trờng đại học hàng hải việt nam
khoa điện - điện tử tàu biển
bộ môn điện tử viễn thông
luận văn tốt nghiệp
Tên đề tài :
Cấu trúc và nguyên lý hoạt động của tổng đài starex - vk lg
!
Môc lôc
Trang
"#$%&
Ch¬ng 1 : C¬ së lý thuyÕt
'()&*+,$-
''./-0123-
45&6/-07.
44 0)&0+/-08&
49 ./-07.
4 70!:0/-0,30!
4; ./-0$"<&=+
935&623>.
94&!&35&6>.
99:02>.
9:$3,!?*:02>.
9;!@&<A!B!@!?*,23,
9C(!D!2>.!EF,G;H
'''7&=I!,
4 0)&0,!&=I!
9 70!:D!!&=I!,
94 7&=I!3J*
99 7&=I!"*
994 +&3I!&=I!$%&1-
999 +&3I!&=I!$%&<*
70!!@&<A!!?*3,!&=I!,
; 7&=I!,KK
;4 7@&<A!<"!&=I!KK
;9 -&=L,)&*<"!&=I!
'&+!&=I!E1MN&=LOL1!0!!&P!Q
4 7&=I!E
9 &+MN&=LOL1
Ch¬ng 2 : HÖ thèng tæng ®µi STAREX - VK
'&()&*+,($1RSTUK
4 &!&
9 70!3V 1$W!8!?*,
70!X!Y$W!H!-&H*-
; 70!J,$W!<!?*,
''7@&<A!,($1RSTUK
'''B$+&3I
4 7D! B$+&3I
9 7@&ZB$+&3I
94 O[MN\7
99 O[MN'7
9 ']\-<
9; ,$+&3ILHXHV-^<&B_7.>7`
'B!&=I!_`
4 7D! B!&=I!
9 7@&ZB1!D! !0!3,
94 O[MN!8
99 ,*-L&H*-:a_R'b`
9 *-L<&3L,_>7'b`
9; ,*-L!0!X!YP_'b`
9C ,-!0!HVJH0-_.b`
9G ,!&=I!"*_b`
B3L,_'`
4 7D! B'
9 7@&ZB'
94 O[MN'
99 O[MNc
9 ,!&=I!3J*_b`
9; ,$HP_cTb`
9C ,3L,dM&<&B_7>b`
'B
4 V -$P!?*B
9 *-Ld*\1
''7D! '>c!?*($1RSTUK
4 *-L!(!:HV9ef>
9 *-L!(:!@gef>
'''7@&<A!%+!?*($1RSTUK
4 ()&*
9 $+&1
Ch¬ng 3: HÖ thèng cíc vµ xö lý cuéc gäi
I.7!!-!&P!Q
4 ()&*
9 70!:08!!
70!?Y!O[MNdM&!!
''U[MN!&P!Q
LM&6
Lêi më ®Çu
7hO&0<I3Ji!?*jJLi!J
:a_**M-`*!J,_*M`kjJc*$/1
$*!EdHL$($IP6O&0<I!?*"$eK
!0<IM@1$%&<-)&0<Z0<IM1a0<I$
-<P3l<-1M/(70!($1,<*$"!&!@P:
d&8!!-$1-iO*1PM-!0!X!Y30!
$+1m7@&<A!1&=MN-$P!?*($1,RSTUK
mn-&,$*<*P!0!Z()&*+($1,E!&
1,($1RSTUKE<
+1H*-%
PhÇn 1&P!0!()&0@!?*,$-E!&o
!0!35&6!:HV<-!O[MN8&LEk)&0<Z$+&3I
!&=I!H*-!&=I!!-!0!3-_!&=I!3`k
1!&=I!!-!0!M&dM&_!&=I!E`o)&0<Z<&=+
!0!8&$/$p!O[MN1=<$"<&=+$I($1!&,
PhÇn 2B&!D&ZI&!@&<A!,($1RSTUKk
!0!3,!D! 1!3L,!0!3,$E"!0!*-!:HV%
1=!&!D! '>c!?*,k!0!*-L!?*!0!&
H*-1=,
PhÇn 3U2)&0<ZO[MNP!&P!Qk!0!8&-18&H0-
&i&H*-$L($1
&=k-<Z$P3LD!1"*!F!LP&
M&6 !F+&L&Eq&*M&6 1=kn<@-$p!aENkH(
&!?*!0!%=0-1!0!H$In!EII&B&l!+@$+1=:
TO!B1!V:aA$^!?*!0!%=0-<-3-*k$W!
HM1%=0- !$/6Z!rHV-kA$^n-1
1M&6 1=
Ch¬ng 1: C¬ së lý thuyÕt
I/Tæng quan vÒ hÖ thèng ®iÖn tho¹i
.P,$-H*-PM-!0!3,O[MN8&-
s-M6&=L,$I<&=+JLEi&H*-!?Q&
H*-HXQ
Z44 JV!0!)&0<ZO[MN8&<-,
70!&H*-$p!,$L($1Hs$"B=&H*-_[Y!0!
