plz explain me about frequency modulation in simple language?

Answer 1

Modulation is information in the form of variable frequency. A carrier wave is a wave with steady single frequency. Now when you superimpose the information variable frequency on top of the carrier wave frequency you modulate the carrier wave and it becomes a wave with different frequencies and that is modulation i.e. adding and subtracting frequencies to and from the carrier frequency.

Answer 2

Purpose of Modulation

Suppose if i am sending an information through a channel like copper line or air medium, the signal must have sufficient energy to reach the destination.

For example if we shout loudly , it may be audible at the most 100 meters. But what if u want to convey your message to a destination that is 100 Km far away..?

Answer is Modulation

So u need to increase the energy of the information signal that u are sending.
One way to increase the energy of the information signal is to increase the frequency of your message. Since the speech frequency is almost limited upto 4000 Hz (4KHz) it cant have sufficient energy. So we need to increase the energy

The relation is given by
E=hv
Where E = Energy , h=Planck's constant and v=frequency.

So by increasing Frequency, Energy of the signal can be increased so that it can travel long distances.

This is achieved by combining your message with a carrier signal having High frequency sufficient to travel the distance.

Some ways to do this are
1. Amplitude Modulation (AM)
2.Frequency Modulation (FM)

In AM the amplitude of the high frequency carrier is varied in accordance with the information signal

In FM the frequency of the high frequency Carrier is varied in accordance with the information signal. Means the Center Frequency (which is sufficiently high) oscillated according to the message.

Thus on the receiving side the receiver is tuned to the center frequency and the variations of the incoming signal about this center frequency convey the information

Answer 3

Advantage of modulation:
As the smaller frequency is not able to travel long distance without distortion.. we add higher frequencies

And the length of antenna can be small

Now for frequency modulation.. we modify the frequency of the carrier signal according to the amplitude of the modulating signal.

Eg. if the AC signa is having an equation

A1=Ac cos A
and the modulation signal is A2= Ac cos B

then the resulting signal becomes Ac cos (A+B)

Note.. : The amplitude of the carrier is not affected.

Answer 4

Frequency modulation means that the frequency of the carrier wave is changed in response to the amplitude of the modulating signal.

HTH ☺

Doug