A Single-Layer Reflectarray Antenna Carried with Wideband OAM Beams

A single-layer phoenix patch element is utilized to design a reflectarray antenna for generating wideband OAM beams in this paper. The proposed reflectarray element is composed of an inner circle and two outer rings. By changing the radius of the middle ring, 360 degrees linear reflection phase ranging from 9 GHz to 13 GHz can be achieved only with single layer. Based on the characteristics of the element, a 15 x 15 full-fledged reflectarray carried with OAM beam has been designed. The reflectarray is fed by a linearly polarized horn. Simulated results show that the proposed single-layer phoenix patch reflectarray is capable of producing vertex beams from 9 GHz to 12 GHz. A 28.5% bandwidth proves that the proposed reflectarray makes a good performance in a broad frequency band.