... iEE
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Digital Communications I:
Modulation and Coding Course
Period 3 - 2007
Catharina Logothetis
Lecture 5
Lecture 5 20
Eb/No figure of merit in digital
communications
... symbol.
b
bb
R
W
N
S
WN
ST
N
E
==
/
0
b
R
W
: Bit rate
: Bandwidth
Lecture 5 21
Example of Symbol error prob. For PAM
signals
)(
1
t
ψ
0
1
s
2
s
b
E
b
E−
Binary PAM...
... iEE
sii
s
s
ski
Ed
ki
Ed
2
2
min
,
=
≠
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Digital Communications I:
Modulation and Coding Course
Term 3 - 2008
Catharina Logothetis
Lecture 5
Lecture 5 20
Eb/No figure of merit in digital
communications
SNR ... symbol.
b
bb
R
W
N
S
WN
ST
N
E
==
/
0
b
R
W
: Bit rate
: Bandwidth
Lecture 5 21
Example of Symbol error prob. For PAM
signals
)(
1
t
ψ
0
1
s
2
s
b
E
b
E−
Binary PA...
... error detection and correction codes
Lecture 9 7
Why using error correction coding?
Error performance vs. bandwidth
Power vs. bandwidth
Data rate vs. bandwidth
Capacity vs. bandwidth
(dB) ...
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p
Digital Communications I:
Modulation and Coding Course
Period 3 - 2...
... signal
Baseband versus bandpass:
Bandwidth dilemma:
Bandlimited signals are not realizable!
Realizable signals have infinite bandwidth!
Baseband
signal
Bandpass
signal
Local oscillator
Lecture ... oscillator
Lecture 1 25
Bandwidth of signal …
Different definition of bandwidth:
a) Half-power bandwidth
b) Noise equivalent bandwidth
c) Null-to-null bandwidth
a) Fractional power...
... I:
Modulation and Coding Course
Period 3 – 200/
Catharina Logothetis
Lecture 2
Lecture 2 10
Encoding (PCM)
A uniform linear quantizer is called Pulse Code
Modulation (PCM).
Pulse code modulation ... concepts and definitions as signal
classification, spectral density, random
process, linear systems and signal bandwidth.
Lecture 2 20
Spectra of PCM waveforms
Lecture...