+
JEE Exam » JEE Study Material » Physics » Basic Elements of Communication Systems (Block Diagrams)

Basic Elements of Communication Systems (Block Diagrams)

Communication is the act of transmission of information. Every living creature within the world experiences the necessity to impart or receive information virtually unceasingly with alternatives in the close world. For communication to be successful, the sender and receiver must perceive a standard language. Man has perpetually created endeavours to enhance communication with other human beings. Languages and ways utilised in communication have been unbroken, evolving from prehistoric to fashionable times to fulfil the growing demands of speed and quality of information.

There are three critical components to every communication system: the transmitter, the channel, and the receiver.

Basic components of communication system

The information can be sent over a communication system from either a person or a machine. A transmitter is positioned at one location, and a receiver is located at another location, with the channel serving as a medium between the two locations. It is the message signal that originates from the source, and it is this signal used to feed into the transmitter.

The signals that are conveyed are referred to as transmitted signals. Transducers transform nonelectrical signals into electrical signals when the message signal from the source of information is nonelectrical.

The physical media that links the transmitter and receiver (whether wired or wireless) is the channel. It is possible that the broadcast signal may be warped due to its imperfection and that some noise will be added to the transmitted signal as it propagates.

An in-depth examination of the components of the communication system, Information is the concept or message being given. It is also known as knowledge. The message may consist of a single message or a series of messages. The message might take the form of a symbol, a code, a sequence of words, or any other predetermined unit.

A Bandwidth, Information, Signal, Transducer, Amplifier,  Modulation and Modulator are all transmitter components in radio transmission. Transducers are also known as transmitters.

Bandwidth

The bandwidth is the difference between the higher and lower frequencies in a continuous range of frequencies. It is usually expressed as a frequency in hertz (Hz).

Information

A piece of information is an idea or message that is being transmitted. If there are many communications, they are referred to as a chain of messages. The message can take the form of a symbol, a code, a set of words, or any other predetermined unit of information or communication.

Signal

In other words, it is Information turned into an electrical form that can be sent. Analog and digital signals are also possible. When it comes to analogue signals, fluctuations in voltage or current happen continuously. They are simply functions of time that have only one value. Amon Analogue Of signals, the sine wave is the most basic. Ethnologue signals can be understood entirely in their sine wave components, which are the building blocks of all analogue signal types. Television transmissions analogue of, including both the sound and image signals. It is only possible to take discrete stepwise values with digital signals. Using only two signal levels, the binary system, widely used in digital electronics, may be described as follows: An ‘O’ indicates a low level of voltage or current, whereas a ‘1’ indicates a high level.

Transducer

It is a device that transforms one type of energy into a different kind of energy by using heat. When it comes to electrical transducers, they may be described as devices that transform some physical variable (such as pressure or displacement) into equivalent changes in an electrical signal at their output. Microphones, tape heads, photocells, LEDs, and so on are examples of electronic components.

Amplifier

An amplifier is an electrical circuit or device that boosts the amplitude or the intensity of a conveyed signal. When the signal intensity falls below the desired level, amplification can be performed anywhere along the path between the transmitter and the receiver. A direct current power source will power the amplification.

Modulation

A low-frequency message/information transmission cannot be transferred across long distances because of the nature of the original signal. Because of this, during transmission, the information contained in the low-frequency message signal is overlaid on a high-frequency wave that serves as a carrier of the data. Modulation, a term that refers to this procedure AM, FM, and PM, are the abbreviations for several forms of modulation.

Modulator

For reasons of frequency and amplitude, the original message signal cannot be sent over a long distance and must be overlaid with a wave of high frequency and amplitude known as the carrier wave instead. Modulation is the term used to describe the phenomena of a message signal superimposed over a carrier wave. And the resulting wave is a modulated wave intended to be communicated to the recipient.

Note:

  • A transducer is an electronic device that transforms sound waves into electric signals.
  • An audio modulator is a device that combines an electric audio signal and a high-frequency radio wave.
  • The modulated signal is amplified by the amplifier, which increases its power.
  • With the help of an antenna, the signal is broadcast into the surrounding space.
  • An in-depth examination of the components of the communication system

It is the responsibility of the communication channel to transport the modulated signal from the transmitter to the receiver. Communication channel definition: The communication channel is sometimes referred to as a transmission link or a medium of transmission.

In radio communications, the phrase “channel” refers to the frequency band that has been assigned to a particular broadcast or service.

Different kinds of communication system

There are different kinds of communication systems based on the type of modulation used:

(i) Amplitude modulation is one kind of modulation (AM)

(ii) Frequency modulation is another kind of modulation (FM)

(iii) Phase modulation is a kind of modulation (PM)

(iv) Pulse amplitude modulation is a kind of modulation (PAM)

Modulation

As digital and analogue signals have a low frequency, they cannot be sent across long distances. These signals need the use of a carrier. Carrier waves or high-frequency signals are the terms used to describe these carriers. Modulation is the placing of a low frequency (LF) signal on top of a high frequency (HF) signal and is defined as follows:

Modulation is required because the sound wave (20 Hz to 20 kHz) cannot be transferred straight from one location to another due to the following reasons:

It is recommended that the transmitting and receiving antennas have a height similar to a quarter of the frequency’s wavelength to provide efficient emission and reception. It is 5000 m for 15 kHz (which is much too huge) and 75 m for 1MHz (also far too large).

When the signal frequency to be sent is less than 15 Hz, the amount of energy emitted by an antenna is almost non-existent.

Signal detection: Because all audible signals fall within a frequency range of 20 Hz to 20 kHz, the signals from all sources stay densely mixed in the air. It will be difficult to distinguish or identify the broadcast signal at the receiving station since it would be distorted.

Consequently, modulation is required for a low-frequency signal when transferred to a remote location to prevent the information from being lost in the transmission process and for accurate identification of a signal while maintaining the antenna’s height to a minimum.

Conclusion 

Communication is the act of transmission of info. Every living creature within the world experiences the necessity to impart or receive information virtually unceasingly with alternatives in the close world. Communication pervades all stages of the lifetime of all living creatures. No matter its nature, each communication system has three essential elements: transmitter, medium/channel, and receiver. 

Thus, this can be all concerning the essential parts of the communication system. Therefore, the key elements of this method chiefly embody sources, input transducers, transmitter, communicating receiver, and the output transducer.