Bai Tap Lon Vibaso

8/2/2019 Bai Tap Lon Vibaso

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TRNG I HC IN LC

KHOA IN T VIN THNG

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BI TIU LUN

Mn Tng Quan V Viba

H NI-2011
http://www.google.com.vn/imgres?imgurl=http://3.bp.blogspot.com/_oWch1DukJKo/TGAMtRq8doI/AAAAAAAAADA/W2b2Cz7oYtI/s200/Logo_Dien_luc2009821155210.jpg&imgrefurl=http://www.tuyensinhvn.com/2010/08/iem-chuan-2010-h-ien-luc.html&usg=__S5-2DrQwu-oALNIyXyqT4PV2Dd0=&h=200&w=196&sz=14&hl=vi&start=3&zoom=1&itbs=1&tbnid=ZyFXJK4Nt4IoiM:&tbnh=104&tbnw=102&prev=/search%3Fq%3Dlogo%2Btruong%2Bdai%2Bhoc%2Bdien%2Bluc%26hl%3Dvi%26sa%3DX%26tbm%3Disch%26prmd%3Divns&ei=kcCjTbLgBYO6ugPo-cCCCQ


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TRNG I HC IN LCKHOA IN T VIN THNG

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BI TIU LUN

Mn Tng Quan V VibaNhm1: Nguyn Vn Lun

Nguyn Duy Bo

ti : Tm hiu v thit b viba s DM2G-1000

H NI-2011

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Mc Lc

PhnI - Tng qut v thit b vi ba s DM2G -

1000. ...................... .5

I.1 Giithiuchung ............................................................................... 5

I.1.1 c im thitb ........................................................................... 5

I.1.2 Kt cu thitb .............................................................................. 5

I.1.3 Cu hnh hthng ..........................................................................6

I.1.4 Cc ch tiu kthut ...................................................................... 7

I.2 Chc nng cckhi .......................................................................... 8

I.2.1 Khi pht(Tx) ............................................................................... 9

I.2.2 Khi thu(Rx) ...............................................................................12

I.2.3 Khi bng tn c s B/U -U/B .....................................................16

I.2.4 Khi knh nghip v s DSC2.....................................................19

I.2.5 Khi hin th

DSPL ......................................................................22

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I.2.6 Gim st v iukhin .................................................................22

Phn II- Phn tch phn my pht thit b DM2G -1000 .................... 24

II.1 Khi dao ng ni(OSC) ............................................................... 26

II.1.1 S nguyn l khi dao ng ni(OSC) ................................. 26

II.1.2 Tng qut s nguyn l cakhi .......................................... 26

II.1.3 Phn tch mch trn s........................................................... 26II.1.4 Nguyn l hot

ng .................................................................. 29

II.2 Khi MODCONT ........................................................................ 29II.2.1S nguyn l cukhi ............................................................. 31

II.2.2 Nguyn l hot ng ca tonmch .......................................... 33

II.3.1 S nguyn l khi iuch .................................................. .33

II.3.2 Tng quan s nguyn lkhi ................................................ 33

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II.4 Khi khuych i cng sut siu caotn ..................................... 36

II.4.1 Tng quan s nguyn l khiHPA ........................................36


Phn I Gii Thiu Chung

I.1.1. c im thit b

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DM2G - 1000 l thit b vi ba s c dung lng l 16Mbit/s (gm 8 lung 2Mbit/s), t hp cc khi chcnng cn thit, bao gm c phn Radio v Modem

trong mt khung gi my n. Tt c cc khi chcnng c chia ra trn mt s mch in nh, gnnh vi tch hp linh kin cao. DM2G - 1000 dng gi, vn chuyn, lp rp v d dng cho vickim tra li tuyn. Thit b bao gm nhng chc nngchnh nh sau:-Ngun cung cp-Thu pht v tuyn

-iu ch v gii iu ch-Knh nghip v-Phn nhnh RF-Panel hin th cc ch tiu k thut c bn-Kim tra v gim st-iu khin v gim st t xa

I.1.2 Kt cu thit b

Tt c cc mch chc nng v khi mng phn nhnh(BR NTWK) gm cc khi:ngun, pht, thu, iu khin, gim st, knh nghipv... nm gn trong mt thng kim loi. Mt trc thngc th c tho ri quan st. Khi mng phnnhnh (BR NTWK) c gn vo khong khng gianpha di cc khi mch (y thng).

