Highly directional resonant antennas built around photonic crystals

Abstract

A monopole resonant antenna with a very high directivity and gain was fabricated based on a layer-by-layer dielectric photonic crystal having a 3D band gap with mid-gap frequency around 12 GHz. The radiation patterns of the antenna, inserted into the planar defect structures built around a 20-layer photonic crystal, was investigated by H-plane measurements and finite difference time domain simulations. When the antenna was inserted in the cavity, the resonance frequency in the reflection dropped sharply from -5 to -35 dB, indicating that most of the power is radiated out in the presence of the cavity. Assuming negligible absorption, the maximum gain has a value around 300.