Modulation and Demodulation - Definition, Advantages, Types, FAQs

What is Modulation?

Modulation definition and Modulation meaning/Modulator meaning: It is the method of converting some given data into radio waves by adding certain information to a carrier signal and it does not affect the original properties and even the characteristics of the transmitted message signal.
If the characteristics of the message signal get changed, then the message contained in it also gets changed or even altered.
Hence, it is essential to take precautions regarding transmitted message signals.
A high-frequency signal may travel up to a larger distance and the chances of getting affected by external disturbances are less.
We often take help from such a high-frequency signal, also called allowed. →Improving as a carrier signal for transmitting the message signal. This explained process is known as Modulation.

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Advantages of Modulation

The time before the concept of modulation, the antenna which is used for transmission had to be very large. Hence, the range of communication used to get very limited as the wave was unable to travel to a large distance.

The advantages of modulation are as follows:

1.The size of the antenna decreases

2.There is no space for signal mixing

3.Bandwidth adjustments are allowed

4.Improving the quality of reception

Difference Between Modulation and Demodulation

Modulation: It is often defined as the process of mixing a signal with a sinusoid to produce a new signal.

The new signal has some new benefits over an old (unchanged) signal.

Specifically, the combination of a low-frequency signal with a high-frequency network signal is known as Modulation.

Demodulation: It is the process of issuing the first signal modulation that transmits information that carries information from a network company wave.

Amplitude Modulation

It is a modulation technique that is most commonly used to transmit certain information with the help of radio wave

If the angle of the carrier wave gets changed by the instantaneous amplitude of the modulating signal, then it is called an Angle Modulation.

The angle modulation is divided as frequency modulation and phase modulation.

1. Frequency Modulation

If the frequency of the given carrier wave gets changed,by the instantaneous value of the modulating signal,then it is called a Frequency Modulation.

2. Phase Modulation

If the phase of the given carrier wave gets changed by the instantaneous value of the modulating signal, then it is called a Phase Modulation.

Different Types of Modulation

There are various different types of modulations that are based upon the modulation techniques used.

Modulation is usually of two different types; they are as follows:.

1.continuous-wave modulation

2. Pulse modulation

1. Continuous-wave modulation:.

Here a high-frequency sine wave is usually used as a carrier wave.

2. Pulse modulation:.

Here a periodic sequence of some rectangular pulses is used as a carrier wave.

What is the need for modulation?

When a transfer takes place over free space, the antennae emit a signal and the recipient accepts you. For proper operation, the antenna needs to be at the maximum length of the given transmitted signal.

L = λ = uϑ = (3 ∗ 10⁸) ϑHz

Speech frequency ranges from 20 Hz to 20 kHz. So if you think this is a frequency of 20 kHz and is released to the receiver via a free local channel.

Length Of = 3 ∗ 10⁸/20 ∗ 10³ = 15000m = 15km

It is impossible to build such a large antenna. Instead, we use the concept of using a high-frequency peak to transmit a signal and as a result, we use a 1000 kHz carrier wave to control the signal. The length of the horns can now be;

Rope Length = 3 ∗ 10⁸/1000 ∗ 10³ = 300m

This antenna length can be easily constructed and this example clearly shows us how the process of voice rotation enables communication systems.

1. Wireless communication

By using voice fluctuations to transmit signals from space to longer distances, we have eliminated the need for cables in communication systems. The evolutionary approach has helped people make the most of wireless devices in their lives. Phones no longer needed to be attached to a wall. All the benefits of voice flexibility have increased our standard of living in a tangible way.

2. Interference from other signals

This is a point from the active side of things. Suppose you transfer a baseband signal, as it does to the recipient, say, your friend's phone. Like you, there will be thousands of people in the city using cell phones. There is no way to separate such signals, and they will distract each other, leading to a lot of noise in the system and the worst discharge. By using a high-frequency carrier wave and assigning a frequency band to each message, there is no mixing of signals and the available signals are completely perfect.

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Demodulation Strategies

Some Demodulation Strategies are given below:

Diode Recorder separator

Now let's look at how a wave made of amplitude is detected and released from the body. We need an input signal diode that only allows half a wave. A capacitor is used to remove unwanted radio waves from the original form.

Product Detector

The reduction of the amplitude can be achieved by obtaining signals that include a mixer product detector and a local beat frequency oscillator or carrier injection oscillator. The local oscillator cannot synchronize with the incoming network company and must be in basic form.

Synchronous Converter

This method of obtaining synchronization makes it easy to operate efficiently. This proves to be more useful than other types of AM fluctuations.

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