chuong 2- tin & luong tin
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7/17/2019 Chuong 2- Tin & Luong Tin
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LYÙ THUYEÁT TRUYEÀN TINLYÙ THUYEÁT TRUYEÀN TIN
CHÖÔNG 2:CHÖÔNG 2:
TIN VAØ LÖÔÏNG TIN TIN VAØ LÖÔÏNG TIN
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Noäi dung c!n cu"# c$%ngNoäi dung c!n cu"# c$%ng
22&'&' Tin ($)c Tin ($)c
2'2' L$%*ng (inL$%*ng (in
+'+' ,oä -#.( /0n cu"# nguo1n (in,oä -#.( /0n cu"# nguo1n (in'' To.c /oä 3#ä4 (in To.c /oä 3#ä4 (in
5'5' To6ng 3$%*ng 786n To6ng 3$%*ng 786n
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&' Tin ($)c&' Tin ($)c
Nguo1n (in 3#9 n%i 4#)( # (in ($)c' Tin ($)c /$%*cNguo1n (in 3#9 n%i 4#)( # (in ($)c' Tin ($)c /$%*c4#)( # 3#9 ;oä( <u#) (=n ng#>u ni86n'4#)( # 3#9 ;oä( <u#) (=n ng#>u ni86n'
?oä( -#"n (in cu* (8@ 3#9 ;oä( (8@ i8än cu"#?oä( -#"n (in cu* (8@ 3#9 ;oä( (8@ i8än cu"#<u#) (=n ng#>u ni86n /o)'<u#) (=n ng#>u ni86n /o)'
Tin ($)c co) #i 3o#*i: Tin ($)c co) #i 3o#*i:o Tin ($)c 3i86n (u*c Tin ($)c 3i86n (u*co Tin ($)c %9i #*c' Tin ($)c %9i #*c'
?oä( -#"n (in 3i86n (u*c o#9n (o#9n ($%ng /$%ng?oä( -#"n (in 3i86n (u*c o#9n (o#9n ($%ng /$%ng%)i ;oä( -#"n (in %9i #*c <u# /0n 3B) 3#.B ;#>u%)i ;oä( -#"n (in %9i #*c <u# /0n 3B) 3#.B ;#>u#nnon#nnon
V= #äBD /8@ /%n gi#"nD (# c F8)( (in ($)c %9i #*c'V= #äBD /8@ /%n gi#"nD (# c F8)( (in ($)c %9i #*c'
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Tin ($)c Tin ($)c
T#.( c#" c#)c -#"n (in cu"# ;oä( nguo1n (in T#.( c#" c#)c -#"n (in cu"# ;oä( nguo1n (in/81u /$%*c (#9n 3#ä4 ($9 ;oä( -oä 7B)/81u /$%*c (#9n 3#ä4 ($9 ;oä( -oä 7B)i8äu B;-o3 cu"# nguo1n (in /o)'i8äu B;-o3 cu"# nguo1n (in /o)'
Go*i -oä 7B) i8äu n#9B 3#9Go*i -oä 7B) i8äu n#9B 3#9 AAD #9 gi#" $"D #9 gi#" $"-oä 7B) i8äu co) ; 7B) i8äu:-oä 7B) i8äu co) ; 7B) i8äu: ##&&D #D #22D D #D D #;;'' T# co): T# co):
A J K#A J K#iiD iJ&'';D iJ&''; ?oä( -#"n (in?oä( -#"n (in MM 3#9 d#B c#)c 7B) i8äu3#9 d#B c#)c 7B) i8äu #i#i
/$%*c F#O4 F8.4 (8o ;oä( ($) ($* n#9o /o):/$%*c F#O4 F8.4 (8o ;oä( ($) ($* n#9o /o):MJ FMJ F&&D FD F22D D FD D Fnn FFii € A € A
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Tin ($)c Tin ($)c
V! du &: Ti8.( -0 4#)( (!n i8äu ?o8 $"V! du &: Ti8.( -0 4#)( (!n i8äu ?o8 $"du*ng (ong /i8än -#)o:du*ng (ong /i8än -#)o:o Nguo1n (in A co) + 7B) i8äu 3#9: PNguo1n (in A co) + 7B) i8äu 3#9: P''QD PQD P QD P QQD P Q
