Đồ Án Tốt Nghiệp 2014

5/21/2018 n Tt Nghi p 2014

1/41

Trang i

LI NI U

Trong x hi thng tin v truyn thng hin nay, cng vi spht trinmnh mca cc ngnh cng nghkhc v sbng nvkinh t l sphttrin khng ngng ca cng nghvin thng.Kthut vin thng hin nay ng

dng hu ht cc kt qunghin cu tch cc trc trong lnh vc vin thngv ngy cng hon thin hn, n gn nh ng dng hu ht cc c sl thuyt vthng tin s. Sha v truyn dn tn hiu dng sl mt phng php tng hiuqutruyn dn v gim thiu sai st thng tin do tc ng ca nhiu so vi thngtin tng t, ng thi ph hp vi cc hthng xl ngy nay ly c stc v hiu sut lm nn tng nn cc dliu dng sc sdng.

Trong cc phng php iu chschng ta phi nhc n phng phpiu chkha dch bin(ASK: Amplitude shift keying), n l mt phng phpc bn nht v n gin nht tin hnh iu chmt tn hiu. N l nn tngtrc tin cn nghin cu c thnghin cu thm cc hthng khc cao hn.ti l mt vn c trong vin thng c nhm ng dng vo vic truyn dliu thoi. ti nghin cu ng dng kthut ASK truyn dliu thoi.

Tnh hnh nghin cu trong v ngoi nc:Hin nay cng nghvin thng thgii t n mt trnh cao vi vickhng nhng truyn nhn tn hiu thoi m ngi ta c thtruyn cc tn hiu hnhnh, phim nh cng nh bt kmt dliu no m ngi ta c thsha vi tc

cc cao ln ti hng Mhz vi cng nghdi ng v ln ti hng Ghz nh cchthng truyn dn chnh nh viba s.Vic iu chtn hiu truyn i trong khng gian khng chn thun l iuchbin cxa m l cc hthng phc tp kt hp ciu chtn s, pha v

bin t c hiu qucao nht.Tuy nhin u l thnh qunghin cu ca cc nc pht trin, cn vi Vit

Nam cng nghdi ng vn chdng mc ng dng chcha t ti trnh cthnghin cu to ra mt cch thc, mt l thuyt mi hay xy dng mt hthngthng tin.

Do vy, vic nghin cu cc cch thc iu chc bn cng nhm lm tincho vic nghin cu tm hiu cc hthng phc tp hn, ng thi cng lcch ngi nghin cu c thny sinh t nhng tng mi.

5/21/2018 n Tt Nghi p 2014

2/41

Trang ii

LI CM N

Nhm thc hin ti xin gi n ton thqu thy c trng i Hc SPhm KThut Tp.HCM ni chung v qu thy c khoa in - in tni ring

li cm n chn thnh nht. Qu thy c truyn t cho nhm nhng kin thcchuyn ngnh cng nh nhiu kinh nghim qu bu l nhng hnh trang rt cnthit cho nhm bc ra trng v cng tc sau ny sau gn 5 nm gn b vitrng.

c bit nhm xin gi li cm n su sc n TS. V Minh Hun hngdn cho nhm rt tn tnh trong sut thi gian qua cng nhng li ng vin,khch lgip nhm vt qua thi im kh khn.Nhng ti liu bch cngnhng li gp qu bu gip nhm hon thnh n ny.

Cm n tt cbn b, nhng ngi ng gp kin v lun ng vin

gip nhm hon thnh n ny.Xin chn thnh cm n.

Nhm sinh vin thc hin

Trn Hi Sn Trn Nguyn Tr

5/21/2018 n Tt Nghi p 2014

3/41

Trang iii

MC LC

5/21/2018 n Tt Nghi p 2014

4/41

Trang iv

LIT K HNH

5/21/2018 n Tt Nghi p 2014

5/41

Trang v

LIT K TVIT TT

5/21/2018 n Tt Nghi p 2014

6/41

Trang vi

TM TT

Ni dung nghin cu:nghin cu cch thc truyn tn hiu v tuyn, nhm tin hnh nghin

cu struyn nhn tn hiu thoi vi hnh thc iu chn gin nht l iu ch

bin ASK. Nghin cu cch thc mt tn hiu ting ni c iu chv truyni trong khng gian, t gii iu chkhi phc li tn hiu ting ni truyn i v a ra loa.

ng thi vi vic nghin cu xy dng hthng truyn nhn trn, mcch ca vic nghin cu cng nhm kim chng cc c sl thuyt viu ch,m ha, thu pht, khuch i tn hiu t pht trin cc hthng tt hn vsau nu c c hi.

Cng vi cc mc ch nghin cu tm hiu kin thc l vic nhm thchin cng trnh nghin cu rn luyn knng nghin cu khoa hc, tch gpkinh nghim cho bn thn.Phng php nghin cu:

nghin cu mt vn khoa hc lun c nhng con ng khc nhautip cn vn . C thtin hnh nghin cu tchi tit n tng thnhcccng trnh nghin cu to ra sn phm thi cng, hoc cng c thtin hnh nghincu i tci tng quan n tng chim ring nh vi cc cng trnh nghin cul thuyt.

y, xy dng mch hon chnh, nhm tin hnh nghin cu hot

ng tng khi mt, kim tra vi tng khi ring lthy c hot ng cami khi, t kt hp cc khi v iu chnh ph hp xy dng nn mch snphm, tc l i tci chi tit n ci tng th. Lm nh vy chng ta c thddng kim hot ng ca mi khi v ddng khc phc nu xut hin li

Cthqu trnh nghin cu:

Giai on u nhm tp trung nghin cu hon thnh cc mch c bn c bit trong qu trnh thc tp c tnh cht n gin dthc hin.

