Dual-circularly polarized topological patch antenna with pattern diversity

Recently, the topological properties of composite vortices, i.e., the superposition between vortex modes of a different order, have proven effective in manipulating the radiation properties of patch antennas and making them suitable for new operative scenarios. In this paper, we exploit these properties to design a multi-antenna system exhibiting both pattern- and polarization-diversity. The low mutual coupling and the possibility to steer two orthogonal polarized elds in different directions, make this radiating element an optimal candidate for antenna diversity or MIMO systems and, thus, for increasing signal quality or channel capacity of a communication system.