7o#"ng (#Ong7o#"ng (#OngS T$)c 3#9 # T$)c 3#9 #&& J PJ P''QD #QD #22 J PJ P QD #9 #QD #9 #++ J PJ P QQ
o Gi#" $" nguo1n (in n#9B 4#)( # -#"n (in:Gi#" $" nguo1n (in n#9B 4#)( # -#"n (in:S M J ' M J ' c$ A'c$ A'
#"n (in n#9B co): F#"n (in n#9B co): F&& J P'QD FJ P'QD F22 J PQJ PQS MJ ' ' 'MJ ' ' ' c$ 'c$ '
#"n (in n#9B co): F#"n (in n#9B co): F&& J PQD FJ PQD F22 J P'QD FJ P'QD F++ J P'QD FJ P'QD F J P'QJ P'QS MJ ' ' ' ' MJ ' ' ' ' c$ A'c$ A'
#"n (in n#9B co): F#"n (in n#9B co): F&& J PQD FJ PQD F22 J P'QD FJ P'QD F++ J P'QD FJ P'QD F J P'QJ P'Q
FF55 J P QD FJ P QD F J P'QD FJ P'QD F J PQJ PQ
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Tin ($)c Tin ($)c
V! du* 2: ?#)B /i8än (o*#i di /oängV! du* 2: ?#)B /i8än (o*#i di /oängn#On (in c#)c (in (i8.ng An:n#On (in c#)c (in (i8.ng An:
o Nguo1n (in A go1; c#)c 7B) i8äu 3#9: #D -DNguo1n (in A go1; c#)c 7B) i8äu 3#9: #D -DcD D WD XD &D D #9 c#)c d#.u'cD D WD XD &D D #9 c#)c d#.u'S T$)c 3#9 # T$)c 3#9 #&& J P#QD #J P#QD #22 J P-QD #J P-QD #++ J PcJ Pc QD #2 J PWQD #2 J PW
o Gi#" $" nguo1n (in n#9B 4#)( # -#"n (in:Gi#" $" nguo1n (in n#9B 4#)( # -#"n (in:S M J di uong c#Z8M J di uong c#Z8
#"n (in n#9B co): F#"n (in n#9B co): F&& J PdQD FJ PdQD F22 J PiQD FJ PiQD F++ J PJ PQD FQD F J PuQD J PuQD
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Tin ($)c Tin ($)c
,o.i %)i ng$%9i n#än (inD 7i /o@i co> c#)c,o.i %)i ng$%9i n#än (inD 7i /o@i co> c#)c7B) i8äu %)i n#uD noäi dung (in (#B /o@i'7B) i8äu %)i n#uD noäi dung (in (#B /o@i'
V%)i 8ä (o.ng (uB81n (inD 7i /o@i co>DV%)i 8ä (o.ng (uB81n (inD 7i /o@i co>Do. 3#1n Fu#.( i8än cu"# c#)c 7B) i8äu 3#9o. 3#1n Fu#.( i8än cu"# c#)c 7B) i8äu 3#97o6ng /o@i #9 7o6ng #"n $%"ng (%)i7o6ng /o@i #9 7o6ng #"n $%"ng (%)i<u#) (=n (uB81n (in'<u#) (=n (uB81n (in'
M8)( (86n <u#n /i8@; (uB81n (inD (# cM8)( (86n <u#n /i8@; (uB81n (inD (# c<u#n (#6; (%)i 7#" n#[ng Fu#.( cu"# c#)c<u#n (#6; (%)i 7#" n#[ng Fu#.( cu"# c#)c7B) i8äu (ong -#"n (in ;#9 7o6ng <u#n7B) i8äu (ong -#"n (in ;#9 7o6ng <u#n(#6; (%)i 0 (! cu"# ($9ng 7B) i8äu'(#6; (%)i 0 (! cu"# ($9ng 7B) i8äu'
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Tin ($)c Tin ($)c
N$ #äBD ;oä( nguo1n (in co) (8@ /$%*cN$ #äBD ;oä( nguo1n (in co) (8@ /$%*c;o6 (#" -#\ng -oä 7B) i8äu;o6 (#" -#\ng -oä 7B) i8äu AJK#AJK#iiD iJ&'';D iJ&'';
#9 F#)c u#.( Fu#.( i8än c#)c 7B) i8äu#9 F#)c u#.( Fu#.( i8än c#)c 7B) i8äu/o)/o) 4#4#ii''
]B) i8äu nguo1n:]B) i8äu nguo1n: KAD 4#KAD 4#iiD iJ&'';D iJ&''; ?oä( 48)4 -i8.n /o@i (o@ng <u#)( (ong 8ä?oä( 48)4 -i8.n /o@i (o@ng <u#)( (ong 8ä