Tip theo nhm tin hnh nghin cu thc hin vic iu chv gii iuchASK vi tn hiu mu ly tbto xung vung.

Sau khi kim tra chy n nh vic iu chASK, nhm tin hnh nghincu vic m ha v gii m PCM sdng IC TP3057.

Cui cng nhm tin hnh nghin cu v xy dng hthng thu pht tnhiu iu chqua Anten.

Giai on cui cng l hon thin mch v vit bo co khoa hc.

5/21/2018 n Tt Nghi p 2014

7/41

Trang vii

ABSTRACT

5/21/2018 n Tt Nghi p 2014

8/41

Trang 1

CHNG 1: GII THIU

CHNG 1: GII THIU

Nh gii thiu trn, cng nghnghin cu khoa hc ca nhm i vo nghincu xy dng mt hthng truyn nhn tn hiu da vo phng php iu chbin

ASK. Trc ht l thc hin iu ch, truyn v gii iu chmt tn hiu tto, tiptheo si tin hnh iu chtn hiu thoi (tn hiu ging ni) truyn i, cui cngl sthc hin truyn v v tuyn (khng dy).

Sau y chng ta stin hnh i tm hiu s lc viu chASK v vic truyntn hiu thng qua iu chASK v qu trnh thi cng mch.

1.1.S lc iu chASK:ASK (Ampitude Shift Keying) iu chkho dch bin : sng iu bin c

to ra bng cch thay i bin sng mang theo bin tn hiu tin tc

1.1.1. Nguyn l iu ch:Dng cc bit 0 v 1 thay i bin ca sng mang.

Sdng mt tn ssng mang duy nht.

Hnh 1.1:Nguyn l iu ch

5/21/2018 n Tt Nghi p 2014

9/41

Trang 2

CHNG 1: GII THIU

Hnh 1.2: Dng sng

1.1.2. Biu thc ton hc:Tn hiu sng mang:

Vc(t) = cost (1.1)

Tn hiu tin tc:

Vd (t) =

(1.2)

Tn hiu sau khi qua biu chASK:

VASK (t) = Vc (t).Vd(t)

=

(1.3)

Ta c: 2cosa.cosb = cos (a + b) + cos (a - b)

VASK (t) =

{( ) (

) [( ) ( )] } (1.4)

5/21/2018 n Tt Nghi p 2014

10/41

Trang 3

CHNG 1: GII THIU

1.2.Gii iu ch:C 2 phng php:

+Kt hp: mch phc tp nhng c khnng chng nhiu tt.

+Khng kt hp: mch n gin thng sdng trong mch tch sng hnhbao.

Hnh 1.3: S v dng song gii iu chASK

1.3.u im v nhc im: u im:+ n gin: Dng 2 bin khc nhau ca sng mang biu din 0 v 1,

sdng mt tn ssng mang duy nht.

+ Phng php ny chph hp trong truyn dliu tc thp ( 1200bpstrn knh truyn thoi )

Nhc im:+ Dbnh hng bi nhiu.

+ Khng ph hp i vi cc tn hiu c truyn trong cc knh truynyu cu tc cao.

5/21/2018 n Tt Nghi p 2014

11/41

Trang 4

CHNG 1: GII THIU

1.4.S khi truyn nhn tn hiu sdng iu chASK:

Hnh 1.4: S khi

Nguyn l:

+iu ch:

Tn hiu tin tc trc khi iu chc a qua blc thng thp loibcc nhiu tn scao.Sau tn hiu c iu chbin vi mt sng mangnhmt bnhn.Tn hiu sau khi iu chc cho qua mt blc thng di ly di thng ca ca tn hiu cn truyn i,tit kim bng thng.

+Gii iu ch:

Tn hiu iu chASK c a qua bnhn tch ly tn hiu cn thuv loi btn hiu sng mang. Sau tn hiu c cho qua blc thng thp

loi bton bthnh phn nhiu tn scao.

BPF

PSTNLPF

VASK(t)

Vd(t)Vd(t)(tin

tc)

Vc(t)

(sng mang)

Vc(t)

5/21/2018 n Tt Nghi p 2014

12/41

Trang 4

CHNG 2: HTHNG THU PHT TN HIU


2.1. S khi ca hthng :2.1.1. S khi pht:

Hnh 2.1: S khi pht

2.1.2. S khi thu:

Hnh 2.2: S khi thu

Khi nhn

tn hiu t

MIC

Khi iu

chPCM

Khi khuch

i cao tn

Khi iu

chASK

Khi to d

liu s

Khi to

dao ng

anten

Khi thu

anten

Khi khuch

i trung

tn

Khi gii

iu ch

ASK

Khi khuch

i m tn

Khi gii m

PCMloa

5/21/2018 n Tt Nghi p 2014

13/41

Trang 5


2.2. Thit kv xy dng mch in:m bo vic test mch c ddng nhm lm tng khi ring l

v sau khi hon thnh nhm sghp chng trn cng mt board mch.

