Phương pháp đánh giá hiệu năng của hệ thống CDMA quang vô tuyến

Đồ án tốt nghiệp Đại Học Lời mở đầu


 !"#$#%&'()
((*+,-./0/12!
#0!3 !4&-0(566(*4#783
(-#9/.9:';//</'=395 
#>$
?@5AB#>B/) :1.
/0/(B//,#CDEFG#
(H(*=":1$I3DEFG
JDEFG3(B//,#C=KL
/M1=60=0"#(5!3%0!4N
/0 $OB/(*"4@000PC0
#0Q0$?(6)03DEFG6
.=KL:#).&B/(74- .&
#$
:)4:>%(5)3DEFG
RS//.%01'/. *(6.T>U>/
)V 0!30(-U)
=MQ)6)4L)!W (S4="V#>$E#(6) 
!:1/&U3DEFG
@(00.&5U./0/DEFG#
;'!$
FL(:1U(70@(./0/(B//
,#C#$X!.L5U:
1(Y3JDEFG /&U3
Z=".TU0#>V V#>$KL0
LF4(5 [(7N.#=0P4,#0=30U
3$OB+<)(00":0!.(>(*$
:M=T%!1A#%&\B/:

OK]^V>I\ D_^VQ Z="
ZU`>NHI),(CY5):1 #
(703/ Z(a`M/0/(00&U3
DEFG !b$
_3L(707cM8
 
 
 !"#$%&'(()*+,
 -."("()#/*+,
GVHD: ThS. Phạm Thị Thúy Hiền SVTH: Trần Minh Phương – D08VT1
Đồ án tốt nghiệp Đại Học Lời mở đầu
FSQ(C;3d#>! S!1"!R
::dd(70U, 0e%!=6$f
;#B(*%g!(66/g40U0'(5(70(*
#M$
 :
 01(2
GVHD: ThS. Phạm Thị Thúy Hiền SVTH: Trần Minh Phương – D08VT1
Đồ án tốt nghiệp Đại Học Lời cảm ơn

O5#(*(70),+.M`>N
HI(CBYZ H/(h,#=30Y:1)
.M0'#_-^!]X#^Vi]I\ D
_^V)(S4OS!?\(C6%6/g
\#(70U,$O7,R+K.M==d(!(Y
432UYj%(C!k>#(3;#,#
(70$
 :
01(2
GVHD: ThS. Phạm Thị Thúy Hiền SVTH: Trần Minh Phương – D08VT1

Đồ án tốt nghiệp Đại Học Mục Lục

GVHD: ThS. Phạm Thị Thúy Hiền SVTH: Trần Minh Phương – D08VT1
Đồ án tốt nghiệp Đại Học Danh mục bảng, hình vẽ

GVHD: ThS. Phạm Thị Thúy Hiền SVTH: Trần Minh Phương – D08VT1
Đồ án tốt nghiệp Đại Học Thuật ngữ viết tắt

 !!"! #$! $%$& %&'(! $%)!
* G ,`###, E#,0
+, _f#l, m=3P4
 D4D#,,D#,= FC(74B4
+- f4E#/,4,G/n, _-!(>=*
/>/f4
+* f+,,`,D#,= FC:3T-
 ,n^=# o6Y
-/. ,,/,/## 
"#
 I/,4#D#,,D#, FC(7/,4#
0 i=,=F##jE,
E,,#
O!(-]0
=6"!/
 p=,E#, _-/0=,
 p,D#,,D#,= FC(7!
+ pfE#, E#,/0
. p#=# _-#(--
 F/,G,==i,n,,, ?V(B/
 F,#G,?,q#= F>(N
* F#n,`,D#,= FC:3=K(r

