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N 2ACHUYN NGNH IN T VIN THNG GVHD: ThS. Nguyn Vn AnSVTH : MSSVTrn Vn Thnh 10053181Nguyn Ch Th 10078501MCH IU KHIN THIT B BNG SNG RF TI:TRNG I HC CNG NGHIP TP.HCMKHOA CNG NGH IN TB MN IN T - VIN THNG

Thnh ph H Ch Minh, thng 4 nm 2014NI DUNG 1. Gii thiu tng quan v sng v tuyn2. Thit k v thi cng h thng3. Kt lun

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1. Gii thiu tng quan v sng v tuyn

Khi nim sng v tuyn (RF)- Sng v tuyn ( Radio Frequency )l mt kiubc x in tvibc sng trongph in t di hn nh sng hng ngoi. Sng v tuyn c tn s t 3KHz ti 300GHz, tng ng bc sng t 100km ti 1mm.- Cc tn s khc nhau ca sng v tuyn c c tnh truyn lan khc nhau trong kh quyn tri t. Sng di truyn theo ng cong ca tri t, sng ngn nh phn x t tng in ly nn c th truyn rt xa, cc bc sng ngn hn b phn x yu hn v truyn trn ng nhn thng.Loi sngTn sBc sngSng di v cc diSng trungSng ngnSng cc ngn3-300 KHz0,3-3 MHz3-30 MHz30-3000 MHz100Km - 1Km1000m - 100 m100m - 10 m10m - 0,01 m2.THIT K V THI CNG MCH2.1. S khi2.2. Khi ngun2.3. S mch pht sng v tuyn2.4. Module pht RF 315MHz 2.5. Tnh ton khi pht2.6. S mch thu v tuyn2.7. Tnh ton khi thu2.8. Khi iu khin2.9 .Khi Relay cng sut2.10.Chn Relay2.11. Tnh ton chn BJT v cc in tr phn cc 2.12 . Nguyn l hot ng ca ton mch

2.THIT K V THI CNG MCH 2.1 S khi

2.2 KHI NGUN

2.3 S mch pht sng v tuyn

2.4 Module pht RF 315MHz

Mch pht c mc theo kiu khuch i E chung. Cryst1 l thch anh to dao ng, tn s 315Mhz, khi c cp in n t dao ng to ra sng hnh sin. Transistor S9018 l transistor khuch i cao tn, khuch i tn hiu t thch anh v tn hiu u ra ly chn C ca transistor. R2 l in tr to in p chun cho thch anh, R3 nh dng cho chn E ca transistor.

2.5 Tnh ton khi phtin p : DC 3 ~ 5V Dng in 3 mA (DC 5V) Cng sut pht 10mW Tn s hot ng f = 315MhzCng sut my pht (cng sut c ch) : Pi = 10mWCng sut tiu th: P0 = U.I = 5.3.10-3 = 15mWHiu sut my pht: H = (Pi/P0) = 67%

Bc sng :

Chn anten c di bng 1/4 bc sng l 0,23m (23cm)

2.5 S mch thu v tuyn

2.6 S Nguyn L Khi Thu Sng RF

2.7 Tnh ton khi thuModule thu RF 315Mhz: Hot ng in p: DC 3 ~ 5V. Dng in 3 mA (DC 5V). Hot ng tn s: 315Mhz nhy: -105 dBm nhy my thu l kh nng thu c tn hiu nh nht u vo m my thu cho ra c mc tn hiu b ch th bnh thng. Phm vi thu 100m i vi khng gian m. Anten s dng l loi anten rt, di 23cm.

2.8 Khi iu khin v hin th

2.9 Khi Relay cng sut

Khi cng sut gm : Relay 5VDC, BJT C1815 khuch i dng qua Relay. Relay l mt cng tc iu khin t xa n gin, n dng mt dng nh iu khin mt dng ln v vy n c dng bo v cng tc nn cng c xem l mt thit b bo v. Kt cu Relay gm c mt li st, mt cun t v mt tip im.Chn Relay 5V:+ in p tc ng : 5VDC+ in tr cun dy Relay : 167 (ohm)+ Dng in qua cun dy khong : 30 mA+ in p ng m : 220V+ Dng qua tip im : 7A

2.10 Chn Relay2.11 Tnh ton chn BJT v cc in tr phn cc

Chn BJT C1815, BJT lm vic ch bo ha.

