Tải bản đầy đủ (.pdf) (91 trang)

Nghiên cứu kỹ thuật đa điều chế cho bộ biến tầng đa bậc

Bạn đang xem bản rút gọn của tài liệu. Xem và tải ngay bản đầy đủ của tài liệu tại đây (6.22 MB, 91 trang )


$,+2&482Ê&*,$73+2Â
&+0,1+


75áả1*$,+2&%$ằ&..+2$






1*8<(Ơ17+$1+1+$Ô1



1*+,(Ô1&áằ8.<Ã7+8$Ư7$,(Â8&+(Ê
&+2%2Ư%,(Ê17$Â1$%$Ư&





&+8<(Ô11*$1+.<Ã7+8$Ư7,(Ư1
0$Ã62Ê1*$1+




/8$Ư19$ơ17+$&6à







73+R&Kẽ0LQKWKDQJQDèP



DẹL+RẹF4XRF*LD7S+R&Kẽ0LQK
75áả1*$,+2&%$ằ&+.+2$




&2Ư1*+2$;$Ã+2Ư,&+8ẵ1*+à$9,(Ư71$0
RặFODặS7ỉẹGR+DẹQKSKXF
73+&0QJD\WKDQJQDèP

1+,(Ư098/8$Ư19$ơ17+$&6à












+RẹYDWHQKRẹFYLHQ 1*8<(Ơ17+$1+1+$Ô13KDL1DP
1JD\VLQK
 



1ệLVLQK7LHQ*LDQJ
&KX\HQQJDQK
.\ìWKXDặWểLHặQ


06+9.7,
,7(Ô1(Â7$,
1*+,(Ô1&áằ8.<Ã7+8$Ư7$,(Â8&+(Ê&+2%2Ư%,(Ê17$Â1$%$Ư& 
,,1+,(Ư0989$12Ư,'81*
ã 7ẻPKLHầXN\ìWKXDặWểDểLHXFKHFKRERặELHQWDQểDEDặF
ã $SGXẹQJN\ì WKXDặWểDểLHXFKH ểệQVRQJPDQJ600FKRELHQWDQEDặFGDẹQJ
FDVFDGH
ã .KDíRVDWWẽQKRầQểễQKệí[DFODặSFXíDFDFểDSỉQJWDíLNKLVỉíGXẹQJELHQWDQEDặF
GDẹQJFDVFDGH
,,,1*$<*,$21+,(Ư098 
,91*$<+2$17+$1+1+,(Ư098
9&$ằ1%2Ư+áảằ1*'$Ơ1761*8<(Ơ19$ơ11+ả 














761*8<(Ơ19$ơ11+ả








1RặL GXQJ YD ểH FỉệQJ OXDặQ YDèQ WKDẹF Vế ểDì ểỉệẹF +RặL RQJ &KX\HQ 1JDQK WKRQJ
TXD












75áảẵ1*3+21*76+






 












1JD\WKDQJQDèP
75áảẵ1*.+2$4/1*$1+








&2Ô1*75đ1+áả&+2$17+$1+7$,
75áả1*$,+2&%$ằ&+.+2$

$,+2&482Ê&*,$7+$1+3+2Ê+2Â&+0,1+



&DQERặKỉệQJGDQNKRDKRẹF7LHQVế1*8<(Ơ19$ơ11+ả


&DQERặFKDPQKDặQ[HW


&DQERặFKDPQKDặQ[HW






/XDặQYDèQWKDẹFVếểỉệẹFEDíRYHặWDẹL+2Ư,2Â1*&+$Ê0%$ẵ29(Ư/8$Ư19$ơ1
7+$&6à75áả1*$,+2&%$ằ&+.+2$QJD\WKDQJQDèP









&RWKHầWKDPNKDíROXDặQYDèQWDẹL
7KỉYLHặQ75áả1*$,+2&%$ằ&+.+2$

$,+2&482Ê&*,$7+$1+3+2Ê+2Â&+0,1+



 ✂✁☎✄☎✆✞✝ ✟✡✠ ☛✌☞ ✍✏✎ ✑✓✒ ✔ ✕✗✖☎✘✚✙ ✛✢✜ ✣✥✤ ✦✂✧✞★ ✩✡✪ ✫✌✬✮✭ ✯ ✰✲✱✮✳ ✴✲✵✷✶ ✸✢✹ ✺✼✻ ✽✢✹ ✾✥✻ ✿❁❀

