Tải bản đầy đủ (.docx) (30 trang)

báo cáo bài tập lớn nghiên cứu ADPCm

Bạn đang xem bản rút gọn của tài liệu. Xem và tải ngay bản đầy đủ của tài liệu tại đây (883.05 KB, 30 trang )

GVHD Vũ Quỳnh
Nga
TRƯỜNG ĐẠI HỌC KỸ THUẬT HẬU CẦN CAND
KHOA ĐIỆN TỬ VIỄN THÔNG
BÁO CÁO ĐỀ TÀI BÀI TẬP LỚN
Tên đề tài:
NGHIÊN CỨU VÀ MÔ PHỎNG BẰNG MATLAB PHƯƠNG PHÁP
ĐIỀU CHẾ XUNG VI SAI THÍCH NGHI ADPCM
(ADAPTIVE DELTA PULSE CODE MODULATION)
Nhóm sinh viên : Chu Việt Thành
Hà Bế Mai Ly
Hoàng Minh Khánh
Lớp : B4-D1B
Giáo viên hướng dẫn : Thạc Sỹ Vũ Quỳnh Nga
Bắc Ninh – 2014
1 9/24/2014
GVHD Vũ Quỳnh
Nga
Nhận xét của giáo viên hướng dẫn





Bắc Ninh, Ngày Tháng Năm 20
Giáo Viên hướng dẫn
(Ký ghi rõ họ tên)
Nhận xét của giáo viên chấm







Bắc Ninh, Ngày Tháng Năm 20
Giáo Viên hướng dẫn
(Ký ghi rõ họ tên)
2 9/24/2014
GVHD Vũ Quỳnh
Nga
LỜI MỞ ĐẦU

  !"#$ %&
'()*+  ,- ./!/0
'12343!5 !6373( !82457(9!/
:;<=1>?;@6ABA!C?
1'5;</. /#<D1%,-
 .EE1;@DF 
?G!H1:'7D:E
EI 0+!@?;+ #0/
J:'7K<D1;@%B 0
 .;@L#GM6A
(2N2O'4L/. /PQ!3
/1/D6A,- .2457(;@L#'
5;</ 066L?GM66
.L?".;@D
/#RST='
Sinh viên thực hiện :

7 U#/
V/O?(N

V/(W
3 9/24/2014
GVHD Vũ Quỳnh
Nga
MỤC LỤC
4 9/24/2014
GVHD Vũ Quỳnh
Nga
DANH SÁCH HÌNH ẢNH
5 9/24/2014
GVHD Vũ Quỳnh
Nga
A, NỘI DUNG NGHIÊN CỨU
Chương I, Nghiên cứu tổng quan về các phương pháp điều chế
1, Phương pháp điều chế vi sai PCM
N;@A1N8!57(9X(+ T;<
/!/ =:Y6$Z[\J>
G+:'=!;@A1;<LTJ#
!0& ;"+  J  / !T]
R"!;@A1^'Z[\6_ :/
G;"!;@A'N;@A!!/:F =`^
!/D% /:,*
 :  /    /  !  ;@ *'  Z  ,
`:F =;@!!/I1;@6A
!J#  +TG '/G: =;@S!/
787366a3B9' V  +   b  ;@
* > G? #  !/ ! .8* c  Gd  (-9 / ! .
28*  c7  e 9'  7^  %  *  f  G  !;@  A
!8;.!;@A/gh63/
i631gh63>:!/jkhK9'7^C!/,J

;"Ti63!/K%J$9/B%j
6=,J;"Ti63/K%J$l
/B%jJ=,;"/!";H=
^0,j63,% '316
0G +;@S!/G 8ZG9'i63
631,J;"GM '[;.0G;"!;@A
/K" //K/^!"/c
jJLT%!;@A'
2, Phương pháp DM( Delta Modulation)
N/:;<% ?6L
+0!/J# ?1H1J%
 :/J# cH;"1=?
1LJ# H#/_!; 
,G#L/LTJ# 
6L6,/^?,#G# F D'
m;cT;<% ?43!!/_ %
R #$TJ# '4L/6L, T
J #   H    !% ,%   /   J ;@  J
# D   %  +  ;H  '  5;<    /
_  6A    g  G      1  J  #  6  ,  1
6 9/24/2014
GVHD Vũ Quỳnh
Nga
n!/G?J# Hog!/!"<K
<J# H'
3, Phương pháp DPCM(Difirential PCM)
p!/;<IL+ +d_ %
6L, TJ# H,% !//
og'W"4(_*gGD457(*[
G1G 6,/'70!;@% ?