1** Fs ,,``F ``F(4Z=6
. /_,i,n,,, ?V##

. /D#,E =#F/,
G,==
OB//,#
C
. /p,t X3(
. /?,q#t X3>
 /##D#,= FC"#
2 ]nnX, X6(6jT
* `,D#,= FC:3
* `###, E#,0
*. `== ,/?,q#= F>L(-
** `=,`#=#F## O! N+
3 uD#,,D#,= FC(74B
/* ##=F#n,`,D#,= FC:3=K(r(74-
1 s ,,E =#F/,G,== OB//,#
4Z=#
1/2 s ,nX, X6N54Z=6
GVHD: ThS. Phạm Thị Thúy Hiền SVTH: Trần Minh Phương – D08VT1
Đồ án tốt nghiệp Đại Học Chương I: Tổng quan về hệ thống quang không dây
45637893
2:;<
1.1. =!&)>
3(-#(C ((6 k!=1\
#> V$(*v#>8
=* j,,/,/=$
D03=KL=*6.&
. Z*Z)!3Q ;/#>N

L#>)n+)Y.)=3$DQ6.&3(-#)
03Vd/(S)5#S!B/>;Y>
'$6(-## Y=KL'Yw,]#n]= 
ZU4H/=6#$D0+;'(': #
%&xyz{#01L="$O!3%&xy|{)%
=./}M>(C+; Y%#.
$D"d)*;/) ;( %w%4-/0 4-
R.TU!%>! #(6$
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SVTH: Trần Minh Phương – D08VT1 Trang 7
Đồ án tốt nghiệp Đại Học Chương I: Tổng quan về hệ thống quang không dây
Hình 1. 1: Sơ đồ khối hệ thống FSO thông thường
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 X336)-33(N

657>0!4N(C(*5$
 `0+>/.@#Z>#(N$
 \*2 e\$
 :L(&;/$
 ƒ:''Yw :!S[-!.U 
4H/=62/$
1.2. M&N$&&)!&I$%-/.
SVTH: Trần Minh Phương – D08VT1 Trang 8
Đồ án tốt nghiệp Đại Học Chương I: Tổng quan về hệ thống quang không dây
M(7rU-!(5Y(*5:Yx$v$o3
4;•#)374/'8_-/0):
 4-$D!0/'=[(*(B/Z($
Hình 1. 2: Sơ đồ khối của hệ thống FSO.
1.2.1. OP&?!
`'K6 L(!%3
=(6Z4-$`M1(!(*=KL-
C>4-/0(!(-iF)#(6(-/0+>U7
=[(*(!4T=3'($
^(!(*" (r"!/(-U
7>4-/0#S4-(!#4-##F]
„,,$^=KL-4-(!#@(.4.#3(-%(>
(*#M=# Z4-(!"!/$D0-0U41+>
/)'=3 >0/"R65(*=KL(5(!
ZQ Z%J =KL4-(!#$D07
 (SM4.UH(*:#4.x$x$
J=@KQ$%
R$DS
TU &@&V
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l‡ 6.L
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=;;/)3(-:Z…x{o4/=
…xˆ{{J…x††{ 4j`,#
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=3
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SVTH: Trần Minh Phương – D08VT1 Trang 9
Đồ án tốt nghiệp Đại Học Chương I: Tổng quan về hệ thống quang không dây
FB(-=;#M†{'
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O-3.{){ˆ]{)vsJG
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l; (->#
#=MQ3M
/'!>#6=‰
XB/U
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D=; 3(-%;/M
Bảng 1. 1: Các nguồn quang.

#.4Z=6Š{{jx{{{{6-=3K=r=6'
#=3 Z=#‹{)v_J$D03U!(*!!(5
#>(-#.Š|{]|†{ x†v{]xz{{$E.Š|{]|†{'
(*=KL-C4T Y!4N /'#.4Z=66=‰
/;/$E.x††{(* Y-=3g#=8.&M
 Z0></:/,#4Z=6K=r1ˆ)4.# d
=;/0>4Z=6x††{65;/†{'=# Z>|†{)
.(*&*S 0+>0=0#QJ=MQ$^Y B)
T.x††{65(*-=;(05 * =#4T
=MQ$:>!U.x††{(->.)/
#M :' ="=d/S[M$
x$v$v$ O!&>
_-P* /L0%(C(*/0(~//0$_-
4#70/'=8
3 46I(jB/*/ B/0/0+>Z4-0
=6$X}(-(-TU4-Z=[H/B/*/(*/0+>
 #4-0=6$
73 46JK#%(j_-\..*41+>$
#3 46"#:;j`i?#SG`E5(r(!
($D04-0=6(*Q#03
(*6d#4.x$v$
3 L#MNJOI(jD61&!(>)\ +Kg(5(.
4.#+0#U%(*/L$
SVTH: Trần Minh Phương – D08VT1 Trang 10
Đồ án tốt nghiệp Đại Học Chương I: Tổng quan về hệ thống quang không dây
E#.TU ( 4-0=6)04-0=63(-#
6ZeMŠ{Œ ˆ{ŒM1 Z3(-4v)†o4/=
x{o4/=)Q Z >! 6T)(ke="!3+0$o6T
^U4-m=3UZ4-0=6 :"$
^•d/f•dF#/D9#(6d(4-0=6)f(-

