What is Antenna and How does it work: Do you know what is this antenna (What is Antenna), How does this antenna work and what does it work for us? If all the questions are not answered then you should read this article from Antenna. Many of us will be people who have heard about the antenna, many will be seen, because some years ago we were often used to set TV antenna on the roof of TV for all TVs and if ever due to air If the antenna roams, do not ask, it would have been very disturbing, where one man would see the TV below, the other would go up and straighten it up. In fact what those days wereWhat is Antenna and How does it workDo you know what is this antenna (What is Antenna)?
How does this antenna work and what does it work for us? If all the questions are not answered then you should read this article from Antenna. Many of us will be people who have heard about the antenna, many will be seen, because some years ago we were often used to set TV antenna on the roof of TV for all TVs and if ever due to air If the antenna roams, do not ask, it would have been very disturbing, where one man would see the TV below, the other would go up and straighten it up. In fact what those days were
There is a lot of difference in the time of that time and now. Antenna now works on satellite TVs that have data received directly from the satellite. The antenna is mainly designed to receive signals. When a broadcasting station broadcasts a message, then with the help of antenna, it can be viewed on Television by receiving those signals.
To understand the full technology and to know about Antenna and its type, you will have to read this article fully. Often students are not able to get the right sources to understand the basics of antenna, so today I thought why you do not have an antenna for people and how it works so that you can easily understand the rest of the technology. Let’s start without delay.
What is Antenna:
The antenna is a type of device that is used to transmit and receive electromagnetic waves. Electromagnetic waves are often known as radio waves. Most antennas are resonant devices, which operate efficiently in a very narrow frequency band. To operate an antenna properly, it has to be tune (match) with the frequency band of the same radio system with which it is connected, if it does not happen, then both reception and transmission will be interrupted.
The antenna is used to radiate electromagnetic energy efficiently and that too only in the desired directions. Antennas behave like matching systems in one way, between the sources and space of electromagnetic energy. The main purpose of these antennas is to always optimize this match.
Let’s know briefly about some of the basic properties of the antenna:
- Field intensity is for all directions (according to the pattern of the antenna).
- Total power which is radiated when the antenna is excited by any current or voltage is called intensity.
- How much power radiate and the ratio of total power is called radiation efficiency.
- The input impedance of the antenna is always for maximum power transfer (matching).
- The bandwidth of antenna or range of frequencies on which all these properties depend on is almost constant.
All antennas are used to receive or radiate energy.
History of Antenna:
Well, the history of the Antenna is very old. Let’s know something about this. The first experiment was by Faraday in 1830, in which he had coupling electricity and magnetism, and in which he had shown that there was a definite relationship between them.
For this, he slid a magnet on the coil of wire variables which was attached to the Galvanometer. When he moved the magnet, he found that a time-varying magnetic field was generated, and with Maxwell equations, it also came out that time-varying electric field also arises.
In this coil worked like a loop antenna and received that electromagnetic radiation, which was detected by the galvanometer – it is completely an antenna’s work.
The interesting thing is that at that time no one knew about electromagnetic waves.
Heinrich Hertz developed a wireless communication system in which he forced an electrical spark to be between the gap of the dipole antenna. He used a loop antenna as a receiver and similarly observed the disturbance. This thing happened in the 188th in 1886. In 1901 Marconi sent all information about Atlantic. They attach lots of vertical wires to the ground at the end of a transmitting antenna.
In 1906 Columbia University created such an experimental Wireless Station where they used a transmitting aerial cage. This cage was made from wires and was suspended in the air.
After that many such experiments have been done and according to the dates I have written the following: –
- Yagi – Uda Antenna, 1920
- Horn Antenna, 1939
- Antenna Arrays, 1940
- Parabolic Reflectors, in the late 1940s
- Patch Antennas, 1970
- PIFA, 1980
After this, the series continued and there were many changes in the antennas and now the only antenna we are using is only after learning from all these antennas we have come to know.
Types of Antenna:
Although there are many types of antennas, they are mainly divided into three broad categories: omnidirectional, directional, and semi-directional.