2.2.1. Khi to dliu s:Khi ny c chc nng to dliu tn hiu iu chdng sd

dng cho vic kim tra cc khi pha sau trc khi thc hin iu ch tnhiu thoi truyn i.

Khi ssdng ngun dao ng tbdao ng bn bpht a

vo lm ngun xung tn hiu, sau tn hiu sa qua cc thanh ghi dch(IC 7495), tin hnh dch dliu nhcc Switch a ra dng dliu

smong mun.Dliu y l dng s8 bit vi cc bit c ththay i gitrl 0 hoc 1 ty thuc vo Switch.

Khi ny c thit kgm c 8 led n m tgi trbit tngng vi mi Switch, led sng tng ng vi bit c mc logic l 1 v

ngc li.

Mch dliu 8 bit sdng 2 IC dch 7495 mc ni tip to ra dliu 8 bit, vi d liu ng vo song song, d liu ng ra ni tip. D liu

ng vo c xc nh bng cch thay i cc switch tSW1 n SW8. IC7414 cng vi R, C to ra mch dao ng cung cp xung clock cho IC 7493

(IC m nhphn) m, 4 ng ra ca IC ny c ni n IC 7421 (IC cngAND), khi IC 7493 m 16 xung, ng ra ca cng AND ln 1, tc ng

ln chn s6 (chn mode) ca IC 7495, chn ny mc 1 sload dliu ng vo, nu mc 0 n sdch dliu. Ng ra QA ca IC 7493 c ni

n chn 8 v 9 (2 xung clock dch dliu ca IC 7495), khi chn s6 mc 0 th 2 xung clock ny tc ng dch dliu ra v dliu sny ldliu NRZ n cc, n sc ly ti NRZ data.

IC 7421: l IC gm 2 cng And 4 ng vo cu to nh hnh

di:

5/21/2018 n Tt Nghi p 2014

14/41

Trang 6


Hnh 2.3: S chn ca IC 7421

IC 7493: chc nng m thp, nhphn

Cu to n gin gm cc Flip Flop JK bntrong mc nh JK c ni mc cao do FFch c th hot ng trng thi lt. Trongmodul NRZ ny IC c thm c th chn12 ni chn 1 m nhphn 16 trng thi. Hnhdi sr hn

Bng 2.1: S chn v chc nng ca IC 7493

Hnh 2.4: S mch in bn trong IC 7493

5/21/2018 n Tt Nghi p 2014

15/41

Trang 7


Bng 2.2: Bng trng thi IC 7493

IC7495:y l thanh ghi 4 bit,IC c 3 chhot ng:

Ti song song. Dch phi khi cp xung (High to Low) vo chn 9 ng

thi chn 6 (Mode Control) mc thp.

Dch tri khi cp xung clock vo chn 8 ng thi ngthi chn 6 mc cao.

Pin 1:SER l chn dliu ng vo ni tipPin 2,3,4,5:l 4 ng data vo D1D4 tng ng vi ccPin 13,12,11,10: l dliu ng ra song song QAQDPin 6:Mode chn chPin 8, 9:2 chn cp xung clockPin 7:GND ni massPin 14:VCC ni ngun

Bng 2.3: S chn 7495

5/21/2018 n Tt Nghi p 2014

16/41

Trang 8


Bng 2.4: Bng trng thi ca IC 7495

Hnh 2.5:S mch in bn trong IC 7495

5/21/2018 n Tt Nghi p 2014

17/41

Trang 9


S nguyn l ca mch:

Hnh 2.6: S nguyn l khi to dliu s

Cc in trhn dng c gi trt330 - 1K, tng ng vi ngun VCCl

+5V, m bo cho led sng tt v khng bchy.

2.2.2. Khi nhn tn hiu tMIC:Sdng Transistor BJT, kt hp vi 1 Opamp khuch i bin

v iu chnh bin tn hiu nu cn.

Mch khuch i BJT c mc dng cu phn p vi cc E chung,ng ra tn hiu sc khuch i vdng v p

Opamp khuch i khng o,h s khuch i c th c iu

chnh nhbin tr10K,c gi trbin i t1 n 10 ln ty thuc vo gitrca bin tr.