(o.ng (uB81n (in 3#9 48)4 -i8.( /o@i ($9(o.ng (uB81n (in 3#9 48)4 -i8.( /o@i ($9-oä 7B) i8äu n#9B #ng -oä 7B) i8äu 7#)c:-oä 7B) i8äu n#9B #ng -oä 7B) i8äu 7#)c:
KAD 4#KAD 4#iiD iJ&'';D iJ&''; ^_^_ KD 4-KD 4- ` `D `J&''nD `J&''n
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Tin ($)c Tin ($)c
V! du* &: a#)( (!n i8äu ?o8 ($*c c#.(V! du* &: a#)( (!n i8äu ?o8 ($*c c#.(3#9 48)4 -i8.n3#9 48)4 -i8.n
o T$9 -oä 7B) i8äu: T$9 -oä 7B) i8äu: KbAD bD ' ' ' D bD bXD b&D' ' 'DKbAD bD ' ' ' D bD bXD b&D' ' 'Dbbo e#ng -oä 7B) i8äu:e#ng -oä 7B) i8äu: Kb'D bD b bKb'D bD b b
Tu (!n i8äu ?o8 3#9 48)4 -i8.n /o@i Tu (!n i8äu ?o8 3#9 48)4 -i8.n /o@i
ng$%*c 3#*i:ng$%*c 3#*i:o T$9 -oä 7B) i8äu: T$9 -oä 7B) i8äu: Kb'D bD b bKb'D bD b bo e#ng -oä 7B) i8äu:e#ng -oä 7B) i8äu:KbAD bD ' ' ' D bD bXDKbAD bD ' ' ' D bD bXD
b&D' ' 'D bb&D' ' 'D b
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Tin ($)c Tin ($)c
V! du* 2: a8)4 ;# o#) (ong c% c#.uV! du* 2: a8)4 ;# o#) (ong c% c#.u-i8.n /o@i Af (!n i8äu (o#*i:-i8.n /o@i Af (!n i8äu (o#*i:
o T$9 -oä 7B) i8äu: T$9 -oä 7B) i8äu: 25 ;$)c 3$%*ng ($"D ;o>i #25 ;$)c 3$%*ng ($"D ;o>i # ii 3#9 ;oä( ;$)c 3$%*ng ($"3#9 ;oä( ;$)c 3$%*ng ($"o e#ng -oä 7B) i8äu:e#ng -oä 7B) i8äu: KbXD b&KbXD b&
a8)4 gi#"i ;# (ong c% c#.u -i8.n /o@ia8)4 gi#"i ;# (ong c% c#.u -i8.n /o@i
fA (!n i8äu (o#*i 3#9 48)4 -i8.n /o@ifA (!n i8äu (o#*i 3#9 48)4 -i8.n /o@ing$%*c 3#*i:ng$%*c 3#*i:o T$9 -oä 7B) i8äu: T$9 -oä 7B) i8äu: KbXD b&KbXD b&o e#ng -oä 7B) i8äu:e#ng -oä 7B) i8äu: 25 ;$)c 3$%*ng ($"25 ;$)c 3$%*ng ($"
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L$%*ng /o (in ($)c 3$%*ng (inL$%*ng /o (in ($)c 3$%*ng (in
H8ä (o.ng (uB81n (in c <u#n (#6; (%)iH8ä (o.ng (uB81n (in c <u#n (#6; (%)i7#" n#[ng Fu#.( i8än ;#9 7o6ng <u#n7#" n#[ng Fu#.( i8än ;#9 7o6ng <u#n(#6; (%)i ($) ($* Fu#.( i8än c#)c cu"# c#)c(#6; (%)i ($) ($* Fu#.( i8än c#)c cu"# c#)c7B) i8äu #7B) i8äu #ii''
?oä( (in?oä( (in c#9ng !( Fu#.( i8än c#9ng co) gi#)c#9ng !( Fu#.( i8än c#9ng co) gi#)(0(0''
Tin Tin Fu#.( i8än c#9ng ni81u c#9ng !( gi#) (0Fu#.( i8än c#9ng ni81u c#9ng !( gi#) (0'' ,8@ /#)n gi#) gi#) (0 cu"# (inD ng$%9i (# /$#,8@ /#)n gi#) gi#) (0 cu"# (inD ng$%9i (# /$#
# 7#)i ni8ä;# 7#)i ni8ä; 3$%*ng /o (in ($)c3$%*ng /o (in ($)c 3$%*ng (in3$%*ng (in''
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,0n ngh# 3$%*ng (in,0n ngh# 3$%*ng (in
