What is Antenna and how it works-
Do you know what this antenna is, 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. There will be many people among us who have heard about the antenna, many will also be seen, because some years ago we were often used to induce 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. Really what those days were
There has been a lot of difference in the time and time of that time. Antenna now works on satellite TVs, which have data reception directly from satellite. 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 full. 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 antenna for people in Hindi and how it works in English so that you can easily understand the rest of the technology Ho. Let's start without delay.
What is antenna-
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 very narrow frequency band. To operate an antenna properly, it must have a tune (match) with the frequency band of the same radion system with which it is connected, if it does not happen, both reception and transmission will be interrupted.
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 souces 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 antenna:
1- Field intensity is for all directions (according to pattern of antenna).
2- Total power which is radiate when antenna is excited by any current or voltage is called intensity.
3- How much power radiate and the ratio of total power is called radiation efficiency.
4- The input impedance of antenna is always for maximum power transfer (matching).
5- The bandwidth of antenna or range of frequencies on which all these properties depend on are almost constant.
All antennas are used to obtain or radiate energy.
History of Antennae-
Well the history of Antenna is very old. Let's know something about this. The first experiment was by Faraday in 1830, in which he was 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 to the magnet, he found that one time differenting magnetic field was generated, as well as from 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 1882, in 1886. In the year 1901 Marconi sent all information of 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 air.
After that many experiments have been performed and according to the dates, I have written the following: -
1. Yagi - Uda Antenna, 1920
2 . Horn Antenna, 1939
3. Antenna Arrays, 1940
4. Parabolic Reflectors, in the late 1940s
5. Patch Antennas, 1970
6. PIFA, 1980
After this, the series continued and there were many such changes in the antennas and now we are using the antenna which we have learned after learning from all these antennas.
Types of antenna
Although there are many types of antennas, they are mainly divided into three broad categories: omni-directional, directional, and semi-directional.
1. Where Omni-directional antennas propagate in all directions.
2. The second is the semi-directional antennas that propagate in a constricted fashion, and they are defined in a specific angle.
3. The third is the Directional antennas in which there is a narrow "beam" which allows highly directional propagation; There are those familiar types in it, parabolic and yagi. All of these are unique features and applications.
Dipole Antennas or Rubber Ducky Antenna-
These Dipole antennas are very common type of antenna and are also omni-directional, they propagate in horizontal plane in radio frequency (RF) energy 360 degrees. These devices are designed to be some kind of resonant which is applied on 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 enterprise and small office, home office (SOHO) Wi-Fi deployments.
Directional Antenna-
Directional and semi-directional antennas mainly focus on radiating power to beams in narrow beams, so that they add a significant amount of gain to the process. Properties of antenna are also reciprocal. The characteristics of transmitting antenna such as impedance and gain are applicable, above the 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 why this type 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 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 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 Antenna-
Sector antennas are also another type of semi-directional antenna. Sector antennas provides 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, antennas are back-to-back mounted so that they can provide full 360-degree coverage. Sector antennas are used extensively in cellular communication.
Yagi Antenna-
A very commonly used directional antenna is Yagi-Uda Array, it is also known as Yagi. It was invented 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 very familiar type of directional antenna. A parabola is a symmetric curve; A parabolic reflector is a surface that can provide curve 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 not more than 25 degrees. 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 large geographic areas. Very large parabolic antennas are used for radio astronomy and these can provide gain 10 million or about 70 dBi.
Grid Antenna-
A variation of the Dish is called grid antenna. Because a parabolic reflector can easily be heated from its place even 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 frequency. Its gain and beamwidth are the same as parabolic antenna.
How Antenna Works -
You will love to know how Antenna works. Suppose you are in a radio station incharge 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 convert them into electrical energy. You can take that power and after that you can take it to send some long metal antenna. Where this antenna will boost it very often, which will allow it to travel far enough, the more you boost this signal, the more distance it will be able to fix. Since these electrons (tiny particles which are within atom) in the electric current, back and forth move along with antenna, in this, it produces an invisible electromagnetic radiation that 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 metal antenna and which forces the electrons to wiggle back and forth. It generates an electric current - these signals are electronic components of the radio in your home and you re-sign the signal that you have heard.
