How Exactly Wireless Communication Works?
Have you ever wondered how all your wireless communication works?
For example, have you ever wondered how antennas work?
Here, we attempt to explain to you the magical science behind electromagnetic waves and their various applications.
The Phenomenon of Long-Distance Communication
Have you ever turned to a radio station while driving in your car all around the city?
Have you ever wondered how you can talk to someone on the other side of the globe using a phone?
“All of these wonders were made possible because of antennas.”
What is an Antenna and how does wireless communication Works?
An antenna is a device composed of an ordinary conductor (primarily aluminium or copper), a readily available metal that can conduct electricity.
Electromagnetic waves are sent and received through conductive metal. This electromagnetic radiation is composed of locks that are not visible to the human eye.
They typically operate between 3 Kilohertz and 300 gigahertz and are the preferred mode of long-distance communication.
So, how does it work?
Short Answer, your antenna will capture these waves, and it will accurately output the “sound” within the wave.
Different Uses of Antennas
From radio to WiFi, antennas have different functions, but basically, they all work on the same basic principle. The transmitter will generate an electromagnetic wave when excited with electricity, and the receiver will capture these electromagnetic waves and convert them into electric pulses.
So, how does the music you listen to in your moving car come to you?
It starts with the heavy-duty radio transmitter located at the radio station. The transmitter’s electric signal coming from the microphone turns it into electromagnetic waves.
This current will travel to the antenna tower then the vibrating electrons, which are the negatively charged particles within an atom, rebounds around. As a result, electromagnetic radio waves are generated that are dissipated through space thousands of miles away.
The electrical equipment of the antennas is designed to broadcast the radio waves at a particular frequency, for instance, 90.5 megahertz.
Radio receivers then harness these waves. These radio receivers are antennas that are coupled to tuners. The tuners will then cycle through various frequencies of radio waves.
So, for example, if you tune the radio to capture 90.5 megahertz, the tuner will harness the incoming radio waves and send them to an amplifier that will enhance the electric signal coming and turn it into sound so you can listen to the music inside your car.
This idea of radio transmission and reception pretty much works the same as any other application of antennas, all the way from space communication to cell phones.
Nevertheless, the design of the antenna usually varies based on its intended purpose.
Here you will learn about how wireless communication works and the difference between AM (Amplitude Modulation) and FM (Frequency Modulation) wireless communication techniques.
| S.No. | Amplitude Modulation – AM | Frequency Modulation – FM |
| 1. | The first successful audio transmission was carried out in the mid-1870s | Developed in 1930 by Edwin Armstrong, in the United States |
| 2. | In AM, a radio wave known as the “carrier” or “carrier wave” is modulated in amplitude by the signal that is to be transmitted. | In FM, a radio wave known as the “carrier” or “carrier wave” is modulated in frequency by the signal to be transmitted. |
| 3. | The frequency range of AM radio varies from 535 to 1705 kHz | The frequency range of FM is 88 to 108 MHz in the higher spectrum |
| 4. | Bandwidth is less than FM or PM and doesn’t depend upon the modulation index. | The bandwidth requirement is greater and depends upon the modulating. |
| 5. | In AM radio broadcasting, if the modulating signal has a bandwidth of 15 kHz, then the bandwidth of an amplitude- The modulated signal is 30 kHz. | Let’s say, if the frequency deviation is 75kHz and the modulating signal frequency is 15kHz, the bandwidth required is 180kHz. |
| 6. | The number of sidebands is constant and equal to 2. | The number of sidebands having significant amplitude depends upon the modulation index |
| 7. | AM transmitters and receivers are less complex than FM and PM, but synchronization is needed in the case of SSBSC carriers. | FM (or PM) transmitters are more complex than AM because the variation of modulating signal has to be converted and detected from the corresponding variation in frequencies. |
| 8. | AM receivers are very less susceptible to noise because noise affects the amplitude, which is where information is stored in AM signals. | FM receivers are better immune to noise and can decrease noise by further deviation. |
| 9. | Power is wasted in transmitting the carrier. | All transmitted power is useful so that’s why FM is very efficient. |
| 10. | MW (Medium wave), SW (short wave) band broadcasting, video transmission in T.V. | Broadcasting FM, audio transmission on T.V. |
Despite their differences, AM (Amplitude modulation) and FM (Frequency modulation) work basically on the same principle.
The electromagnetic waves are first modulated, then afterwards, and the receiver picks them up to process and amplify them.
AM or amplitude modulation, as the name suggests, is a signal processing technique that carries the information on the amplitude of a wave to communicate. On the other hand, FM, or frequency modulation, carries the information on the frequency of radio waves to communicate.
The AM radio usually operates between 540 and 1600 kilohertz waves. Meanwhile, FM radio usually operates between 88.1 and 108.1 megahertz waves, carrying more information than the former.
Compared to an FM signal, the AM signal has a longer wavelength. Hence, it also requires a longer antenna. Also, an FM antenna is more straightforward and can be placed on top of the radio, while an AM antenna, which is copper wire wound around a magnet, is usually hidden.
Despite their magical abilities, antennas work on well-proven scientific principles. And their utility does not seem to end shortly. So keep your eyes peeled and expect more.
