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What is AM Modulation (Amplitude Modulation)? – Need of Modulation

Detailed Explanation of  AM Modulation (Amplitude Modulation), its working principle, and basic Need of Modulation.

Communication is a process of conveying information at a distance. If the distance is involved is beyond direct communication, electronic communication comes into the picture. One of the principal techniques used in an electronic communication is the modulation.

Modulation Definition:


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Modulation is the process of having the information signal to be transmitted alters a higher-frequency signal for the purpose of transmitting the information somewhere at a higher distance.

In electronic communication we usually study three types of modulation techniques:

  • AM Modulation (Amplitude Modulation)
  • FM Modulation (Frequency Modulation)
  • PM Modulation (Phase Modulation)

The oldest and simplest method is AM Modulation Also known as Amplitude Modulation. And in this article, we will learn about Amplitude Modulation Step by Step. 

What is AM?

AM Modulation (Amplitude Modulation) is the technique in which the Amplitude of Carrier wave varies with the variation in the frequency and amplitude of Information Signal.

Few points to Remember:

  • A carrier wave is High-Frequency, Sinusoidal Signal which has a greater frequency compared to the Information Signal.
  • An Information signal may be audio, video signal which is sinusoidal in nature and it is also referred to as Baseband signal or Modulating Signal.

The concept of AM Modulation (Amplitude Modulation):

In order to transfer information signal at the higher distance, we use Modulation technique and one of the best modulation technique is AM Modulation (Amplitude Modulation) Technique. “In AM Modulation, the carrier wave amplitude changes in accordance with the amplitude and frequency variations of the information signal”.

Give figure below shows the information signal modulating a high-frequency carrier wave. In the modulation process, the carrier’s frequency remains constant only its amplitude varies with the variation of the information signal.

An increase in the amplitude of information signal can cause the increase in the carrier amplitude. Both positive and negative peaks of carrier wave vary with the variation of amplitude of information signal. An imaginary line connecting the positive peaks and negative peaks of the carrier waveform gives the exact shape of the information signal. This imaginary line on the carrier waveform is known as the envelope.

caption id=”attachment_1443″ align=”aligncenter” width=”602″]Amplitude Modulation AM modulation (Amplitude Modulation)[/caption]

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This envelope contains the real information of information signal as it has the exact shape as an information signal. And in order to maintain the real information in the envelope.

The amplitude of the modulating signal should be less than the amplitude of the carrier. When the amplitude of the modulating signal is greater than the amplitude of the carrier, distortion will occur, causing incorrect information to be transmitted.

υm < υc

  • Here Vm is modulating Signal voltage also known as Information Signal voltage:
  • Vc is Carrier voltage.

υm= Vmsin(2πfmt)

  • where υm is the instantaneous value of information sine signal
  • Vm = peak amplitude of information sine signal
  • fm = frequency of modulating sine signal

υc= Vc sin(2πfct)

  • where υc is the instantaneous value of carrier sine signal
  • Vc = peak amplitude of carrier sine signal
  • fc = frequency of carrier sine signal

Using this value of carrier wave voltage and information wave voltage we can calculate the overall modulated wave.


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An envelope is consisting of the information signal in his top and bottom, in order to find out the envelope voltage either for the top or the bottom we can use the equation.

υ1= Vc+ υm= Vc+Vm(sin2πfmt)

Thus, we can write the instantaneous value of the complete modulated wave υ2 by substituting υ1 for the peak value of carrier voltage Vc as follows:

υ2=υ1(sin2πfct)

Now substituting the previously derived expression for v1 and expanding, we get the following:

υ2=(Vc +Vm(sin2πfmt))*sin(2πfct)

= Vc (sin2πfct)+ (Vmsin2πfmt)*(sin 2πfct)

where υ2 is the instantaneous value of the AM wave, Vcsin2πfct is the carrier waveform, and (Vm (sin2πfmt))(sin 2πfct) is the carrier waveform multiplied by the information signal waveform.

It is the second part of the expression that is characteristic of AM Modulation.

A circuit must be able to produce a mathematical multiplication of the carrier and modulating signals in order for AM to occur. The AM wave is the product of the carrier and modulating signals.

AM Modulator

AM Modulator

The circuit used for producing AM is called a modulator. Amplitude modulators perform the product of the carrier and modulating signals.

Generation of an AM wave can be accomplished simply by using a nonlinear device (e.g., diode) in a square-law modulator.

