The antenna is a converter that converts the guide wave propagating on the transmission line, transformed into electromagnetic waves propagating in the unbounded medium (usually free space), or conversion. The components used to transmit or receive electromagnetic waves in the radio apparatus. Radio communication, broadcast, television, radar, navigation, electronic confrontation, remote sensing, radio astronomy, etc. Further, in terms of electromagnetic wave transmission energy, the non-signal energy radiation also needs an antenna. The general antennas have reversibility, i.e., the same one antenna can be used as an emission antenna or as a receiving antenna. The same antenna is the same as the basic characteristic parameters of transmitting or reception. This is the mudity and theorem of the antenna.
The antenna is invented by Russian scientist Popov.
In 1888, the 29-year-old Bobov learned that the famous German physicist Hertz discovered the news of electromagnetic waves, this young scientist who had determined the promotion of the light said: "I use my life to install the electric light, for the vast Russia, just illuminates a small corner: if I can command magnetic waves, you can fly over the world! "
We know, communication, radar, navigation, broadcasting, TV and other radio devices are transmitted through radio waves, and they need radiation and reception of radio waves. In the radio, the device used to radiate and receive radio waves is referred to as antenna. The antenna provides the required coupling between the transmitter or receiver and the media that propagates radio waves. The antenna and transmitter, the receiver, is also an important part of the radio device.