Search results
Results From The WOW.Com Content Network
A parabolic antenna is an antenna that uses a parabolic reflector, a curved surface with the cross-sectional shape of a parabola, to direct the radio waves. The most common form is shaped like a dish and is popularly called a dish antenna or parabolic dish. The main advantage of a parabolic antenna is that it has high directivity.
English: Diagram showing the most common types of parabolic antenna feeds. The reflecting surfaces are shown in red , the feed antenna in green , and typical supporting structures in blue . A few typical rays are shown, in black.
A beam waveguide antenna is a type of complicated Cassegrain antenna with a long radio wave path to allow the feed electronics to be located at ground level. It is used in very large steerable radio telescopes and satellite ground antennas, where the feed electronics are too complicated and bulky, or requires too much maintenance and alterations, to locate on the dish; for example those using ...
{{Information |Description=Diagram showing types of parabolic antenna feeds.}} |Source={{own}} |Date=2010-11-25 | Chetvorno |Permission=I, Chris Burks , the author of this work, release it File usage No pages on the English Wikipedia use this file (pages on other projects are not listed).
The category of simple antennas consists of dipoles, monopoles, and loop antennas. Nearly all can be made with a single segment of wire (ignoring the break made in the wire for the feedline connection). [citation needed] Dipoles and monopoles called linear antennas (or straight wire antennas) since their radiating parts lie along a single ...
A new form of omnidirectional satellite antenna, which does not use a directed parabolic dish and can be used on a mobile platform such as a vehicle was announced by the University of Waterloo in 2004. [12] The theoretical gain (directive gain) of a dish increases as the frequency increases. The actual gain depends on many factors including ...
Main types of parabolic antennas. An offset dish antenna or off-axis dish antenna is a type of parabolic antenna.It is so called because the antenna feed is offset to the side of the reflector, in contrast to the common "front-feed" parabolic antenna where the feed antenna is suspended in front of the dish, on its axis.
In most antennas, the radiation from the different parts of the antenna interferes at some angles; the radiation pattern of the antenna can be considered an interference pattern. This results in minimum or zero radiation at certain angles where the radio waves from the different parts arrive out of phase , and local maxima of radiation at other ...