$J!0`.P3<&=+!-$p!Hl$%&LM63!E8&-
<&=+<$Eq&0<ZO[MN8&*&!0!8&i0=$-
!?*&H*-!?Q_!V8&LE18&H0-&`$p!<&=+
($1k<!E)&*HPHL$(R]>_L&M1!0!&H*-:a`o*&
$E!0!8&1=!h!0!8&,_i!0!&H*-,`$p!$*1-
23n-&!&t1,$*0Y_,7.9;
321,7.g32`70!321=*&$E$1-
3,!&=I!,o3L)&V!?*)&0<Z!&=I!M1-<*$p!&=L
,d**&H*-"LM6!0!3-*!+&cL&*&
H*-s<-*($1!Y!HP30!*&ZD!!&=I!!*-:$p!
a!k$EM1!&=I!!&=IL$p!a!H#($1!&=I
L_-MM`
cL&!0!($1$p!,*&Hsd$"B=Z3V
,Jd*!0!&=L&H*-H@3ZM1!EIk,MpB=
, M<@+&i$EkO&@($1p,M1Y$@&,
!0!($13&a!#<P*-L!?*!0!&H*-
($1!&=I!)&,!L!<*$"Y!Y!-!3L,&=L
!0!!&P!Q)&,!L$Ek!0!($1!?*u)&,!*V$p!,
($11=70!$"!0O&=$:1!0!$"H*,,!$P!*-
$p!!&!@H#!0!Z1!0!$"<&=+)&,!L!:
HVk1!0!!%&H*$p!h<-!0!!B&MY!
./-0
_R]>`
2
3
V/
_R]>`
7&=I
!
&H*-
&H*-
v"B=&H*-
0!
3
H×nh 1.1. S¬ ®å khèi hÖ thèng ®iÖn tho¹i
!&=I!
!&=IL
($1!Y!HP
ở8*&k($1&wa!!0!)&0<Zp!M8*0$I
$*8&LE&H*-!?Q$P!8O0!!*-@
II/ Mã hoá và ghép kênh
1. Kỹ thuật mã hoá PCM
1.1Khái quát về mã hoá tín hiệu :
<-!0!,JE!&k!0!8&x&=&yz
LEkZV &,<&=+$ p!$O*!%VHL$(1P
&8&,q&0<ZHL$(1=$p!QM1/-0&*<F!?*
/-0&M1$W!H)&*<QkE%B!*-!@MpM&MQ!1
!-2B!*-&)&V[Y(%!?*,<&=+
&6-0/-0&!EIOnO2J)&*&HI&!?*E
M1/-08&LE_HL$(8&-:a18&,
XB`
*=k:0JY@$I,-0LEM1$+&!Ln-
/7.
1.2 Mã hoá PCM
7.$p!H#)&0<ZM@=&kMp[1/-0
f:$3,!?*HP/-01V/<-,7.
*$-$%&!?*7.M1M@=&Hs!0!8&B*6k
E-<*P&%a!0!&**M-!&tR._&Mn*M&n
-&M*-`70!&7.!EVH$P,L*&<-VM1!e!
Ln-M1B!*VH$P1=1P,!0!3-V@!V
!0!&!0!D!H$P1-$EL&&1-<:1-P3-V$W!H
1-$EZ$p!0!hD!0<X!?*3-V$Eo!J!1=$p!QM1xMK
p[-0z7&,!h<-HP/-0k$PM!?*!0!&$/$p!Mp[-0
$p!HI&H#!0!/XBc6=k)&0<Z7.-<*P!&u!0!
Hình 1.2. Quá trình mã hoá và giải mã của hệ thống PCM
O&$+&HMvp[
@=
&
vp
[-0
./
-0
0-
i/
ePV
/
eP
MQ!
U&R. J
eL$(R]> eL$(>]R
!d,XBk$p!EM1!0!mi7.z$!-E8
&6
>FHXB1=!EI$p!!&=I<-P($1,-W!
!EI*)&*PM3L<&=+,*&3$/!&=I*8!
p$"<&=+$E_!&=I$(i/XB*/$"<&=+`
$%&&k/XB$p!!&=Ip!<#M1P/=,L
!0!/7.H#HPV/1!0!&7.$p!$*HPMQ!J@$I
M@=<*$p!8&E&#{6
1.2.1 LÊy mÉu :
@=&!8M1)&0<Z<"<!-08&:aB=M1H!!&=I
8&*JMY!18&*J#<:Z
<!Hs:0M@=&_*M`o*-!-8&<"<!V*
$%=$?J!?*8&:a$I!EI0-$p!JP!0!
<&a!#$%&&
8&<"<!M1P/=O&*D!k"*Q!0!O&1=M1
!0!O&R.
q&0<ZM@=&$p!a*<$XMNc=)&XMN1=0HI&
*&x.P8&U_`!E(d&i_g÷|
*O
`}$p!-1-1O0!$X
H#d0<XU_3∆`!?*EM@=#!0!3-V"*≈|
*O
o|
*O
M1%,!*-@!?*(1U_`x
cL&*Q
M
M1!&3~M@=&1|
M
M1%,M@=&k*!E
U_`
U&R.
