tsks01 digital communication lecture 1 - … · digital to analog analog ... linear system...
TRANSCRIPT
TS
KS
01 D
igital C
om
munic
ation
Lectu
re 1
Intr
od
uctio
n,
Re
pe
titio
n o
f S
&S
, C
ha
nn
el m
od
els
Mik
ae
l O
lofs
so
n
De
pa
rtm
en
t o
f E
E (
ISY
)
Div
. o
f C
om
mu
nic
atio
n S
yste
ms
20
12
-08
-31
TS
KS
01
Dig
ita
l C
om
mu
nic
ation
-L
ectu
re 1
2
TS
KS
01 D
igital C
om
munic
ation -
Form
alia
Info
rma
tio
n &
co
urs
e m
ate
ria
l:w
ww
.co
mm
sys.isy.liu
.se
/TS
KS
01
Le
ctu
rer
& e
xa
min
er:
Mik
ae
l O
lofs
so
n, m
ika
el@
isy.liu
.se
Pro
ble
m c
lasse
s a
nd
la
bs:
Mir
sa
dir
ki
, m
irsa
d@
isy.liu
.se
TV
K C
ha
ita
nya
, tv
k@
isy.liu
.se
Exa
min
atio
n:
La
bo
ratio
ns
(1h
p):
Tw
o 4
ho
ur
lab
ora
tio
ns
Sig
n-u
p o
n th
e w
eb
Wri
tte
ne
xa
m(5
hp
):
1 s
imp
le ta
sk �
De
ma
nd
: 1
/2
2 q
ue
stio
ns (
5 p
oin
ts e
ach
), m
in 3
4 p
rob
lem
s (
5 p
oin
ts e
ach
), m
in 6
Pa
ss: 1
4 p
oin
ts
20
12
-08
-31
TS
KS
01
Dig
ita
l C
om
mu
nic
ation
-L
ectu
re 1
3
Cours
e A
ims 1
(2)
Afte
r p
assin
g th
e c
ou
rse
, th
e s
tud
en
t sh
ou
ld
be
ab
le to
re
liab
ly p
erf
orm
sta
nd
ard
ca
lcu
latio
ns r
eg
ard
ing
dig
ita
l
mo
du
latio
n, b
ina
ry (
line
ar)
co
de
s fo
r e
rro
r co
ntr
ol a
nd
so
urc
e c
od
ing
.
(ba
sic
s)
be
ge
ne
rally
aq
ua
inte
d w
ith
mo
de
rn c
om
mu
nic
atio
n, e
sp
ecia
lly d
igita
l
co
mm
un
ica
tio
n, i.e
. b
e a
ble
to
brie
fly d
escrib
e s
eve
ral co
mm
un
ica
tio
n
tech
niq
ue
s.
(qu
es
tio
ns)
be
ab
le to
bri
efly a
cco
un
t fo
r so
me
co
mm
on
ch
an
ne
l m
od
els
,
esp
ecia
lly fo
r ca
ble
s, ra
dio
ch
an
ne
ls a
nd
op
tica
l ch
an
ne
ls.
(qu
es
tio
ns)
be
ab
le to
de
scrib
e p
rob
lem
s th
at a
rise
in
co
mm
un
ica
tio
n s
itu
atio
ns,
usin
g o
wn
wo
rds, a
nd
be
ab
le to
de
scri
be
, a
nd
in
a r
ele
va
nt w
ay,
co
mp
are
me
tho
ds to
co
un
tera
ct th
ose
pro
ble
ms.
(qu
es
tio
ns)
20
12
-08
-31
TS
KS
01
Dig
ita
l C
om
mu
nic
ation
-L
ectu
re 1
4
Cours
e A
ims 2
(2)
Afte
r p
assin
g th
e c
ou
rse
, th
e s
tud
en
t sh
ou
ld
be
ab
le to
acco
un
t fo
r th
e c
on
ne
ctio
n b
etw
ee
n d
iffe
ren
t co
nce
pts
in
the
co
urs
e in
a s
tru
ctu
red
wa
y u
sin
g a
de
qu
ate
te
rmin
olo
gy.