- Where Omni-directional antennas propagate in all directions.
- The second is the semi-directional antennas that propagate in a constricted fashion, and they are defined in a specific angle.
- The third is the Directional antennas in which there is a narrow “beam” which allows highly directional propagation; There are those familiar types in this parabolic and Yagi. All of these are unique features and applications.
Dipole Antennas or Rubber Ducky Antenna:
These Dipole antennas are a very common type of antenna and are also omnidirectional, they propagate in a horizontal plane in radio frequency (RF) energy 360 degrees. These devices are designed to be some kind of resonant which is applied to the frequency of half or quarter wavelength which is applied to it. This antenna is very simple, in which two pieces of wire are cut, proper length and encapsulated.
This configuration is commonly referred to as “rubber ducky” antenna. This dipole is used in many enterprises and small office, home office (SOHO) Wi-Fi deployments.
Directional and semi-directional antennas mainly focus on radiated power to beams, in which they add gain to a significant amount of process. Properties of the antenna are also reciprocal. The characteristics of transmitting antennae such as impedance and gain are applicable, above a receiving antenna. That is why the same antenna is used for both sending and receiving.
This highly directional parabolic antenna is used to amplify gain weak signals; This is the reason why this kind of antenna is used for frequent use of long-distance links.
Patch Antenna or Microstrip Antenna:
A patch antenna is a type of semi-directional radiator in which a flat metal strip is mounted above the ground plane. The radiation emitted from the back of the antenna is effectively cut off, with the help of ground plane, so that its forward directionality can be increased. This type of antenna is also called a microstrip antenna. It is typically of rectangular shape and it is enclosed in a plastic enclosure.
This type of antenna can be manufactured in a standard printed circuit board methods. Patch antennas are mostly used according to semi-directionals; There is a beamwidth of a patch antenna between 30 to 180 degrees and a typical gain is 9 dB.
Sector antennas are also another type of semi-directional antenna. Sector antennas provide a radiation pattern of pie-shaped (sector) and they are usually installed in a sectorized array. Their beamwidth is between 60 to 180 degrees, in which 120 degrees is very typical. In a sectorized array, the antennas are back-to-back mounted so that they can provide full 360-degree coverage. Sector antennas are used extensively in cellular communication.
A very commonly used directional antenna is Yagi-Uda Array, it is also known as Yagi. It was invented by Shintaro Uda and his colleague, Hidetsugu Yagi, in 1926. A Yagi Antenna uses lots of elements to form a directional array. A single driven element, typically a dipole, propagates RF energy; The elements that are used are immediately driven in the front of the element and in the rear of which it can re-radiate the RF energy, in-phase and out of phase, as well as to enable and retain signals. These elements are called parasitic elements.
Those who come in the back of the element driven element are called reflectors, those elements which come in front of the elements driven are called directors. The beamwidths of Yagi antennas occur in 30 to 80 degrees and they provide well over 10 dBi passive gain.
Parabolic or Dish Antenna:
Parabolic, or dish, antennas are a very familiar type of directional antenna. A parabola is an asymmetric curve; A parabolic reflector is a surface that can provide curves throughout a 360-degree rotation – this dish is technically called a paraboloid. A parabolic reflector has a high degree of directivity and has the ability to focus RF energy in a beam, such as in a flashlight.
Parabolic antennas have very narrow beamwidth, usually, it does not exceed 25 degrees. The gain depends on the diameter and frequency; As in 2.4 GHz, a 1-meter dish provides about 26 dBi gain, while a 10-meter antenna provides the gain of 46 dBi in the same frequency. This antenna is “fed” with a half-wave dipole antenna or a feed horn. Parabolic antennas are used for long-distance communication links between buildings or large geographic areas. Very large parabolic antennas are used for radio astronomy and these can provide gain 10 million or about 70 dBi.
A variation of Dish is called grid antenna. Because a parabolic reflector can easily heal from its place in moderate wind conditions and their alignment becomes deformed. Therefore, to prevent this problem the reflector is perforated in a grid. The spacing frequency of the grid elements is dependent; And this is inversely proportional to frequency. Its gain and beamwidth are the same as the parabolic antenna.