,$"!;@G*J<+ 6"57('
4, ADPCM (Adaptive Difirential PCM)-G.726
N/;<c:T457('[;H&*
:6$G016L6,J# j
H,% ;G;"!;@A1;@% _
H, $; 1#% ?'U"
+ !/D$:G</0!;@J#
;<;<;H6A;<J:
TG;"!;@A;">TG+:J#
/'(J!/ =%!;@A*@"
%TJ# /'p;@S!/;<
23  57(8257(9'  J    G;"  !;@  A  1  
    D  ,  !;@  A  %  /  ,  % '  +
 b>G;"!;@AL/:6$$,+%
J# 1!+F ?G+:T1'71% G;"
JG;"!;@A';H1j, !/q33qP
257(/q33G,257('Dj, ;H %  L
+   J  !+  F   ? :  ,$8G!,9&
 ;@:Hd%!;@6LG?
>  /        ,'    r  S  !/  G!,
', q33G,#JG;"!;@A
;@L#+i ,1;@;/BA !C8&
 G;"!;@A;"19=,?F D!/
:G;"!;@A" ;@*6A!C[& ?
3's33qP3:?.,*J
G;"!;@A;@J+[& 
BA!C[& 1'[;.F =BA!CD"
G:  #    E  ,$    !#  !0  & '    ,  ,
q33G,1; !/0D" !;@A=
11JG;"!;@A/6AJ

G!,/]11L#`J'
Chương 2, Phần trọng tâm nghiên cứu:Phương pháp điều chế vi
sai thích ứng ADPCM(Adaptive Difirential PCM)
7 9/24/2014
GVHD Vũ Quỳnh
Nga
U":F =& +];@B;:
F =/)J$,+T`F 
=,>3H'[%  RJ# L
?!/,];L]'t =/;@#
F ;<6//L;<F >.3H
'7G:1#$57(/457(;@J
+<6cJ# /]/;@=1$"
 RJ# L]'[? G:!;@A% 57(;@6A
= G=T!;@AGMl;<
6)6 0!;@AGMu
j
agj'[? ;<6
>66$!;@A>GcJ# /L
]=;< r!/>G;"!;@A
u'p!/:;<:TG:
!;@A1LJ'O:!;@A1LJ
>G;"!;@AT1*@";<6TB 
!0& J# F '7 .;@%
?B 6,1J# ?1GM6A
G:!;@A1/G:LLJ1
#6$>1 ,=D$,+TJ# /'
V< %#6$L? /;.!/
6$G %/$:GG:L J#6$
+T1'

71!#$LJ'E0!/#$457(
1!;@ALJ8;HSd!/457(v2tO9'N
E,?@DG:!;@A1LJ/G:L
LJ'N/Sd!/457(v25Ov2tO'
8 9/24/2014
GVHD Vũ Quỳnh
Nga
2tsXEJ# ;@ %?G:1cB,
6AkvhG:B !00 +wG;"'7`
GD#wG;"cJGM3G;'p:
;@:18GMgh6
?19'x+  y& /z,!;@A1
z'LJ,$)LJ,={n!/wG;"
uT1>"i!i,$/,>6 $
H:,$T[& 'p;+<6c&
,!;@A'
2tOX%wG;"u;@];"1
TG:!;@A1'W1T'!;@
A!/D)JG6E/D)J<,
,JwTG;"'p!/#$ ?1R?/
1,,K0%%6L>'7#$2ts
rK,$#d%10 ^E/I
#$457(JE;H*
2tO+1!@ci,G/ 0
%wTG;"'V:TG:1457(v2tO
|j,Ga6;@0. %?1'W?F D!/
,$;#$57(}G6A;<!;@
A1!/_66"#$57(hG!;@A
1!'[? +  1:#$457(|j,Ga60
!;@=G:LLJ825O9D;/?

,?'
9 9/24/2014
GVHD Vũ Quỳnh
Nga
Hình 2.2 Sơ đồ nguyên lý xử lí tín hiệu vi sai thích nghi với đánh giá thuận và
đánh giá ngược mức tín hiệu vào
5;</L+J0>.T;<
6//L;<F ";<57(*G:
!;@A% 16 0!/u
j
agj;<2457(
/;<L ?J1 !/>u
rS!/;<*G:!;@A1LJ'
7 .;@#$% B 
6,1J# ?1GM6AG:!;@A
1/G:LJ16$>3 ,=
DJ$,+TJ# ?1'
 .;@B3B`;@=G/
;"'
2.1, Tổng quan:
O:11rG?>J# % ?B 57(
! .2) ~h• ,Ga6/J#    1$ :!/
•l|jj•jh,Ga6'
10 9/24/2014
GVHD Vũ Quỳnh
Nga

