Characteristics of phase-correcting fresnel zone plates and elliptical waveguides
Abstract
The primary area of activity has been concentrated on the investigations relating to 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.
- Publication:
-
Final Report
- Pub Date:
- February 1994
- Bibcode:
- 1994gtri.rept.....W
- Keywords:
-
- Antenna Radiation Patterns;
- Fresnel Region;
- Microwave Antennas;
- Wave Propagation;
- Waveguides;
- Aberration;
- Bandwidth;
- Coaxial Cables;
- Far Fields;
- Millimeter Waves;
- Electronics and Electrical Engineering