8&B*<$-%&L!E( Mp6<&
<-Vigg}$L;gg}a!L(LE!?*!-"3Ii%
max.2
1
F
Tlm ≤
H×nh 1.3. S¬ ®å minh ho¹ ®Þnh lý Nyquit
M
,@_1< }`!-$L%,!*-_1Z}`Z6=k$I3JB=
<*d2-Y!V)&0M<-)&0<ZJ-Z!!lH•!0!
1%%,-1VE<M1!%L!1=$p!a!"
!MQ!J@o3$EwM-H•!0!1%%,M:;gg}
c<a!Lk*,-MQ!H !EIOV=<*-!0!!$W!8
3J,!%,!l$p!!Q"<@0;ggg}16=%,
!a!$!?*8&-$p!!QHs;}
*8$p!%,M@=&M1
77'$/3&=LX!-,!&t7B&€&[Y&/-0
H8k*!E,!$PH!?*3-,&!&tM1
-,
•H×}•G;H]
ë$%&&k$I3JY!$p!8&H*$%&"*hHPMQ!J
@8&<"<!n-$XMNc=)&3)&*HPMQ!J@%,
!:HV!?*8&w!-<*8&MY!H*$%&
q&0<ZY!$E$p!-#Z*&
U‚_`U_`
<"<!-08&k=&!%&O&R.!E"*<0•K
a!L:$,M_!EP0<X1-$E`E=&!%&|
M
VM:
9|
*O
cL&3J-//$+&1=p!(wOV=<*ƒ*M1(
8&&$p!HXHL-(,!
s
KHzF
Tlm
µ
125
)(8
1
max.2
1
===
U
„
_` U
_`
H×nh 1.4. : S¬ ®å biÓu diÔn minh ho¹ sù phôc håi tÝn hiÖu liªn tôc
>-,!$PM@=&M1<@*!0!!$a!)&0<ZM@=
&"M1M@=&1&=<Zo<-$EP<*}-<-$P*k
$E*<FP3-0l#n-a$+&3I!?*O&M@=&.D!8
&$/M@=&$p!8!M<PY$1$*$LHP3&=L!$$!E
<#30!*-<!MA!LY!O[MN[Y<#30!*-$I i*a
E$i!0!F<F<-3-V"*d*!0!O&M@=&
1.2.2Lîng tö ho¸
(8&,!
(8&*&
M@=&
(8&!Ea
!(
(8&0!3!Ea
!(
H×nh 1.5.: Sù chång phæ
c&8
&1-
8&R.
-
O&
H×nh 1.6. S¬ ®å biÓu diÔn m¹ch lÊy mÉu
1*=LP8&:a$/$p!M@=&Hs6d&!?*!0!
D!H$PkD!M1HL$(8&MY!n-D!18&H$P<"
<!…&$I!?*Mp[-08&$/M@=&M1V$p!V#!?*
B70!D!8&<"<!QM1D!Mp[-0k3-V!0!d**D!
Mp[-0QM1H!Mp[_∆U`
c"*a!Mp[-0O&R.Hs!0!!$W!H<-
!0!!1="*-00<X!?*O&R.!0!D!!&t!-<!k
:D!0!D!Mp[-0$I)&=L$X*1-D!1=*=D!3*
7 !D1-H!Mp[-0∆Ok"*BHMp[-0&=L81Mp
[-0&=L*,d*D!Mp[1O&R.QM1BMp[
p[-01∆U•!-QM1Mp[-0&=L8k"!rh
3!EaHL$(+D!3JM7F$,8&!E*=$(D!Mk
L&0YMp[-0&=L8Zw!Ey,8&<BMp[
M_]c`.&,VBMp[Z*VVH!Mp[k3$E,
D!Mp[ M&=k! )&0,D!Mp[w$L
- ,H8h$I/!0!D!Mp[ M1 ,!$PH1-6=
(!L!?*8&,
- !hPV$P8&k! )&0,D!Mp[w$L
D!Mp[#$%&&HX6%0!$PB<-!0!!
$[
.W30!L&!0!H!Mp[M@=&Hs*&+3-V!0!Z2-
Mp[wO@&:$,!0!8&!EH$P•:H$P!0!8&
30!Z2-HX0H#"n,j&y,d*8&
<*1 Mp+&O@&:3D!8&6HXVO&, p
[-0&=L
:01=$*<*s3l!Y!d!L!?*:0<
Hs0YMp[-03J$+&!*!0!D!Mp[n-1M-*<k
ƒ*M13-V!0!d*!0!D!Mp[$p!!QM$,!0!D!8
&M!F!0!D!8&•Z3-V!0!d*!0!D!Mp[
!Q•c"*!D$p!<s:0Mp[-0&=Ln-
M&6M-*<wM1!-y,]c3JY&P!1-D!8&1-<
a!L[Y(HL*)&=M&6Mp[M&6R1M&6µo#$B=*w
3J$*&!D&*)&=M&6$Ep[-0&=L8M1!:#$I/
-0&=L8k!FMp[-0&=LM1!:#$I/-0&=L
1.2.3 M· ho¸
*&3Mp[-0O&R.kuO&R.w$p!HI&jH#P
EH8XBQM1Pi/77'$/3&=LX!-,!&t
7B&€&[YH8!-Pi/k6=w!E9CGi/:Dq&=!