LU:") D(-TU4-$F#‚=3Uf$
O3 Z4-ZŠ†Œ)F#•x D•x†{)^•…{)†$
P"0Q"#:;&76#;C5R#9JGL(F
 Bộ thu tách sóng trực tiếpj#>4-/0(-1#S
=;/0+>(!4-0=6$^Y B)k(('U4-
0=6‚ Z=;UZ$^504-0
=6"!/;(M. ;/Q*/(3 Z03(
!(-$M(73U4-0=6"!/(*5#
Yx$ˆ$
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
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#`i? ˆ{{]xx{{ {)† x
#`i?) Z4-
!(>
=/,,
ˆ{{]xx{{ {)† x
ioG=`i? x{{{]xŠ{{ {)y x
#G`E c{{]x{{{ ŠŠ x†{
ioG=G`E x{{{]xŠ{{ y x{
Hình 1. 3: Sơ đồ khối của bộ thu quang tách sóng trực tiếp.
 Bộ thu tách sóng nhất quán (coherent)8_-0=6;06=M(7
3(*5#Yx$c ":*-=6
$Z(*!*/ Z(*>#>4-
SVTH: Trần Minh Phương – D08VT1 Trang 11
Bảng 1. 2: Bộ tách sóng FSO.
Đồ án tốt nghiệp Đại Học Chương I: Tổng quan về hệ thống quang không dây
#(--U4-$u0Y-=6(*":4
SU4-0=6$_-;065(*/#>
04-##, ,,#,$Ž04-##,)'=3J4Z

=6U4->##(--60N+0/0+>Z#
(64-0=6,,#,)/0+>Z 4->#=6-6'=30
$X0 Z4-/0;0=KL#=6 !)
('U4->#=6-#0=6;0:'
6Q/ Z=6Z$D0(5U-4-;0
8 !(>M(3V>'=3' "!m=3
:V6!(*.(05 V4@0&
=;4->##(--$
Hình 1. 4: Sơ đồ khối của bộ thu quang tách sóng nhất quán.
x$v$ˆ$ 2#$&M!>^ $
X:0=# Z:Vo==)
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Z(4-:(*8xt/. 0
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v
T
T
T
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3=;((* /M=UVrmM1
ZA
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d
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Q 0#>0UMZ$p*MZ6#:/L-
SVTH: Trần Minh Phương – D08VT1 Trang 12
Đồ án tốt nghiệp Đại Học Chương I: Tổng quan về hệ thống quang không dây
# N(-) •(- ,#~Q$"B/MZZ;T'4
S0(;@#'(3$
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(6&(-UZ/B/T4S0(;$X!.*
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U5$^Z="/43 ZU0./'5~
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Bảng 1. 3: Các phần tử khí có trong kênh truyền.
defegede h$&(T@M$%K>Z!
X-41+>(4'5)- /##4N4!;;/
L#0/'MZ)D
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*5&#(60/'0(;
0&*Z4('UH4N(r0+>$"
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SVTH: Trần Minh Phương – D08VT1 Trang 13
Đồ án tốt nghiệp Đại Học Chương I: Tổng quan về hệ thống quang không dây
Z0.T0=[(*(B/=(="0%=;
/0 =;(*$
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SVTH: Trần Minh Phương – D08VT1 Trang 14
Đồ án tốt nghiệp Đại Học Chương I: Tổng quan về hệ thống quang không dây
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SVTH: Trần Minh Phương – D08VT1 Trang 15
Đồ án tốt nghiệp Đại Học Chương I: Tổng quan về hệ thống quang không dây
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Bảng 1. 5: Điều kiện thời tiết và các giá trị tầm nhìn
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SVTH: Trần Minh Phương – D08VT1 Trang 16
Đồ án tốt nghiệp Đại Học Chương I: Tổng quan về hệ thống quang không dây
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=0="!*/U0*;/L)0+> /.+>$O
65(!="=.B(-=;U4H/=6/0)."#>
(-U!$
1.3.2. /o$&ZP$&?^
";/0="4!(r U(-=04T="P
#>$o6 ="(r(->#%H6B(-(r
Z="(r‚=3!+;)(6:
="P#>$D0H(6 k%;6(S(r
,# mP4U03&>)(S4
60=0S$
1.3.3. /o![MFVP
F-#%(5>U03.&4H/
=6;2/)#(6&(*(-4.#B$? Y6="V+>)04H/
=64N$OY>4-‚B(*-/';e
U4H/=6#(6=[=#$
1.3.4. p!&q$%&J=$%P&?!0!&>i&!r($&_s(TAO$%
o%wZ%3/0 3;\@(.4.#="
U $O"=" ;(/1>/=KL4H/
=62//06 'Y^$"CU0/'k
#S%B(-(;!65="Z$#="C

