A dual-polarized double-layer microstrip antenna with a metasurface structure is proposed for 5G and 5G Wi-Fi. A total of 4 modified patches are used for the middle layer structure, and 24 square patches are used for the top layer structure. The double-layer design has achieved -10 dB bandwidths of 64.1% (3.13 GHz~6.08 GHz) and 61.1% (3.18 GHz~5.98 GHz). The dual aperture coupling method is adopted, and the measured port isolation is more than 31 dB. A low profile of 0.096λ0 is obtained (λ0 is the wavelength of 4.58 GHz in the air) for a compact design. Broadside radiation patterns have been realized, and the measured peak gains are 11.1 dBi and 11.3 dBi for two polarizations. The antenna structure and E-field distributions are discussed to clarify its working principle. This dual-polarized double-layer antenna can accommodate 5G and 5G Wi-Fi simultaneously, which can be a competitive candidate for 5G communication systems.
Keywords: double-layer; dual-polarized; low-profile; microstrip antenna; periodical structure; wideband.