The designs of transmitter and receiver antennas are very similar. Where antennas are used to send signals, they are very big and heavy in the radio or TV station, receivers such as you and the ones we use in Radion channels or TV channels to see these very Are smaller than the senders. But both work are the same.
Waves are not always zap when they are transmitted 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 are: -
1. 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 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.
2. Then happens the Ground Wave. These waves can travel around the curvature of the 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 before our eyes.
3. Finally comes the "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 ionosphere are an electrically charged part, in the Earth's upper atmosphere, which reflect 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 Ionosphere, it is also called Sky Mirror and it can send radio waves to very long distances.
What are some 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 interference and there are no extra cues.
Gain: - The gain of an antenna means that how much he can boost the signal. Many times you might have seen that the TVs often catch some bad signals without any antenna itself. This is because its metal case and other components work like a basic antenna, and do not focus on any specific direction, and so they catch the near signals. By 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 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 more broader is the bandwidth, the greater is its range, and by which it can pick up as much different radio waves. This is more helpful for television, where you can pick up many channels. There is a narrow bandwith in Mobile, Radio.
Aperture: Aperture is also called the effective aperture of the antenna and it actively participates in 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 any 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 that characterizes the efficiency of 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 intensity 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 generates 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 radiate by 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 good performance even when being small size compared to 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 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 much affected by 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 diadvantages of Antennas. Well these disadvantages depend on the types of antennas. Let's know
➨ Dipole Antenna: They exhibit large size in lower frequency.
➨ Whip Antenna: These are very costly. These require 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. Therefore there are more disturbances in it.
➨ Microstrip Antenna: These are 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 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 high 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 that differ according to the type of antenna and their application is also 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 see direction in the GPS.
For satellite communication
They are also used for radio frequency identification.
What is the intensity of antennas: -
Although antennas are generally considered an antiquated technology, but 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. Now, talk about 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 entire body of Antennas. But one thing is that regardless of how many innovations are done, traditional cell phone towers and large antennas have been a very important role for us and our communication system, and it will be in the coming time too.
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post by- www.thetechnicalhouse.com
Do you know what this antenna is, 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. There will be many people among us who have heard about the antenna, many will also be seen, because some years ago we were often used to induce 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. Really what those days were
There has been a lot of difference in the time and time of that time. Antenna now works on satellite TVs, which have data reception directly from satellite. 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 full. 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 antenna for people in Hindi and how it works in English so that you can easily understand the rest of the technology Ho. Let's start without delay.
What is antenna-
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 very narrow frequency band. To operate an antenna properly, it must have a tune (match) with the frequency band of the same radion system with which it is connected, if it does not happen, both reception and transmission will be interrupted.
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 souces 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 antenna:
1- Field intensity is for all directions (according to pattern of antenna).
2- Total power which is radiate when antenna is excited by any current or voltage is called intensity.
3- How much power radiate and the ratio of total power is called radiation efficiency.
4- The input impedance of antenna is always for maximum power transfer (matching).
5- The bandwidth of antenna or range of frequencies on which all these properties depend on are almost constant.
All antennas are used to obtain or radiate energy.
History of Antennae-
Well the history of Antenna is very old. Let's know something about this. The first experiment was by Faraday in 1830, in which he was 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 to the magnet, he found that one time differenting magnetic field was generated, as well as from 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 1882, in 1886. In the year 1901 Marconi sent all information of 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 air.
After that many experiments have been performed and according to the dates, I have written the following: -
1. Yagi - Uda Antenna, 1920
2 . Horn Antenna, 1939
3. Antenna Arrays, 1940
4. Parabolic Reflectors, in the late 1940s
5. Patch Antennas, 1970
6. PIFA, 1980
After this, the series continued and there were many such changes in the antennas and now we are using the antenna which we have learned after learning from all these antennas.
Types of antenna
Although there are many types of antennas, they are mainly divided into three broad categories: omni-directional, directional, and semi-directional.
1. Where Omni-directional antennas propagate in all directions.
2. The second is the semi-directional antennas that propagate in a constricted fashion, and they are defined in a specific angle.