(qu
es
tio
ns)
be
ab
le to
, w
ith
so
me
pre
cis
ion
, a
na
lyze
an
d c
om
pa
re v
ari
ou
s c
ho
ice
s
of d
igita
l m
od
ula
tio
n m
eth
od
s a
nd
co
din
g m
eth
od
s in
te
rms o
f e
rro
r
pro
ba
bili
tie
s, m
inim
um
dis
tan
ce
s a
nd
re
late
d c
on
ce
pts
. (pro
ble
ms)
be
ab
le to
im
ple
me
nt su
ch
co
mm
un
ica
tio
n s
yste
ms th
at a
re tre
ate
d in
the
co
urs
e in
blo
ck fo
rm a
nd
em
pir
ica
lly e
va
lua
te th
em
. (la
bo
rati
on
s)
20
12
-08
-31
TS
KS
01
Dig
ita
l C
om
mu
nic
ation
-L
ectu
re 1
Languages in T
uto
rial S
essio
ns
Englis
h
Sw
edis
h
5
Englis
h
Sw
edis
h
The tuto
rial series s
chedule
d f
or
Gro
up_B
is c
ancelle
d.
All
teachin
g w
ill b
e in E
nglis
h.
20
12
-08
-31
TS
KS
01
Dig
ita
l C
om
mu
nic
ation
-L
ectu
re 1
6
Overv
iew
of a C
om
munic
ation S
ituation
Ch
an
ne
lS
en
de
r
Sa
mp
lin
g
Re
co
ns
tru
cti
on
D/A
-co
nve
rsio
n
Mo
du
lati
on
Ch
an
ne
l c
od
ing
So
urc
e c
od
ing
Fil
teri
ng
�
LT
I -
no
n L
TI
Fa
din
g
No
ise
Inte
nti
on
al
jam
min
g
�
So
urc
e s
tati
sti
cs
Sto
ch
as
tic
pro
ce
ss
Ma
rko
v c
ha
ins
Au
to-c
orr
ela
tio
n
�
De
ma
nd
s o
n q
ua
lity
Co
st
fun
cti
on
s
Ap
pli
ca
tio
n
Pu
rpo
se
�
Sa
mp
lin
g
Re
co
ns
tru
kti
on
A/D
-co
nve
rsio
n
De
mo
du
lati
on
Ch
an
ne
l-d
ec
od
ing
So
urc
e d
ec
od
ing
Fil
teri
ng
�
Re
ce
ive
rS
ou
rce
De
sti
na
tio
n
20
12
-08
-31
TS
KS
01
Dig
ita
l C
om
mu
nic
ation
-L
ectu
re 1
7
A O
ne-w
ay T
ele
com
munic
ation S
yste
m
Ch
an
ne
l
So
urc
e
en
co
de
r
So
urc
e
de
co
de
r
So
urc
e
De
sti
na
tio
n
Ch
an
ne
l
en
co
de
rM
od
ula
tor
Ch
an
ne
l
de
co
de
r
De
-
mo
du
lato
r
Sourc
e
codin
g
Channel
codin
g
Packin
g
Unpackin
g
Err
or
contr
ol
Err
or
corr
ection
Dig
italto
analo
g
Analo
g t
o d
igital
Mediu
m
Dig
ital
modula
tion
20
12
-08
-31
TS
KS
01
Dig
ita
l C
om
mu
nic
ation
-L
ectu
re 1
8
Cours
e C
onte
nts
Tra
nsm
issio
n c
ha
nn
els
(C
ab
les, R
ad
io, O
ptica
l)
(Le
ctu
res
1 &
4)
Intr
od
uctio
n to
sto
ch
astic p
roce
sse
s.
(Le
ctu
res
2-3
)
So
ftw
are
de
fin
ed
ra
dio
(la
b p
rep
ara
tio
n).
