On the control of radiation directivity of elementary source coupled in electromagnetic crystals

Abstract

A directivity of radiation from a line source coupled to 2D electromagnetic crystals is investigated using a Fabry-Perot resonator model for the coupled radiating structure. It is shown that the directivity is characterized by the transmission windows of the electromagnetic crystals in the frequency and angular spectral domains and the transverse resonance condition in the space surrounded by the electromagnetic crystals. A directivity diagram that relates the transmission and reflection spectra of electromagnetic crystals and the size of the resonator to the radiation patterns attainable by a line source is presented. Several numerical examples validate the usefulness of the diagram for designing unique electromagnetic crystal antennas.