Modulation

If you have ever listened to the radio on the car, on your home, you must be aware of FM and AM. Moreover, you will also notice that each radio station has a unique address on the FM and AM scale. Such a phenomenon behind radio transmission travelling from your favourite FM station to your audio device is one of the most important uses of modulation. 

From radio stations to various other modes of communication, modulation is significantly important. In this topic, the primary focus will be on what is the need of modulation. 

However, before that, it is vital to understand the fundamentals of modulation. So, check these following concepts which explain the same.

What is the Definition of Modulation?

Modulation can be defined as the process of conversion of data into waves by adding information to a carrier signal. Such a signal can be an electronic or an optic carrier, but most importantly, it should possess a steady waveform.

A signal with a steady waveform indicates that it possesses a constant amplitude and frequency. Moreover, one can add information on such a carrier through modulation by altering its frequency, phase, amplitude, polarization in case of optical signals as well as electronic or even quantum signals such as varying the spin. 

Why Modulation is Necessary for Communication?

The necessity of modulation is mainly visible in the electronic field as it is applied to electromagnetic signals such as radio waves, lasers, electronic chips, etc. for an efficient mode of communication among various devices. 

For example:

In cases where an engineer needs to control the signals sent by the energy generated by a DC motor, he or she can apply modulation to direct current. Here, it will be treated as a degenerate carrier wave which has a constant amplitude and a fixed frequency of 0 Hz.

As per the above example, it is easier to gauge the need of modulation in communication systems. Moreover, one can also turn the modulation ON or OFF, which helps in easier delivery and reception of signals, just like the Morse code theory or direct current loop interface.

Furthermore, in various cases, a modulated signal may turn out to be a ‘no carrier’ which means any response message will indicate that any number of attached devices are no longer connected to the remote network system. Such a phenomenon is known as baseband modulation.

What is Modulation in Communication?

Modulation is an essential process to ease communication between several electromagnetic mediums. Moreover, multiple carriers of data, each having different frequencies can be transmitted over only a single media if an independent signal modulates each carrier.

Additionally, one can also apply modulation to alternating current with a low rated frequency. Usually, alternating current used in our daily lives has a frequency of 50 to 60 Hz. Modulation can be applied to alternating current of such frequencies with the help of powerline networking.

Before we carry on with our discussion on why modulation is required, brush up your memory with the help of this ‘fill in the blanks’ section given below –

Test Your Knowledge

Fill in the blanks with the correct answer from the options given below.

  1. Modulating wave can also be termed as a _________ wave.

  1. comparing 

  2. transmission

  3. measuring

  4. optic


  1.  A Waveform can be referred to as a curve at _______.

  1. all times

  2. a given time

  3. certain time periods

  4. no given time


  1. One of the most important advantages of modulation is that _______.

  1. signal mixing occurs

  2. signal mixing does not occur

  3. range of communication decreases

  4. adjustments in bandwidth are disallowed


Types of Modulation

Modulation is of various types based on the alteration of various factors such as frequency, amplitude, etc. on each modulated signal. They are –

  • Amplitude modulation (AM)

  • Frequency modulation (FM)

  • Phase modulation (PM)

  • Pulse code modulation

  • Polarization modulation

  • Quadrature amplitude modulation (QAM)

Each type of modulation has its own sets of advantages and disadvantages. For example, AM is usually used in shortwave, whereas FM is used in longwave radio transmission.

At Vedantu, we hope that this study material on the topic of various needs of modulation will help students to get a better understanding of the subject matter. Download our Vedantu app to access study material and learn more about our online tutoring service!

FAQ (Frequently Asked Questions)

1. Give a Common Example of Modulation?

Ans. Signals sent and received through Wi-Fi are a prime example of modulated signals.

2. Name Three Types of Modulation?

Ans. There are various types of modulation such as amplitude modulation, frequency modulation and phase modulation. 

3. What Kind of Modulation is Associated with ‘no carrier’ Signals?

Ans. A ‘no carrier’ signal implies that there has been an occurrence of baseband modulation.