(Le
ctu
re 5
)
Co
mp
lex b
ase
ba
nd
re
pre
se
nta
tio
n.
(Le
ctu
re 6
)
Dig
ita
l m
od
ula
tio
n.
(Le
ctu
res
7-9
)
Co
de
s fo
r e
rro
r co
ntr
ol.
(Le
ctu
res
10
-11)
So
urc
e c
od
ing
(p
ackin
g d
ata
).
(Le
ctu
res
12
)
20
12
-08
-31
TS
KS
01
Dig
ita
l C
om
mu
nic
ation
-L
ectu
re 1
9
Repetition S
ignals
and S
yste
ms
Syste
mx(t)
y(t)
Sig
nals
:V
olt
ag
es, cu
rren
ts,
an
d o
ther
measu
rem
en
ts.
Syste
ms:
Man
ipu
late
sig
nals
.
Co
mp
lex e
xp
on
en
tial:
e
= c
os(2
f t) +
j s
in(2
f t)
Un
itste
p:
u(t)
=
Un
itim
pu
lse:
(t):
Pro
pert
y:
j 2
f t 0
0
0
0,
t<0
1,
t>0
x(t)
(t)
dt
= x
(0)
u(t
) =
()
d
t
20
12
-08
-31
TS
KS
01
Dig
ita
l C
om
mu
nic
ation
-L
ectu
re 1
10
Specia
l O
utp
uts
En
erg
y-f
ree
syste
m(t)
h(t)
Imp
uls
e r
esp
on
se
:
Ge
ne
ral ca
se
:
En
erg
y-f
ree
syste
mx(t)
y(t)
Ste
p r
esp
on
se
:
En
erg
y-f
ree
syste
mu(t)
g(t)
20
12
-08
-31
TS
KS
01
Dig
ita
l C
om
mu
nic
ation
-L
ectu
re 1
11
Lin
ear
Syste
m
20
12
-08
-31
TS
KS
01
Dig
ita
l C
om
mu
nic
ation
-L
ectu
re 1
12
Tim
e-I
nvariant and L
TI
20
12
-08
-31
TS
KS
01
Dig
ita
l C
om
mu
nic
ation
-L
ectu
re 1
13
Convolu
tion
20
12
-08
-31
TS
KS
01
Dig
ita
l C
om
mu
nic
ation
-L
ectu
re 1
14
Outp
ut of LT
I S
yste
ms
20
12
-08
-31
TS
KS
01
Dig
ita
l C
om
mu
nic
ation
-L
ectu
re 1
15
The F
requency d
om
ain
20
12
-08
-31
TS
KS
01
Dig
ita
l C
om
mu
nic
ation
-L
ectu
re 1
16
LT
I S
yste
ms
20
12
-08
-31
TS
KS
01
Dig
ita
l C
om
mu
nic
ation
-L
ectu
re 1
17
Cable
s
Ma
the
ma
tic
ally:
Lin
ea
rd
iffe
ren
tia
l e
qu
atio
n
LT
I syste
m, im
pu
lse
resp
on
se, fr
eq
ue
ncy
resp
on
se
Mo
de
l:
Tw
ow
ire
s:
y,
20
12
-08
-31
TS
KS
01
Dig
ita
l C
om
mu
nic
ation
-L
ectu
re 1
18
Chara
cte
ristic Im
pedance 1
(2)
Mo
de
lo
f a
n in
fin
ite
lylo
ng
ca
ble
:
Alte
rna
tive
mo
de
l:
So
lutio
n:
Re
su
lt:
Re
al p
art
ha
s to
be
po
sitiv
e:
with a
rgum
ent
in (
�/2
,/2
)
Als
oin
finitely
long
cable
20
12
-08
-31
TS
KS
01
Dig
ita
l C
om
mu
nic
ation
-L
ectu
re 1
19
Chara
cte
ristic Im
pedance 2
(2)
We
ha
d:
Serialpro
pert
ies
per
mete
r
Para
llelpro
pert
ies
per
mete
r
impedance
resis
tance
inducta
nce
adm
itta
nce
conducta
nce
capacitance
Po
ss
ible
ch
oic
e:
Re
su
lt:
Z
is r
ea
l a
nd
co
nsta
nt
Pro
pe
r te
rmin
ati
on
:
A fin
ite
ca
ble
sh
ou
ldb
e
term
ina
ted
with
th
e
imp
ed
an
ce
Z.