How Antenna Works:
You will love to know how Antenna works. Suppose that you are in a radio station in charge and you want to transmit your program to the external world How are you going to do this? Let’s know For this, you probably use microphones that capture your voice and transform them into electrical energy. You can take that power and after that, you can take it to send some tall metal antenna. Where this antenna will boost it very often, it will be able to travel far enough, the more you boost the signal, the more distance you can find. Since these electrons (tiny particles which are within an atom), in the electric current, back and forth motion along with the antenna, in this, it creates invisible electromagnetic radiation which occurs in the form of radio waves.
These waves, which are partly electric and partly magnetic, travel by the speed of light and carry it along with the radio program. What happens when a person starts the radio in his house, which is kilometers away from that station? These are the radio waves of which you have sent through the metal antenna and which forces the electrons to wiggle back and forth. It generates an electric current – they do electronic signals of the electronic receiver in your house and sign the signal again in the sound that you have heard.
The designs of transmitter and receiver antennas are very similar. Where antennas are used to send signals, they are very large and heavy on the radio or TV station. They are receivers like you and the ones we use in Radion channels or tv channels. Are smaller than the senders. But both works is the same.
Waves are not always zapped when they are sent from the transmitter to the receiver in the air. It depends on the types of waves we are sending, how their frequency is, how far we want to send it, and what we want to do with these waves, etc. – mainly three different types of ways The waves that travel through are: –
- The first is “Line of Sight”, it was brought to Istanbul many years ago. In this, the waves were sent in a single direction such as a beam of light. They used to be used in old-fashioned long-distance telephone networks, in which microwaves were used to carry calls, between large high communication towers. But the use of fiber-optic cables stopped the technology completely.
- Then comes the Ground Wave. These waves can travel around the curvature of Earth’s. AM (medium-wave) radio travels like this for short-to-moderate distances. This explains why we have heard radio signals even when we do not even see any radio transmitter in front of our eyes.
- It comes in the end “Ionospheric Wave” In it, the waves are shot in the sky (sent), and they Reflecting from the ionosphere bounces off, and then reaches the ground again. These ionospheres are an electrically charged part of Earth’s in the upper atmosphere which reflects the waves. But they work better in the night because at that time the ionosphere reflects all the waves, they even absorb some waves during the day. Due to this property of the Ionosphere, it is also called Sky Mirror and it can send radio waves to very long distances.
What are some of the important properties of antennas?
Well, there are many features of Antenna but here we will talk about some important features only.
Directionality: Dipoles are very directional: so they can pick only those signals that come in right angles on their side. Therefore it is very necessary to mount a TV antenna properly in your house, that too in the right way and in the correct direction. It is believed that the highly directional antennas look a bit awkward and it is also difficult to install them, but if they are properly aligned, then there are very few interferences and extraordinary signals do not occur.
Gain: The gain of an antenna means that how much he can boost the signal. Many times you might have seen that TVs often catch some bad signals without any antenna itself. This is because it’s metal case and other components work as a basic antenna, and do not focus on any particular direction, and therefore they catch the near signals. Using a proper directional antenna, you can get better gain. Gain is measured in decibels (dB). One thing to understand today is that the more profit, the better the reception will be. So outdoor antenna works better than in the indoor because they have more gain.
Bandwidth: The bandwidth of an antenna is its range of frequencies (or wavelengths, if you prefer it) on which it works effectively. The broader is the bandwidth, the greater is its range, and by which it can pick up the number of different radio waves. This is more helpful for television, where you can pick up many channels. There is a narrow bandwidth in Mobile, Radio.
Aperture: Aperture is also called the effective aperture of the antenna and it actively participates in the transmission and reception of electromagnetic waves. Those who are received by power antenna are all connected in one place with a collective area. The corresponding collected area itself is called the effective aperture of an antenna.
