Antenna module and design method thereof

An antenna module, comprising:

• a reflective superstrate, comprising a first surface and a second surface, wherein the first surface is opposite to the second surface;
• an antenna substrate, comprising a third surface and a fourth surface, wherein the third surface is opposite to the fourth surface;
• an antenna, disposed on the third surface;
• and
• a reflective pattern, formed on the first surface and facing the antenna, wherein a reflection gap is formed between the first surface and the third surface, the reflective pattern provides a first reflection phase angle, the third surface provides a second reflection phase angle, the first reflection phase angle comprises a first determined phase angle Δ1, the first determined phase angle Δ1 is not 0°, the first reflection phase angle is about −(180°−Δ1), the second reflection phase angle comprises a second determined phase angle Δ2, the second reflection phase angle is about −(180°−Δ2), a dimension of the reflection gap is directly proportional to a total predetermined phase angle Δ=Δ1+Δ2, and the total predetermined phase angle is between 0°˜90°, wherein the reflective pattern comprises a plurality of reflective units, each reflective unit comprises a major axis and a minor axis, the reflective units are equidistantly arranged along a first direction, and the minor axes of the reflective units are parallel to the first direction, wherein the reflective units are arranged into a 4×1 matrix.