الفهرس Only 14 pages are availabe for public view
 |  | from | 80 |  |  |
| | | from | 80 | | |
Abstract
Some methods of antenna synthesis will be studied well, because a very common . request is to design an antenna whose far-field pattern process nulls in a certain directions. Other common requests are for the pattern to exhibit a desired distribution, narrow bearnwidth and low sidelobes. Another category requires that the patterns exhibit a desired distribution in the entire visible region. This is referred to as beam shaping, and it can be accomplished using the Fourier transform and the Woodward¬Lawson methods.
A third group includes techniques that produce patterns with narrow beams and low side lobes. The Dolph- Tschebyscheff method can accomplish these requirements. Other techniques that belong to this family are the Taylor line source (Tshebyscheff error) and the Taylor line source (one-parameter).
The synthesis technique will be followed with a brief discussion of continuous aperture distributions (rectangular and circular).
A one-parameter circular aperture distribution has been discussed and for comparison with other distributions, for any sidelobe ratio, the bearnwidth can be narrowed by flattening the sidelobe envelope. Thus there are tapered sidelobe distributions with bearnwidth narrower than that of the one-parameter aperture. Similarly, there are aperture distributions with tapered sidelobes and with higher aperture efficiency.
The one-parameter distribution, because of the construction of the pattern through adjustment of zeros, represents a practical compromise between narrow bearnwidth, high efficiency. And the single parameter allows tradeoff studies to be readily made.