Influence of metallic photonic bandgap (MPBG) materials interface on dipole radiation characteristics

The MPBG interface influence on half-wavelength dipole radiation characteristics—radiation pattern and input impedance—is analyzed. This study concerns frequency operation within or without an MPBG bandgap. A first analysis has been performed by replacing a wire of a 2-D square lattice MPBG by a dipole. Then, the study of dipole–MPBG distance is presented for different MPBG structures, and is compared to simple and gridded corner reflector characteristics. This demonstrates that the input impedance value can be controlled, and depends on the MPBG structure dimensions and on the dipole position within this structure. It shows that some improvement of angular filter specifications can be obtained when the MPBG interface is no longer a plane.