Characteristics of Phase-Correcting Fresnel Zone Plates and Elliptical Waveguides

摘要

The primary area of activity has been concentrated on the investigations relatingto Fresnel zone plate antennas. A secondary effort has dealt with the characteristics of propagation in waveguides of elliptical cross section. In both cases, applications at microwave and millimeter-wavelengths have been emphasized. Thorough literature searches were conducted, and the results are given in Appendices A and B. The zone plate work has dealt with both transmission and reflection types, and has included considering the off-axis-fed cases. In the latter case, the plate may consist of elliptical zones, rather than the usual circular configuration. In general, the characteristics studied include far-field patterns, focal region fields, off-axis performance, bandwidth, and aberrations. In the case of Propagation in elliptical waveguides, the attenuation and modal properties were studied for enclosed metal waveguides, coaxial transmission lines, and various surface waveguides. Contributions to these investigations were made by Dr.-Glenn Smith and Dr. Helen C. Wiltse and Messrs. C.A.Barrett, J.E. Garrett, T.H. Gfroerer, and K. Demino. Fresnel zone plate antennas, Elliptical waveguides.