Array antenna device

An array antenna device comprising:

• a first substrate comprising a first feed point;
• a second substrate provided under the first substrate and comprising a second feed point;
• and
• a 180° hybrid circuit which feeds the first feed point and the second feed point with a phase difference of zero or 180°,
• wherein the first substrate comprises:
• a first dielectric layer;
• a first radiating element array formed by arranging first radiating elements in an array on the first dielectric layer;
• first feed lines provided on the first dielectric layer and connecting the first feed point to the first radiating elements by a pattern of lines of equal length, respectively, such that the first radiating elements form a linearly polarized wave in a first polarization direction;
• a first ground conductor layer provided under the first dielectric layer;
• and
• a second dielectric layer provided under the first ground conductor layer,
• the second substrate comprises:
• a third dielectric layer located under the second dielectric layer;
• a second radiating element array formed by arranging second radiating elements in an array on the third dielectric layer such that the second radiating elements are opposed to the first radiating elements, respectively;
• second feed lines provided on the third dielectric layer and connecting the second feed point to the second radiating elements by a pattern of lines of equal length, which is the same as the pattern of the first feed lines, respectively, such that the second radiating elements form a linearly polarized wave in a second polarization direction orthogonal to the first polarization direction;
• and
• a second ground conductor layer provided under the third dielectric layer,
• the first ground conductor layer has openings in positions opposed to the first radiating elements and the second radiating elements, and
• connecting portions of the first feed lines to the first radiating elements are formed in a direction orthogonal to a direction of connecting portions of the second feed lines to the second radiating elements.