SVTH: Trần Minh Phương – D08VT1 Trang 17
Đồ án tốt nghiệp Đại Học Chương I: Tổng quan về hệ thống quang không dây
6(S•,##SQY(-(;>5"(#0
(*$F-:="Z%6)(S40!4N
/0(*(S:0k#$"#(-Uk-0Y
:.T(!&U3 P$
1.3.5. /o($!T_$@&TD"!
^Z="&U03=KL0
4H/=,Z 0 QB(-#)="##d ;((0
(*$?%3/.#(3 Zd)6•
H/.5#% YS//.04H/=6
$ƒ:'’=[>#Z>:#(-4H/=6/0U
=,$
x$c$ ?@\$%st$%@H(&)!&I$%-/.
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H#01L(>0#0>B/ >,#$
?665V4r+#00 
)6)0 !*/0/(7L Z10
# (4&Z- (L0/=‰6Z=K
L('3$I'!=KL('36#.0d~(
Lj-S#SM9(#B="/Q*/ Z k-
'3%%>(L =KL('3$I3
S(;/Q*/#=KL#0• "=(8
3 09#T#( j65(*=KL(53Pr4&
T>T(#>3T%=KL('3 Z>(L
0/$DU!~†{Z "=".L#3(-
%(*~xF4/=Zv)†o4/=$
73 U9V$:R(jO*=KL(5"/k3;0%
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#S4Ne$

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SVTH: Trần Minh Phương – D08VT1 Trang 18
Đồ án tốt nghiệp Đại Học Chương I: Tổng quan về hệ thống quang không dây
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#M$
SVTH: Trần Minh Phương – D08VT1 Trang 19
Đồ án tốt nghiệp Đại Học Chương II: Kỹ thuật OCDMA
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=KL=[(*;/-C(5B/ #> Y,
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#AB(B//,#4Z=6sEFG$DEFGH/
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>#>B/$

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(*=KL#3DEFG$D3Q)=M(7 :g-
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4Z=6)Q-H)5#Yv$x$DEFG65"
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#!.:10$?!H/#>":4.;
U)H65(*03DEFG!*/
#,, 3  DEFG !  */ #]#,,$D0 3
DEFG!*/=KL0;!*/U0=0(5C6/U
>4-/0 0/U>4-$D03DEFG
#>(ke=KL0+0="2/$D03DEFG
!*/=KL="6S6SU0=0(545VM1
#04axb 4a{b$>4-)(*0=KL0/'K0
0=64Y/M$D03DEFG#>65=KL0
7!*/#,/0pfE$