H8$%&M1H@&1†H8,M&L*&$E
7@&<A!i/$p!I*&
I/-08&"*h!0!:0*&
*,/-0&=L8
LML!0!D!/-0∆Uo3/-0H8Z$L,$*M1
c•9
K4
O&
:01="*HL$(MLHXQ‡k$:V
K:0!B'n<*M./-0H:D&-0ku&K
:DP<QMpH8
K:0/-0<a!L<-:01=k/-0<a!L*=
M1:0--o/-0H8-<*9
K4&ku&*30!4∆U
-&!E3$EV!E9
K4HP-0
:01=<@*)&0D!k3J3Lk*,:
$,M
H./-0&=L
./-0&=L[Y35&62K/*O2!0!M-*&
-4R*M-7-*-<_c28&:a`
-9>*M7-*-<
1.3 C¸c kü thuËt m· ho¸ sè kh¸c :
.W!h!0!35&6/-07.G;H1hM&6R-W!
M&6µkM1!0!:0$p!!&t-0)&,!L!-!0!($135&6,k
!EP1:0/-030!$p!h<-!0!DY$W!
H70!:01=a!/-0LE,!$P•:,!$P
G;3H!?*7.k"$E$p!6Y$p!!0!3V !?*,<&=+
Hg H4 H9 H H; HC HG H†
70!H,M&
e@&
H×nh 1.7. CÊu tróc tõ m·
R*M-
c2v
:a
./
-0
V
/
/v
:a
./
-0
V
/
c2
,
/
,
R*M- R*M-
R*M-
,(%!L3<&=+&=k!0!:0/-0,!$P
@1=wHX!L+!@Mp$W!HM1j&12-%,
K7>_7-&-&M=*<*HMnM-n>nM*-&M*-`5&61=M1P
O&@!?*$+&!L>nM*k<-$EPH8$:$p!h$I/-0u&
R.-W!M:-W!•:&<!$EZ3JHXH#Pi
/Hk/-0!EI-$P!0!,!$P30!*&1-3-V9g
H7>$p!h<P</<-!0!,!L+!@MpJ
j1<I3*1!l!!lc-1<*!F$p!h<-!M&
dLE$/$p!,-0$VHV-aL3!?*HP
KR>7._R*n>ˆˆn<n*M7.`‰+&!L/O&*a8!
5&61=M1PO&@!?*7.!&to#$Ea30!Hd*!0!&
ML*&$p!/-0*=Z!0!&$p!/-01$p!<&=+<$"
B=77'!E$+XP!&tR>7.9H1!-/-0LE
1.4 M· ho¸ ®êng truyÒn
*&)&0<Z!&=I!dM&!-!&P!Q#(p/X
B$p!HI&jH#!0!&7.8&1=3J3J8!p!-
!<&=+<$"B=k$W!HM13!%!&=I$3-V!0!O*-
@V*@$+*&
_` I$X"$p!&=<*$%&&!?*,1H@3Z"$I1-
*=*&$E8Y$p!0kFH$p!<&=+V!EP%,!*-
!&=Ii4*g1ig*4&=k/XB-<*iP
,7.kJ"!EPV<P!0!&!E!hH8kH*-!&u
!0!H41*=!VP!&u!0!HgML*&
_` !<&=+!0!8&7.XBk$p!-1iD!$0g1
:-P8&$"B=*P Mp$03I MpP
!+&_>7`1V%@k!0!HL0<,<&=+3J3I-0
(!0!1% Mp1="!M)&*$La<&=+(
Mp%0!?*!0!8&XB1=M1j&8&B*
<!0!p!03+*&
>-$EkPa!&=I$(*/$"B=hp$"<&=+
M1$+&!%L$I3l!Y!@$+$HP1(%@7E+&/$K
"B=$p!$+O&@kEu<p!0!D!$P[YH J30!*&ka
a!1[Y!0!LHXD!
U2P,M-/$"B=JY*&
*./R>']R.'
./$"B=M1(p*35&6$W!H
R>'KRMn<*nK>K'n<-QM1$V-p!M&B!0!H$I!Š
1-P&$X"!%L
R.'KRMn<*nK.*<3K'n<-QM1$V-M&BH4$IM-H•
1%%@<-8&XB
- R>'<-L<Z1=!0!!d,M&B$p!$V-_H41Hgo
Hg1H4`+&1=!&!@Pa* (I,!&=I$(gK4
14Kg-8&XB,!
