Narrow angle lens antenna for THz applications

Dielectric covered antennas have been extensible used in microwaves. They are usually designed with dielectric quarter wavelength super-layers or with frequency selective surfaces. The main drawback of these antennas is that their BW is inversely proportional to the directivity. The new geometry proposed here makes use of a silicon lens instead of dielectric super-layer. In this case, the directivity is associated to the lens diameter instead of the leaky poles; therefore the BW will not depend anymore on the directivity but just on the initial cavity. The main advantage of this antenna when it is used in the THz band is related to the fabrication. Since only a small sector of the lens is required (approximately 12deg), the lens can be fabricated using microfabrication techniques. This will allow the fabrication of a whole array of lenses on the same wafer. Another advantage is that a simple quarter wavelength matching layer of the lens will be more efficient if a smaller angular region of the lens is used. Finally the feed used here is a standard waveguide which is easily integrable with Schottky diode.