*Danh mc cc khi chc nng+ Khi pht (TX)+ Khi x l pht (TDP)+ Khi dao ng (OSC)+ Khi iu ch (MOD)+ Khi khuych i cao tn (HPA)+ Khi thu (RX)+ Khi nhn v gii iu ch IF (IF DEM)

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+ Khi chuyn i tn hiu thu (R CONV)+ Khi bng tn c s (B-U/U-B)+ Khi gim st logic (SVLG1)

+ Khi knh nghip v (DSC2)+ Khi ngun (PS)+ Khi hin th (DSPL)+ Khi chuyn mch (TSW)+ Khi chuyn mch thu (RSW)+ Khi mch phn nhnh (BR NTWK)

I.1.3 Cu hnh h thng .

DM2G - 1000 c th phc v linh hot cho cc tuynvi ba c nh ni chung v cc trm vi ba di ng niring. Trong phm vi c nh, DM2G - 1000 c th tothng mt trm u cui, mt trm chuyn tip hocmt trm trung gian c xen r. Chng ta biu din mttuyn vi hai trm u cui dng thit thit b DM2G-1000 theo cu hnh 1+0 nh hnh v sau (ch minh

ho mt chiu).

S ng dng DM2G - 1000 cho mt tuyncu hnh 1+0

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+ Thit b khng c d phng 1+0.+ Cu hnh 1+1: Thit b d phng nng (s

tng t nh trn nhng c hai khi pht v hai khithu i km cc chuyn mch pht v cc chuyn mchthu).+ Cu hnh n+1: C rt nhiu my hot ng nhngch c mt my d phng cho c n my.

I.1.4 Cc ch tiu k thut

a- c tnh v tuyn.Thit b DM2G - 1000 hot ng trn mt di tn t2000 n 2100 v 2200 n 2300 (MHz)Trong bng tn cho, tn s c chia thnh 5,6cp cc cp ny thng i vinhau. DM2G - 1000 vi tn s trung bnh 2GHz cchia thnh 5 cp sau y:

1) 2038 1) 2213,52) 2052 2) 2227,53) 2066 3) 2241,54) 2080 4) 2255,55) 2094 5) 2269,5

n v: MHz. Nh vy bc nhy lin tip gi hai tns l 14 MHz, khong cch gia tn s thu v tn s

pht l 175 MHz.Cc tn s 1, 2, 3, 4, 5, gi l tn s thp.Cc tn s 1, 2, 3, 4, 5, gi l tn s cao.

b- c tnh c kh v iu kin hot ng.-Kch thc vt l:

+ Rng : 448mm+ Cao : 325mm+ Su : 450mm

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-Khi lng: 30 kg-iu kin v ngun: in p mt chiu cung cp

(DC) l -24V

hoc -48V (-19V n -60V).-iu kin v mi trng:+ Nhit xung quanh: 0 n 45oC+ m tng i: Ti 95%+ cao t my: c 4000 m so vi mc nc bin

(thng li dng a hnh i, ni, vng cao).

I.2 Chc nng cc khi

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S khi tng qut my DM2G -1000

Tng quan s gm c:+ Khi pht: 2 khi trong c cu d phng nng TX

No1 v TX No2+ Khi thu: Cng gm hai khi RX No1 v RX No2+ Khi bng tn c s: B-U/U-B+ Khi knh nghip v s: DSC2+ Khi logic gim st: SVLG1+ Khi hin th: DSPL1 (Display 1)

I.2.1 Khi pht (TX).