0ảẵ$Â8
1JD\ QD\ FDF WKLHW Eễ ểLHặQ Wỉí FRQJ VXDW UDW ĨØƯĐF TXDQ WDÄP YDÚ VØÝ GXĐQJ
WURQJ QKLHÂX ÕQK ỲĐF NKDÛF QKDX QKØ KHỈ WKRÃQJ WUX\HÂQ WDÝL KHỈ WKRÃQJ SKDÄQ SKRÃL
ĨLHỈQ QDèQJ GXQJ WURQJ FRQJ QJKLHặSg 9D PRặW WURQJ QKỉìQJ ỉQJ GXÑQJ FXÝDQRÛ ODÚ
GXÚQJ FKR FDÛF ØÛQJ GXÑQJ FRÛ FRÄQJ VXDÃW FDR 'R ểR ểLHặQ DS YD GRQJ ểLHặQ SKDíL
ểỉệẹFQDQJOHQWỉệQJỉQJ9ẻYDặ\PD FRQJVXDWểễQKPỉFFXíDOLQKNLHặQEDQGDQ
VHìODPRặWWUệíQJDẹL1JRDLUDFKXQJWDNKRFRWKHầVỉíGXẹQJFDFOLQKNLHặQEDQGDQ
FRQJVXDWWUỉẹFWLHSYệLOỉệLểLHặQWUXQJDSKD\FDRDS .9
PDFDQ
FR JLDíLSKDSWRWKệQQKỉOD ELHQWDQểDEDặFểHầ FR WKHầ ODPYLHặFYệLFDSểLHặQDS
FDRKệQ.KLểRểLHặQDSFXQJFDSFKRWKLHWEễVHìểỉệẹFểLHXNKLHầQWRWKệQ
+LHặQ QD\ QKLHX SKỉệQJ SKDS ểLHX NKLHầQ FKR ELHQ WDQ ểD EDặF ểDì ểỉệẹF
QJKLHQFỉXYD ỉQJGXẹQJểLHầQKẻQKQKỉSKỉệQJSKDSểLHXFKH ểRặ URặQJ[XQJVLQ
63:0YDSKỉệQJSKDSểLHXFKHYHFWRUNKRQJJLDQ693:0ểDìFKRPRặWVRNHW
TXDí QKDWểễQK7X\QKLHQFDFSKỉệQJSKDSQD\FXìQJJDSSKDíLQKỉìQJSKỉFWDẹS
WURQJYLHặFểLHXNKLHầQGRểR NHWTXDí WKXểỉệẹFFXìQJFRQKDẹQFKH9D PRặWWURQJ
QKỉìQJSKỉệQJSKDSểLHXNKLHầQFKRELHQWDQểDEDặFFR WKHầ FKRSKHSWKỉẹFKLHặQ
ểLHXNKLHầQPRặWFDFKểệQJLDíQKệQQKệ Vỉẹ KRầ WUệẹ FXíDN\ì WKXDặWVR FXìQJQKỉGỉẹD
YDRQKỉìQJOệẹLểLHầPFXíDSKỉệQJSKDSWUHQODN\ìWKXDặWểDểLHXFKH00 PXOWL
PRGXODWLRQ

;XDWSKDWWỉYLHặFQD\PD\HXFDXểDWUDFKROXDặQYDèQQD\
ã 1JKLHQFỉXN\ìWKXDặWểDểLHXFKHFKRELHQWDQểDEDặF
ã $S GXẹQJ N\ì WKXDặW ểD ểLHX FKH ểệQVRQJPDQJểHầ ểLHXNKLHầQELHQ

WDQEDặFGDẹQJFDVFDGH
ã .KDíR VDW WẽQK RầQ ểễQK ệí [DF ODặS FXíD FDÛF ĨDÛS ØÛQJ WDÝL NKL VØÝ GXĐQJ
ELHÃQ WDÂQ EDỈF 7URQJ ểR ELHQ WDQ EDặF  GDẹQJ FDVFDGH YD ểRặQJ Fệ
ểRQJERặNẽFKWKẽFKQDPFKDPYẩQKFỉíXGXQJểHầNKDíRVDW