KR.'5&6R.'!&=I8&XBR>'!r0<Xf41g
*/M^!a!H*0<Xf4kgk1K4+&1=$$p!Hs!0!*=$(
M&B!0!H80<X4<-8&XB6*K4<-8&<*
_&6dm*<3m$p!h$I!rH4`&&@!?*a!&=I$(/1=
$p!O0!$XH#rMJa!a$p!!&=I-3V !?*/$K
"B=>-$EkR.'!E&&@/M1G†‹Z!rP8&*D!$p!
&=<*iH*<0!?*8&/$"B=DH*
Œ_4×9`_4×`•×4gg‹•G†‹
H./>e
./$"B=>eh/R.'$I-<*P8&M^!a!H*D!
!E<@81%%,@5&6/-01=M-H•!0!!&ug1
Hs!0!*=H4V$X1-X<8!?*uHgD$I$VHV-,Mp
,$*!*!HgML*&M1.uH4V$X$p!O0!$XHsP
*-0!$V-!a!!^HD!k"$E8&XB&!EI$p!0L#
$%&O*V-!a!!^HD!$p!a!Hs!0!l*&%a$V-!a!
M&Bf4kK4kf4$!-HXB4_$EM1{<*!?*R.'`kH4
V$X$p!O0!$XHs!0!MWM!a!8!?*H4<!E>-$Ek<-
P&%aXB4gggg4Z/$"B=H*-fgggfK
!./;e_;H*<=-n<*<=`
./1=-<*P8&M^!a!Hs!0!$(!0!3,;HXB
1!0!3,HH*<0L<Z1=!EP,!0!&$Is
!"M-H•1%%@k$EM1
- ./-0$p!L3L$I$VHV-u3,H!@H*!D*8@PH
4k-$E-<*J$X"!%L
- p!$1=!E&&@Ž‹Z;HJ_; ×9<0`!D*
<-P8&HH*<0
_;×9`_×`•Ž‹
K,!$P$"<&=+!rHs];,!$PXB7.!V,!$P
1=!-2!0!*,!?*,<&=+_$Pjj&k3J*0
`$p!!V
./Ge;_GH*<=-;n<*<=`
p!-<*Hs!0!!&=I!0!3,GHXB*!0!3,;HH*
<0P!0!<a!LkGe;$$p!&&@
_G×9`_;×`•4gg‹
!hV4],!$P<&=+-8&7.XBcP&J
$X"$p!$VHV-H#a!?*Pm*<3m<-u3,H*
<0&=k!r&+3L$,M-/1=!F!E+&
!L
2.Kỹ thuật ghép kênh tdm
2.1 Giới thiệu chung kỹ thuật TDM (Time - Division - Multiplex)
q&0<Z6!&=IP,8&$")&*P:<&=+
QM123LHX!EYM3L!0!M&H8,M&M1HP
23
<-!0!($1,kLHX$%&!&,!?*,23*!+&
H*-PHP23Y!Y!-<&=+1PHPBV3
Y!Y!-&
7E+&35&623ku35&63*0!3V !?*P
,$I-<*10P*,$6!H-1-1!8O0!2
3$p!a!iaB,V*,!r$X1-u3
<-35&623n-"*_>.`Z*,"*$p!
$*<*M1&!&t!-!270!F,!E!h,!$PH8*&K
w!L#3n"*@$X1$p!MWMn-!&3~k!E%,Hs
%,M@=&!?*8&3<&=+
>F,@@!?*3,!E,!$PG;H:D,!$P!?*
3-,&!&t*HL<sk8&-!EV%,ig}
$L;}k$p!M@=&#%,}:D!&3~M@=&M149Cà
1$p!/-0H8!E,!$PG;H,!$P1=$p!M@=M1!&t@
@!-!23,
n-&!&t!&<Lk!2P,Mp!0!3-
!&t1-P3!E,!$PH8M:$p!a!Hs!!-"
*!?*u31lOL!A1-d3n"*$/X<!!
2!0!3-!E,!$PM:!a!:a6=
2.2 Phơng pháp ghép TDM:
<-35&62>."*[Y(HL*:02
3M12i12H8
K,2i.uP(p/_Pi/`!?*P3wM%Mp
!LP3n"*<H
- ,2H870!H8!?*u3w$p!<&=+$<-F,,!$P
!*-P!0!<M
eP
2
3
eP
B
V
3
4
9
4
9
8&$vp!2
Hình 1.8. Sơ đồ khối biểu diễn kỹ thuật ghép kênh
*@=k2iD!:H#E=&!%&[YPHP$$I
Md8&$%&1-B6!61d8&1=w$p!M@=
&hp,!$P!?*3<&=+&=k2H8wB=D!
