Difference between Analog Communication and Digital Communication



In electrical and electronics engineering, the communication is defined as the process of broadcasting, transmitting, storing or viewing the data and information using electronic devices and circuits.

Based on the nature of signals and devices used for processing the information, the electronic communication can be classified into following two types −

  • Analog Communication

  • Digital Communication

In this post, we will take a look at the major differences between analog communication and digital communication by considering various parameters such as basic definition, cost, hardware technology, noise, power requirement, need of modulation, applications, etc. Also, a short description of analog communication and digital communication is added for your reference.

What is Analog Communication?

The type of communication in which the data and information is transferred with the help of analog signals in between transmitter and receiver is called the analog communication. Therefore, the analog communication uses continuous time signals for transmission of information.

The process involved in analog communication is illustrated in Figure-1. Where, the information in the form of analog signal is input to a transducer, which supplies it to the modulator. The modulator broadcast the modulated information on a communication channel. At receiver end, a demodulator circuit is employed for extracting the information from the modulated signal to produce the output message.

What is Digital Communication?

The communication in which the information is transferred by using digital signals in between transmitter and receiver is known as digital communication.

Hence, in case of digital communication, discrete time signals are used for carrying the information from one point to another. The block diagram shown in Figure-2 illustrates the digital communication system.

Here, the information is first encoded in digital signals (binary form) and modulated. The modulator then broadcast the information in digital form (in the form of data packets) on the communication channel. On the receiver end, the demodulator recovers the information and supplies it to the decoder, so that output message can be obtained.

Difference between Analog Communication and Digital Communication

The following table highlights the fundamental differences between analog communication and digital communication −

Basis of Difference
Analog Communication
Digital Communication
Definition
The method of information transmission between transmitter and receiver in which analog signals are used for conveying the information is known as analog communication.The communication in which digital signals are used for transferring information between transmitter and receiver is known as digital communication
Type of signals used
Analog communication uses continuous time signals.Digital communication uses discrete time signals.
Major components
The main components used for analog communication are: transmitter, transducers, modulator, channel, demodulator and receiver.The components of digital communication are: transmitter, encoder, modulator, channel, demodulator, decoder and receiver.
Signal representation
In analog communication, the sinusoidal waveforms represent the signals used for transferring information.In digital communication, the signals used for information transmission are represented by square waveforms.
Bandwidth
Analog communication needs low bandwidth.High bandwidth is required in digital communication.
Noise
Analog communication is less immune to noise.The immunity to noise of digital communication is good.
Separation of noise
In analog communication, it is not possible to separate the noise signal from message signal.In digital communication, the noise can be easily separated from the message signal.
Error
The probability of error in analog communication is high.Digital communication has less probability of errors.
Hardware design
Analog communication involves complicated and less flexible hardware design.The hardware design of digital communication is simple and more flexible than analog communication.
Modulation techniques
The modulation techniques used in analog communication are: ‘pulse amplitude modulation (PAM)’, ‘pulse width modulation (PWM)’, ‘pulse position modulation (PPM)’.The modulation techniques used in digital communication are − ‘amplitude shift keying (ASK)’, ‘frequency shift keying (FSK)’, ‘phase shift keying (PSK)’.
Multiplexing technique
Analog communication uses frequency division multiplexing (FDM).Digital communication uses time division multiplexing (TDM).
Power consumption
Analog communication involves high power consumption.Digital communication consumes less power.
Security
Analog communication is comparatively less secured.Digital communication is highly secured.
Synchronization
In case analog communication, synchronization of difference components is hard.The synchronization is easier in case of digital communication.
Accuracy
Analog communication is less accurate.The accuracy of digital communication is high.
Number of broadcasting channels
In analog communication, there is a limited number of communication channels that can be broadcasted simultaneously.In digital communication, a large number of communication channels can be broadcasted simultaneously.
Portability of components used
The components used for analog communication are heavy, hence are less portable.Digital communication involves compact components, hence their portability is high.
Cost
Analog communication involves less cost for information transmission.The cost of digital communication is comparatively high.

Conclusion

Due to many technical and economic advantages, digital communication has now become the preferred mode of data transmission over analog communication.


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