Antenna

Antenna
An antenna is a device used to transmit and receive electromagnetic signals. It consists of an active element, usually made of metal, mounted on a conductive surface that serves as the radiating or receiving element. Antennas are most commonly used in radio communication systems such as television broadcast, satellite communication, cellular phone networks and wireless internet access. They can also be used in radar systems for detecting objects at long distances.

The design of antennas depends on their particular application and the frequency band they will be operating in. The two main types of antennas are directional and omnidirectional antennas. Directional antennas focus the energy emitted by them into a single direction while omnidirectional antennas disperse it equally in all directions around them. These two types differ greatly in their performance characteristics such as gain, directivity pattern and radiation efficiency among others.

The shape and size of an antenna also affects its performance characteristics significantly; this is why different kinds of antenna designs have been developed depending upon their intended use: from simple dipoles to sophisticated parabolic reflector dishes with multiple feed points for high-gain applications at certain frequencies ranges like satellite communications or terrestrial broadcasting services like TV or FM radio stations .

A special type of antenna is called array which consist several individual elements placed close together so that they create what is known as ‘coherent radiation’ allowing increased control over phase shifts between each individual element thus leading to improved gains compared to single-element designs without compromising too much directivity patterns or other important parameters essential for successful transmission/reception operations . In addition arrays can be configured using various methods ranging from linear (collinear) layouts where all elements share the same axis up to complex circular configurations necessary when extreme beam forming capabilities are required due to environmental constraints like obstacles (buildings, trees etc).

In conclusion it is clear that there exists a wide variety of antenna designs suited for many different applications requiring specific features according to purpose served but all based on fundamental principles established during past centuries making possible today’s impressive development within telecommunications industry achieving unimaginable performances just few decades ago .