What is a Communication System?
The communication system is a system model that describes a communication exchange between two stations, transmitter, and receiver. Signals or information passes from source to destination through a channel. It represents a way in which the signal uses it to move from a source toward its destination. To transmit signals in a communication system, it should first be processed by beginning from signal representation, to signal shaping until encoding and modulation. After the transmitted signal is prepared, it is passed to the transmission line of the channel. Due to signal crossing this media, it is faced with many impairments like noise, attenuation, and distortion.
The process of transferring the information between two points is called communication. The main elements needed to communicate are the transmitter to send the information, the medium to send the information and the receiver to receive the information on the other end.
Types of Communication Systems
Based on physical infrastructure:
Based on physical infrastructure there are two types of communication systems:
Line communication systems: Uses the existing infrastructure of power lines to transfer data from one point to another point.
Radio Communication systems: uses the infrastructure of radio waves to transfer the information from one point to another point.
There is a physical link, called a hardwire channel between the transmitter and the receiver inline communication systems.
Based on Signal specifications:
Signal specifications that are used to decide the type of communication system are:
Nature of the baseband or information signal: Baseband signals is a technology which can access the signals with very low frequency and also near zero frequency and based on the nature of the transmitted signal, the baseband signal can either be transmitted as it is without modulation or through a carrier signal with modulation.
Further, communication systems are divided into:
Analog communication systems: The Analog system conveys the information from the audio, video and pictures between two points using the analogue signals. A sinusoidal signal is an example of an analogue communication system.
Digital communication systems: Digital communication has become very important in the age of the internet. It is a physical exchange of information between two points discreetly. The information exchange happens through digital signals.
Baseband communication system: Baseband communication is the transfer of signals that are not amplified to higher frequencies. They help in transferring signals with near-zero frequency.
Carrier communication system: Carrier communication systems transfer the information especially voice messages and calls by improving the frequency much higher than the actual rate.
Out of four, a minimum of two types is needed to specify any communication system. Thus, two groups are formed consisting of each of the two types such that at least one of the types from each group is necessarily required to specify a communication system. These groups can be formed as:
Analog/digital communication systems
Baseband/carrier communication systems
To completely define any communication system, four out of the eight types are required. If any type is missing, then the description of the communication system will be incomplete.
Wireless and Wired communication system
Wireless communication systems use radio waves, electromagnetic waves and infrared waves to communicate from one point to another point and the wire communication system uses wire, optical fibre which works on the phenomenon of total internal reflection to communicate from one point to another point.
Wireless communication is further divided into satellite communication, ground wave communication, skywave and space wave communication. The satellite communication receives the signals from the earth and resends them back to another point on the earth with the help of a transponder. Wired communication is further divided into parallel wire, twisted wire, optical fibre and coaxial wired communication.
Terms Used in Communication Systems
1. Signal
A signal is that information that has been converted into a digital format. Analog signals (such as human voice) or digital signals (binary data) are inputted to the system, processed within the electronic circuits for transmission, then decoded by the receiver. The system is claimed to be reliable and effective; only errors are minimized within the process.
2. Communication Channel
A communication channel is a medium by which a signal travels.
3. Transducer
The device used to convert one form of energy into another form is a transducer.
4. Receiver
A receiver is a device that receives the signals sent/ transmitted by the senders and decodes them into a form that is understandable by humans.
5. Attenuation
Attenuation is the reduction in the strength of analog or digital signal as it is transmitted over a communication medium.
6. Amplitude
An amplitude of the signal refers to the strength of the signal.
7. Amplification
Amplification is the process to strengthen the amplitude of the signals using an electronic circuit.
8. Bandwidth
Bandwidth explains the range of frequency over which a signal has been transmitted.
9. Modulation
As the original message signal can't be transmitted over an outsized distance due to their low frequency and amplitude, they're superimposed with high frequency and amplitude waves called carrier waves. This phenomenon of superimposing a message signal with a carrier wave is called modulation. And the resultant wave is a modulated wave which is to be transmitted.
Different Types of Modulation.
Amplitude Modulation (AM)
Frequency Modulation (FM)
Phase Modulation (PM)
10. Demodulation
Demodulation takes a modulated signal and then extracts the original message from it.
