Beam transformation using reflectarray at millimeter wave length

In millimeter wave and THz band, the wave always propagates in the form of beams, such as Gaussian beam, Bessel beam. The generation, control, and transform of these beams are very important. This paper proposed a reflectarray to transform these beams at millimeter wave length. By properly design the reflect phase shift at each position on the reflectarray, a quasi-Gaussian beam is transformed into Gaussian beam and a Gaussian beam is transformed into zero-order Bessel beam. The simulated results show that the beam transformation efficiency of the reflectarray is approaching the transparent transformation technology.