THEORETICAL AND EXPERIMENTAL STUDIES OF ANTENNAS AND ARRAYS IN A PARALLEL-PLATE REGION
Abstract
The integral equation for the current on the antenna has been formulated using Green's theorem and a suitable Green's function based on the method of images; the resulting equation has been solved by expressing the current as a Fou rier series in terms of waveguide modes. It has been shown that in the case of thick antennas the logarithmic term in the current, due to the idealized delta-function generator, makes a marked contribution over a significant length of the antenna and the so-called 'transition' region is much larger than for the free-space antenna. The admittance of the theoretical model can be brought into good agreement with the experimental results by subtracting out infinite gap capaci tance and replacing it by an empirical correction term to account for the input susceptance of the actual feeding gap. An anomaly in the behavior of the antenna at resonance, noticed by Lewin, can be avoided by assuming a complex propagation constant in the guide, due to small but finite losses in the image planes. Closed form expres sions for the current and admittance have been obtained and compared with experimental results. The general agreement is found to be good.
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 05, 1962
- Accession Number
- AD0410102
Entities
People
- B. R. Rao
Organizations
- Harvard University