:33JY!M8&#$%&&k-!0!H8!?*3$p!<&=+$<
<w
c-1<*k!FP,:030!$p![Y<-Jk
*O2P:0$IZM12,3
,!$P<&=+<-,M1Cg.Ho 6=!&3~49Cà!EI
!D*$p!G9CgH8-W!g3-V3H8<-u3&=k
u!&3~$p!B1P3-V!-M11!&3~!-ku!&3~
!-$p!h!-P1<W$@70!!&3Z!-!E&Mp!,$Xk
!EI-1<-u<W$@-W!&Mp!?*!&3Z!-!EI
*=$(P!0!:Dhp=&!%&!?*<W$@.u<
W$@<&=+JEO&J&=LkE6-1-1!0!!&
3Z!-!?*70!H8J<-uE!0!H8Hl$%&!D*
J$HPE*k$HPn-H8k$HPn-!&3Z!$I
6<1$+&3Ic-1<*k!0!E!F$p!B!0!"P
3-V!0!HV-$I<0aOL!d*!A
2.3 Sơ đồ khối của phơng pháp ghép TDM :
<4 <9 <c <4
HP
E
*
HP
!&
3~
X
X
<
+&
3I
4
9
c
70!H$%& 70!HD!
Hình 1.10. Sơ đồ chu kỳ của hệ thống thâm nhập nhiều lần
với sự phân chia thời gian
LHX
,2
LHX
,2
eP/
-0!&
7P$
HP
HP
0
HP
&
0!$
HP
ePV/
!&
0
9kg;.H]
&
Hình 1.11: Sơ đồ khối kỹ thuật TDM
b
O4
b
O
!2c38&:a1PF,!&kuP3
2_`w2c3>-6=*w!E
•c×
$H
70!E32b
O4
b…
O
$+&$p!LHX,2HL$(1
$+&HO&_R.`!0!"$I
$H4
…
$H
:Dka$+&
3I!?*$01=-<*O&M@=&!-8&R.
eP/-0!&wHL$(uO&R.1i/H8k<-3-V
3
$H
!?*3n"*$E*&32c3!PO&$HPk
F,2w$p!$*$LLHX<&=+o<0!?*O&$HP!-
263&
ëHP&kF,2$p!$*iLHX<&=+.!$HP&
w$+&3I$I0!O&$HP1H0-&od*!$HP&1
$HP0!E)&*6L*&$I$VHV-F,M&d*0
1&3J!Ea*30!ePV/!&wHL$(uHP/H8
<-!0!3n"*:D1!0!O&R.*&$EkLHX,2
wM%MpB,!0!O&R.:D1HLE18&:a
&=&y
LHX,2VM1!n-*!+&
K7+&&6M1HL$(8&R*M-1!0!O&R.
K7+&p!M1HL$(!0!O&R.18&R*M-
,F,!E,!$P30!,!$P2k*V!&=I$(,!$P
Z2$p!n-&=l!2>.*V-<*!0!3n"*
$H
.u3n"*!D*$aHP/!?*!0!&8&30!*&I
-<*!0!3n"*!-!0!&8&30!*&"*[YHP
B$"K"*O&k$p!HI&jZw*&
•c×
$H
. . .
!3 4
9
n4
. . .
$H4
n9
$H9
. . .
n
$H
. . . . . . . . . .
2.4 CÊu tróc ph©n cÊp cña hÖ thèng sè:
I<&=+d8&$/$p!/-0V%30!*&1d8
&,,!$P<&=+30!*&)&*!0!:<&=+,30!
*&7EP)&=!!&+!@&<A!B!@!?*,>.oE$p!Q
M1!@&<A!B!@!?*,,
Zw*&!r<*!@&<A!B!@!?*,,!&t7B&€&-
77'3&=LX
H×nh 1.12 : §å thÞ thêi gian cña bé ph©n ®êng (thêi gian xung)
4
9
7@'
.
.
.
G;3H]
7@
''
4
;
7@
'''
;
4
7@
'
;
4
4
7@
;
9kg;.H]
k;GG.H]
;kG.H]
4Žk9G;.H]
CGg.H]
H×nh 1.13 : CÊu tróc ph©n cÊp hÖ thèng sè ch©u ©u
,,7B&€&M@=8&-,M1,!$P!&t@@!?*
ZM1G;H
- 293-,1F:!@9kg;.H
- 2;39kg;.H1F,k;GG.H
- 1!D2;3!?*!@@*M$p!PF,!E,!$P!*-:
*!E!0!,!$PM12!@9;kG.H
2!@4Žk9G;.H
2!@;CG;kŽŽ9.H
70!8&,M&kB*kZV!E,!$P30!,!$P-V
$p!!&=I$(,!$P2$p!!0!8&-$I$*1-,
<&=+,,B*!EV%ig÷4C}k,!$PM1;Ho
$I!EI2$p!1-,ZEw!LP,3-9kg;.H
8&ZVig÷G.}k,!$P!EI$$L1< .HkEw
!LP34;;.Hh:0>7._>ˆn<n*M&Mnn
7-n &M*-`Z,!$PZV!r•:-W!Hs†g.H$Ek
*!EI2*3ZV1-P34;;.H
c-1<*k77'!F3&=LX!@&<A!B!@,30!$*$p!
