An annular parabolic trough reflector array for orbital angular momentum beam focusing

In this paper, we proposed a reflector antenna array with annular parabolic trough reflecting surface for generating the orbital angular momentum modes. In this array, eight antenna elements are evenly distributed on the circular focal line of the revolutionary parabolic trough surface structure. Comparing to the array without reflecting surface and the array with conventional parabolic reflecting surface, this reflector array shows good performance in focusing the electromagnetic waves, and thus obtains higher gains at the first beams of all the transmitted orbital angular momentum modes.