crossing angle of these structures relative to each other has been shown experimentally and numerically. 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. In practice, moire metamaterials of this type can be considered as a promising prototype of microwave filters, whose spectral properties can be continuously and smoothly mechanically rearranged.
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