How Horn Antenna and Broadband Antenna works
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serves the same function for electromagnetic waves that an acoustical horn does for sound waves in a musical instrument such as a trumpet. It provides a gradual transition structure to match the impedance of a tube to the impedance of free space, enabling the waves from the tube to radiate efficiently into space.
If a simple open-ended waveguide is used as an antenna, without the horn antenna, the sudden end of the conductive walls causes an abrupt impedance change at the aperture, from the wave impedance in the waveguide to the impedance of free space, (about 377 ohms). When radio waves travelling through the waveguide hit the opening, this impedance-step reflects a significant fraction of the wave energy back down the guide toward the source, so that not all of the power is radiated. This is similar to the reflection at an open-ended transmission line or a boundary between optical mediums with a low and high index of refraction, like at a glass surface. The reflected waves cause standing waves in the waveguide, increasing the SWR, wasting energy and possibly overheating the transmitter. In addition, the small aperture of the waveguide (less than one wavelength) causes significant diffraction of the waves issuing from it, resulting in a wide radiation pattern without much directivity.
To improve these poor characteristics, the ends of the waveguide are flared out to form a horn. The taper of the horn changes the impedance gradually along the horn's length. This acts like an impedance matching transformer, allowing most of the wave energy to radiate out the end of the horn into space, with minimal reflection. The taper functions similarly to a tapered transmission line, or an optical medium with a smoothly varying refractive index. In addition, the wide aperture of the horn projects the waves in a narrow beam
The horn antenna that gives minimum reflected power is an exponential taper. Exponential horn antenna are used in special applications that require minimum signal loss, such as satellite antennas and radio telescopes. However conical and pyramidal horns are most widely used, because they have straight sides and are easier to design and fabricate.
How Wireless Broadband Antenna Works?
Working of the wireless
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really plays an important role in maintaining the working of the wireless networking device. Working of the wireless broadband antenna depends on different steps, like other workings, working of wireless broadband antenna also starts with the setting. First of all two antennas are placed on different places to perform the task of the transmission and the receiving of data in the form of radio waves. When both places are ready to do the communication through wireless broadband antenna devices then it is important to generate the antenna for transmission. Some amount of current is required to generate the wireless antenna, when the current passes through the antenna it introduces the magnetic power at a given frequency of radio waves that are used for the data transmission. When we do the change the amount of current in the antenna then there is change happens in the frequency of the radio waves, and then these radio waves moves out from the antenna in the specific direction and receives on the other end on the receiving antenna.
