A Dual-CP Multibeam Transmit-Array Antenna Based on Anisotropic Impedance Surfaces and Hybrid Phase Compensation

In this letter, a dual-circularly polarized (dual-CP) multibeam transmit-array (TA) antenna is proposed and demonstrated based on anisotropic impedance surfaces (AISs) and hybrid phase compensation strategy. A set of eight fully planarized TA cells based on cascaded AISs are designed with a constant dynamic phase difference between each other, possessing a periodicity of 0.48?(0) x 0.48?(0) and a total thickness of 0.71?(0), where ?(0) is the free-space wavelength at center frequency. By introducing Berry phase determined rotation angles on the eight designed cells, dual-CP transmissive phase delays can be achieved independently. Moreover, planar dual-CP antenna arrays are designed and utilized as the feed cluster of the multibeam TA. The bifocal dual-CP multibeam TA antenna generates eight RHCP beams and eight LHCP beams. The measured peak gain values are between 21.1 and 23.7 dBic, whereas the AR values are all below 3 dB for all the beams.

Automated summary

In this paper, a dual-circularly polarized multibeam transmit-array antenna is proposed using anisotropic impedance surfaces and hybrid phase compensation strategy. The antenna array consists of eight planarized transmit-array cells with constant dynamic phase difference and Berry phase determined rotation angles. The measured results show that the antenna generates eight RHCP beams and eight LHCP beams with high peak gain values and low axial ratio.