A technique for predicting specular reflections from reflectarrays

This paper has presented two computational techniques for predicting scattered and specular reflection components from reflectarray antennas. The variant of the technique that targets just the specular reflection is computationally very efficient. Both techniques allow for accurate characterization of specular reflections in reflectarrays and have been successfully used to demonstrate the relationship between reflectarray cell size and the amount of specular reflection produced. The effective area of a patch element has been demonstrated to be an important factor in selecting the size of reflectarray elements to reduce the detrimental effect of specular reflections on the reflectarray gain.