Difference Between Analog and Digital Modulation (With Table)

We need modulation to transfer signals from one medium to another medium. These mediums can be either a physical medium or through any other medium. The two most modulations that are in existence and are used by people are analog modulation, and the other one is digital modulation. This digital modulation is preferred by many people because of its security and fast features. 

Analog vs Digital Modulation

The difference between Analog and Digital Modulation is that analog modulation is a continuous signal which means the signal can be changed over some time. On the other hand, digital modulation is a discrete signal which means it will carry only binary information. The wave that is used in analog modulation is the sine wave. But the wave used in digital modulation is a square wave. 

Analog modulation will determine the wave in continuous modulation where the time differing in the variable will be mentioned. It also helps in transmitting low-frequency signals. Also, it supports audio signals that have high-frequency carrier signals. It has three different types, each one having its unique properties. If the values lie between the specified range, then they are considered to be valid. 

Digital modulation will provide high security, and the information can be passed very quickly in this method. They have a good capacity to transfer large amounts of data through analog media, and this main reason makes it to be in more demand. Depending on the type of combinations that we are going to use for our work, we can choose the type of modulation from the three modulations that are provided.

Comparison Table Between Analog and Digital Modulation

Parameters of ComparisonAnalog ModulationDigital Modulation
Value RangeIt can represent any value that is between the specified rangeIt will represent only a set of values within the specified range
Signal separationIt is difficult to separate themIt can be easily separated
WaveSine WaveSquare wave
DefinitionIt is a continuous signal that can be changed over some timeIt is a discrete signal carrying the information in binary form
TriggeringSingle-stage triggeringSequential triggering

What is Analog Modulation?

It is the process by which the signals will be transferred in analog baseband. There are three types of analog modulation, and they can be differentiated based on carrier signal property. The best example of analog modulation is amplitude modulation in this modulation. The carrier wave amplitude will be varied with the modulation signal. 

The next best example is frequency modulation. In this modulation, the carrier wave frequency will be varied by the modulation signal. When we have a bandpass channel, then this kind of frequency is very important. These frequencies will be transmitted through a bandpass filter which will allow only specific signals to pass so that unwanted frequencies can be avoided. This type of modulation can be seen in FM Radio, short wave broadcasting, and AM. 

Sometimes we can convert analog modulation to digital modulation as well. For that, we need to follow some simple steps. First, we have to take the sample of the signal and, once it gets qualified so that we can determine the resolution of the signal. Then we have to set binary values for that so that when we send it to the system so that it can read the digital signal. When we do this, we have to keep two important aspects in our minds. One is the sampling rate, and the other is resolution. 

What is Digital Modulation?

It is the process by which the digital information will be encoded to the frequency of the transmitted signal. In this process, the encoding process will affect the bandwidth of the signal that is transmitted. It uses techniques that can be either linear or non-linear. There are three types of digital modulation available. In this modulation, the digital signals will be transmitted through the analog signal with a higher frequency.

This modulation will enable us to transmit signals that are generated in a digital circuit through a physical medium. The reason why they use this is that they can handle signals with higher security, and nothing will get damaged in this process. This kind of security is not expected in other modulations. And also, the digital systems that are used here are widely available in the world. 

The advantage of using digital modulation is you can operate it with a much lower noise ratio. Here the output level will not be dependent on the optical level. Also, you won’t be able to find any degradation in the system. In this modulation, you will be able to get more specific information about the data, and the access will be faster as well. Therefore, it is in very huge demand because of the qualities that are mentioned above.  

Main Differences Between Analog and Digital Modulation

  1. In analog modulation, it can have value any value between the specified range. On the other hand, digital modulation can have only a set of values in the specified range.
  2. The signal separation is very difficult in analog modulation. On the other hand, signal separation is very easier in digital modulation.
  3. Analog modulation uses sine waves. On the other hand, digital modulation uses square waves.
  4. Analog modulation is a continuous signal that can be changed over a period of time. On the other hand, digital modulation is a discrete signal that will carry binary information.
  5. Analog modulation uses single-stage triggering. On the other hand, digital modulation uses sequential triggering. 

Conclusion

Both these modulations are used for passing signals. Based on the type of user requirement, we can determine which modulation can be used. Among these, digital modulation is very widely used. Because of the high-security features and fast modulation techniques, digital modulation is preferred by many people.

To know more about these modules in-depth, then we should have taken physics as our major subject in higher studies. So that we will be able to do more research on that topic. Once we get a hold of it, we can do some specific research, and it will help us to explore more on this topic. Remember that we have to meet the requirements of our work to determine the modulation. 

References

  1. http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.636.1429&rep=rep1&type=pdf
  2. https://www.sciencedirect.com/science/article/pii/0165168495000992
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