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One of the important parameters to enhance the efficiency of Fresnel Zone Plate Antenna (FZP A) is the phase efficiency. This efficiency deepens on the number of layers in the multi-layer FZP A and dielectric materials in the multi-dielectric FZP A. Because the number of Fresnel Zone is limited by the mechanical and practical restrictions, this efficiency is also related to these parameters. Therefore, to obtain the maximum gain or perform optimum design of FZP A one must
choose suitable values for the number of
Fresnel zones and their radii, focal length, characteristics of feed and also must consider practical and mechanical restrictions. In this paper, methods for analysis of these structures are first introduced, then, a proper method for analyzing the structure is chosen. Second, for a given FZPA diameter and a given feed with symmetrical radiation pattern, a procedure is introduced to obtain optimum values for the focal length, radii of Fresnel Zones and simulated feed parameter, so that they yield the maximum gain and desired side lobe level of radiation pattern. Finally the simulated and measurement results are compared.