SVTH: Trần Minh Phương – D08VT1 Trang 20
Đồ án tốt nghiệp Đại Học Chương II: Kỹ thuật OCDMA
Hình 2. 1: Chia sẻ tài nguyên dựa trên kỹ thuật OCDM.
?!H/#>" #="04U0/M/0/C6
)654#>3DEFG8
 I3DEFGC6#)#(64#73
./r3 3C6/,#$
 I3DEFGC6#'=3)4#74ZC6//r
`f 3C64:(-/rfG$
 I3DEFGC6</=KL!*/0/M1C
6::$^LH656(*C6v]E4@0!*/
C6# 4Z=6)3DEFG.
J.4Z=6sIJ$?!C6,#(*!*/
Z 4Z=6=[6(*C6JJ4Z
=6$
?!H=d/+!/H,#=3*:))
4Z=6(*=KL)65(*03DEFG-
xEDEFG)03DEFGvEDEFG 3
DEFG4ˆEDEFG$?!="/"R(*( #C6)
65(>(*0343cEDEFG$
?!H/#>03DEFG,#=3*04Z=6
(*=KL(5C6)H65(*03DEFG(M
4Z=6 03DEFG(4Z=6$
DM #4-(70‚Y43xEDEFG (5
YC:3`,D#,=$
feged2 $![V@&)!&I$%.
X!H(5YU-3DEFG(*\#IY
v$v$~K4-/0(*!*/4@-4-!*/ /0(!;.0
4-4@-4-$F-=*(*=KL(5!3~//0
(!/ (*=‡%;.0Q$

SVTH: Trần Minh Phương – D08VT1 Trang 21
Đồ án tốt nghiệp Đại Học Chương II: Kỹ thuật OCDMA
Hình 2. 2: Sơ đồ khối của hệ thống OCDMA.
D04-C6 .CDEFG%/'\U-
3DEFG$O5"#(r%%Q":
DEFG)-C;(*0#PQ#-
>DEFG$D0C(*"\~-B/C+0(N) #(6)
Q0=KL0C0$#-3DEFG=KL
/M16(6]T]nnX,]X)%4axbU
Q(*C6-P0/M1 Z~CUQ
(6$F-P/4#70/axb /a{b)#(6/axbM1
Z-+(*/0()/a{bM1 Z6+$?!%
UQ4a{b6=[(*C6 6+
#(*/0($~04-/0=[(*B/*/ :Q-
=*Z/$
>/)-4-=;(*=KL(5//3
(!;.04-$>(' #P4-)#~4-/0#
3k6~04-/0#3$Z:
(*.C>4-.CDEFG$_-.C=KLQ-PC
3PC(C=KL(5C6T4-/0$=(*
.C=[(*(>!(N(5/L%N/axb a{b$
^/L%(*"-4-=#=0h$
o0Nh(*(S4@0N\=3UC)=3*/axb
#-~C$
fegef)!&I$%d0.
M(73U-3x]EDEFG(*\#Yv$ˆ$
>4-/0)(4Z=6~74&-(*(!4@
SVTH: Trần Minh Phương – D08VT1 Trang 22
Đồ án tốt nghiệp Đại Học Chương II: Kỹ thuật OCDMA
%N/(5>#X$D0X=(6(*C6T

-4-C6x]E4T-~C(*>#~>#Cx]E$#0YC
6)4a{b(r#4axb(*C6-P0
/$D0=(*C6=[(*r*/ Z~04-/0
0 Z/$
Hình 2. 3: Sơ đồ của một hệ thống 1-D OCDMA.
>4-)B(*4#7.~4-/0#3 
~%4-/0#3$?%#3
(*\V(B/FGi$4#7.FGi)Z
:)(*.C>4-.Cx]E$X(*(04-.Cx]
E)#3=[(*0>#)(7VM(3%0+=[
4N#>4e$~%=KL#3=[4N#>4e!0
+6V/Q*/$D‚%+FGi6V/Q
*/ Z4-.CZ.TZ$D0=(*.
C)#(64#7.#3 +FGi)=[(*5(r
(4T4-0`E$D3Q)%%N/(*/L7
4@-4-0=6h$
v$c y$%>^#$!I
#/'(70=[Z!#(5+"0C(M"
=KL0AB(7$D0AB(7# =KL0/</
#0(7#-%>(5+":0C(N‚
#/,==#,#0=KL$D0AB(76(3
>[ (M.M +"C"#Dj/
##D#,=$:)0(SMU0C(7Y
3UCD$?!!*/ ZDY0C(7x]E65
(*Q(5+"0C"#v]E Z0ZZM 
0(SM3$EZ>0/</#0(70)0C
(765(*/#>C(7!pDD)C(74B
uDD)C(74B4DDD)C(7/,4#IDDW$
“TM4.U +"0C(7=$O':)\
-=3:3p >#-60Py

