A frequency-scanned antenna was designed that operates over a 10% frequency bandwidth performing at least a 10 degrees scan range. The antenna operates between 8.5-9.5 GHz, and the shape of the reflector is predicted to be optimally focused at 9.0 GHz. For a cylindrical reflector the angle of incidence to the normal of the surface varies between theta =17 degrees -35 degrees . The computed optimized performance over this range is shown. A simplified model was used to predict the radiation pattern of the antenna system. According to this model, the radiation pattern of the dipole array was computed with the amplitude and phase of each dipole given by the distance to the feed and the tapered illumination of the feed. It is seen that the suppression of the basic beam is of the order of 20 dB. For the frequency-scanned beam, the correspondence with the simplified theory is excellent.
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