The paper focuses on λ/4 monopole antennas located in a meta-material that exhibits simultaneously negative values of effective permeability and permittivity within a microwave frequency band, as well as our experimental study in an anechoic chamber. The experimental results show that the electromagnetic waves radiated by the monopole are negatively refracted at the interface between the meta-material and the air at certain directions. In addition, the radiation pattern of the monopole in the meta-material is directional while it is non-directional without the meta-material.
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