i
j){”i”p]x){”j”p]x)=KL
SVTH: Trần Minh Phương – D08VT1 Trang 23
Đồ án tốt nghiệp Đại Học Chương II: Kỹ thuật OCDMA
/</#0(7:o#=op••{)x)v)W)p]x–$(6),#-B
#0#(6)0+>60P ##-60PN/ 
y
i
jM1 Z NU4xU/1jk(*\,U
~C1i$X-/</#0(70(*5)65(*
-C(70$D0/</(7(*=KL/r4!8
Phép toán đồng dư tuyến tính
y
i
j;a,b=•i.a.j+b– # p)v$x
T(6a b@=3$?!a•x b•{)665>#0P:3$
Phép toán đồng dư bậc hai
y
i
j;a,b,c=•i.a.j
v
+b.j+c–# p) v$v
T(6a,b,c@=3$Xa•b•xJv c•{)665>#0P:34Y
/M$
Phép toán đồng dư bậc ba
y
i
j;a,b=•i.j+a
ˆ
+b–# p) v$ˆ

T(6a b@=3$Xa•b•{)665>#0P(74B4$
Phép toán đồng dư hyperbolic
y
i
j=a.
i
j
+b #p) v$c
T(6 4@=3$X•x)665>#:0P(7/,4#$
i,j,a,b∈op••{)x)v)W)p]x–#c/MYT:$
fe{edey$%>^#$!I@EFG$
FC:3-C(7!:45$^+"C:
3=$O':)\=3:3/":o#=op)+"
-P:38

( )
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) )$$$) )$$$) ) {)x)$$$) x
i i i i j i p
S s s s s i p
−
= = −
v$†
T(6s
i,j
•i.j#p$s
i,j
)i j0!3:o#=o••{)x)W)p]x–$
(6) ZP:3


 0+>=8

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-C:3N/65(>(*=8
C
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,…,c
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v
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O-C \*CUC:3n=p
v
 w=p$_H/=6
4:"MZ; M<#Z;
x
a
p
λ
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 
v
c
λ
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30!3#-B/*/U`D|C|=p$,#(N•U
SVTH: Trần Minh Phương – D08VT1 Trang 24
Đồ án tốt nghiệp Đại Học Chương II: Kỹ thuật OCDMA
C  "  #  )  `D  '      -  C  D  Z  0    =3
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a c
n p p p
λ λ
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i
C:3C
i
(*‚
#4.v$x 4.v$v$
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Bảng 2. 1: Các chuỗi nguyên tố Si được xây dựng với p=5
DP:3
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FC:3D


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•{{{{{ x{{{{x{{{{x{{{{x{{{{x{{{{
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Bảng 2. 2: Các mã nguyên tố Ci được xây dựng với p=5
~4.)65;@P~C#-C:365(*
pB/# Z(-p#PB/#$D6+0-4axb#
PB/#  NU4axb(*+0(N4T/'#P
:3M1$—(5UC:3B#0>#CU6;
(M. *(56604H/=64:"MZ4@ Zp]x)
M<#U64@x =3/'KUC:3‚4@ Z
\* U 6$ IY v$c   v$†   L U C :3 Z  p
v
)p)p]
x)v•xx
v
)xx)x{)v)#;0(#U0MU6$
SVTH: Trần Minh Phương – D08VT1 Trang 25