11 9/24/2014
GVHD Vũ Quỳnh
Nga

2.1.1, Mã hóa ADPCM
Z ,G?>J# /57(RJ# 
;@JGM`];"!;@TJ
# //J1'O:!;@AJE|gvgkv}v•6A
k•|)G;<ETJ#
;@ %?J '(:G:!;@A;@
J# 6!;@A1]& G/'J# ;"
!;@;@:/J# J# !;@A1/
RJ# '7DJ# R/J# 
!;@A1L#HG:K;<J
83391;"!;@J# //
//r!)'
[`2457(Gd "& #66";"J
T& ;"1'ZL,G#6 1;@=G/
G:1!C*",J;"G;"& #;"
J]!# ;@1T& ;"1'€"J
T& ;"1;@L#GcG:DGM
6A1!# T& ;"1'
V=j'kX(V12457( .
fG& •89;@66";"JT& •
;"18vg9'ZL,G#89*",J;"G;"ZZ
89;@=G/"!1'(1!# ,?F D
 fG " _ • NZO G ;@  6A     !;  ' 
12 9/24/2014
GVHD Vũ Quỳnh
Nga
O;",J;"ZZ89•89;@J]1
& •;"18vg9';<L;.;"JT
& ;"1I;@J GMD 
;@1T& ;"1's !!G:DI1)

G:12457('p% /DGDMG:D/
1!/RG:/,DAG0,‚G+'
2.1.2, Giải mã ADPCM
W$D10 ^$"R?TG:
1*",$G?>;@]57(R/57(
! .2)~h•,Ga6/,$% _1RG:,$
% _1RG:% _J!I`
B 0#,1RG:3'p% _57(J
6`!;@AG;"?3!/K0'
O:D,D;@=G:1/'O:
116L,G# ?J& #/L
,?& ;"1GM6A;"J,J;"G;"
& # ;@]& 1;"1'O:D
D!# 1/:6L,G#& #
/L,?& ;"1GM6A,J;"G;"
& # ;@]& ;"1:J
B*:16A1'ƒDT
& ;"1;@+/16L,G#T& 
#/L,?& ;"1 ;@Df
GT& #'
13 9/24/2014
GVHD Vũ Quỳnh
Nga

14 9/24/2014
GVHD Vũ Quỳnh
Nga
V=j'}XƒD2457( .

 [;#=2457(1& #N89

;@=G/G:D*",J;"G;"6689
;@J GM6A &  2457( ;"' ƒD D
6L,G##& •89/;"1& •8v
g9'p G:D6 1;@G>6 /& ;"
1 ;@fvGT#& •89'
2.2, Nguyên lý mã hóa ADPCM
2.2.1, Biến đổi định dạng đầu vào
W$/G?>J# 68,9! .2)~57(/J#
57(6!8,9R'
2.2.2, Tính toán tín hiệu vi sai
J# 68,9;@J]E8,9X
8,9„6!8,9…638,9
8jvg9
- J# R57(6!8,9
- J# ;"!;@638,9X
2.2.3, Bộ lượng tử tương thíchX
O:!;@AJE,RE|gvgk}v•6A
!;@AJ# 68,9"$:;<•l|j
j•gh,Ga6;<E'7 ,=!;@A8,9;@G?>L
+ .3363/Gc8,9;@
JGc,$;<J#6$'p)J /a 
+  b18n9TG:!;@A;GD
6 '
2.2.3.1, Tốc độ 40kbps
[G;@6A#E!;@8,9
8G$GG+:/:G0 9'[G!;@AJ†8,9
;<E"$:•l,Ga6{†8,9!0:|g‡3
†8,9;@;?,$!;@A1JE% ,?
1;<J/,$JE#6$G:!;@A1
!/#"kvG!8,91|j1'†8,9„lllll!/:

1 %? ,$/,6AG:D
E!/G;H %1!i'
15 9/24/2014
GVHD Vũ Quỳnh
Nga

O$G;@6A#E!;@8,98|
GG+:/:G0 9'[G!;@AJ†8,9;<
E"$:|j,Ga6{†8,9!0:|j‡3†8,9
;@;?,$!;@A1JE'p% ,?1
;<J/,$JE#6$G:!;@A1!/
#"•G†8,91|j1'†8,9„llll!/:1
 %? ,$/,6AG:DE
!/;H %1!i'
16 9/24/2014
GVHD Vũ Quỳnh
Nga
2.2.3.2, Tốc độ 60 kbps
VG;@6A#E!;@8,98gG
G+:/:G0 9'[G!;@AJ†8,9;<E
"$:gh,Ga6{†8,9;@;?,$!;@A1J
E'p% ,?1;<J/,$JE#6$
G:!;@A1!/#"•G!8,91|j1'
†8,9„lllll!/:1 %? ,$/
,6AG:DE!/;H %1!i'
2.2.4, Tương thích hệ spps phân thang bộ lượng tử
W$/J#6$8,9'• /!/kG•G|Gj
G !/†8,9/6$% ,?1JE!8,9'
[ +!JGD6AEG:!;@A1!/
?:X