Snguyn l ca mch:

U174LS95

SDI

1

A

2

B

3

C

4

D

5

MODE

6

CLK1

9

CLK2

8

QA

13

QB

12

QC

11

QD

10

U2

74LS95

SDI

1

A

2

B

3

C

4

D

5

MODE

6

CLK1

9

CLK2

8

QA

13

QB

12

QC

11

QD

10

D1

LED

D2

LED

D3

LED

D4

LED

J3

CON2

12 U4A

74HC21

14

52

6

D5

LED

D6

LED

D7

LED

D8

LED

MODE

VCC

BK

R1R

R2R

R3R

BK

R4R

R5R

R6R

R7R

R8R

CLK IN

U3

74LS93

CLKA14

CLKB

1 QA

12

QB

9

QC 8

QD 11

R012

R023

J1

NGUON

12

J2

WORD_8BIT

12

MODE

SW1

SW

SW2

SW

MODE

SW3

SW

SW4

SW

SW5

SW

SW6

SW

SW7

SW

SW8

SW

NRZ OUT

VCC

5/21/2018 n Tt Nghi p 2014

18/41

Trang 10


Hnh 2.7: S nguyn l khi nhn tn hiu tMIC

2.2.3. Khi m ha PCM:C nhiu gii php thc hin vic m ha PCM nh l:

- Thc hin m ha da trn cc IC sthng dng vi cc chc nng

c chia nhnh l ly mu, lng tv m ha, t gom li thnh mththng iu chPCM. Phng php ny dhiu v dthc hin, ddng

cho vic phn tch mch.Tuy nhin mch kh thi cng, phc tp tn nhiuIC, dbli v hot ng khng chnh xc nu thi cng khng ng.

- Phng php th 2 l s dng VK d thc hin cng vic mha. Phng php ny sn gin nu vic lp trnh tt, vic ng btnhiu cng tt hn do chly tmt ngun xung Thch anh duy nht. Tuynhin yu im ca phng php ny l VDK ch x l c tn hiu sdng nhphn m tn hiu thoi l tn hiu tng tnn ta khng thtrc

Q1BC 548B

C1

0.1u DC

C210uF 16V

C3

1uF 16V

R12k7

R2100k

R31k5

R433k

R5

470E

VCC 15V

J2THAY CON2 = BUS 2 CHAN

1

2

R6 POT

10K

-

+

U1

OP-07

3

26

7 1

4 8

R71K

VCC 15V

VCC -15V

J3

VCC 15V

123

VCC 15V

VCC -15V

IN

IN

U2

MICRO 3ly

GND1

LINE1

2

LINE2

3

U3

MICRO 6ly

GND

1

LINE-L

2

LINE-R

3

GND

4

LINE-L

5

LINE-R

6

IN

5/21/2018 n Tt Nghi p 2014

19/41

Trang 11


tip xl trn tn hiu thoi m phi qua khu chuyn i tn hiu tanalogsang digital trc khi m ha v thc hin qu trnh ngc li khi gii m.T ncng sto ra sai strong qu trnh chuyn i dliu dn nlm sai khc tn hiu gc.

- Phng php th3 l sdng IC TP3057/ TP3054 vi chc nng

c th l thc hin m ha PCM. Vi tn hiu u vo l tn hiu cn mha dng analog v d liu u ra l tn hiu c m ha PCM dng s. IC ny c th cho vic iu chdliu sdng trong truyn tnhiu thoi, rt tin dng. IC TP3057 c sn xut theo chun ca Bc M,

s dng xung clock lung 2,048Mhz m ha. Cn IC TP3054 th snxut theo chun ca Ty u, sdng xung clock lung 1,544Mhz mha.

Nhm nghin cu chn gii php sdng IC c th TP3057 thc hinm ha v gii m PCM.

S nguyn l mch:

Hnh 2.8: S nguyn l khi PCM

U1

TP3057

AGND2

DR6

DX11

-VCC1

+VCC4

VFRO3 GSX

14

TSX13

VFXI+ 16

VFXI-15

FSR5

BCLKR/CLKSEL7

MCLKR/PDN8

MCLKX9

BCLKX10

FSX12

C10.1uF

C20.1uF

+5V

-5V

+5V

R1 10k R2 10k

BCL 64KHZ

8KHZ

IN_ANALOG

OUT_PCM

MCL 2048MHZ

IN_ANALOG

OUT_PCM

BCL 64KHZ8KHZ

MCL 2048MHZ

J1

OUT PCM

1

J2

IN ANALOG

1

J3

HEADER 3

1

23

J4

VCC 5V

12

3

+5V

-5V

KHOI PCM SU DUNG TP3057

J5

MASS

1

5/21/2018 n Tt Nghi p 2014

20/41

Trang 12


Cc tC1 v C2 lm nhim vlc ngun cho IC

- Cc trR1 v R2 l trto hskhuch i cho bkhuch i uvo ca IC TP3057.

- Tn hiu analog cn iu cha vo chn 16.

- Tn hiu sPCM ra chn 11.

- Chn s9 l chn cp xung clock master cho IC hot ng.

- Cc chn FSX v FSR l chn nhn xung ng bkhung cho vicm ha v gii m.

- Chn VFRO l chn dliu analog ng ra khi thc hin gii m

PCM.- Chn DR l chn dliu PCM ng vo cn gii m khi phc

tn hiu gc.

- Chn s7 BCLKR/CLKSEL c chc nng nh bng sau:

TABLE Selection of Master Clock Frequencies

BCLKR/CLKSEL

Master Clock

Frequency Selected

TP3057 TP3054

Clocked 2,048Mhz1,536Mhz

or1,544Mhz

01,536Mhz

or1,544Mhz

2,048Mhz

1 2,048Mhz1,536Mhz

or

1,544Mhz

Bng 2.5: La chn tn s

5/21/2018 n Tt Nghi p 2014

21/41

Trang 13


- Chn s8 l chn nhn xung master clock cho vic gii iu chkhi tn hiu vo chn ny l xung, nu c c kt ni ln mc "1"lin tc th power down thit b, khi kt ni lin tc ln mc xungmc "0" th n sly xung master clock bn pht lm master

clock cho bn nhn.

