Coupling reduction in a 2×2 high dielectric constant EBG patch array

High dielectric EBG substrates can be used in patch antenna configurations to reduce size and mitigate substrate modes keeping reasonable radiation efficiency values, η≫0.55. At the same time, in array configurations they avoid grating lobes and scan blindness phenomenon at the same time, as distance and coupling between elements can be reduced. In this paper a 2×2 array configuration using these high dielectric constant (ZTT) EBG substrates is presented. The array has been fabricated and measured showing the coupling reduction achieved by the inclusion of the EBG in a configuration with a distance between elements lower than 0,5λ0. This short distance together with the coupling reduction results in a configuration which doesn't suffer from grating lobes and scan blindness problems.