3. The third is the Directional antennas in which there is a narrow "beam" which allows highly directional propagation; There are those familiar types in it, parabolic and yagi. All of these are unique features and applications.
Dipole Antennas or Rubber Ducky Antenna-
These Dipole antennas are very common type of antenna and are also omni-directional, they propagate in horizontal plane in radio frequency (RF) energy 360 degrees. These devices are designed to be some kind of resonant which is applied on 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 enterprise and small office, home office (SOHO) Wi-Fi deployments.
Directional Antenna-
Directional and semi-directional antennas mainly focus on radiating power to beams in narrow beams, so that they add a significant amount of gain to the process. Properties of antenna are also reciprocal. The characteristics of transmitting antenna such as impedance and gain are applicable, above the 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 why this type 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 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 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 Antenna-
Sector antennas are also another type of semi-directional antenna. Sector antennas provides 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, antennas are back-to-back mounted so that they can provide full 360-degree coverage. Sector antennas are used extensively in cellular communication.
Yagi Antenna-
A very commonly used directional antenna is Yagi-Uda Array, it is also known as Yagi. It was invented 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 very familiar type of directional antenna. A parabola is a symmetric curve; A parabolic reflector is a surface that can provide curve 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 not more than 25 degrees. 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 large geographic areas. Very large parabolic antennas are used for radio astronomy and these can provide gain 10 million or about 70 dBi.
Grid Antenna-
A variation of the Dish is called grid antenna. Because a parabolic reflector can easily be heated from its place even 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 frequency. Its gain and beamwidth are the same as parabolic antenna.
How Antenna Works -
You will love to know how Antenna works. Suppose you are in a radio station incharge 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 convert them into electrical energy. You can take that power and after that you can take it to send some long metal antenna. Where this antenna will boost it very often, which will allow it to travel far enough, the more you boost this signal, the more distance it will be able to fix. Since these electrons (tiny particles which are within atom) in the electric current, back and forth move along with antenna, in this, it produces an invisible electromagnetic radiation that 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 metal antenna and which forces the electrons to wiggle back and forth. It generates an electric current - these signals are electronic components of the radio in your home and you re-sign the signal that you have heard.
The designs of transmitter and receiver antennas are very similar. Where antennas are used to send signals, they are very big and heavy in the radio or TV station, receivers such as you and the ones we use in Radion channels or TV channels to see these very Are smaller than the senders. But both work are the same.
Waves are not always zap when they are transmitted 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 are: -
1. 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 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.
2. Then happens the Ground Wave. These waves can travel around the curvature of the 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 before our eyes.
3. Finally comes the "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 ionosphere are an electrically charged part, in the Earth's upper atmosphere, which reflect 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 Ionosphere, it is also called Sky Mirror and it can send radio waves to very long distances.
What are some 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 interference and there are no extra cues.
Gain: - The gain of an antenna means that how much he can boost the signal. Many times you might have seen that the TVs often catch some bad signals without any antenna itself. This is because its metal case and other components work like a basic antenna, and do not focus on any specific direction, and so they catch the near signals. By 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 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 more broader is the bandwidth, the greater is its range, and by which it can pick up as much different radio waves. This is more helpful for television, where you can pick up many channels. There is a narrow bandwith in Mobile, Radio.
Aperture: Aperture is also called the effective aperture of the antenna and it actively participates in 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 any 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 that characterizes the efficiency of 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 intensity 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 generates 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 radiate by 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 good performance even when being small size compared to 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 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 much affected by 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 diadvantages of Antennas. Well these disadvantages depend on the types of antennas. Let's know
➨ Dipole Antenna: They exhibit large size in lower frequency.
➨ Whip Antenna: These are very costly. These require 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. Therefore there are more disturbances in it.
➨ Microstrip Antenna: These are 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 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 high 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 that differ according to the type of antenna and their application is also 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 see direction in the GPS.
For satellite communication
They are also used for radio frequency identification.
What is the intensity of antennas: -
Although antennas are generally considered an antiquated technology, but 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. Now, talk about 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 entire body of Antennas. But one thing is that regardless of how many innovations are done, traditional cell phone towers and large antennas have been a very important role for us and our communication system, and it will be in the coming time too.
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