Periodic metal array structure

A periodic metal array structure located between two antenna modules to form a planar antenna array system and comprising a plurality of rows of metal unit assemblies arranged in a transverse direction, wherein each adjacent two metal unit assemblies are spaced apart from each other by a first interval, each of the metal unit assemblies comprises a plurality of metal units connected to each other in a longitudinal direction, and each of the metal units has:

• a first longitudinal strip extending in the longitudinal direction;
• two first transverse strips extending in the transverse direction and respectively connected with top and bottom ends of the first longitudinal strip, wherein at least one of the first transverse strips is configured to be connected with a first transverse strip of another one of the metal units;
• two second longitudinal strips extending in the longitudinal direction and respectively disposed on left and right sides of the first longitudinal strip, each having a longitudinal length shorter than a longitudinal length of the first longitudinal strip, and being spaced apart from the first longitudinal strip by a second interval;
• and
• two second transverse strips extending in the transverse direction and disposed on the left and right sides of the first longitudinal strip respectively, each of the second transverse strips having one end connected to the first longitudinal strip and the other end connected to a corresponding one of the second longitudinal strips.