V TX No1 ging ht TX No2 nn ta trnh by vi 1trong 2 thit b:

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S khi phtKhi pht gm 4 khi chc nng sau:+ Khi x l d liu pht (TDP)+ Khi dao ng (OSC)+ Khi iu ch (MOD)

+ Khi khuych i cng sut siu cao tn (HPA)

a- Khi x l d liu pht (TDP).

Tn hiu t bng tn c s mun pht i phi cx l ti TDP: Nhim v ca khi TDP- Chuyn i t ni tip ra song song

- Chuyn i tc d liu: (2 lung)8,448 Mbit/s x 2 9,01764 Mbit/s x 2

- Ghp knh d liu ca:+ Bit d liu chnh (ti t B-U/U-B)+ Bit d liu nghip v s (t DSC2)+ Bit ng b khung+ Bit kim tra chn l+ Bit iu khin chn

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+ Bit nhn dnh ng- Trn (Scrambling)- M ho vi sai

- Gi tn hiu cnh bo. Cc thng s k thut:- D liu chnh vo: 8,448 Mbit/s x 2 t B-U/U-Btng thch vi mc NRZ TTL (m khng tr v 0 vimc ngun +5V)- Tn hiu ng h vo: 8,448 Mbit/s x 2 (t B-U/U-B).- Tn hiu nghip v vo: 140,9kb/s x 2 t DSC2.- D liu ng h DSC vo: 140,9kb/s t DSC2.

- D liu chnh ra: 9,01764 Mbit/s x 2 ti b iu ch Cnh bo:- Cnh bo vo: B IN LOOS 1,2: Cnh bo c bo tB-U/U-B khi tn hiu lng cc b mt. Mc cnh bol TTL (mc H 5V)- Cnh bo ra:

+ SIG IN: Xut hin cnh bo khi tn hiu chnhhoc tn hiu DSC vo b

mt. Mc tn hiu l TTL.+ TPWR (cnh bo cng sut pht): Xut hin cnhbo khi mc cng sut pht nh hn cng sut danhnh 3dB. Mc cnh bo l TTL (mc H).

b- Khi dao ng.

OSC: To tn hiu RF, c s dng cho h iu

ch trc tip tn hiu RF.N to dao ng ni, ttn s dao ng ni TX chnh

l tn s pht (v y khng iu ch tn s miu ch 4 - QAM).Tn s dao ng ni c to bi khi dao ngiu khin in p (VCO) di s cng bc camch vng kho pha PLL (Phase-Lock-Loop). Cc thng s k thut:

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- Di tn: 2000 MHz n 2150 MHz v 2150 MHzn 2300 MHz.- n nh tn s: 10 ppm.

- Mc ra RF: - 5dbm 1dbm.- Mc ra hin th (MON): - 15 dbm.

Hot ng ca mch:- Tn s dao ng ni ca VCO c iu khin

bng vng lp kho pha.- Tn s PPL quy chiu l 8MHz, tn s so snh l250 MHz v bc gin on l 500 KHz.- u ra VCO c khuych i v lc tr loi

hi bc cao, sau a n cng RF OUT.

c- Khi iu ch (Modulation).

Khi ny iu ch hai lung tn hiu 9,01764 Mbit/sn b TDP.Tn hiu ngoi sai (dao nh ni) c ly t b daong OSC, n iu ch sng mang trc tip.

Phng thc iu ch y l iu bin cuphng (4-QAM, 4 mc l 00,01 10,11). Cc thng s k thut:- Di tn: 2000 MHz n 2150 MHz v 2150 MHzn 2300 MHz.- Mc tn hiu vo: -5dbm 1dbm.- Tn hiu ra iu ch: -5dbm 3dbm- Li pha: Nh hn 50

- Tn hiu c iu ch: 800 mVpp Hot ng ca mch:- Tn hiu ra RF (-5dbm) sau b TDP c khuych

i v chia lm hai phn bng nhau bng mch phnchia sai ng a vo thc hin iu ch. Tn hiuny c tn s ng bng tn s sng mang ca mypht ra.

