Concentric Round Metaloops

This paper presents an antenna system where a small round metaloop, S, and a larger round metaloop,L, are arrayed concentrically on a single dielectric substrate. Metaloop S generates circularly polarized broadside radiation. Metaloop L also generates circularly polarized radiation, but the maximum intensity is directed off the zaxis. The antenna system is designed such that it does not radiate/transmit an RF signal in a specific direction (forbidden direction). To achieve this, the radiation from metaloop L is superimposed onto the radiation from metaloop S, producing a dip in the radiation pattern. It is found that the direction of the dip changes when the input voltages applied to the metaloops are changed. Examples where the dip moves in the elevation and azimuth planes are presented.