Dng in qua cun dy ca Relay:

Dng in qua Relay cng l dng in qua cc C ca BJT, suy ra : Ic = 28.7 (mA) Transistor dn bo ha th : Chn Ib = 10x0.4 =4 (mA)Tc dng ca Diode : dng trnh dng Fuco Trong cun dy sinh ra trong qu trnh hot ng lm hng BJT Vic chn loi Diode khng kh khn ch l loi Diode chu c dng tng i nh. Trong mch ny ta chn Diode l loi 1N4148.

2.12 Nguyn l hot ng ca ton mch Mch PT 2272 M4 l b gii m iu khin t xa dng chung vi PT 2262 s dng cng ngh CMOS . C 8 a ch m ha, 4 chn d liu chnh v th c nhiu cch set chn 3^8 cch , c th sn xut nhiu m khng s set trng m . mch thu PT 2272 set chn( 1 -> 8) nh th no th mch pht PT 2262 ( chn 1 -> 8) cng nh vy.Sau khi nghin cu nguyn l hot ng tng khi ca mch iu khin khng dy ta tin hnh nghin cu nguyn l hot ng ca ton mch. Khi cp ngun hot ng cho mch th chn 10 -> 13 ca PT 2272 mc 0 (mc logic thp), chn RD4, RD5, RD6, RD7 ca PIC 16F887 mc thp nn tn hiu ra ca khi iu khin bng 0 nn LED6, LED7, LED8, LED9 khng c in th qua nn khng sng, khng c dng kch thch lm cho Transistor khng dn (VB 0.7V) nn li ra chn C l mc thp to ra ngun cung cp lm cho Relay bt lm cho thit b cn iu khin th nht bt.

Khi tt thit b

Khi ta nhn A remos chn 17 ca PT 2272 c tn hiu mch thu s nhn tn hiu truyn qua vo chn 14 ca PT 2272 lm cho chn 13 ca PT 2272 ln mc 1,ng vo ca vi iu khin ang mc logic cao khi nhn thm mt tn hiu na n s set ng ra RD4 xung mc logic thp , chn B(C1815) khng c dng kch lm cho Transistor ngng dn (VB < 0.7V) nn li ra chn C l mc cao, khng c ngun cung cp Relay mt in tr v trng thi ban u tt thit b th nht.

LU GiI THUT

Sn phm hon thin

3. KT LUN

Sn phm (phn cng+phn mm) m bo c mc tiu m ti hng ti. Qu trnh th nghim ti nh cng nh chy khi bo co u tt, iu khin thit b nh yu cu.Tuy vy, ti cng c mt vi hn ch nht nh nh: nhy ca thit b thu cha caoMn hnh LCD b yu ngun khi relay c khi ngKhong cch iu khin trn thc t cha c xa nh mong munVi ti ny c th m rng iu khin c nhiu hn na cc thit b trong nh.

Phn cng cho mi module cn c thu nh d dng cho vic iu khin v mang tnh thm m

ti khng nhng ch p dng cho vi cc thit b trong nh m nn c m rng p dng i vi iu khin cc thit b s dng ni cng cng. C th s dng thm cc cm bin o nhit , bo chy t ng tt cc thit b khi c s c xy ra. Hy vng vi nhng hng pht trin nu trn cng vi nhng tng khc ca cc bn, ca ngi c- nhng ngi i sau - s pht trin hn na ti ny, khc phc nhng hn ch, tn ti ca ti, lm cho ti tr nn phong ph hn, mang tnh ng dng cao hn vo trong thc t cuc sng, phc v cho nhng li ch ca con ngi trong tng lai.

CHN THNH CM N!BEGIN

KHAI BAO BIN

KHAI BO LCD

TT TT C CC THIT B V HIN TH RA LCD

RB0 = 0

RB1=0

S

RB2=0

S

RB3=0

S

RB4=0

TT THIT B 1

BT THIT B 2

RB5=0

TT THIT B 2

TT THIT B 3

RE1=0

BT THIT B 1

BT THIT B 3

RE2=0

TT THIT B 4

BT THIT B 4

S

S

S

S