Need for modulation:


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Modulation is needed in a communication system to achieve the following basic needs

  • Multiplexing (Process of transmitting two or more signals simultaneously over a channel)
  • Reduction of antennas Size. (We will cover this in our upcoming articles)
  • Narrow banding (Using modulation technique the bandwidth is reduced we can transmit our information with the less wasting of bandwidth).

Advantages of AM Modulation (Amplitude modulation):-


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  • Generation and detection of AM signals are very easy
  • It is very cheap to build, due to this reason it is most commonly used in AM radio broadcasting.

Disadvantages of AM Modulation (Amplitude modulation):-

  • Amplitude modulation is wasteful of power: The upper and lower sidebands of an envelope are same hence they utilize the amount of power in the Amplitude Modulation.
  • Amplitude modulation is wasteful of bandwidth: The upper and lower sidebands of an AM wave are identical hence they have the same information. This means for the transmission of information only one sideband is necessary. In light of this observation, amplitude modulation is wasteful of channel bandwidth as it requires a transmission bandwidth equal to twice the message bandwidth.

In order to overcome these two limitations of AM Modulation (Amplitude Modulation), we make some sort of modifications in AM Modulation.

These modifications in AM Modulation are known as:

  • Double Side Band Suppressed Carrier (DSB-SC):
  • Single Side Band Suppressed Carrier (SSB-SC):
  • Single Side Band (SSB)
  • Vestigial Sideband (VSB)


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All of these Amplitude Modulation techniques are covered, Click here

Application of AM Modulation (Amplitude modulation):-

  • AM Radio Broadcasting

Also, Read our Article:

  1. Introduction to Electronic Communication.
  2. Types of Electronic Communication (Simplex, Duplex, and Half Duplex).
  3. Practical Applications of Simplex and Duplex Communication.
  4. Modulation Index, | Depth of Modulation | Percentage Modulation
  5. What is Sideband? Single Sideband Modulation, DSB-SC, and Vestigial Sideband
  6. Difference Between TDM and FDM
  7. Greek Alphabet Letters and Symbol

If you like our article on Modulation Definition- What is AM Modulation (Amplitude Modulation)? – The need of Modulation then do not forget to rate our article, and also do not forget to comment below on this article. Thanks for your visit keep connected for the great information.

Introduction to Electronic Communication

In this article we will cover Introduction to Electronic Communication, We will also cover basic terminologies of Electronic communication and we will try to make it useful for you.

Introduction to Electronic Communication

Communication means exchanging information from one place to another, it is what Human beings do to convey their emotions, their thoughts, ideas and feelings to one another. Communication is happening from the beginning of humankind.

Most Humans communicated through the spoken words or with their gestures and postures (Nonverbal communication). Later written communication was developed.

Humans wrote letters to one another and eventually invented newspapers and books. Although the bulk of huge of information is still oral, a huge volume of information is exchanged by means of the written word.

Human communication has faced two barriers in all time; language barrier and distance barrier.

  • When humans of different tribes, races, and nation come together, they often find that they do not speak the same language. This language barrier continues today. But it can be overcome as humans are learning new languages day by day.
  • Communication at long distances is also another big barrier, most communication, in the beginning, it was limited to face-to-face conversation. However, for long-distance communication humans uses signals with drums, horns or smoke signals.


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Other early forms of long-distance communication were lighting a signal fire, waving a flag (semaphores), but despite all these attempts of long-distance communication, transmission distance was limited.

If the signal could be launched from a hill, mountain or high towers, the distance of several miles could usually be achieved only.

Human communication took a huge turn in the late 19th century when electricity was discovered and its many applications were explored. The telegraph was invented and the telephone and the radio were discovered.

It was the time when an exchange of information took a great leap forward.

Important Milestone in History of Communication are Given Below:


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An Electronic Communication, such as Telephone, Radio, and Television, have increased our ability to share and convey information of long-distance. Today they are the major part of our lives.

Despite these basic types of long-distance communication platforms, now we have internet, we write E-mails to communication, we have social media platforms like Google, Facebook, and Yahoo. These all types of communication platforms have not replaced the old telephone, radio or television but they have simply added a new way for people to interact with one another.

It is hard to imagine what our lives would be like without the knowledge and information that arrive from around the world by electronic communication.

Ours is an information society, and a key part of it is communication. Without electronic communications, we could not access the available information in a timely way.

