A Novel Metal-Only OAM Transmitarray With Dual-Layer Configuration

In this paper, a novel orbital angular momentum (OAM) transmitarray antenna is proposed. Up to date, existing works on OAM transmitarray antenna use at least three metal layers. Compared to these researches, the proposed antenna has only two layers which can realize a full 360 degrees phase shift in the case of a transmission magnitude greater than -1dB. Dual-layer metal- only transmitarray antenna effectively reduces the antenna profile and dielectric loss. Based on the proposed element, an OAM transmitarray antenna composed of 256 elements is simulated by HFSS. The experimental results show that the proposed antenna can generate OAM wave with l = +1, its divergence angle and maximum gain are about 4 degrees and 21.3dB, respectively. The aperture efficiency is 12.9% at 9.5GHz.