Mt IC TP3057 c thng thi thc hin cng vic m ha v giim PCM bi v hai khi ny c thit kring ltrong cng mtIC, khng nh hng g n nhau.

2.2.4. Khi to dao ng:to ra ngun dao ng n nh cung cp cho cc khi trong h

thng, nhm thc hin chn phng n dng mch dao ng Thch anh.

Tinh ththch anh to ra dao ng vi n nh cao v t bnh hngbi yu tbn ngoi.

Mch dao ng gm mt tinh ththch anh 4Mhz kt hp vi cccng o v cc t, in trto ra xung clock cnh c tn s4Mhz.

Ngun xung clock ny sc cho qua IC chia tn CD4040 m ly cctn sng ra mong mun.

Ng ra chn s9 l xung clock tn s2,048Mhz lm xung master

clock cho PCM, cc ng ra chn s2 (64Khz) l xung bit clock v chn s12 (8Khz) l xung FSX cung cp cho PCM.

Ng ra chn s6 l xung tn s512Khz sc a n mch lcPI to ra dng sng sin lm sng mang iu chcho mch iu ch

ASK.

Mch lc PI gm 2 loi linh kin thng l tv cun cm nhmhiu chnh xung vung thnh dng sng sin ddng cho vic iu ch

ASK.

S nguyn l mch:

5/21/2018 n Tt Nghi p 2014

22/41

Trang 14


Hnh 2.9: S nguyn l khi to dao ng

2.2.5. Khi iu chASK:iu chASK l nhm bin i bin ca tn hiu sng mang theo

dng ca tn hiu tin tc. iu m ta mong mun chnh l truyn tn hiu tintc i xa (c dy hoc khng dy). Tuy nhin vi cc tn hiu nm dy

tn sm thanh (tn hiu thoi) th c tn sthp (300Hz - 3,4Khz) cho nnkhng ththc hin vic truyn i xa v tn hiu sbnh hng bi v s

cc loi nhiu cng tp m. Do vy chng ta cn phi nhn mt sng ctn scao vt ra khi di tn sm thanh mang tin tc i. Vic ghp

tn hiu sng mang v tin tc c gi l iu ch. C nhiu loi iu ch

khc nhau nh iu chbin , iu chtn s, iu pha, Tuy nhin y ta chxt phng php iu chn gin v dthc hin nht l iu

bin.

C nhiu cch iu chbin khc nhau nh sdng transistor, sdng IC chuyn dng. y, ddng thc hin v m bo n nh,

5/21/2018 n Tt Nghi p 2014

23/41

Trang 15


nhm nghin cu chn gii php sdng IC iu chchuyn dng lIC1496.

S chn IC1496

Hnh 2.10: S chn ca IC 1496o Chn 1, 4: tn hiu ng vo tin tc.o Chn 2, 3: hiu chnh khuch i.o Chn 5: Bias.o Chn 6, 12: ng ra.o Chn 8, 10: ng vo sng mang.

Hnh 2.11: S khi MC1496

5/21/2018 n Tt Nghi p 2014

24/41

Trang 16


S nguyn l mch:

Hnh 2.12: S khi iu chASK

Mch bao gm mt bkhuch i vi sai 4 transistor trn da trnbkhuch i vi sai tiu chun vi ngun dng i. Cc thu ng ra c

ghp cho m dng sng y c cn bng khi php nhn ca 2 tnhiu in p xy ra. l tn hiu ng ra l mt thi hng ca php nhn 2tn hiu ng vo.

Cc transistor v in tr, tin mc thm bn ngoi l nhm

iu chnh dng sng iu chcng nh hsiu ch.

IC 1496 c dng nh l biu chcn bng. Tn hiu NRZiu chth c kt ni ti chn 1 qua transistor m BC548B.

IC ny c hai ng ra lm vic nh biu chcn bng. Ng rathhai c thc kt ni vi chn 4 qua transistor m BC548B.

DIEU CHE CAN BANG

R11

1K

R12

10K

+5V

-5V

R13470

R14

330K

R154K7

R16

470

R1710K

C20.47uF

C3101

+15V R18

2K

OUTPUT

R19

470

R20

4K7

R21

470

R22470

R232K2

R241K

-15V

J8

DATA_IN

12

DATA

J9

CARRIER_IN

12

DATA

CARRIER

J10

VCC 5V

123

+5V

-5V

CARRIER

U1

MC1496

CIN+8

CIN-10

SIGIN+1

SIGIN-4

GADJ

2

GADJ

3

OUT+ 6

OUT- 12

VEE

14

BIAS

5

Q1

BC548

Q2

BC548

Q3

BC548Q4

BC548

Q5

BC558

Q6

BC558

R1

10KR2

5K1

R3

1K

R4

6K8

R5

10K

R6

10K

R75K1

R8470

R9470

R10

1K

R2810K

+15V

+15V

+15V

-15V

+15V

C1

0.47uF

J3

VCC15v

12

J4

OUTPUT

12

-15V

+15V

OUTPUT

-15V

-15V

5/21/2018 n Tt Nghi p 2014

25/41

Trang 17


Tn hiu sng mang m tn th c kt ni ti chn 8 qua tghp tbdao ng sng mang m tn.

