While designing a communication system , an engineer generally faces several constraints or limitations. These are noise limitation, bandwidth limitation and equipment limitation.
1) Noise Limitation:-
The noise may be defined as an unwanted form of energy which tend to interfere with the transmission and reception of the desired signals in a communication system.The noise cannot be eliminated completely. However , the effect of noise on desired signals can be minimised with the help of several techniques. noise can be classified into two broad categories depending upon its source:
1.External noise
2.Internal noise
External noise is that type of noise are atmospheric noise , galactic noise and industrial noise.
Internal noise is that type of noise whose sources are internal to a communication system. For examples of internal noise are thermal noise and shot noise. This type of noise is inevitable in every communication system and forms a basic limitation on transmission and reception of signals.
2) Bandwidth Limitation:-
The bandwidth limitation is another major constraint in a communication system. The frequency range and the band of the frequency needed for a particular given transmission is known as bandwidth. This band of frequencies required for a particular transmission is also called channel. This type of regulation is essential to avoid interference among the signals having same frequency. This allocated bandwidth may not be sufficient to convey the entire information.
3) Equipment Limitation:-
This noise and bandwidth limitations indicate theoretically what can or cannot be achieved in terms of performance in a communication system. This theoretical limit may not be realised in a practical system due to equipment limitations.
For example , the theory might require a band pass filter with a quality factor of 100 at a center frequency of 1khz. Such a filter can not be realised in practice. If a filter with nearly identical characteristics is built , the cost may exceed what the user of the communication system wants to play. Thus equipment limitation is another major problem in a communication system.
1) Noise Limitation:-
The noise may be defined as an unwanted form of energy which tend to interfere with the transmission and reception of the desired signals in a communication system.The noise cannot be eliminated completely. However , the effect of noise on desired signals can be minimised with the help of several techniques. noise can be classified into two broad categories depending upon its source:
1.External noise
2.Internal noise
External noise is that type of noise are atmospheric noise , galactic noise and industrial noise.
Internal noise is that type of noise whose sources are internal to a communication system. For examples of internal noise are thermal noise and shot noise. This type of noise is inevitable in every communication system and forms a basic limitation on transmission and reception of signals.
2) Bandwidth Limitation:-
The bandwidth limitation is another major constraint in a communication system. The frequency range and the band of the frequency needed for a particular given transmission is known as bandwidth. This band of frequencies required for a particular transmission is also called channel. This type of regulation is essential to avoid interference among the signals having same frequency. This allocated bandwidth may not be sufficient to convey the entire information.
3) Equipment Limitation:-
This noise and bandwidth limitations indicate theoretically what can or cannot be achieved in terms of performance in a communication system. This theoretical limit may not be realised in a practical system due to equipment limitations.
For example , the theory might require a band pass filter with a quality factor of 100 at a center frequency of 1khz. Such a filter can not be realised in practice. If a filter with nearly identical characteristics is built , the cost may exceed what the user of the communication system wants to play. Thus equipment limitation is another major problem in a communication system.
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