Telecommunication systems
Lecturer: M.Eng. P.T.A.Quang
Quality of service and telecommunication
impairments
1. Quality of service: voice, data, and image
2. The three basic impairments and how they affect the
end-user
3. Level
4. Echo and singing
Quality of service : voice, data, and image
SNR
Voice transmission
Data circuits
Video
Signal-to-Noise ratio
Measure signal quality
S/N requirement (@ receivers):
Voice: 40 dB
Video (TV): 45 dB
Data: 15dB (depend on modulation type and specified error
performance)
N
S
SNR
Voice transmission
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