Nhng ng ra c iu chc c chn 12 v 6 ca IC ny,sau c khuch i cn bng bi cp transistor BC548B v BC

558B.Ng ra iu chcn bng cui cng c xc nh ti ng ra.

Bin tr10K c sng mang cn bng trong khi bin tr1 K thc tn hiu m tn ng vo cn bng.

t trc ng ra 100K iu chnh mc 0 DC ng ra. Bin trng ra 2K thay i mc (bc) ca tn hiu iu chASK.

-5 n +5V DC c xc nh bi ng ra th2 ca biu chcn bng a vo sng mang ng ra ASK.

2.2.6. Khi khuch i cao tn:Tn hiu sau khi iu chc tn sca sng mang c thtruyn

c trn knh truyn khng dy. Tuy nhin cng tn hiu th cha v n sbsuy hao gn nh hon ton nu nh khong cch xa v vic khi

phc l srt kh khn. Do vy, ta phi tin hnh khuch i cng sut pht

i tn hiu pht i c cng sut ln truyn i xa v bn nhn c ththu v gii iu chtn hiu .

Bkhuch i n gin l dng transistor khuch i cng sut. Phichn loi p ng tt tn scao v cng sut ln.

Cc transistor mc dng phn cc, c 2 tng khuch i: mt tngmc dng C chung khuch i dng, mt tng mc dng E chung khuchi cdng v p.

Tn hiu sau khuch i ln b trsuy hao qua knh truyn.

S nguyn l mch:

5/21/2018 n Tt Nghi p 2014

26/41

Trang 18


Hnh 2.13: S khi mch khuch i cao tn

2.2.7. Khi thu, khi khuch i cao tn v khuch i trung tn:Mch vo anten bao gm cc linh kin thng l in cm v t

in hot ng trn nguyn tc mch cng hng tn s, mch vo sto ra

tn sdao ng ni chnh l tn sca tn hiu pht. Khi , u vo b

thu, tn hiu pht c cng tn svi tn sdao ng ni sc thu vo.Trn y l dng gin lc ca mch thu i tn, tn spht l cnh nnmch thu sdng tn scnh cho n gin.

Mch tin khuch i: L khuch i thu c, bi v tn hiu thu

c c cng rt thp, khng tha i gii iu chc. V vy, tastin hnh khuch i mc tn hiu ln mt mc ng k.

Mch khuch i trung tn: Tip tc khuch i tn hiu thu c v

iu chnh li ca mch. Vi mt smch ta c thsdng nhiu lpkhuch i trung tn khuch i tn hiu, nhng y, ta thc hintruyn nhn gn nn chcn sdng mt tng khuch i khuch i tn

hiu trc khi a i gii iu ch.

J4

CON1

1

R34

5K6

R35

1K

An

ten

KHOI KHUECH DAI CONG SUAT+15V

J1

Power

12

+15V

C410n DC

C5

0.1 DC

C6

0.1 DC C7

0.1 DC

R26

10k

R27

4k7

R28

100E

R29

100K

R30

18K

R31

100E

R32

100E

Q11BC547

Q12BC547

R33

10k

J2

CON2

12

IP

IP

5/21/2018 n Tt Nghi p 2014

27/41

Trang 19


S nguyn l mch:

Hnh 2.14: S khi mch thu

2.2.8. Khi gii iu chASK:Vic gii iu chy sdng mch tch sng hnh bao sdng

Diode, kt hp tv diode thc hin lc btn hiu sng mang tn scao,gili dng bin ca tn hiu chnh l tn hiu tin tc cn ly.

Sau khi lc ly tn hiu tn sthp th ta stin hnh a tn hiu qua mch quyt nh ly li dng sng vung ca tn hiu PCM.

Sng vung ny chnh l tn hiu tin tc c m ha PCM.Tn hiu ny sc a n mch gii m PCM khi phc tn

hiu tin tc gc (tn hiu thoi)

S nguyn l ca mch:

U1

Bien_ap_doi

11

22

3 3

4 4

J1Antenna

1

CghCAP NP

VC

CAP NPR1390K

R3

150E

R41K

Q1ABC548

1

3

2

+5V

J3

VCC 5V

12

C1

103

Q2A

1

3

2

U2

Loi_trung_tan

A11

A22

A33

B1 4

B2 5

R2100E

+5V

C24,47n

C5C182n7 st

C647n

J2

OUT TO DEMOD

1

MACH VAO ANTEN MACH

KHUECH

DAI TRUNG

TAN

MACH TIEN

KHUECH DAI

+5V

5/21/2018 n Tt Nghi p 2014

28/41

Trang 20


Hnh 2.15: S khi gii iu chASK

2.2.9. Khi gii m PCM:Chn gin sdng cc chn ng ra ca phn gii m PCM ca IC

TP3057.

S mch cng tng tbn mch m ha.