7UDQJ


❄✂❅☎❆☎❇✞❈ ❉✡❊ ❋✌● ❍✏■ ❏✓❑ ▲ ▼✗❆☎■✚◆ ❖✢€ ◗✥◆ ◗✂❇✞❈ ❘✡■ ❋✌❆✮❈ ❙ ❋✲❆✮❚ ❯✲❇✷❈ ❙✢❊ ▼✼◆ ❘✢❊ ◗✥◆ ❯❁◆


&+áả1* %,(Ê17$Â1$%$Ư&

*,ảằ,7+,(Ư8
9H Fệ EDíQ ELHQ WDQ ểD EDặF JRP FDF GDì\ OLQK NLHặQ EDQ GDQ FRQJ VXDW YD
FDFQJXRQDSSKXẹWKXRặFYDREDặFFXíDELHQWDQ7KXDặQOệẹLFXíDELHQWDQểDEDặFVR
YệLELHQWDQEDặFWUX\HQWKRQJOD ểLHặQDSQJRì UDVHì ểỉệẹFFDíLWKLHặQWRWKệQGR
VR EDặFểLHặQDSOD QKLHXKệQ9ẻYDặ\ELHQWDQFR EDặFFDQJFDRWKẻểRặ PHRGDẹQJ
KRẹDWDQệí ểLHặQDSQJRì UDFDQJJLDíPERặ ORẹFểLHặQDSệí QJRì UDELHQWDQVHì QKRÝ
KƯQ ĨLHỈQ DÛS FKƠX ĨØĐQJ YDÚ WDÂQ VRÃ ĨRÛQJ FDËW FXíD FDF OLQK NLHặQ ểRQJ FDậW FXìQJ
JLDíP7X\QKLHQPỉFểRặSKỉFWDẹSFXíDELHQWDQODWDèQJOHQ
+ẻQKYHì GỉệLểD\FKRWKD\ểLHặQDSVLQệí QJRì UDFXíDELHQWDQểDEDặFOD Vỉẹ
WRầQJKệẹSFXíDQKLHXFDSểLHặQDS ELHQWDQEDặF



+ẻQKLHặQDSQJRìUDELHQWDQEDặF

7UDQJ



❲✂❳☎❨☎❩✞❬ ❭✡❪ ❫✌❴ ❵✏❛ ❜✓❝ ❞ ❡✗❨☎❛✚❢ ❣✢❤ ✐✥❢ ✐✂❩✞❬ ❥✡❛ ❫✌❨✮❬ ❦ ❫✲❨✮❧ ♠✲❩✷❬ ❦✢❪ ❡✼❢ ❥✢❪ ✐✥❢ ♠❁❢
&$ằ&/2$,%,(Ê17$Â1$%$Ư&
%LHQWDQểDEDặFWKỉệQJểỉệẹFSKDQORDẹLWKHRFDXWUXFVệểRFXíDQRWKỉệQJ
WKẻFREDGDẹQJSKRầELHQOD
'DẹQJGLRGHBFODPSHGLQYHUWHU
'DẹQJFDSDFLWRUBFODPSHGLQYHUWHU KD\IO\LQJFDSDFLWRU

'DĐQJFDVFDGHGLQYHUWHU

'LRGHB&ODPSHG,QYHUWHU
%LHÃQWDÂQEDỈFGDQJGLRGHBFODPSHG KD\JRĐLODÚ 13&FRQYHUWHU
ểỉệẹFJLệL
WKLHặXYDRQDèP


+ẻQK%LHQWDQEDặFGDẹQJGLRGNHẹS

6DX ểR GDẹQJ QD\ ểDì ểỉệẹF Pệí URặQJ WKDQK GDẹQJ ELHÃQ WDÂQ EDỈF FDR KƯQ QKØ
EHÄQGØỬL


7UDQJ


♦✂♣☎q☎r✞s t✡✉ ✈✌✇ ①✏② ③✓④ ⑤ ⑥✗q☎②✚⑦ ⑧✢⑨ ⑩✥⑦ ⑩✂r✞s ❶✡② ✈✌q✮s ❷ ✈✲q✮❸ ❹✲r✷s ❷✢✉ ⑥✼⑦ ❶✢✉ ⑩✥⑦ ❹❁⑦