h#P,,,
K7@&<A!B!@,!?*,,el!.5
'
'
'' '''
G;H]
H×nh 1.14 : S¬ ®å biÓu diÔn cÊu tróc ph©n cÊp cña hÖ thèng B¾c MÜ
Gk49.H] ;;k†G.H]
9;†k4†G.H]
4kC;;.H]
c6=k@!V!0!!@&<A!B!@,$+&M@=,!$P-G;HM1
,!$P!&t@@o$B=!8M1,!$P!:HV$I21-D!!*-:
2.5 Tæ chøc ghÐp TDM cã dßng sè 64 Kbps:
n-&!&t77'k$I$$p!,!$P9kg;.H"*29
3-,G;H
c6=k*!E,!$PH8(!?*,M1
93×G;H•9kg;.H
7n-77'P3&"*!&t!-93n"*D
93*&
c"*(!D!P$*3&_.`4G3&19$0,M%Mp
ig$L4C"*!?*P3&M149Cµ!D*93n"*ig
$L41u3n"*1kŽµPi/H8k"*PH8
1;
<-,93n"*Z
g1!-8&$HP3&1$+&3I
4G1!-H0-&
8&$HP3&
<-!0!3&M•
*3&9
g 4 ; † 9 C Ž 4g 49 4;4
Ž
G 44 4C
!
4
!
g
!
9
!
!
4C
!
4G
!
4†
!
g
!
4
!0!3- !0!3-
!0!
3&
!0!3n
"*
H0-&
H×nh 3.8 Tæ chøc khung PCM 30 kªnh
4÷4Ck4†÷41!-g3-
!0!3&!•kH$HP<-g!EUgg4gg44
!0!3&M•kH$HP<-g!EU4RUUUUU
<-$EUK!0!H3J$p!BH,H#77'!-H@!D!D!
$W!H1-1"$p!$WM14
RKH8H0-<0$HPk"M1g$(43
@$HPOV=<*
4GM1P3!r$X<!-!<&=+-W!H0-&3!&
-W!H0-&3<!-PE!0!3-Y&P!
<-<"pH0-&3!&k4G!?*Q3&$p![Y
M13H0-&!E,!$PG;H,!0!,H0-&33L
pk4G$p![Y*&
4G!?*3&g$p![Y$I2(p$HP$*3&18
&!rX@$HP$*3&(p$HP$*3&ggggk$p!lOL
1!Y1-!0!H8i4÷;o!0!H8Ck†k1M&J!ED!M-!4
7rX$HP$*3&I#DG
43@$HP$*3&
g3$HP$*3&$A
HP$*3&$p!OnM1@3*(p$*3&MLHX*
8@PMu-W!3@!V!0!H8iC÷!?*3n1=$+&M1gV
$HP$*3&VV$p!"3I<*3Lp!V*$+&3E<
n4G!0!3&30!$p![Y$IZ1*3H0-&3
3Lpk,!$Pu3M1gH
III. ChuyÓn m¹ch sè
1. Kh¸i qu¸t hÖ thèng chuyÓn m¹ch :
7D! !&=I!!?*($1M1$ILM6&=L,d***=
+&&H*-<-!h($1-W!d*($11=($130!
<!:#&=L,$/$p!LM6kLHX!&=I!a!<&=+
LE18&H0-&d*!0!&H*-$P!6=1!8O0!#
D!!-2*=,!&=I!!?*!0!($1M1!&=I
!,ZE!E+&&$I<-3*0!
7&=I!,M1)&0<ZM3L!0!3n"*d*P,!0!M
3L<&=+35&6,>.
7
,
!&=I
!,
70!
&=L
7.
<*
H×nh 3.1 : Vai trß cña khèi chuyÓn m¹ch sè
70!
&=L
7.
1-
7.g
7.4
7.
7.g
7.4
7.
W!$I(H6!?*!0!($1!&=I!,M1P&=L6MN$p!
[Y!&!-P,!&P!Q<!:#B!*n-"*[Y
E.u!&P!Q[Y&=L1=<-P3-V"*O0!$X1
n-!&3Z,!$PMW8!p,8&-k,!$PMWM1}o
D!M1!Du3-V"*49CµM<&=+$LE_!?*!&P!Q$/$K
p!LM6`PM%LE<-uM%<&=+$QM1P&1$p!
/-0n-:D!7.
cE!&kP,!&=I!,Y!YP,&D!$/$K
p!23n-"*70!38&7.1=$p!<&=+<!0!
&=L7.<!0!&=L7.!&$EV$+&3J
_LE1H0-&`1!0!31=$p!0!<*n-&=MNB3
n-"*q&0<Z210!37.$p!a!H#!0!LHX
210!3<!1*&LHX!&=I!
2. C¸c ph¬ng thøc chuyÓn m¹ch sè:
I$@&,*&H*-*&!%V<*-$(3n"*!?**
&LEo!0!&1=!EI<!hP&=L7.-W!#!0!&=L
7.30!*&1$/$p!/-07E*:0a!!&=I!
!0!(p/1=n-*k$EM1!&=I!3J*1!&=I
!"*
2.1 ChuyÓn m¹ch kh«ng gian:
g
4
g
4
.*<6L
$I!&=I
!
H×nh 3.2: S¬ ®å khèi chuyÓn m¹ch kh«ng gian
eP$+&
3I
‘g
‘4
‘9
‘
Ug U4 U
H×nh 3.3 : S¬ ®å nguyªn lý chuyÓn m¹ch ®iÒu khiÓn ®Çu ra
.P!&=I!3J*,H*-P*<6>.!0!
