Directive photonic-bandgap antennas

This paper introduces two new photonic bandgap (PBG) material applications for antennas, in which a photonic parabolic reflector is studied. It is com posed of dielectric parabolic layers associated to obtain a PBG material. T he frequency gap is used to reflect and focus the electromagnetic waves. Th is device has been designed using a finite-difference time-domain (FDTD) co de. FDTD computations have provided the theoretical reflector's directivity . These results are in good agreement with measurements, and it appears tha t the PBG reflector presents the same directivity as a metallic parabola. A second application uses a defect PBG material mode associated with a metal lic plate to increase the directivity of a patch antenna. We explain the de sign of such a device and propose experimental results to validate the theo retical analysis.