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- Hai lung d liu (S1 v S2) 9,01764 Mbit/s ly rasau b x l d liu pht (TDP) c gi ti b iuch MOD (vi phng thc 4-QAM) iu ch sng

mang pht. Tn hiu ra t b ny l tn hiu siu caotn c iu ch.- Sau tn hiu trn c a vo b khuychi HPA x l,.

c- Khi khuych i cng sut siu cao tn (HPA).

Tn hiu u vo ca HPA l tn hiu ra sau khi

MOD, c mc l(-5dbm), b HPA khuych i n ln n (+33dbm) pht i. Cc thng s k thut:

- Di tn s: 2000 MHz n 2150 MHz v 2150MHz n 2300 MHz

- Mc tn hiu vo: -5dbm (tn hiu ciu ch).

- Mc cng sut ra: + 33dbm Hot ng ca mch:

HPA bao gm mt b khuych i RF, VATT (bsuy hao bin i), b phn chia v b khuych isiu cao tn. Tn hiu trn u ra ca b HPA ca ti b BR NTWK (mng phn nhnh - Branchingnetwork)Nh vy khi pht TX gm 4 chc nng chnh v

nhiu chc nng con nh k trn cng vi nguyn lhot ng cng nh cc thng s k thut ca chng.Vi s quan st thc t chng ta thy rng khi ny rtgn nh d tho ri v n l thit b s c cu tobng cng ngh vi in t (vi cc mng mch IC c tch hp cao - LSI). Mt khc cng sut pht camy l nh (33dBm), v cc anten thu pht t cao,suy hao do mi trng truyn dn khng trung nh.

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Cc mc in mt chiu DC cung cp l thp (-5Vn +10V), s rt tit kim, an ton, cng sut tiuth ton h thng l 110W (nh).

I.2.2 Khi thu(RX).

Gm RX No1 ging ht RX No2. Ta ch cn xt 1 mythu RX No1:

S tng qut khi thu1 (RX No1)

S khi chi tit ca RX No1

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a-Chc nng c bn ca khi.

+ Chuyn i tn hiu thu 2GHz v dao ngng b thnh mt tn hiu trung tn IF 70 MHz.+ To dng ph ca tn hiu IF.+ iu chnh mc tn hiu ra IF bng b iu

lng AGC.+ Gii iu ch tn hiu 4-QAM: Loi b sng

mang trung tn, thu li lung tn hiu.+ Phn chia lung tn hiu, tch ra d liu chnh,

d liu DSC, xung ng h, bit kim tra chn l, bitthng tin v chn.b- Cc thng s k thut.+ Tn s thu: 2000 n 2150 MHz v 2150 MHz

n 2300 MHz+ Mc tn hiu thu: -42 dbm n -90dbm/50+ Tp m: 4dB l in hnh+ n nh tn s ni: 10 ppm

b-Cc cnh bo.

+ PLL (tn cnh bo): Bo hiu rng mch PLL cadao ng ni b mt n nh.+ LEVEL (mc): Khi mc ra ca trung tn nh hn

(-15dBm) tiR CONV+ BER (t l li): Khi BER c pht hin bi vic

kim tra chn l qu mt trong nhng gi tr ttrc. Mt trong nhng BER di y c th ttrc: 10-4, 105,106,107...+ FRAME (khung): Xut hin khi ng b khung

cho lung d liu chnh b mt.

c- Cc khi chc nng con.

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RX No1 gm 7 khi (xem s ): LNA, MIX,VCO SYN,IFA, DEM, VCO, RDP.

* Khi LNA (khi khuych i cao tn v hn ch tpm thp):Khuych i tn hiu thu RF (2GHz) v tn hiu nyb suy hao trn ng truyn nn cn rt nh (mcd truyn dn s suy hao nh hn nhiu so vi truyndn analog).* Khi VCO SYN (khi t hp dao ng):B to dao ng phc v cho vic trn tn khi MIX.