S khi ca mch:

D1

4148C1102

R110k

R210K

U1

LM311

IN +2

IN -3

GND

1

VCC

-

4

B

5

O/B

6

OUT7

VCC

+

8

J1

IN

1

2

J2

OUT

1

2

R32K2

R4

10K

U2A

7404

1 2

VCC +15V

VCC +15V

VCC -15V

VCC -15V

VCC

J3

VCC5V

12

VCC

J5

VCC 15V

12

VCC +15V

VCC -15V

5/21/2018 n Tt Nghi p 2014

29/41

Trang 21


Hnh 2.16: S khi mch gii m PCM

2.2.10.Mch khuch i cng sut m tn:Mch khuch i tn hiu m tn sdng IC TDA2003, khuch i

cng sut ca tn hiu thoi a ra loa.

Mch ng dng ny ly tdatasheet do nh sn xut cung cp.

Mch c thkhuch i cng sut n 6W.

S khi ca mch:

U1

TP3057

AGND2

DR6

DX 11

-VCC1

+VCC4

VFRO3 GSX

14

TSX 13

VFXI+ 16

VFXI- 15

FSR5

BCLKR/CLKSEL7

MCLKR/PDN8

MCLKX 9

BCLKX 10

FSX 12

C10.1uF

C20.1uF

+5V

-5V

R1 10k R2 10k

BCL 64KHZ

8KHZ

OUT_ANALOG

MCL 2048MHZ

IN_PCM

OUT_AN

ALOG

BCL 64KHZ8KHZ

MCL 2048MHZ

J1

OUT PCM

1

J2

IN ANALOG

1

J3

HEADER 3

1

23

J4

VCC 5V

12

3

+5V

-5V

KHOI PCM SU DUNG TP3057

J5

MASS

1

IN_PCM

5/21/2018 n Tt Nghi p 2014

30/41

Trang 22


Hnh 2.17: S khi mch khuch i cng sut m tn

U3

TDA2003

IN+1

IN-2

GND

3

OUT 4V

CC

5C1

10uF

C2100uF

C3

470uF

C4

1000uF

C5100nF

C6100nF

Cx1/2piBR1 = 39nF

R1220E

R22R2

R31

RX20xR2 = 39E

J1

THAY CON2 = BUS 2 CHAN

1

2

J2

1

2

VCC 12v

J3

12

3

J4

VCC 12V

12

VCC 12v

5/21/2018 n Tt Nghi p 2014

31/41

Trang 18

CHNG 3: GII THIU PHN MM VMCH V M PHNG PROTEUS

CHNG 3: GII THIU PHN MM VMCH V M PHNGPROTEUS

3.1. Gii thiu phn mm:Proteus l phn mm htrthit kv m phng cc loi mch in t. So

vi cc phn mm htrm phng cc mch in khc nh:

Circuitmaker 2000 ngoi vic htrthit kmch in th phn mmcn cho php vv m phng mch schun xc ti 95% nhng li

bhn chkhi m phng cc loi mch tng tcng nh tng hpcsv tng t.

Workbench phn mm ny c th linh kin phong ph v c nhiuthit bo kim tra nh thc tgip ngi thit kddng quan stcn chnh thng sca mch in. So vi cc phn mm khc th

Workbench cho php m phng cc loi mch in (csv tngt).

Orcad, Eagle v Protel l cc phn mm htrv vs nguynl v s mch in nhng khng htrm phng mch nguyn l.

Proteus c thmnh hn hn vcc mt:

Th vin linh kin phong ph. Htrnhiu thit bo kim tra. Cho php thit kv chy m phng s nguyn l gm cc mch

tng t, mch s, mch tng hp csv tng t Cho php chy m phng cc loi vi iu khin, EPPROM, PIC Htrthit kmch in.

3.2. Hng dn sdng phn mm Proteus:3.2.1. Khi ng chng trnh:

Sau khi ci t Proteus, vo Start menu, khi ng isis ca Proteus:

5/21/2018 n Tt Nghi p 2014

32/41

Trang 19


Hnh 3.1 Vo giao din mProteus

3.2.2. Giao din chnh:

Hnh 3.2: Giao din chnh

5/21/2018 n Tt Nghi p 2014

33/41

Trang 20


3.2.3. Cc toolbar chnh:Thanh s1:

-Cm 1: to nhanh mt trang thit k, m trang thit k to,lu trangthit k

-Cm 2: In ctrang,chn vng ib ty -Cm 3: Chia li im trang thit k.-Cm 4: Zoom linh kin v gia trang,phng to,thu nh, fix trang,zoom

vng tuchn.-Cm 5: Ct, coppy, paste trang.-Cm 6: Copy, move, quay, xo linh kin trn trang.

-Cm 7: Chvng biu tng u,chn linh kin.

Thanh s2:

1. Cho php chn linh kin sau khi nhn nt P hp thoi DEVICES.2. Chm im trn trang.

3. To nhn:nhn tri chut ln dy dn v t tn.4. Text: nhn tri chut v v.5. To Bus6. Khng sdng7. Nhn tri ln linh kin xem edit component.8. Ngun, t, bus9. Chn linh kin.10. Simulation Graph.11. Tape recorder.