+ẻQK%LHQWDQEDặFGDẹQJGLRGNHẹS




'LRGHBFODPSHG PXOWLOHYHO LQYHUWHU Vỉí GXẹQJ PRặW QJXRQ ểLHặQ DS GF FKLD
UDQKLHXEDặFDSGFEệíLFDFWXẹ ểLHặQPDậFQRLWLHS9D GỉẹDWUHQFDFGLRGHểHầ
FRểễQKEDặFểLHặQDSệíQJRìUDệíểD\PRLEDặFWỉệQJỉQJYệLPỉFểLHặQDSWUHQ
PRLWXẹểLHặQWURQJEXVGF
6ệểRFKỉFQDèQJFXíDELHQWDQQD\FRWKHầểỉệẹFWKHầKLHặQQKỉVệểR+GỉệL
ểD\

7UDQJ


❻✂❼☎❽☎❾✞❿ ➀✡➁ ➂✌➃ ➄✏➅ ➆✓➇ ➈ ➉✗❽☎➅✚➊ ➋✢➌ ➍✥➊ ➍✂❾✞❿ ➎✡➅ ➂✌❽✮❿ ➏ ➂✲❽✮➐ ➑✲❾✷❿ ➏✢➁ ➉✼➊ ➎✢➁ ➍✥➊ ➑❁➊

+ẻQK6ệểRWỉệQJểỉệQJFXíDELHQWDQEDặ FGDẹQJGLRGNHẹS



9ệLFRQJWDậFQYễWUẽWUHQPRLSKDFR
n 1

S
j =0

ij

= 1  

YệL i = {a, b, c}





1HXểLHặSDSSKDQERWUHQFDFWXẹểLHặQODFDQEDấQJWKẻ

V DC n1
vio =
jS ij  YệL i = {a, b, c}
n − 1 j =1
 












Q%DặFFXíDELHQWDQ

9ẽGX
'DẹQJVRQJểLHặQDSQJRìUDFXíDELHQWDQểDEDặFGDẹQJQD\YệLểLHặQDSWUHQFDFWXẹ
ểLHặQODFDQEDấQJ

7UDQJ



➓✂➔☎→☎➣✞↔ ↕✡➙ ➛✌➜ ➝✏➞ ➟✓➠ ➡ ➢✗→☎➞✚➤ ➥✢➦ ➧✥➤ ➧✂➣✞↔ ➨✡➞ ➛✌→✮↔ ➩ ➛✲→✮➫ ➭✲➣✷↔ ➩✢➙ ➢✼➤ ➨✢➙ ➧✥➤ ➭❁➤

+ẻQK&DFPỉFểLHặQDSSKD$QJRìUDFXíDELHQWDQ
YệLFDFWUDẹQJWKDLểRQJFDậWNKDFQKDX

ã &DFểDFểLHầPFXíDELHQWDQểDEDặFGDẹQJGLRGHBFODPSHG
B6RWXẹểLHặQODẽWQKỉQJSKDíLWKHPGLRGHNHẹSWURQJVệểR
B&RWKHầVỉíGXẹQJPRặWQJXRQDS'&
B.KLELHQWDQFREDặFOệQKệQWKẻểLHặQDSPDGLRGHNHẹSSKDíLFKễXểỉẹQJ
OD 9 Q
 Q
FDR'RểR VHì SKỉFWDẹSWURQJWKLHWNH QKỉSKDíLNHWQRL
QRLWLHSFDFGLRGH
B 9DQ ểH NKRQJ FDQ EDấQJ ểLHặQ DS FDF WXẹ ểLHặQ ệí ELHQ WDQ ểD EDặF GDẹQJ
QD\FRWKHầJD\UDTXDDSWUHQPRặWKD\QKLHXOLQKNLHặQểRQJFDậW
&DSDFLWRUB&ODPSHG,QYHUWHU
&XìQJWỉệQJWỉẹQKỉGDẹQJGLRGHBFODPSHGệíểD\FDXWUXFVệểRJRPFDFWXẹ
ểLHặQểỉệẹF[HSOệSOHQQKDXPD NKRQJFR FDFGLRGHNHẹSLHặQDSQJRì UDOD
NHWKệẹSFXíDFDFWXẹểLHặQểỉệẹFPDậFQRLWLHSWUHQVệểR

7UDQJ




➸✂➺☎➻☎➼✞➽ ➾✡➚ ➪✌➶ ➹✏➘ ➴✓➷ ➬ ➮✗➻☎➘✚➱ ✃✢❐ ❒✥➱ ❒✂➼✞➽ ❮✡➘ ➪✌➻✮➽ ❰ ➪✲➻✮Ï Ð✲➼✷➽ ❰✢➚ ➮✼➱ ❮✢➚ ❒✥➱ Ð❁➱ ẹ