The so-called information superhighway of the future is an electronic communication technology.

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The Elements of an Electronic Communication System:


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All electronic communication system has three basic elements, Transmitter, Medium or channel and a Receiver.

In real Human or Source generate a signal, that contains the information and that signal is sent to the transmitter which transmits the information over a communication channel. And then the message is picked by the receiver and receiver gives that information to the desired destination say human.

In this process. A noise is always added to the information through the communication channel. A noise may be due to environmental effects, temperature, or not proper working of an instrument.

block diagram of electronic communication systems

Transmitter:

The transmitter is the collection of electronic components or a circuit. Which is designed to convey the information into a suitable electrical form for communicating with the channel.
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It may be a simple microphone as most radio uses.

Communication Channel:

The communication channel is the medium by which the information is sent from one place to another.

As a voice signal uses air medium for face-to-face communication. As that an electronic communication uses an electronic medium for sending information from one place to another.

For an Electronic communication, a medium may be the simple pair of wires which transmit the information signal which is taken form microphone.

On the other hand, a medium may be a wireless or Radio, Radio makes use of electromagnetic spectrum where signals are communicated from one point to another.

Receiver:

The receiver is also another electronic circuit, which accepts the transmitted information from the channel and converts it back into a human understandable form.

A receiver may be the Speaker or complex electronic receiver.

Noise:

A Noise is random, undesirable electrical energy that enters the communication system through the communication channel and interface with transmitted Information Signal and attenuates the information signal.


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Noise may be generated by the thermal radiation of electronic components, improper environmental conditions can also cause the noise signal. Although such noise signals are the very low-level signal. But they produce more serious problems in electronic communication.

For the most part it cannot be completely eliminated, however, it can be reduced on some level.

Source of information: Communication Electronics (Principal and Applications) by… Louis Frenzel
Also Read:
  1. Types of Electronic Communication (Simplex, Duplex and Half Duplex)
  2. Practical Applications of Simplex and Duplex Communication
  3. What is AM Modulation? – Need of Modulation
  4. Modulation Index, | Depth of Modulation | Percentage Modulation
  5. What is Sideband? Single Sideband Modulation, DSB-SC, and Vestigial Sideband
  6. Difference Between TDM and FDM
  7. Greek Alphabet Letters and Symbol

This is all about Introduction to Electronic Communication If you liked our post give a share and appreciate the efforts be commenting down below. Stay connected for better information.

Differece between TDM and FDM

Difference Between TDM and FDM

In this article, we will learn what are the difference between TDM and FDM. We will start with the basics and we will see each of the differences between them.

Difference between TDM and FDM

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In telecommunication, Multiplexing is the process of sending two or more individual signals over a single communication channel this is usually achieved by an electronic circuit known as a multiplexer. In telecommunication, the two most common type of multiplexing techniques are TDM and FDM. Both have their own advantages and uses, in this article, we will cover all Differences between TDM and FDM. 

The common difference between TDM and FDM is that TDM share the timescale for the different signals; Whereas FDM shares the frequency scale for the different signals.

Difference Between TDM and FDM (With Comparison Chart)

PARAMETERTDMFDM
Definition TDM is the transmission technique in which different signal are transmitted over a common channel and each signal occupies entire range of bandwidth in the time domain.FDM is the transmission technique in which different signal are transmitted over a common channel and each signal occupies different slot within that bandwidth of the frequency domain.
Stands ForTDM means Time-Division MultiplexingFDM means Frequency-Division Multiplexing
Useful forTDM can be used for both Analog and Digital signals.FDM can be used for Analog signals only.
SynchronizationTDM requires Synchronization.FDM does not requires Synchronization.
CircuitTDM circuitry is very simple to built.FDM circuitry is very complex.
Cross TalkTDM is not sensitive for Cross Talk (Noise Immunity)FDM suffers from the cross talk immunity due to Bandpass Filter.
RequirementTDM requires sync pulse for its operation.FDM requires Guard bands for its operation.
EffiecientTDM is more efficient and is widely used technique in multiplexing.FDM is less efficient compared to TDM.
ApplicationsTDM is used in Pulse code modulation.FDM is used in TV and RADIO broadcasting.

What is TDM:

Time-division multiplexing (TDM) is a method of transmitting and receiving multiple signals over a single channel; each signal occupies entire bandwidth of the channel. However, each signal is transmitted for a short period of time or in other words, each signal is allowed to use a channel for a fixed time.