,7.1-1<*a!Lk*<61="M1*<6&Jƒ*M1
&=L7.1-Hs&=L7.<*o&=L1=!Ei9CG4g9;
3n"*&~n-!@&<A!1)&=J!?*HP!&=I!
70!-$P<-u!P$p!$+&3IH#PHP$+&3I_7.`o
,MpJ!?*uHP1=Hs,3n"*!?*u&=L7.
.P$X*!rXB&=@$p!01-u-$P<-P!P
$I$VHV-!rPL$I<-u!P$p!J!<-3-VP
3n"*,H8XB<-uJ$p!O0!$XH#
•M-
9
c
<-$E,H8!?*uJ
c,Mp&=L7.$%&1-
q&0<Z$+&3I!&=I!$p!L1*&7.w$Q!<*P
&Pi/$X*!r1-$E<-3-V"*:D!?*u3n
"*1h$X*!r1=$I!QPQ*$P1E$p!d#<08!
!a!_,`<-&,"*!?*3n"*1=q&0<Z1=LY!!-
$L3uX<8<-7.$/$p!$Q!1-$P8!p$/$p!38!-
7J!$Q!$p!L1n-!&3Zku!&3Z!L3-V"*
!?*P3&o<-3-V"*1=Pi/7._H`<-u
3n"*#{1-$p!!&=I!$L3n"*:D#{<*
IVE&=L,kHP$+&3I<&BwO-0P&$X*!r
#J$+&3I:D3n"*1!-&=L,$Ek
L$I!&=I!:D3J6$p!M#d*1!<&=+
!0!i/7.iMk&=L,HX!l
2.2 ChuyÓn m¹ch thêi gian :
7&=I!"*M1a6!&=IP&<-P3n"*
1=$L3n"*30!k3J@LV<h!r,q&0<Z1=
M)&*$LaO&@P"*<j8!p<-P!&=I!
"*
+!@&-kHP!&=I!"*8&,*HPoPHP
LE1PHP$+&3I
fePLE!E,Mp!0!JHs,Mp3n"*$p!
2<-3&!?*&=L7.$*1-.uJ#HPLE!E
H8*J!?*ui/7.$!-P&8&L
E
feP$+&3I!E,MpJHs,MpJ!?*HP
LEuJ!?*E!E,MpH8&~&P!,Mp3n"
*!?*!0!&=L27.
7A!E)&**&n-HI&D!
9
<
•7
<-$E<,H8!?*PJ#HP$+&3I
7,Mp3n"*!?*&=L27.
*HPLE1$+&3I!?*HP!&=I!"*,M3L
*&J)&*,H&$X*!r1!X&a$+&3I!?*HP$+&3I
!&=I!-W!<a!L-W!J)&*HP$L3n"*
eP$+&
3I
!&=I
!
eP$L
3n"
*
H×nh 3 .4 : Nguyªn lý chuyÓn m¹ch thêi gian
ePLE
&=L7.<*&=L7.1-
eP$+&3I
e&$X*!r
I$+&3I$p!!&=I!"*k!E*:0a!
- +&3I!&=I!$%&1-
- +&3I!&=I!$%&<*
2.2.1 §iÒu khiÓn chuyÓn m¹ch ®Çu vµo
ë:D!1=k!0!&8&7.i$%&1-$*$p!1-HP
n-:0!E$+&3•oD!M1<Za!0!&O&7.#!0!
3n"*!?*&=L7.$%&1-1-!0!J1-!?*HPL
EM1-HP$+&3I)&=L$X>-$EuJ!?*HP+&3I
$p!M3L!W!w3n"*:D!?*&=L27.1-1
!D*$X*!r!?*3n"*!%$@&,#&=L27.<*q&0<Z
$Q!!0!&8&/-07.iHPLE1-!0!3n"*!?*
&=L7.$%&<*$p!L1n-<Zaa!?*HP$L3n"
*
2.2.2 §iÒu khiÓn chuyÓn m¹ch ®Çu ra
!$+&3I&=L,)&*<"!&=I!!J)&*)&0
<Z1$Q!#HPLE1HP$+&3Ic)&0<Z
!0!i7.i&=L7.$%&1-$LHPLE_.`M1&%a1
$p!$+&3IH#HP$L3n"*
-$P$Q!<*iHPLE)&=L$XH#HP$+&3IoHP
$+&3Iw6!0!MiHP$+&3I!&=I!$I)&=L$X
&=L,1-$p!,!-&H*-
3. C¸c cÊu tróc cña khèi chuyÓn m¹ch sè :
<!Lk*O2$Ld&p!$I!?*%!&=I!"*1
%!&=I!3J*
3.1 §èi víi tÇng chuyÓn m¹ch thêi gian
.P$W!$I(H6@!?*%!&=I!"*$EM1$P<j
<&=+<-)&0<Z<*-$(3n"*<!0!&=L7.1-1
&=L7.<*