12. Generator: DC, xung, sin, 13. Voltage Probe: ging vn kthng nhng chc mt u dy, hin strc tip.14. Current Probe: ging ampe knhng chc mt u.15. Dng co: oscilloscope.vn kAC, DC, ampe kAC, DC16. Vng 2D.

5/21/2018 n Tt Nghi p 2014

34/41

Trang 21


17. Vhp 2D.18. Vng trn 2D19. Vcung trn 2D20. Va gic 2D

21. Text 2D: nhn tri vo trang va type.

Thanh s3:

Quay tri, phi, i xng chn ngang dc linh kin trnhp hin thlinh kin.

Thanh s4:

iu khin Start, step by step, pause, stop qu trnhm phng.

3.2.4. Thit kmch m phng:

Hnh 3.3: Mch m phngu tin ta ly tt c cc linh kin cn dng ra hp thoi

DEVICES bng cch nhn vo chP hp thoi DEVICES, ta schp thoi Pick Devices hin ra nh sau:

5/21/2018 n Tt Nghi p 2014

35/41

Trang 22


Hnh 3.4: Giao din hp thoi Pick Devices

G tn linh kin cn ly vo Keywords.

Hnh 3.5: Giao din Keywords

Hnh linh kin v s chn mch in shin ra bn cch khi ta nhnvo chn linh kin. chn ta nhn OK lc ny trn hp thoi DEVICES

sxut hin tn linh kin chn.

ly linh kin cn thit k ta nhn vo tn linh kin trong hp

thoi DEVICES, dng thanh cng c thay i cho phhp sau sang nhn tri vo trang thit kt linh kin.

5/21/2018 n Tt Nghi p 2014

36/41

Trang 23


Ta ln lt a cc linh kin cn dng ra trang thit k. Ngun v

t ly ra bng cch nhn vo biu tng trn thanh cng cs2, ta spxp cc linh kin theo mch nguyn l.

i dy ta nhn vo chn linh kin thnht, di chuyn chut vnhn vo chn linh kin th2. sa mt linh kin ta nhn p chut lnlinh kin .

Nh vy ta m phng xong mch hon chnh. chy mch tanhn vo nt Start trn thanh cng cs4.

3.2.5. Kt qum phng c ca mt smch trn Proteus:3.2.5.1. Mch m phng khuch i cng sut m tn:

Hnh 3.6: M phng mch khuch i cng sut m tn

trn Proteus

5/21/2018 n Tt Nghi p 2014

37/41

Trang 24


Hnh 3.7: Dng sng tn hiu ng vo v ng ra ca

mch khuch i cng sut m tn

Tn hiu ng vo c bin 1V v tn s1Hz.

Tn hiu ng ra c khuch i ln v c bin l 5V gp 5 ln so vi

bin ca tn hiu ng vo.

5/21/2018 n Tt Nghi p 2014

38/41

Trang 25


3.2.5.2. M phng khi thu:

Hnh 3.8: M phng khi thu trn Proteus

Hnh 3.9: Dng sng ca tn hiu ng vo v ng ra ca

mch thu

5/21/2018 n Tt Nghi p 2014

39/41

Trang 26


Nhbthu thu c tn hiu iu chASK c khuch i avo bgii iu chkhi phc li tn hiu ban u.

3.2.5.3. M phng mch iu chASK:Do qu trnh m phng ASK trn Proteus gp kh khn nnnhm tin hnh m phng ASK trn Matlab phn mm m

phng mch c hc trong chng trnh o to khi vinthng.

Tn hiu tin tc c biu thc:

[() ()] (3.1)Tn hiu sng mang c biu thc:

x=Asin(2F1t) (3.2)

Tn hiu ASK:

v=x.*u (3.3)M phng trn M file:

clear all;clc;close all;F1=input('Enter the frequency of carrier=');F2=input('Enter the frequency of pulse=');A=3;%Amplitudet=0:0.001:1;

x=A.*sin(2*pi*F1*t);%Carrier Sine waveu=A/2.*square(2*pi*F2*t)+(A/2);%Square wave messagev=x.*u;subplot(3,1,1);

plot(t,x);xlabel('Time');ylabel('Amplitude');title('Carrier');grid on;subplot(3,1,2);

plot(t,u);xlabel('Time');ylabel('Amplitude');title('Square Pulses');grid on;subplot(3,1,3);

plot(t,v);xlabel('Time');

5/21/2018 n Tt Nghi p 2014

40/41

Trang 27


ylabel('Amplitude');title('ASK Signal');grid on;

Hnh 3.10: Dng sng m phng tn hiu ASK trn Matlab

Tn hiu sng mang c bin 3V, tn s30Hz.

Tn hiu tin tc c bin 1.5V, tn s5Hz.

Tn hiu ASK c bin thay i theo tn hiu tin tc. y l trng hpc bit ca ASK gi l OOK(on off keying).

Khi V(t)=+1.5V th V(ASK)=3V

V(t)=-1.5V th V(ASK)=0V

Trong :

V(t) l bin ca tn hiu tin tc.

V(ASK) l bin ca tn hiu ASK.

5/21/2018 n Tt Nghi p 2014

41/41

Trang 28


Documents

Đồ Án Tốt Nghiệp 2014