Citation
Abstract
It is well known that paraboloidal antenna aperture efficiency is enhanced by providing aperture illumination which approaches uniformity in amplitude, phase, and polarization. For dual-reflector antenna systems, such as those used in the DSN, a high degree of uniformity is possible by use of specially shaped reflector surfaces (Ref. 1). As a long-range solution to the problem of achieving high aperture efficiency, this approach is attractive because it is inherently broadband and requires only a simple feedhorn of the type presently being utilized in the DSN. An alternate approach for achieving high aperture efficiency (suggested by D. Bathker of the Communications Elements Research Section) involves use of the existing antenna reflecting surfaces together with a more complex multimode feedhorn. This approach is attractive from an implementation standpoint. Preliminary experimental results (obtained by R. Thomas of the Communications Elements Research Section) are promising. The multimode technique does, however, suffer from bandwidth difficulties, at least with presently known mode-generation techniques. To assist and guide the multimode feedhorn experimental effort, a new computer program has been developed which computes horn radiation patterns and bandwidth properties as a function of horn geometry. This article describes the analytical technique utilized and agreement with existing experimental data.
Details
- Volume
- XIII
- Published
- February 15, 1973
- Pages
- 92–107
- File Size
- 995.3 KB