L$%*ng (in cu"# ;oä( 7B) i8äu #i 3#9L$%*ng (in cu"# ;oä( 7B) i8äu #i 3#9;oä( #9; I#;oä( #9; I#iiD 4u* (uoäc #9o 7#"D 4u* (uoäc #9o 7#"
n#[ng Fu#.( i8än cu"# 7B) i8äu /o):n#[ng Fu#.( i8än cu"# 7B) i8äu /o):
o N8.u c% o. 3#9N8.u c% o. 3#9 88 (= ($) nguB86n 3#9(= ($) nguB86n 3#9 n#(n#(o N8.u c% o. 3#9N8.u c% o. 3#9 &X&X (= ($) nguB86n 3#9(= ($) nguB86n 3#9
H#38BH#38Bo N8.u c% o. 3#9N8.u c% o. 3#9 22 (= ($) nguB86n 3#9(= ($) nguB86n 3#9 -i(-i(
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L$%*ng (in i86ngL$%*ng (in i86ng
Co nguo1n (in KADa#Co nguo1n (in KADa#iiD iJ&'';D iJ&''; L$%*ng (in c$)# (ong ;o>i ;o>i (in #L$%*ng (in c$)# (ong ;o>i ;o>i (in #ii
/$%*c go*i 3#9 3$%*ng (in i86ng cu"# (in/$%*c go*i 3#9 3$%*ng (in i86ng cu"# (in/o):/o):
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L$%*ng (in i86ngL$%*ng (in i86ng
V! du* &V! du* &: ?oä( nguo1n (in go1; co) -o.n 7B): ?oä( nguo1n (in go1; co) -o.n 7B)i8äu (in 3#9 KXXD X&D &XD && /#ng F#)ci8äu (in 3#9 KXXD X&D &XD && /#ng F#)cu#.('u#.('o T$)c 3#9 a# T$)c 3#9 a#&& J a# J a#22 J a# J a#++ J a# J a#J&fJ&fo V#äBV#äB I#I#&& J I# J I#22 J I# J I#++ J I# J I#J 3ogJ 3og22 &f&fJ2 -i(&f&fJ2 -i(
V! du* 2V! du* 2: ?oä( nguo1n (in go1; co) j 7B) i8äu: ?oä( nguo1n (in go1; co) j 7B) i8äu
(in 3#9 KXXXD XX&D D &&& /#ng F#)c(in 3#9 KXXXD XX&D D &&& /#ng F#)cu#.('u#.('o T$)c 3#9 a# T$)c 3#9 a# ii J &fj J &fj iJ&''jiJ&''j
o V#äBV#äB I#I#ii J 3og J 3og22 &f&fjJ+ -i(&f&fjJ+ -i( iJ&''jiJ&''j
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L$%*ng (in i86ngL$%*ng (in i86ng
V! du* +V! du* +: ?oä( nguo1n (in go1; co) #i: ?oä( nguo1n (in go1; co) #i7B) i8äu (in 3#9 KXD & /#ng F#)c7B) i8äu (in 3#9 KXD & /#ng F#)c
u#.('u#.('o T$)c 3#9 a# T$)c 3#9 a#&& J a# J a#22 J&f2 J&f2
o V#äBV#äB I#I#&& J I# J I#22 J 3og J 3og22 &f&f2J& -i(&f&f2J& -i(
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L$%*ng (in i86ngL$%*ng (in i86ng
V! du* V! du* : ?oä( nguo1n (in go1; co) -#: ?oä( nguo1n (in go1; co) -#7B) i8äu (in 3#9 KXD &XD&& co)7B) i8äu (in 3#9 KXD &XD&& co)
F#)c u#.( n$ #u:F#)c u#.( n$ #u:o abX J kl a&X J&fl a&&J&fabX J kl a&X J&fl a&&J&fo T=; 3$%*ng (in i86ng cu"# ($9ng (inm T=; 3$%*ng (in i86ng cu"# ($9ng (inm
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L$%*ng (in i86ngL$%*ng (in i86ng
V! du* 5V! du* 5: ?oä( nguo1n (in go1; co): ?oä( nguo1n (in go1; co)c#)c 7B) i8äu (in 3#9 KXDc#)c 7B) i8äu (in 3#9 KXD
