High-isolation dual-frequency dual-polarization millimeter wave array antenna

The invention discloses a high-isolation dual-frequency dual-polarization millimeter wave array antenna which sequentially comprises a periodic metal coating, a parasitic antenna layer, a radiating antenna layer and a metal ground layer from top to bottom. The periodic metal coating is arranged above the array antenna and is an inclusion material consisting of dielectric layers with the same dielectric constant and periodically arranged metal patterns; the parasitic antenna layer comprises a parasitic antenna array composed of at least one resonant parasitic antenna unit; the radiating antenna layer comprises a radiating antenna array composed of at least one multi-frequency resonant antenna unit; the metal ground layer is provided with a feed port, and the feed port is connected with the corresponding multi-frequency resonant antenna unit through a feed column. The double-layer antenna structure reduces the size of the antenna, the periodic metal coating improves the isolation between the antenna units, and