One of the major difference is that TDM can be used for both digital and analog signals.


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Figure down below shows the concept of Time-Division Multiplexing:

TDM (Time-division Multiplexing)

What Is FDM:


Frequency-division multiplexing (FDM) is a method of transmitting and receiving multiple signals over a single channel, each signal being allocated a portion of the spectrum within that bandwidth. FDM can be used for analog signals only. FDM technique is the most widely used technique in multiplexing.

The most common example of FDM is TV and RADIO broadcasting, in which a number of RADIO signals at different frequencies are passed through the air at the same time.

Another good example is cable TV, in cable Television, different television channels are carried at the same time on a single cable.

Figure down below shows the concept of Frequency-Division Multiplexing:

Differece between TDM and FDM

  Read More: What is the Duty Cycle?

Key Differences between FDM and TDM


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  1. FDM divides the channel bandwidth into smaller frequency ranges so each user can transmit data simultaneously through a common channel, while TDM allocate a fixed time for each user for the transmission of data over a common channel.
  2. FDM uses Analog transmission system
  3. TDM uses both analog and digital transmission system.
  4. In FDM Synchronization is not required between Signals and multiplexer Circuit.
  5. In TDM synchronization is required between signals.
  6. FDM provides less flexibility compared to TDM.
  7. FDM circuitry is more complex than TDM circuitry.
  8. TDM is employed in Pulse-Code-Modulation transmission.
  9. FDM is employed in Telemetry systems, RADIO and TV broadcasting.
  10. FDM suffers more Cross talk issue compared to TDM.

Read More: Download any E-Book for Free from Z-Library

Conclusion:
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Both FDM And TDM are the techniques of multiplexing, the only difference between TDM and FDM is that in FDM, individual signals for transmission are given a different frequency within a common bandwidth. In TDM, the multiple signals are transmitted in different time slots on a single channel.

Also FDM is used for analog transmission of signals for example transmission of Audio signal at RADIO is achieve by FDM. Whereas TDM can be used for both analog and digital signals in computer-based communications TDM is widely used, However in terms of their efficiency TDM has much greater efficiency than FDM.

Source of images: Multiplexing and spreading

  1. Introduction to Electronic Communication
  2. Types of Electronic Communication (Simplex, Duplex and Half Duplex)
  3. What is AM Modulation? – Need of Modulation
  4. Modulation Index, | Depth of Modulation | Percentage Modulation
  5. What is Sideband? Single Sideband Modulation, DSB-SC, and Vestigial Sideband
  6. Greek Alphabet Letters and Symbol

What is Sideband? Single Sideband Modulation, DSB-SC, and Vestigial Sideband

Detailed Explanation of different types of Sidebands, Including Single Sideband Suppressed carrier, Dual-Sideband Suppressed Carrier, and Vestigial Sideband.

What is Sideband in AM Modulation:


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Whenever a carrier signal is modulated by the information signal, new signals at different frequencies are generated as the part of AM modulation. These new frequencies are called Sidebands or Side frequencies. These new frequencies can be seen in the frequency spectrum as shown in the figure below. The Signal component above the carrier frequency is known as Upper Sideband and the signal below the carrier frequency is known as Lower Sideband.

The upper sideband f(USB) and lower sideband f(LSB) are calculated as:

fUSB = fc +fm    and    fLSB = fc – fm

Where:

  • fc is the carrier frequency
  • fm is the modulating frequency
Sidebands in AM Modulation

Sidebands in AM Modulation

For example, if 800 kHz carrier is amplitude modulated by a 2 kHz audio signal, there will be components at 799 kHz and 801 kHz as well as 800 kHz in the generated AM Modulation frequency spectrum.

The existence of sidebands can be proved mathematically:

Using the equation for an AM signal described previously:

υAM =Vc sin 2πfct + (Vm sin 2πfmt) (sin 2πfct)

Now applying trigonometric Identity of a product of two sine waves are:

trigonometric produce of sine wave

And substituting this identity into the expression of AM modulation equation we get:

Amplitude Modulation Equation

Amplitude Modulation Equation with sidebands

Here you can see the first term is the carrier, the second term is, contains the different of lower sideband and the third term contains the upper sideband.

Now it is obvious that during AM Modulation process sidebands are generated.