Polarization: An electromagnetic wave which was launched by an antenna can be polarized to him vertically and horizontally in both directions. If a wave is polarized in a vertical direction, then the E vector is vertical and it requires a vertical antenna. If vector E is horizontal, then it requires a horizontal antenna to launch. Occasionally circular polarization is also used, it is a combination of both horizontal and vertical ways.
Effective Length: Effective length A parameter is antennas which characterize the efficiency of the antenna to transmit and receive electromagnetic waves. Effective length is defined for both transmitting and receiving antennas. In the EMF receiver input, the ratio of the intense electric field which is generated in the antenna is called the ratio of receivers’ effective length. The effective length of the transmitter is called in which the conductor’s free space length and current distribution across its length when generating the same field intensity in any direction of radiation.
Effective Length = (Area under non-uniform current distrbution) / (Area under uniform current distribution)
Polar diagram: This is a very important property in an antenna called radiation pattern or polar diagram. In the case of transmitting antenna, there is a plot which talks about the strength of the power field which is radiated by the antenna in various angular directions. A plot is obtained for both vertical and horizontal planes – and these are called vertical and horizontal patterns, respectively.
Advantages of Antennas according to their type:
Let’s know about the advantages of antennas. Well, these advantages depend on the types of antennas. Let’s know
- Dipole Antenna: They are cheap and exhibit good gains.
- Whip Antenna: These tend to deliver better performance than being of small size, compared to the dipole antenna.
- Loop Antenna: These are cheap and are not easily de-tuned with hand movements.
- Spiral Antenna: Their size is less than the whip antenna. They are used for wideband applications.
- Helical Antenna: These are very directive antenna and they provide good amounts of gain.
- Microstrip Antenna: These are very simple and a chip antenna. They are used in the smartphone because their structure is very thin.
- Ceramic Antenna: These are of very small size and they are not affected more than the environment. They use different components.
- Slot Antenna: Their design is very simple and they are of small size. These are more robust nature.
DisAdvantages of Antennas according to their type:
Let’s know about the disadvantages of Antennas. Well, these disadvantages depend on the types of antennas. Let’s know
- Dipole Antenna: They exhibit a large size in lower frequency.
- Whip Antenna: These are very costly. These require a better ground plane to get good performance.
- Loop Antenna: They have very poor gains, they are difficult to tune and they are very narrowband.
- Spiral Antenna: Its major disadvantage is that it is very difficult to feed these types of antenna.
- Helical Antenna: These are very bulky in size. They can be easily de-tuned from nearby objects. So there are more disturbances in it.
- Microstrip Antenna: These are the very large size in low frequency. PCB design can affect their performance and tuning. It is very difficult to design for less than 433 MHz.
- Ceramic Antenna: These are of the very high cost. Also, they deliver only medium performance. These are the matching function of PCB size and ground plane shape.
- Slot Antenna: Their size is very large in the lower frequency and therefore they are very difficult to design for lower frequencies, which are less than 433 MHz.
What are the applications of Antenna:
There are many different applications of antennas which differ according to the type of antenna and their application is different. Let’s know about some important applications.
They are mainly used for radio broadcasting.
• Navigational systems are also used by boat sailors.
• For radio transmission and reception.
• It is also used to look directly at GPS.
• For satellite communication.
• They are also used for radio frequency identification as well.
What is the intensity of Antennas:
Although antennas are generally considered to be an antiquated technology, telecommunications companies are always in search of how they can innovate more of these antennas so that they can be used in the next generation of electronics. Talk about now, product engineers are still using 3D printing and refined manufacturing techniques to make the antennas smaller, lighter, and more powerful than ever before.
Cell phone companies are working on bringing forward 5G technology, which is going to bring a big revolution in the times of small cell towers. In the same way, we can get to see more of the technologies which can be used to change the whole body of Antennas. But one thing is that regardless of how many innovations are done, the traditional cell phone towers and big antennas have been a very important role for us and our communication system, and it will be in the coming time too.
Finally, I hope guys you understand “What is Antenna and How does it work?” especially helpful. If you enjoyed this post, please leave a comment below and share it with your friends and followers on Facebook and Twitter.