11. Repeater
The repeater extends the range of communication systems by amplifying the signals.
12. Noise
Any electrical signal which interferes with an information signal is called noise.
Did You Know?
Communication Is Related To Every Human Activity.
Communication in Organization Flows in Various Patterns.
Communication Is Media or Channel Based
There are around 250 billion emails sent every day. Around 80% of these are spam.
Around 20 hours of video are uploaded to YouTube every minute.
Fiber optics are good because they use less energy and are better for the environment than electrical wires. They are also very resistant to weather.
The first telephone pole was built in 1876.
There are over 4 billion cell phones within the world and phones that are thrown away every year are over 100 million.
The first cell phone was invented by a company called Motorola.
Over 3.8 billion people use the internet, which is 40% of the world's population.
The first smiley appeared in 1979, it first looked like this -) then three years later a colon was added to it and it took the form of :-) this.
FAQs on Communication Systems
1. What is a Duplex Communication System?
The system that has two connected devices that are able to communicate with each other in both directions is called a duplex communication. The duplex term is used while describing communication between two parties or devices. Duplex systems are employed in almost all communications networks. An Antenna is basically a small length of a qwerty conductor that is used to radiate or receive electromagnetic waves. It acts as a conversion device. At its transmitting end, it can convert a current of high frequency into electromagnetic waves. At the receiving end, it transforms electromagnetic waves into electrical signals that are fed into the input of the receiver.
2. What is a Communication Channel? Explain in Detail.
A communication channel is a medium by which a signal travels. There are two types of media by which electrical signals travel - guided and unguided. Guided media is a medium that is directed from transmitter to receiver by means of connecting cables. Guided media includes coaxial cables, telephone wire, twisted-pairs, etc. The other type of media is unguided media referring to any communication channel which creates space between the transmitter and receiver. For radio communication, the air is the only medium between the transmitter and the receiver. Communication channels include everything from the vacuum of space to solid pieces of metal.
3. Explain wired and wireless communication in detail?
Communication is the transfer of information from one place to another place. It needs three main elements, a transmitter to send the information in the forms of signals, a medium to pass the information and a receiver on the other end to receive the information.
Wired and wireless are two types of communications based on the device used. Wired communication needs wires to connect the power source and the device. It is of four types namely, parallel wire, twisted wire, optical fibre and coaxial wired communication. This type of communication is also known as line communication. Wireless communication is the transfer of information between two points without the use of an electric conductor as a medium. It is also of the following types namely satellite communication, ground wave communication, skywave and space wave communication.
4. What is a communication system and what are its examples?
Communication is the exchange of information between two points. The system which describes this process is called the communication system. There are three major elements in communication namely, the receiver, to send the information. Medium to pass the information through it and finally receiver to receive the information. Following are the examples of the communication system:
The Internet is a system of connected computers, mobiles, laptops etc., globally. Every device is traced using an IP address also known as internet protocol address
A public switched telephone network also known as PSTN is an aggregate of telephone networks. They are operated by telephone operators, locally, nationally and regionally.
Intranet is a secured private connection a company uses to communicate within the organisation and to limited people. On the other hand, the extranet is similar to that of the intranet but also connects to external sources limitedly. For example, connecting with the suppliers and customers.
Television is a device used to cast audio and video information. It works with the help of a transmitter and local area operator. It is considered to be one of the major revolutions in communication technologies.
5. What are the elements of communication systems?
communication system is a system that facilitates the exchange of information between two points. It has three basic elements namely, the transmitter, the medium of exchange and the receiver on the other end, signal, transducer, amplifier, modulator, antenna, noise etc.,
Information is the message that has to be transferred throughout the medium to the other end. It could be in any format like audio, video etc.,
The information which is in raw format is converted to electric format and sent in the form of signals to the receiver through the medium
To convert energy or information from one format to another format, a transducer is used. An electric transducer converts information from audio, video, pressure format to electric signals.
To improve the strength of the signals transmitting the information, an amplifier is used. It can be placed anywhere in between the receiver and transmitter
Original messages converted into signals can not be transferred to a greater distance. A modulator is used to superimpose the signals and increase the frequency of transmission, finally permitting the information to send it to greater distances.
