Tutorial 4
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Assume a data stream id made of ten 0s.
Encode this stream using the following
encoding schemes. How many changes
(vertical line) can you find for each scheme?
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Unipolar
Polar NRZ-L
Polar NRZ-I
Bipolar AMI
Pseudoternary
Manchester
Differential Manchester
B8ZS
HDB3
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Calculate the bit rate for the given baud
rate and type of modulation:
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1000
1000
1000
1000
baud,
baud,
baud,
baud,
FSK
ASK
8-PSK
16-QAM

Data from an analogue source ranges in value
between –1.0 to 1.0 volts. Assume a uniform
quantification of 8 bits. What binary values
(you may express the values in decimal)
correspond to the following source values?
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0.91 volts
-0.25 volts
0.5 volts
0.495 volts

Consider the transmission of a voice analog
signal (spectrum between 500 Hz and 4000
Hz) with a digital signal using PCM.
◦ Assuming samples are quantized using an 8-bit
code, what is the minimum data rate required to
transmit the voice signal?
◦ Given M=2 (2 levels in the digital signal), use
Nyquists formula to determine the medium
bandwith necessary to support the transmission of
the signal.
◦ Determine the level of quantizing noise (decibel).