1-2hit |
Hiroshi KUBO Tsuyoshi MUKAI Atsushi SANADA
A compact, nonradiative, and easy fabricated left-handed material composed of planar circuit-type resonators in a cutoff waveguide is proposed. It is shown that the TE-type evanescent field is equivalent to the field in ε-negative material and the resonator works as a particle with negative permeability. The existence of a left-handed mode is ensured by a field distribution and a dispersion relation. After showing that the two constituents have an influence on the permittivity or the permeability of the material, on the basis of an idea of impedance, the material is matched to a conventional waveguide. Finally the material can be applied to a left-handed leaky-wave antenna.
Hiroshi KUBO Tsuyoshi MUKAI Atsushi SANADA
New strip arrangements for high Q or high effective permittivity are proposed for artificial dielectric resonators in a waveguide. The quality factor and the effective permittivity are discussed by changing strip arrangement composing the artificial dielectric. Concentrating strips from both sides to the middle in the waveguide leads to increase of unloaded Q. The value becomes high to several thousands by decreasing dielectric loss of the material. Interdigital strip arrangement makes the effective permittivity very high. A resonator of the strip arrangement has effective permittivity over 800 and unloaded Q over 1000. Moreover the resonator exhibits a good spurious characteristic with no unnecessary resonant mode throughout several harmonics range.