Control of the radiation properties of a FSS loaded leaky-wave antenna

This work presents a novel leaky-wave antenna (LWA), conceived from the insertion of a dipole-based frequency selective surface (FSS) into a top-open rectangular waveguide. It is explained how the printed circuit has the ability to control the radiation rate of the leaky modes that propagate through this structure at a certain frequency. This attribute makes possible the tapering of the radiation diagram of the LWA. In particular, it is possible to reduce the sidelobes level. This feature will be illustrated by performing a cosine tapered design. Good agreement is observed when comparing the results obtained from leaky-mode theory with full-wave simulations. Finally, the limitations of this tapering procedure will also be presented.