Surface Wave Scattering Reduction Using Beam Shifters

A surface wave beam shifter is designed using ring-mushroom unit cells. The unit cell consists of a rectangular ring that surrounds an interior patch and plated via. The unit cell is anisotropic, and surface waves propagate with different directions of phase velocity and power flow. Two adjacent regions are designed such that the shift direction in each region is mirrored. The result is that an incident beam is split apart, and power does not radiate in the original direction of the beam. It is shown that an object placed in line with a source scatters surface waves in multiple directions from the object. By using a beam-splitting surface, the incident beam avoids the object, and scattering is significantly reduced. When the wave is incident in series with the two beam shifters, the surface shifts the wave in one direction followed by a shift in the opposite direction.