- ["J# /1J# 61:>!"
89'
- ["J# /1J# 61:>K
86$!# 9'
ZL;<JTJ# ?1;@% ,Gc#6$
,?@.'
V#6$ 8,9;@J3r!)X
                            x 8,9„8gvj
vk
98,9oj
vk
ˆ‰†8,9Š
8jvj9
1 8,9;@",Dg'lh/gl'll
17 9/24/2014
GVHD Vũ Quỳnh
Nga
U"2457(•l,Ga6/Hˆ8†9;@n8
JB9;GD;"X
U"2457(j•,Ga6/Hˆ8†9;@n8
JB9X

U"2457(ghGa6/Hˆ8†9;@n8
JB9X
V#6$G?+.8G,19{
x!8,9„8gvj
vh
9!8,vg9oj
vh
 8,98jv|9

Z ,J;@#6$+1,?@X
x8,9„!8,9 8,vg9o8gv!8,99!8,vg98jv•9
1l!8,9g
2.2.5, Điều khiển tương thích tiếng nói
2!8,9!0 :,D‰lgŠJ# 11B
;"??gr!0l?  %6$!# +G
'[11 R$]T$:>J# 
'
18 9/24/2014
GVHD Vũ Quỳnh
Nga
V G=TG+:†8,9;@J;6 X
68,9„8gvj
vk
968,vg9oj
vk
s‰†8,9Š8jvk9
U/!„8gvj
v}
9!8,vg9oj
v}
s‰†8,9Š8jvh9
U"2457(|j,Ga6s‰†8,9Š;@nX
U"2457(j•,Ga6q‰†8,9Š;@nX
U"2457(gh,Ga6s‰†8,9Š;@nX

U=68,91!+#"s‰†8,9Š/s‰†8,9Š'
ZA G=8,9X

28,91B ;"??j? 668,9/!8,9

!/!"8†8,9>9/8,91B ;"??l6!/
K8†8,9!/M6$98,9I1B ;"??j,
,+i88,9|9)8,9„g;@)%g8,9„g'
8,vg9;@"Gc!8,93jv•X

ƒ",$BE/D;c?,cT
;H %?, #$T†8,9!/
M6$'p% /1B ;", %B /$
; >616P333G'
2.2.6, Bộ tính toán tín hiệu hồi phục và bộ phỏng đoán
tương thích
V/6<0TG:;<J=J# ;"!;@
638,9]J# 66$!;@AF8,9'ZA0 ^G:
19 9/24/2014
GVHD Vũ Quỳnh
Nga
K/ %3=h,
L'4*G:B :J# '
JJ# ;"!;@3EX

1X

J# R;@n;6 X

7G:6$G:K;@J/..'
- O:+G.X
1X

U/6‰lŠ„g]6‰8,v9Š„l_,8,v9„l/
„l{,>:Gd`X

‹
j
8,9‹l}k/‹
j
8,9‹gvj
v•
…
j
8,9? 

8,9„g=
g
8,9
„
j
8,9„l'
- U"G:+G.h{
-
G

8,9„8gvj
vf
9G

8,vg9oj
v}
6‰
F
8,9Š6‰
F

8,v9Š8jvf9

"„gjŒŒh
$:•l,Ga6G:+;<J;@>
D#6$r,8jvf9c/X
O8,9„8gvj
v•
9G8,vg9oj
v}
6‰
F
8,v9Š8jv•9
[? 

8,9„g=G
g
8,9„G
j
8,9„Œ''„G
h
8,9„l'
20 9/24/2014
GVHD Vũ Quỳnh
Nga
[? 6‰lŠ„g]6‰
F 
8,v9Š„l_,
F
8,v9„l
/„l

