A very small aperture concentric array radial line slot antenna

A radial line slot antenna (RLSA) is a high efficiency and high gain planar antenna for DBS reception. It utilizes an oversized waveguide which maintains cylindrical travelling waves with rotational symmetry. It excites slots spirally arrayed on the upper surface of the waveguide. Then the conductor loss of an RLSA is very small and negligible. A high efficiency is expected in principle even in the high gain range. The simple structure of an RSLA is also advantageous for mass production. The authors propose a new concept of a concentric array RLSA (CA-RLSA). They present the basic design of the CA-RLSA.