REFLECTIVE MIRROR ANTENNA DEVICE

PURPOSE:To reduce th leakage power and to improve the radiation characteristics, by shaping the magnifying glass face of a subreflective mirror into such form that radiant beams of a main reflective mirror are arranged in the main direction. CONSTITUTION:Radio waves incident from a phase center F1 of a primary radiator 1 to a point D1 on a magnifying glass face part 7 of a subreflective mirror 5 are reflected at th point D1 and go to a point C1 on the subreflective mirror 6. Radio waves reflected at this point C1 advence to a point M on a main reflctive mirror 3 and go to a point B1 in the space. The form of the magnifying glass face part 4 is so determined that the angle made by a vector MB1 and the axis of the main reflective mirror 3 is smaller. Next, radio waves from the phase center F1 toward the subreflective mirror 5 become spherical waves as usual and are reflected by a magnifying glass face part 8 of the subreflective mirror 5 and go to the point M on the main reflective mirror 3 and go from the point M to a point B2 in the space. The form of the magnifying glass face part 8 is so determined that the angle made by a vector MB2 and the axis of the main reflective mirror 3 is smaller.