Single Sideband Modulation:

In AM Modulation (Amplitude Modulation) process two third of the power is consumed by the carrier wave, which itself does not convey any information. The real information is contained within the sidebands. In order to make AM modulation efficient, we can suppress the carrier and eliminate one sideband because each sideband contains the same information the best trick will be eliminating one of the sidebands. This is known as Single Sideband Modulation.
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Single Sideband Modulation

Single Sideband Modulation

Signal Sideband or (SSB) is the form of Modulation which has lots of benefits in Electronic Communication and Radio transmission.

Read More: Download any E-Book for Free from Z-Library

Two Achieve Single Sideband Modulation we have to first understand:

  • Dual-Sideband Suppressed Carrier (DSSC or DSB):
  • Single-Sideband Suppressed Carrier (SSB):  

Dual-Sideband Suppressed Carrier (DSSC or DSB)


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In Dual-Sideband Suppressed carrier we suppress carrier wave, The benefit, of course, is that no power is wasted on the carrier. In simple words, Dual-Sideband Suppressed carrier is the special case of AM modulation with no carrier. A frequency-domain display of a DSB signal is shown below. Note that the spectrum occupied by AM Modulation and DSB Signal is same.

Dual-Sideband Suppressed Carrier

Dual-Sideband Suppressed Carrier

Double-sideband suppressed carrier signals are generated by a circuit called a balanced modulator. The purpose of balance modulator to produce fUPS and fLPS and suppress carrier. The elimination of carrier wave does not make DSB to be used widely because it saves one-third power but the regeneration of information signal is not easy in DSB modulation.

Here in Time domain, you can see that by eliminating carrier wave the modulated signal undergoes a phase reversal whenever the message signal m(t) crosses zero. The envelope of a Dual-Sideband Suppressed Carrier modulated signal is different from the information signal.

DSB-SC Time Domain

The transmission bandwidth required by Dual-Sideband Suppressed Carrier modulation is the same as that for amplitude modulation which is twice the bandwidth of the information.

Single-Sideband Suppressed Carrier (SSB):

In DSB-SC there were no carrier but only two sidebands, and in Single- Sideband Suppressed Carrier there is suppressed carrier and one sideband elimination. Making it more useful in Electronic Communication and RADIO transmission.

Single Sideband Modulation

Single Sideband Modulation

Few advantages of SSB Modulation are:
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  1. The primary benefit of an SSB signal is that the spectrum space it occupies is only one-half that of AM and DSB signals. This allows more signals to be transmitted in the same frequency range.
  1. The power which was being utilized in a carrier and one sideband is reduced hence the more power will be consumed by only one sideband and the greater distance can be achieved by SSB Modulation.
  2. Because SSB signals occupy a less bandwidth, the amount of noise in the information signal is also reduced.

Disadvantages of DSB-SC and SSB-SC
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The main disadvantage of Dual-Sideband Suppressed carrier and Single-Sideband Suppressed Carrier signals is that they are harder to recover or demodulate at the receiver end. Because demodulation depends on the carrier being present. If the carrier is not present at the receiver end then it must be regenerated at the receiver and reinserted into the signal, in order to achieve faithful recovery of the information signal. The reinserted carrier must be in same phase and frequency as the original carrier had.

This is the very difficult requirement in DSB and SSB Modulation in order to make a proper modulation we use vestigial side modulation.

VSB (Vestigial) Modulation:

A vestigial-sideband system is a combination of DSB and SSB It has the advantages of DSB and SSB but avoids their disadvantages. The Idea is to transmit one of the sidebands similar to SSB but also transmit a vestige (small trace) of the other sideband. So, VSB has a larger bandwidth compared to the SSB but smaller than DSB-FC

Vestigial Sideband

Vestigial Sideband

Why Use VSB?
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  • In DSB, we wasted power and bandwidth but the receiver was simple
  • In SSB, we saved power and bandwidth but the receiver was complex, Complex means more expensive
  • In VSB, we can reduce the complexity and save bandwidth to an extent

To generate a VSB modulated wave, we pass a Dual-Sideband Suppressed Carrier modulated wave through a sideband shaping filter as shown in Fig.

Vestigial Sideband Modulator

Vestigial sideband modulation has the advantage of having bandwidth almost as efficiently as single sideband modulation while retaining the low-frequency characteristics of double sideband modulation. The VSB modulation has become very helpful for analog transmission of television and RADIO signals.