&XD&&XD&&& co) F#)c u#.( n$&XD&&XD&&& co) F#)c u#.( n$#u:#u:o abX J kl a&X J&fl a&&XJ&fjlabX J kl a&X J&fl a&&XJ&fjl
a&&&J&fja&&&J&fj
o T=; 3$%*ng (in i86ng cu"# ($9ng (inm T=; 3$%*ng (in i86ng cu"# ($9ng (inm
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L$%*ng (in i86ngL$%*ng (in i86ng
V! du* V! du* : ?oä( nguo1n (in go1; co): ?oä( nguo1n (in go1; co)c#)c 7B) i8äu (in 3#9 K#&D#2D #+D #Dc#)c 7B) i8äu (in 3#9 K#&D#2D #+D #D
#5D#D # co) F#)c u#.( n$ #u:#5D#D # co) F#)c u#.( n$ #u:o a#& J &fl a#2 J&fjl a#+J&fjla#& J &fl a#2 J&fjl a#+J&fjla#J&fja#J&fj
a#5 J &f&l a# J&f&l a#J&fa#5 J &f&l a# J&f&l a#J&f
o T=; 3$%*ng (in i86ng cu"# ($9ng (inm T=; 3$%*ng (in i86ng cu"# ($9ng (inm
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L$%*ng (in ($%ng o>L$%*ng (in ($%ng o>
Tong (uB81n (inD n8.u 786n (uB81n 3#9 Tong (uB81n (inD n8.u 786n (uB81n 3#93B) ($%"ngD (# 8 co) $* -i8.n /o@i 3B)3B) ($%"ngD (# 8 co) $* -i8.n /o@i 3B)
($%"ng ($9 nguo1n KAD 4#iD iJ&''n #ng($%"ng ($9 nguo1n KAD 4#iD iJ&''n #ngnguo1n KD4-iD iJ&''n 3#9 &^&nguo1n KD4-iD iJ&''n 3#9 &^& T$)c 3#9: T$)c 3#9:
o ,#1u 4#)( 4#)( (in #,#1u 4#)( 4#)( (in # ii co) 3$%*ng (inco) 3$%*ng (in I#I#iiJJ
^3og4#^3og4#iio ,#1u (u (u (in -,#1u (u (u (in - ii co) 3$%*ng (inco) 3$%*ng (in I-I-iiJ ^3og4-J ^3og4-ii
o T= T= I#I#ii J I- J I-ii
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L$%*ng (in ($%ng o>L$%*ng (in ($%ng o>
]86n (uB81n 3B)($%"ng
a1 b1
P(b1/a1)=1
a2 b2
P(b2/a2)=1
a3 b3P(b3/a3)=1
an
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L$%*ng (in ($%ng o>L$%*ng (in ($%ng o>
Tong ($*c (8.D c#)c 786n (uB81n Tong ($*c (8.D c#)c 786n (uB81n($%9ng FuB86n co) ni8>uD 3#9; co($%9ng FuB86n co) ni8>uD 3#9; co
F#)c u#.( (u /$%*c c#)c (inF#)c u#.( (u /$%*c c#)c (in --ii 7i7i4#)( (in4#)( (in ##ii gi#"; Fuo.ng'gi#"; Fuo.ng' a#1n co9n 3#*i 8 3#9 F#)c u#.( (ua#1n co9n 3#*i 8 3#9 F#)c u#.( (u
/$%*c c#)c (in/$%*c c#)c (in --77DD 77≠ i≠ i #9#9 7J&''n7J&''n''
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L$%*ng (in ($%ng o>L$%*ng (in ($%ng o>
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a1 b1
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o HAHA r Xr X
o HA J X 7iHA J X 7i A co) ;oä( 7B) i8äu c#OcA co) ;oä( 7B) i8äu c#Occ#On Fu#.( i8än #9 c#)c 7B) i8äu co9nc#On Fu#.( i8än #9 c#)c 7B) i8äu co9n3#*i c#Oc c#On 7o6ng Fu#.( i8än'3#*i c#Oc c#On 7o6ng Fu#.( i8än'
o HA J HAHA J HA;#F;#F 7i c#)c 7B) i8äu cu"#7i c#)c 7B) i8äu cu"#
nguo1n 3#9 /#ng F#)c u#.('nguo1n 3#9 /#ng F#)c u#.('