20
12
-08
-31
TS
KS
01
Dig
ita
l C
om
mu
nic
ation
-L
ectu
re 1
20
Fre
quency R
esponse o
f a C
able
1(2
)
Fin
ite
le
ng
thca
ble
:O
ne
lin
k:
Fre
qu
en
cy r
esp
on
se
of o
ne
lin
k:
Re
su
lt:
20
12
-08
-31
TS
KS
01
Dig
ita
l C
om
mu
nic
ation
-L
ectu
re 1
21
Fre
quency R
esponse o
f a C
able
2(2
)
Fre
qu
en
cy
resp
on
se
of a
on
em
ete
r lo
ng
ca
ble
:
An
am
ete
r lo
ng
ca
ble
:
Re
al-
va
lue
dch
ara
cte
ristic
imp
ed
an
ce
:
20
12
-08
-31
TS
KS
01
Dig
ita
l C
om
mu
nic
ation
-L
ectu
re 1
22
Lim
it for
the F
requency R
esponse
20
12
-08
-31
TS
KS
01
Dig
ita
l C
om
mu
nic
ation
-L
ectu
re 1
23
The T
ele
phone C
hannel
Du
e to
va
rio
us filt
ers
an
d m
od
ula
tio
ns in
te
lep
ho
ne
syste
ms.
Ap
pro
xim
ate
am
plit
ud
e c
ha
racte
ristic:
20
12
-08
-31
TS
KS
01
Dig
ita
l C
om
mu
nic
ation
-L
ectu
re 1
24
Optical F
ibers
Sp
ee
d o
f lig
ht
in v
acu
um
: c
3·1
08
m/s
Sp
ee
d o
f lig
ht
in o
the
r m
ed
ia:
v<
c
Re
fra
ctio
n in
de
x:
n=
c /
v
Exa
mp
les:
Air:
n1
.00
03
(
1)
Fib
er
gla
ss:
1.5
< n
< 1
.9 (
rou
gh
ly)
Se
nd
er
sid
eR
ece
ive
r sid
e
Lig
ht
sourc
eLig
ht
dete
cto
r
LE
D
Laser
Photo
dio
de
Photo
tra
nsis
tor
20
12
-08
-31
TS
KS
01
Dig
ita
l C
om
mu
nic
ation
-L
ectu
re 1
25
Ste
p-I
ndex F
iber
Acce
pta
nce
ha
lf-a
ng
le:
in =
arc
sin
Acce
pta
nce
fu
ll a
ng
le:
2in
Nu
me
rica
l a
pe
rtu
re:
sin
(in) =
n0
n12 �
n22
(
)
n0
n12 �
n22
20
12
-08
-31
TS
KS
01
Dig
ita
l C
om
mu
nic
ation
-L
ectu
re 1
26
Multim
ode P
ropagation
Diffe
ren
t p
ath
s -
d
iffe
ren
t d
ista
nce
s
d
iffe
ren
t d
ela
ys
p
uls
e s
pre
ad
ing
Lig
ht
pu
lse i
nL
igh
t p
uls
e o
ut
20
12
-08
-31
TS
KS
01
Dig
ita
l C
om
mu
nic
ation
-L
ectu
re 1
27
Multm
ode G
raded Index
20
12
-08
-31
TS
KS
01
Dig
ita
l C
om
mu
nic
ation
-L
ectu
re 1
28
Sin
gle
mode S
tep Index
ww
w.liu
.se