Summary of All three types of Modulation Techniques:

Types of AM Modulation

Also Read:
  1. Introduction to Electronic Communication
  2. Types of Electronic Communication (Simplex, Duplex and Half Duplex)
  3. What is AM Modulation? – Need of Modulation
  4. Modulation Index, | Depth of Modulation | Percentage Modulation
  5. Difference Between TDM and FDM
  6. Greek Alphabet Letters and Symbol

Modulation Index, | Depth of Modulation | and Percentage Modulation

It is one of the important factors in AM Modulation (Amplitude Modulation) if the Modulation index is applied less than the overdamping will occur or in simple words, the envelope will be overdamped and the Information signal will not be same at the receiver side. The same case is true when the Modulation index is made greater than the normal limit.


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In order to make AM Modulation perfect, we need to study Modulation Index which is also known Modulation Depth.

In this article, we will learn about Depth of Modulation or Modulation Index Step by step. We will also cover Percentage Modulation in this article.

What is Modulation Index?

For AM Modulation (Amplitude Modulation): “Modulation Index is defined as the relationship between the amplitude of the Information signal and the amplitude of the carrier signal“.

Modulation Index is the ratio.

m=Vm/Vc

Where:

  • Vm is the amplitude voltage of modulating (Information) signal.
  • Vc is the amplitude voltage of carrier signal.

Multiplying the ratio of modulation index by 100 gives the percentage modulation.

m=Vm/Vc*100

For example, if the carrier voltage is 8 V and the modulating (information) signal voltage is 6.5 V, then the modulation index will be 0.8125. Using the above equation it can be seen that a Modulation Index of 0.90 means that the signal will increase by a factor of 0.90 and also decrease to 0.10 of its original level.

Importance of Modulation Index in AM Modulation:

The modulation index is a ratio and hence the modulation index should be a number between 0 and 1. If the amplitude of the information signal voltage is higher than the carrier voltage, m will be greater than 1, causing distortion in AM wave.

Vm>Vc (Distortion will occur)

If the distortion is great enough, the information signal becomes not usable. Distortion of voice transmissions produces unnatural sounds or noise in the speaker. Distortion of video signals produces an inaccurate picture on a TV screen.

Effect of Modulation Index on AM Modulation:

To understand Modulation Index in the better way let’s have few examples of AM Modulated waveforms with different levels of Modulation Index.

First Case: When m=0

When there is no information signal there is no presence of AM modulation, from given picture you can see there is only carrier signal hence this condition is not useful because it does not provide us any information.

modulation index at m=0

modulation index at m=0

Second Case: When m=0.5

In this case, you can see the modulation index is 0.5, this is a condition in which AM modulation is not desirable because the carrier signal will not fall to zero references hence some amount of information is also lost in this condition. In this condition, carrier voltage is much greater than the information signal voltage. And also this condition is not suitable for AM modulation because we do not get exact information, and in this condition, 50% modulation is achieved.

modulation index at m=0.5

modulation index at m=0.5

Third Case: When m=1

Here you can observe that carrier voltage and information signal voltages are equal hence this condition is achieved. In this condition we get perfect AM modulation, you can see from given figure that the carrier signal falls on zero references and in this condition 100% modulation is achieved.


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modulation index at m=1

modulation index at m=1

Fourth Case: When m>1

This is the worst case when the information signal voltage is much greater than the carrier signal this case happens and in this case greater than 100% modulation is achieved which is not useful because it goes in overmodulation. In this condition we do not get an exact envelope hence we do not get exact information of information signal as shown below.

modulation index at m>1

modulation index at m>1

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Summary of All four Cases of Modulation Index:


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modulation index

Summary of modulation index

AM modulation is widely used in AM broadcasting in order to ensure that the transmission never becomes distorted or overmodulated. They use Automatic circuits called compression circuits, which solve this problem by amplifying the lower-level signals and suppressing or compressing the higher-level signals. These circuit results in higher average power without overmodulation.

Also, read about Communication:

  1. Introduction to Electronic Communication.
  2. Types of Electronic Communication (Simplex, Duplex, and Half Duplex).
  3. Applications of Simplex, and Duplex Communication.
  4. What is the Amplitude Modulation?
  5. What is Electronic? Difference between Electrical and Electronics

Image courtesy to: Learn CBSE Forum

This is all about the modulation depth and percentage modulation, if you like our article do not forget to rate, and also do not forget to comment down below. Thanks for your visit and stay connected with StudentsHeart.com for best and useful information.

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