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,oä -#.( /0n /o1ng,oä -#.( /0n /o1ng
(%9i(%9i ,oä -#.( /0n /o1ng (%9i 3#9 /oä -#.(,oä -#.( /0n /o1ng (%9i 3#9 /oä -#.(
/0n (ung -=n cu"# ;oä( c#4 #/0n (ung -=n cu"# ;oä( c#4 # iiD-D- ` `
-#.( 7B9 (ong 48)4 -i8.n /o@i ($9-#.( 7B9 (ong 48)4 -i8.n /o@i ($9ngu%9n A #ng nguo1n ngu%9n A #ng nguo1n '' ]B) i8äu:]B) i8äu: HAHA V#äB:V#äB:
∑ ∑= == n
i
m
ji
ji ji
a p
ba pba p AB H 1 1 )(
)/(log)..()(
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,oä -#.( /0n co) /i81u,oä -#.( /0n co) /i81u
7i8än7i8än ,oä -#.( /0n co) /i81u 7i8än 3#9 /oä,oä -#.( /0n co) /i81u 7i8än 3#9 /oä
-#.( /0n (ung -=n cu"# ;oä( 7B)-#.( /0n (ung -=n cu"# ;oä( 7B)
i8äu #i8äu #ii (uoäc (#ä4 A 7i /# -i8.((uoäc (#ä4 A 7i /# -i8.(;oä( 7B) i8äu -#.( 7B9 -;oä( 7B) i8äu -#.( 7B9 - ` ` (uoäc (#ä4(uoäc (#ä4''
]B) i8äu:]B) i8äu: HAfHAf V#äB:V#äB:
∑ ∑= =−=
n
i
m
j ji ji ba pba p B A H 1 1
)/(log).,()/(
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To.c /oä 3#ä4 (in To.c /oä 3#ä4 (in
,8@ /#)n gi#) ;$)c /oä n#n c#ä;,8@ /#)n gi#) ;$)c /oä n#n c#ä;cu"# <u#) (=n 4#)( (in ($9 ;oä(cu"# <u#) (=n 4#)( (in ($9 ;oä(
nguo1n (inD (# $" du*ng 7#)i ni8ä;nguo1n (inD (# $" du*ng 7#)i ni8ä;(o.c /oä 3#ä4 (in cu"# nguo1n (in'(o.c /oä 3#ä4 (in cu"# nguo1n (in' ,0n ngh#:,0n ngh#: 2o$c %oä laä0 tin cu!a2o$c %oä laä0 tin cu!a
moät nguoàn tin laø löôïng tin maømoät nguoàn tin laø löôïng tin maø
nguoàn tin %où 0haùt ra trong moät %ônnguoàn tin %où 0haùt ra trong moät %ônv thôøi gian1v thôøi gian1
]B) i8äu:]B) i8äu: RARA
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To.c /oä 3#ä4 (in To.c /oä 3#ä4 (in
C#)c (!n:C#)c (!n:
RA J nRA J nXX ' HA J n' HA J nXX ' IA' IA
T$) nguB86n: -i(fp T$) nguB86n: -i(fp Tong /o): Tong /o):
o nnXX 3#9 o. 7B) i8äu do nguo1n 4#)( #3#9 o. 7B) i8äu do nguo1n 4#)( #(ong ;oä( /%n 0 (%9i gi#n'(ong ;oä( /%n 0 (%9i gi#n'
o HA 3#9 /oä -#.( /0n cu"# nguo1n (in'HA 3#9 /oä -#.( /0n cu"# nguo1n (in'o IA 3#9 3$%*ng (in (ung -=n cu"# nguo1nIA 3#9 3$%*ng (in (ung -=n cu"# nguo1n
(in'(in'
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To.c /oä 3#ä4 (in To.c /oä 3#ä4 (in
V! du &V! du & * * : Gi#" $" co) nguo1n (in KbXD&: Gi#" $" co) nguo1n (in KbXD&/#ng F#)c u#.(' Nguo1n (in n#9B 4#)( #/#ng F#)c u#.(' Nguo1n (in n#9B 4#)( #'XXX 7B) i8äu (ong ;oä( gi#6B' T=; (o.c'XXX 7B) i8äu (ong ;oä( gi#6B' T=; (o.c
/oä 3#ä4 (in cu"# nguo1nm/oä 3#ä4 (in cu"# nguo1nmGi#"iGi#"i