7^CG

8,9G"GG+j

3, Đánh giá phương pháp ADPCM
3.1, Ưu điểm
[;G?$:,C# )$:GTJ# TJ
# 57(R]fG/J# ?1;@!0
& "6$fWV‡GMh•,Ga6'[? 6$!;@GT]
Dr•;% ?B 68457(9=$:G
D/_GM|j,Ga6'71B ;"+  b1F $?
$:|j,Ga6$"J# ?1H6A
2457('U0%/;@D, ?ƒ'}jg
T771!+F ?% ?B 6LJ
|j,Ga6//!# ,'
2457(.!+>,J;"G;"!;@A1
?DG+  'Y!#`!+?fXg!/
1" ./"0!;@G/G  #H
/0!;@'7^66A:+
GD<DT ."_!#`jXgLT
^'W66"457("G/G T/
0!;@ G=/57(10/
0!;@G/G 2457(,y"!@?!/DG
)*G!; ,y"EE
+'H#Gc/0
%0F S/RHG&.
;@/)</Ž2457(c/:6L!LS
•/0!/$":E10!;@1
G>'7 .66,1;@6A
    )  `    !/ 57( 457( N57  /  (5|'

2457(;@6A:/#
'U†5I1!@?T,- ./'
3.2, Nhược điểm
Phương pháp ADPCM phức tạp hơn nhiều so với các phương pháp mã hóa
dạng sóng và nó chỉ có thể mã hóa được tiếng nói của con người. Mã hóa tham
số hoạt động ở tốc độ bit thấp ( xuống đến 2,4 Kbps) và mặc dù là tiếng nói
được tái tạo lại là hoàn toàn dễ hiểu nhưng chúng lại khác nhiều so với tiwwngs
nói tự nhiên.
21 9/24/2014
GVHD Vũ Quỳnh
Nga
B, PHẦN MÔ PHỎNG BẰNG MATLAB PHƯƠNG PHÁP ĐIỀU CHẾ VI
SAI ADPCM
Chương1, Tổng quan về mô phỏng ADPCM trong matlab

[1:GMJ6L,G#& 
!+?+  b% ?B 857(9/!iT
•+•& ?38]& ;"19
& .'(;H;@6A1!i
LG'72457(1;@6A*"4(83
46( !!3B9.G!; '56 
DJ12457(/6<R,$DF 6
=K!G'
1.1, Thuật toán mã hóa ADPCM
 .2457(;@6AL1;@D
JGMG;"6 '
g9N0& /fG'
j9?!.!T& L/_6$,J;"
G;"!;@A'
|9ZA=!+GD8ODjvg/ODjvj9=,J

;"G;""'
•9J6L,G#& L?/& L
'
k9!;@A16L,G#/2457(GR
DG0 '
h9(2457(L6L,G#GM6A,J
;"G;"JG;"|'
}9+& LGI/6L,G#LJ
L& '
f9W #& L",Dgj}?vgjf'
•9=_6$,J;"G;"!;@A"GM+
_6$;"/=!+GDL+2457('
gl9W #_6$,J;"G;"!;@A"
,Dlv|•'
gg9N; & /]_6$,J;"L"+
GD,??/.?3T!# '
gj9c%2457(•vG/?G;"g??& 
!# "'
1.2, ADCPM Thuật toán Giải mã
7 .D2457(1;@DJGM
G;"6 '
g9N0& /fG'
j9?!.!T& L/_6$,J;"
G;"!;@A'
22 9/24/2014
GVHD Vũ Quỳnh
Nga
|9ZA=!+GD8ODjvg/ODjvj9=,J
;"G;""'
•9(2457(L6L,G#GM6A,J

;"G;"JG;"|'
k9+& LGI/6L,G#LJ
L& '
h9W #& L",Dgj}?vgjf'
}9=_6$,J;"G;"!;@A"GM+
_6$;"/=!+GD'
f9W #_6$,J;"G;"!;@A"
,Dlv|•'
•9N; & /]_6$,J;"L"+
GD,??/.?3T!# '
gl9D!6$!;@,CfvG/?G;"g??& 
!# "'
1.3, Kết quả mô phỏng
/^60G R6
.!# .1/D.'I
 +."D/!# B3:
B0B_T!i'I1,y3Q!3P!/G3••g'P/
D.P06L,G#L6L%0!;@
'
1.3.1, Raw File
7.!# !/c:P'[;H1Y!#!0& Tf
(V‡G:6 fvG'[6$6 0
& "6$& '
23 9/24/2014
GVHD Vũ Quỳnh
Nga
V=kvgX\P'Ps!3
Hình 5-2: Zoomed Raw File
1.3.2, Tập tin mã hóa với thuật toán ADPCM
7 .2457(D! .;"11;@6A

1.?,#G'V=;"6
.1'41_1•G;@+  
!; )AGMS1'
24 9/24/2014
GVHD Vũ Quỳnh
Nga
V=k'|X2457(‘3Q!3
1.3.3, Giải mã tập tin bằng cách sử dụng thuật toán
ADPCM
[6$6 6& D'
V=k'•X433s!3
25 9/24/2014

×