Where is amplitude modulation used?

Answer 1

we have two types of signals namely the message signal and the carrier signal.

so if the amplitude of the carrier is varied in accordance with the instantaneous value of the message signal then it is known as the amplitude modulation.if we want to transmit our message signal to long distances we need to do modulation and hence amplitude modulation is done.

by amplitude modulation we generate side bands which consists of the part of the message which signal which is demodulated at the receiver to get back the original message signal

we are using this amplitude modulation in radio communication. It will work in the traffic also with out disturbances but frequency modulation didn't work without disturbances.

Answer 2

A.M. radio uses amplitude modulation. F.M. radio uses frequency modulation. There is no difference with respect to the energy of the signal. The difference in the radio in your car is that waves relying on amplitude get cut off by big structures like bridges. F.M. signals do not because their higher frequency allows them to have lower amplitude.

It is used in AM radio (amplitude modulation), as opposed to FM radio (which uses frequency modulation).

Answer 3

Amplitude modulation is not "so necessary".

If you want to use radio waves for communication, then it's not enough to just

generate a radio wave. In order to make it carry information, you have to change

the radio wave, according to some pattern that the person who receives it can understand.

The easiest way to do that is to turn the radio waves on and off, maybe with

some kind of pattern of longer and shorter 'on' and 'off' durations. That's a very

effective way to send information on radio waves, and it's exactly the whole idea

behind Morse Code. Unfortunately, it can't carry information fast or in large quantities.

Hand-keyed Morse Code is limited to maybe 250 characters per minute, corresponding

to something like 35 bits per second. You certainly can't send enough information

fast enough to make a sound or a picture, by switching the radio waves on and off.

The next easiest way to change the radio waves in a pattern that can carry

information, in large enough quantities and fast enough to represent a voice,

a musical instrument, or a TV picture, is amplitude modulation.

There are other methods. But amplitude modulation is the easiest. It was the

first method used to carry sounds over radio, and was the only method used

for commercial radio broadcasting until FM came along, in the late 40s or early 50s.

A:

I'll answer that it's very necessary -in radio comunication.

Analogue communication as distint from digital communication. has three ways of altering a radio wave Amplitude modulation, Frequency Modulation or Phase modulation.

Phase and frequency modulation are known for the fact that bandwidth (a very limited resource) is tied to the modulation index, so if you wish to move a lot of information you need a biger bandwidth.

amplitude modulation however does not require a larger bandwith no matter how fast the information changes.

When we get to complex modulation, such as QuAM, Phase and ampliture modultion are used together to crete very high sped data transfer in a limited bandwidth. with phase alone 8 bits can be sent at once, by adding amplitude modulation to the signal, this can be raised to 16, 32, 64 and 128 bit QuAM. so the return on investment in terms of throughput against banswidth justifies that AM is again the modulation of choice, and no longer the poor cousin to FM it once was.

Digital modulation has brought AM back into the essential category.

Answer 4

Amplitude modulation is very simple to generate compared to other modulation techniques.