L$%*ng (in (ung -=n cu"# nguo1n:L$%*ng (in (ung -=n cu"# nguo1n:
HA J 4bX'IbX q 4b&'Ib&HA J 4bX'IbX q 4b&'Ib&
J k'& q k'& JJ k'& q k'& J & -i(f7B) i8äup& -i(f7B) i8äup nnXX J 'XXX 7B) i8äu f J 'XXX 7B) i8äu f &aä# 456 8 n&aä# 456 8 n99 x :56 8 ;<1999 bit=( 8 ;< x :56 8 ;<1999 bit=( 8 ;<
>bit=(>bit=(
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To.c /oä 3#ä4 (in To.c /oä 3#ä4 (in
V! du 2V! du 2 * * : Gi#" $" co) nguo1n (in K#&D#2D #+D: Gi#" $" co) nguo1n (in K#&D#2D #+D# /#ng F#)c u#.(' Nguo1n (in n#9B 4#)(# /#ng F#)c u#.(' Nguo1n (in n#9B 4#)(# &'XXX 7B) i8äu (ong ;oä( gi#6B' T=; (o.c# &'XXX 7B) i8äu (ong ;oä( gi#6B' T=; (o.c
/oä 3#ä4 (in cu"# nguo1nm/oä 3#ä4 (in cu"# nguo1nmGi#"iGi#"i
L$%*ng (in (ung -=n cu"# nguo1n:L$%*ng (in (ung -=n cu"# nguo1n:
HA JHA J -i(f7B) i8äup-i(f7B) i8äup nnXX J 7B) i8äu f J 7B) i8äu f &aä# 456 8 n&aä# 456 8 n99 x :56 8 bit=( x :56 8 bit=(
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To.c /oä 3#ä4 (in To.c /oä 3#ä4 (in
V! du* +V! du* +: ?oä( nguo1n (in go1; co): ?oä( nguo1n (in go1; co)c#)c 7B) i8äu (in 3#9 K#&D#2D #+D #Dc#)c 7B) i8äu (in 3#9 K#&D#2D #+D #D
#5D#D # co) F#)c u#.( n$ #u:#5D#D # co) F#)c u#.( n$ #u:o a#& J &fl a#2 J&fjl a#+J&fjla#& J &fl a#2 J&fjl a#+J&fjla#J&fja#J&fj
a#5 J &f&l a# J&f&l a#J&fa#5 J &f&l a# J&f&l a#J&f
o Nguo1n n#9B 4#)( # 5XXX 7B) i8äu (ongNguo1n n#9B 4#)( # 5XXX 7B) i8äu (ong;oä( gi#6B' T=; (o.c /oä 3#ä4 (in cu"#;oä( gi#6B' T=; (o.c /oä 3#ä4 (in cu"#nguo1nmnguo1nm
7/17/2019 Chuong 2- Tin & Luong Tin
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To.c /oä 3#ä4 (in To.c /oä 3#ä4 (in
V! du* V! du* : T!n (o.c /oä 3#ä4 (in cu"#: T!n (o.c /oä 3#ä4 (in cu"#;oä( nguo1n (in 3#9 ;oä( -oä -i8.n;oä( nguo1n (in 3#9 ;oä( -oä -i8.n
/o@i Af (!n i8äu (o#*i %)i (#1n o./o@i Af (!n i8äu (o#*i %)i (#1n o.3#.B ;#>u 3#9 j ]W #9 3$%*ng ($"3#.B ;#>u 3#9 j ]W #9 3$%*ng ($"o#) 25 ;$)c'o#) 25 ;$)c'
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To.c /oä 3#ä4 (in To.c /oä 3#ä4 (in
V! du* V! du* : T!n (o.c /oä 3#ä4 (in cu"# ;oä(: T!n (o.c /oä 3#ä4 (in cu"# ;oä(nguo1n (in 3#9 ;oä( -oä -i8.n /o@i Af (!nnguo1n (in 3#9 ;oä( -oä -i8.n /o@i Af (!ni8äu (o#*i %)i (#1n o. 3#.B ;#>u 3#9 ji8äu (o#*i %)i (#1n o. 3#.B ;#>u 3#9 j]W #9 3$%*ng ($" o#) 25 ;$)c']W #9 3$%*ng ($" o#) 25 ;$)c'
Gi#"iGi#"i T#1n o. 3#.B ;#>u J j ]W ^_ T#1n o. 3#.B ;#>u J j ]W ^_ nnXX J jXXX 7B)J jXXX 7B)
i8äufi8äuf L$%*ng ($" o#) 25 ;$)cL$%*ng ($" o#) 25 ;$)c
