High efficiency short backfire antenna using anisotropic impedance walls

A method for providing a high efficiency short backfire antenna (SBFA), the method comprising:

• providing a conductive cylindrical reflector that is configured to collect or to radiate electromagnetic waves, the cylindrical reflector having a reflector base and a reflector wall;
• and
• providing a feed structure that is electromagnetically coupled to the cylindrical reflector,
• wherein:
• the cylindrical reflector is a hollow cylinder,
• the feed structure comprises a hexagonal patch element assembly and a perforated hexagonal sub-reflector,
• the reflector base is formed in a hexagonal shape,
• the reflector wall includes an inside liner, and
• the inside liner comprises a dielectric material and includes an anisotropic impedance surface comprising longitudinal strips.

An antenna array comprising:

• a plurality of high efficiency short backfire antenna (SBFA) elements, each SBFA element comprising:
• a conductive cylindrical reflector comprising a reflector base and a reflector wall and configured to collect or to radiate electromagnetic waves;
• and
• a feed structure electromagnetically coupled to the cylindrical reflector and configured to convert collected electromagnetic waves to an induced electrical current or to convert a feed electrical current to electromagnetic waves for transmission by the SBFA,
• wherein:
• the feed structure comprises a hexagonal patch element assembly and a perforated hexagonal sub-reflector,
• the cylindrical reflector is a hollow cylinder,
• the reflector base is formed in a hexagonal shape,
• the reflector wall includes a dielectric liner formed on an inside surface of the cylindrical reflector, and
• the dielectric liner is covered with an anisotropic impedance surface.