+ẻQK%LHQWDQEDặFGDẹQJWXẹNHẹS


+D\VệểRWỉệQJểỉệQJSKD$


+ẻQK6ệểRWỉệQJểỉệQJSKD$FXíDELHQWDQGDẹQJWXẹNHẹS



ảẵ ểD\WKẻKRDFFRQJWDậFWUHQ6ềễể KRDFFRQJWDậFGỉệL6ếìệ ệí PRLFDSVHì ệí
WUDẹQJ WKDL 21 1KỉQJ FDí KDL FRQJ WDậF QD\ NKRQJ ểỉệẹF FXQJ WUDẹQJ WKDL WDẹL
FXQJWKệLểLHầPYẻVHìJD\UDQJDậQPDẹFKệíFDFWXẹểLHặQ
9ẽGXẹ
%DíQJ WUDĐQJ WKDÛL ĨRÛQJ FDËW FRÛ WKHÇ FRÛ FXÝD FDÛF FDÍS FRÄQJ WDËF FKR ELHÃQ WDÂQ 
EDỈFGDĐQJFDSDFLWRUBFODPSHG

7UDQJ


ỉĩ íị ò ỏõ óọ ồ ổõỗ ốộ ờỗ ờĩ ởõ òĩ ỡ òớ ợĩ ỡị ổỗ ởị ờỗ ợỗ ốù


%DíQJ0ỉFểLHặQDSQJRìUDSKD$ỉQJYệLFDFWUDẹQJWKDLểRQJFDậWFRWKHầFR

ã &DFểDFểLHầPFXíDELHQWDQểDEDặFGDẹQJFDSDFLWRUBFODPSHG
B1KỉệẹFểLHầPFKẽQKFXíDELHQWDQểDEDặFGDẹQJQD\OD VR OỉệẹQJWXẹ ểLHặQWURQJ
VệểRODQKLHX
B0RLQKDQKFR WKHầ ểỉệẹFSKDQWẽFKểRặFODặSYệLFDFQKDQKNKDF.KRQJQKỉ
ELHQ WDQ ểD EDặF GDẹQJ GLRGHBFODPSHG NKL SKDQ WẽFK SKDíL TXDQ WDPểHQFDQ
EDấQJểLHặQDSệíEDSKDQJRìYDR
B*LDWUễFDFWXẹểLHặQODFDRGDQWỉWXẹOệSWURQJFXQJWệLWXẹOệSQJRDLFXQJ9ẽ
GXẹ&ũủ 

&úừụ 
&DVFDGHG,QYHUWHU
&DVFDGH PXOWLOHYHO LQYHUWHU JRÂP QKLHÂX FDÂX QJKƠFK ÒX ĨDÂ\ ĨXÝ PRỈW SKD
QRLWLHSQKDXYD PRLFDXQJKễFKOỉXQD\Vỉí GXẹQJPRặWQJXRQDSGFểRặFODặS
7KRQJWKỉệQJQJXRQGFQD\ểỉệẹFOD\WỉPD\ELHQDSFRQKLHXFXRặQGD\WKỉ
FDSểRặFODặSKRDFWỉQKLHXELHQDSULHQJELHặW

+ẻQK%LHQWDQểDEDặFGDẹQJ&DVFDGH 

7UDQJ




ửữứựỳ ỷỹ ýỵ



ựỳ ýứỳ ýứ ựỳ ✑✢ü ✝✕✟ ✎✢ü

✂☎✄ ✆ ✝ ✞ ✠✟ ✡☞☛ ✌✍✟ ✌

✌✍✟ ✔✖✟

RLYệLELHQWDQểDEDặFFR EDặFFKDĩQWKẻSKDíLWKHPYDRERặ QJKễFKOỉXNKRQJ
ểD\ểXíYDRFDXWUXFFXíDVệểR
9ẽGXẹ%LHQWDQEDặFGỉệLểD\