^_ IA J 3og^_ IA J 3og22 &f&f25J 3og&f&f25J 3og22 22jj JJ j -i(f7B) i8äuj -i(f7B) i8äu V#äB:V#äB: RA J jXXX F j J 'XXX -i(f J ]-i(fRA J jXXX F j J 'XXX -i(f J ]-i(f
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To6ng 3$%*ng 786n To6ng 3$%*ng 786n
,0n ngh#:,0n ngh#: 2ho)ng löôïng "e)nh laø löôïng2ho)ng löôïng "e)nh laø löôïngtin to$i %a coù the?tin to$i %a coù the? /i <u# 786n/i <u# 786n trong moättrong moät%ôn v thôøi gian maø "ho)ng coù loãi1%ôn v thôøi gian maø "ho)ng coù loãi1
]B) i8äu:]B) i8äu: CC -i(fp-i(fp ?o>i 3o#*i ;o6i ($%9ng (uB81n d#>n 7#)c?o>i 3o#*i ;o6i ($%9ng (uB81n d#>n 7#)c
n#u 8 co) (o6ng 3$%*ng 786n 7#)cn#u 8 co) (o6ng 3$%*ng 786n 7#)cn#un#u
No)i cungD (o6ng 3$%*ng 786n ($%9ng 3#9No)i cungD (o6ng 3$%*ng 786n ($%9ng 3#9#.( 3%)n o %)i (o.c /oä 3#ä4 (in cu"##.( 3%)n o %)i (o.c /oä 3#ä4 (in cu"#nguo1n'nguo1n'
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To6ng 3$%*ng 786n To6ng 3$%*ng 786n
,8@ $" du*ng co) i8äu <u#" 786n (uB81nD,8@ $" du*ng co) i8äu <u#" 786n (uB81nD(# c#1n (#[ng (o.c /oä 3#ä4 (in cu"# nguo1n'(# c#1n (#[ng (o.c /oä 3#ä4 (in cu"# nguo1n'
T$%9ng co) 2 c#)c: T$%9ng co) 2 c#)c:
o T#[ng n T#[ng nXX: 7B (u#ä( g8)4 786n (8o (%9i gi#nD: 7B (u#ä( g8)4 786n (8o (%9i gi#nD$" du*ng ;# 4#)( i8än 3o>iD ;# $"# #i ;#$" du*ng ;# 4#)( i8än 3o>iD ;# $"# #i ;#co.ng ni8>u'co.ng ni8>u'
o T#[ng HA: c#)c 7B (u#ä( /i81u c8. o. T#[ng HA: c#)c 7B (u#ä( /i81u c8. o.
C _ RAR(A)
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V! ds: T!n 3tng (inV! ds: T!n 3tng (in
V! du* : a8)4 -i8.n /o@i Af (!n i8äuV! du* : a8)4 -i8.n /o@i Af (!n i8äu(o#*i: (vn w 3xB ;yu: z J j7WD 3$%*ng ($"(o#*i: (vn w 3xB ;yu: z J j7WD 3$%*ng ($"o)# 25 ;$)c' T!n (o.c /oä 3#ä4 (in cu"#o)# 25 ;$)c' T!n (o.c /oä 3#ä4 (in cu"#-oä -i8.n /o@i Af'-oä -i8.n /o@i Af'
Gi#"iGi#"i::o RA J nRA J nXX F HAF HA &&
o nnXX J z J jXXX ;#>u f J z J jXXX ;#>u f o Nguo1n /#ng F#)c u#.( n86n HA J IA JNguo1n /#ng F#)c u#.( n86n HA J IA JI#I#ii J 3og J 3og22&f4#ip J 3og&f4#ip J 3og2225p J 3og25p J 3og2222jjp J j -i(p J j -i(f;#>uf;#>u
o RA J nRA J nXX F HA J jXXX F j J XXX -i(f'F HA J jXXX F j J XXX -i(f'
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To#*i To#*i
N0 = Fs = 8000
H(A) = I(A) = 8
A/
To*#i
eo.
jXXXFj
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Voic8 ^ (88oVoic8 ^ (88o
N0 = Fs = 32 !"#
H(A) = I(A) = 12
A/
L eo.
+2{&X|+ { &2{2R
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