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Transmission Impairments - Coggle Diagram
Transmission Impairments
Transmission impairments
When a transmitted signal becomes distorted due to transmission impairments. For analog signals the quality can become degraded for digital signals bit errors can be introduced.
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Noise
Noise is the insertion of unwanted signals onto the transmission signal, its effect is to distort the signal during transmission. In particular effects of pulse impulses and thermal noise. It particularly affects digital signals. The greater noise, the greater the bit error rate.
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Thermal Noise
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The presence of thermal noise places an upper limit on the carrying capacity of a transmission system.
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Channel capacity
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Channel capacity allows us to study the interrelationships between signal bandwidth system bandwidth, and signal impairments.
Chanel capacity is the maximum rate at which data can be transmitted over a communications path or channel.
However, from the previous discussions channel capacity is that is limited. In practice by transmission impairments, of which the main constraint is noise.
Two distinguished scientists had something to say about this subject, namely Nyquist and Shannon.
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Limitation on channel capacity, it appears from Nyquist theorem, that any teacher ratio is achievable by.
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However, as a data rate increases, the bit error rate increases, it becomes more and more difficult for the receiver to distinguish different signal states.
noise and other transmission impairments put a practical limit on M and hence, on the maximum data rate achievable.
Noise and data rate
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The greater the noise, the greater the error rate for signal digital signals
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Shanon's Noisy channel
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Observations
Increasing the bandwidth increases the maximum data rate,
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Hence, the rate is limited by bandwidth and noise.
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