dipole

You might be an inginer or someone with no techic backgroud, but it is still a good thing to know how a dipole antena functions and what are its most basic features. At least some time in the past people have had it in their homes and used it, even without knowing it. You may know this type of antenna, because is one of the most known. Most of the times this is used alone, and not together with other antennas. The building of a such antenna is pretty easy. The whole calculation process is quite interesting and easy, but if someone goes into deeper uses, things can get really complicated. 

This antennas have 2 poles that directs the flow of radio frequency from each other. Because of the current and the voltage, the radio signal is radiated. This way the antenna can be connected to the feeder. The current will be distributed sinusoidal with this type of antenna. It will have a maximum peak and other that it will fall to zero near the end of the cycle. That for current flow, while the voltage pattern is different. This will have 2 opposite values, one the is middle and one maximal. So at the center of the process one will be at its highest point, while the other at its lowest. 

antenna

The different uses of dipole antennas are multiple; from military uses to civil uses. The most common use regards the TV antenna. If you never seen one (check the picture), it is distinguished by its two opposite loops. To get the best radio signal, the loops can be adjusted at a certain angle or lenght. The folded dipole antenna is a similar one to this. It is usually used for the FM band. Both dipoles meet each other in the feed point section. Used most of the time for one wavelength. Similar to classi dipole antennas they can be build easily. 

Other types of dipole antennas include the simplest one called the whip. This is the younger brother, as it is a monopole antenna. The whip antennas are less efficient to receive quality signals, compared to dipole ones. Advantages of monopole antennas are they need less space. For dipole antennas it is common the use of towers. Around the country there are many such towers that have dipole antennas on them. Military use the doublets of this antennas. In many cases there are more than one in use and they have special dedicated frequencies.  According to each mission the type of antennas may change and they can have all sorts of other improvements.