+ẻQK%LHQWDQEDặFGDẹQJFDVFDGH


ã &DFểDFểLHầPFXíDELHQWDQểDEDặFGDẹQJFDVFDGHGLQYHUWHU
B'DẹQJELHQWDQQD\OD NKRQJFDQWKHPGLRGHKD\WXẹ ểLHặQQKỉELHQWDQểD
EDặFGDẹQJGLRGHBFODPSHGWX\QKLHQVREDặFểLHặQDSQJRìUDFXìQJWỉệQJWỉẹ
B6R EDặFểLHặQDSFR WKHầ WDèQJOHQGHầ GDQJEDấQJFDFKPDậFQRLWLHSWKHPFDX
QJKễFKOỉXYDR
B%LHQWDQGDẹQJFDVFDGHODẹLFDQQKLHXQJXRQGFểRặFODặSWUHQPRLERặ QJKễFK
OỉXWURQJNKLGDẹQJGLRGHBFODPSHGWKẻFRWKHầFKẩFDQPRặWQJXRQGF
BHầFDQEDấQJFRQJVXDWFKRFDFQJXRQGFWKẻFRWKHầWXDQKRDQVỉíGXẹQJFDF
QJXRQGFWURQJFKXN\9LHặFQD\ODPFKRWDQVRểRQJFDậWFDFOLQKNLHặQEDQGDQ
WURQJVệểRFXìQJFDQEDấQJ

7UDQJ


✘✚✙✞✛✞✜✣✢ ✤✏✥

✦★✧ ✩✁✪

✫☎✬ ✭ ✮✯✛✞✪✠✰ ✱☞✲ ✳✍✰ ✳✚✜✣✢ ✴✏✪

✦★✛✓✢ ✵

&$ằ&3+áả1*3+$ằ3,(Â8.+,(Đ1
7ỉệQJỉQJYệLFDFORDẹLELHQWDQểDEDặFWKẻFDQFR FDFSKỉệQJSKDSểLHX
NKLHầQ ểLHX FKHÃ WKÏFK KƯĐS &DÛF SKØƯQJ SKDÛS ĨLHÂX FKHÃ QDÚ\ FX×QJ FR WKHầ ểỉệẹF
SKDQORDẹLWKHRWDQVRểRQJFDậW1RLFKXQJWKẻFRKDLSKỉệQJSKDSSKRầELHQQKDW
GXQJFKRELHQWDQểDEDặFOD SKỉệQJSKDSểLHXFKH ểRặ URặQJ[XQJVLQ 63:0

YDÚSKØƯQJSKDÛSĨLHÂXFKHÃYHFWRUNKRÄQJJLDQ 690


.KLODPYLHặFYệLWDQVR ểRQJFDậWFDRWKẻSKRầ ELHQOD SKỉệQJSKDSFRầ ểLHầQ
63:0YD EDấQJFDFKGễFKFKX\HầQSKDVRQJPDQJFXìQJQKỉVRQJểLHXFKH ểHầ
JLDíPPHRGDẹQJệíểLHặQDSQJRìUD
.KL ODP YLHặF YệL WDÂQ VRÃ ĨRÛQJ FDËW WKDÃS KƯQ  WØÛF FKÈ FRÛ PRặW KRDF KDL ODQ
ểRQJ FDậW ệí OLQK NLHặQ EDQ GDầQ FRÄQJ VXDÃW WURQJ PRỈW FKX N\Ú ĨLHỈQ DÛS FƯ EDÝQ
 WKẻ
SKỉệQJSKDSểDẹLGLHặQODểLHXNKLHầQYHFWRUNKRQJJLDQ69&
'RKDLORDẹLELHQWDQểDEDặFSKRầ ELHQQKDWOD GDẹQJGLRGHBFODPSHGYD GDẹQJ
FDVFDGHQHQệí ểD\FKẩJLệLWKLHặXFDFSKỉệQJSKDSểLHXNKLHầQWKỉệQJJDSệíKDL
ORDẹLQD\
ã RLYệLELHQWDQểDEDặFGDẹQJGLRGHBFODPSHGWKẻSKỉệQJSKDSSKRầ ELHQ
QKDW OD 63:0 WKHR SKØƯQJ SKDÛS QDÚ\ FDÛF WUDĐQJ WKDÛL ĨRÛQJ FDËW FXÝD FDF
FDS OLQK NLHặQ EDQ GDầQ ểỉệẹF [DF ểễQK GỉẹD YDR SKDQ JLDR JLỉìD FDF VRQJ
PDQJWDPJLDFYDWẽQKLHặXểLHXFKHGDẹQJVLQ
%LHQ WDQ Q EDặF VHì FR Q

×