Patent ID: 7439913

Claim:
A microstrip reflectarray antenna for transmitting and receiving a high frequency signal, comprising: a ground plate; a reflecting plate with an upper surface, and a plurality of microstrip antenna units locating on the upper surface; each of the microstrip antenna units consisting of an inner ring and an outer ring; a plurality of supporting units for supporting the reflecting plate above the ground plate, so as to maintain a predetermined distance between the reflecting plate and the ground plate; and a signal transmitting unit locating above the reflecting plate for transmitting and receiving the high frequency signal; wherein, the size of the outer ring corresponds to the location of the outer ring on the upper surface of the reflecting plate; each of the microstrip antenna units comprises an outer ring with a first diameter and an inner ring with a second diameter, and there is a first ratio relationship between the first diameter of the outer ring and the second diameter of the inner ring of the same microstrip antenna unit; each of the outer rings has at least one first slot, and each of the inner rings has at least one second slot, and wherein the outer ring of each of the microstrip antenna units has two first slots.