Software Development Life Cycle By Team Orange (Dept. of Pharmacy)
class 5
1. (Note on class topic )
Base & Broad , Transmisson impairment
Course Title: Data Communication
Course Code: CSE 313
Submitted To Submitted by
Pronab nath bondhu Fairuz Fatemi
Lecturer ID:1834902087
City University Batch:49(B)Day
B.S.C in CSE
D:06/09/2021
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2. Transmission Impairment
In the data communication system, Analog and digital signals go through
the transmission medium. Transmission media are not ideal. So, the
signals sent through the transmission medium are also not perfect.
A. For a digital signal, there may occur bit errors.
B. For Analog signals, these impairments degrade the quality of the
signals.
There are three main causes of impairment are,
1. Attenuation
2. Distortion
3. Noise
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3. 1) Attenuation
• That is why a wire carrying electrical signals gets warm, if not hot, after a while.
Some of the electrical energy is converted to heat in the signal.
• Amplifiers are used to amplify the signals to compensate for this loss.
• This figure shows the effect of attenuation and amplification:
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4. 2) Distortion
• Each component of frequency has its propagation speed traveling through a
medium and therefore, different components have different delay in arriving at the
final destination.
• It means that signals have different phases at the receiver than they did at the
source.
• This figure shows the effect of distortion on a composite signal:
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5. 3) Noise
• Noise is another problem. There are some random or unwanted
signals mix up with the original signal is called noise.
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Different types of noises are:
a.Thermal noise
b.Intermodulation noise
c.Crosstalk
d.Impulse noise
6. Baseband and Broadband
• Broadband system use modulation techniques to reduce the effect of noise in the
environment. Broadband transmission employs multiple channel unidirectional
transmission using combination of phase and amplitude modulation.
• Baseband is a digital signal is transmitted on the medium using one of the signal
codes like NRZ, RZ Manchester biphase-M code etc. is called baseband
transmission.
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7. Differences between baseband and broadband :
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No Baseband
Broadband
1. Baseband Transmission is bidirectional in nature. Broadband Transmission is unidirectional in nature.
2. Signals can only travel over short distances.
Signals can be travelled over long distances without
being attenuated.
3. It works well with bus topology. It is used with a bus as well as tree topology.
4.
In baseband transmission, Manchester and
Differential Manchester encoding are used.
Only PSK encoding is used.
