Radio is the mode of communication by the transfer of signals from the sender to the receiver. It plays an important role in our society and considered as the best tool for government, business, and personal matters.
We can easily say that radio plays an essential role in connecting people from one part of the world to another as it acts as a connective bridge. Along with the importance of communication, it is also essential to know that how do radio waves work?
We all are familiar with the importance of radio. AM/FM is just magic. You switch it on and listen to all the updates of each field that includes music voice and any other audio entertainment. You can easily be entertained from hundreds and thousands of miles away, depending on the wavelength.
How radio works:
Radio works by transmitting and receiving electromagnetic waves. The signals are electric current that quickly moves. The transmitter radiates these signals toward the antenna. The receiver picks up that field and translates it into the sound that is heard from the radio.
In Amplitude modulation, the strength of the radio is changed, whereas in Frequency modulation speed of the signals is changed. When you dial any number, it indicates the frequency of the messages.
Frequency:
The signals use the specific frequency, and it directly depends on how quickly the waves move up and down. The rate of the waves is measured by Hertz, which is the measurement unit of the wave cycle per second.
AM frequency is measured in kilohertz, and FM frequency is measured in megahertz. The range of signals is affected by station power.
What Are Radio Waves?
Both Amplitude Modulation and Frequency Modulation radio programs are transmitted in the air through waves. They are the part of the full range of electromagnetic waves like gamma rays, x-rays, visible right, microwaves, infrared, and ultraviolet rays.
Electromagnetic waves are present everywhere with a wide range of frequencies that our eyes are not sensitive to. These waves are present in the form of visible light or ultraviolet.
If we talk about electromagnetic waves, these waves are generated by the alternating current that is electrical power use to rum every appliance. Alternating current operates at different volts, most common is 120 volts at 60Hz. That means the current changes its direction in the wire 60 times in a second.
Some of the electricity also escapes the wire that is transmitted in the air. It is essential to know that the higher frequency has more ability to produce energy.
The Concept of Modulation:
Signals that transmit the information are modulated first based on AM and FM modulation. This is the term from which AM and FM are originated as AM means Amplitude Modulation and FM means Frequency Modulation.
The word modulation is also used for change that means the electromagnetic waves are modulated to be useful in radio transmission.
You can easily under the term modulation by a simple example. A piece of paper is useless until it will be modulated in some meaningful way. You have to draw or write something to transmit the user information.
In this way, the electromagnetic radiation must be modulated to transmit the desired information.
AM Radio Broadcasts:
AM radio uses amplitude modulation that is considered as the purest form of radio broadcast. It has excellent capability to transmit information over great distances. However, these signals are more susceptible to noise and static interference.
FM Radio Broadcasts:
FM radio used frequency modulation, and the frequency is unmodulated. It means that there is no useful information contained and it is also known as stereo. FM signals are more susceptible to interference and noise that any physical barrier can easily limit them.
Any physical barrier directly affects the overall reception. It is the reason that you can easily pick up individual stations more efficiently.