An cassegrain reflector antenna with an elliptic beam of large axial ration

In this article, a novel Cassegrain antenna with a variable focal distance and a variable edge subtend angle for forming an elliptic beam of large axial ratio is proposed. Not only the simple and efficient designing method but also the calculate theory of radiation patterns are proposed. One model with an axial ration of 1.37 is fabricated and its measured and calculated results show that this reflector not only can achieve elliptic beam of large axial ratio, but also has reasonable side lobe levels and antenna efficiency taking out of the blocking effect within a broad frequency range.