Digital Communication

Digital Communication involves the physical transfer of data and information through a suitable communication channel. This exchange of information in the form of discrete messages can take place Point to Point or Point to Multipoint. Conventionally analog signals have been used to establish a connection and start communication over large distances but this made the signals suffer many losses such as distortion, interference, and even security breaches. These problems were overcome by the usage of digital signals over analog ones. Analog signals are digitized using different techniques. Communication using these digital signals makes it more accurate and less vulnerable to losses or breaches.

Basic Components of Digital Communication

Digital Communication has the following basic components:

• Source: Any point of data origin that can offer a piece of information that may be analog or digital can consider a source.

• Input Transducer: The transducer at the input end performs the task of converting a physical input from point of source into an electrical signal. It is also equipped with an analog to a digital converter where the analog signal needs to be digitized for further transfer or exchange. This digital signal is nothing but a sequence of binary numbers, i.e. 0s and 1s.

• Source Encoder: At the source encoder, the compression of the digitized signal data is done to minimize the number of bits while maintaining the correctness of the data. For the compression removal of redundancy is an important step. In this way, the effective utilization of the bandwidth is ensured.

• Channel Encoder: The compressed data from the source code is encoded for error correction using a channel encoder. To prevent the alteration of the data signal during transmission because of noise in the channel, the channel encoder adds a few redundant bits to the data being transmitted called the error-correcting bits.

• Digital Modulator: The transmitting channel modulates the signal to be transmitted and also the signal can be converted from digital format to analog hence making it ready to travel along with the medium.

• Channel: Channel is a transmission medium through which the signal transmission takes place.

• Digital Demodulator: On the receiver side, the received signal is demodulated and also conversion from analog to digital takes place using a digital demodulator. Signal reconstruction takes place here.

• Channel Decoder: Error corrections are done using redundancy bits after sequence detection by the channel decoder.

• Source Decoder: By using sampling and quantization the final signal is again converted into digital format.

• Output Transducer: Here the output signal is converted from the electrical form to the physical form.

• Output Signal: Signal that is produced after the complete process as the output is the output signal.

The terms Data Communication and Digital Communication share a common word, i.e. Communication between them. Communication that natively means to share something; makes these terms look similar, but they are quite different from each other. While one term relates more to what is being communicated other is closer to what is the type and process of sharing involved during communication. Let us explore more into it now.

Data communication is a broader term that encompasses the transfer of any type of data between two points, while digital communication specifically refers to the transfer of digital signals over a communication channel. While the two terms are related, it is important to distinguish between them based on the specific context in which they are used.