B dao ng ny c s dng cng vi mch vngkho pha (PLL).

d-Khi MIX (b trn tn).

Thc hin trn tn i tn, chuyn i t tns cao (siu cao tn 2GHz) xung tn s thp (trungtn IF 70 MHz).

Gi ft l tn s thu ( 2GHz)F l tn s dao ng ni Th tn s trung tn fIFsau b trn c tnh:Fif = fthu - fd Bit fIF = 70 MHz ta c th tnh ton

c c fd n nh tn s dao ng ni yu cu 10-5.f- B IFA (IF amplifier - khuych i trung tn).Tn hiu trung tn va c to ra sau b i tn sc khuych i ti y c bin ln a vo b x l ti b IF DEM. ng thi ti y(IFA), tn hiu trung tn cng c lc hn chtp m ca n. Ngoi ra b IFA cn lm nhim v:

+ iu chnh h s khuych i (AGC)+ Lc dng ph tn hiu trung tn+ Cnh bo ra khi tn hiu IF c s c.

* B VCO (B dao ng iu khin in p)

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To dao ng ni phc v cho vic gii iu ch 4-QAM loi b sng mang trung tn IF, thu li lung tnhiu ban u c pht.

* B DEM (gii iu ch)B ny c chc nng: Kt hp vi b to dao ng ni

(VCO) thc hin gii iu ch, pha pht tin hnhiu ch theo phng thc 4-QAM, cho nn pha thu y s l gii iu ch 4-QAM.* B RDP (b x l tn hiu thu)C cc nhim v sau:+ Khi phc tn hiu gi i t tn hiu b trn

+ Tch xung ng h (khi phc bit timing)+ Tch bit ng b khung+ Tch bit kim tra chn l+ Tch bit DSC ri a n b knh nghip v+ Tch bit iu khin chn+ Tch bit nhn dng ng+ Gii trn+ Gii m vi sai

Khi thu c hai b thu s1 v s 2 lun cng lm vicng thi (khc vi pha pht), tn hiu a vo x ltrong tng i s l tn hiu thu tt nht trong 2 my1,2. Vy mc d mi trng truyn dn vi ba c nhiutp m, xuyn m nh hng nhng cht lng tnhiu vn m bo trn mi lnh vc.

I.2.3 Khi bng tn c s (B-U/U-B).

Khi ny gm hai phn chnh:- Khi B-U (lng cc sang n cc) pha pht- Khi U-B (n cc sang lng cc) pha thu

a- Khi B-U (phn pht).

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Nhn cc lung d liu t tng i s, gii m HDB-3 v cung cp hai lung n cc vo 2 khi TX (khipht).

S y khi chuyn lng ccsang n cc

* Chc nng:+ Chuyn i lng cc sang n cc (B-U CONV)+ Gii m HDB-3 (HDB-3 decode)+ Ghp 8 knh 2Mbit/s thnh 1 knh 16 Mbit/s (MUX)+ Cn bng suy hao cp+ Khi phc xung ng h (clock)+ Pht hin tn hiu cnh bo (AIS).

* Cc thng s k thut:Vo Ra8 lung 2,048 Mbit/s 2 lung 8,448 Mbit/s

(NRZ)* Cnh bo:

B IN LOOS (mt tn hiu vo): Cnh bo khi mt haynhiu tn hiu lng cc tikhi ny b mt (mc H - 5V ca TTL) c a ti

phn gim st (SV).

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+ AIS REC (ghi nhn cnh bo): Khi mt hay nhiutn hiu u vo lng cc tikhi ny l AIS, mc H ca TTL c a ti phn

gim st (5V).* Nguyn l hot ng:8 lung d liu HDB-3 2,048 Mbit/s c a vo

b cn bng cp theo khuyn ngh G.703 ca CCITT.u ra cn bng c chuyn i U-B v gii mHDB-3 thnh n cc NRZ (khng tr v khng). Cctn hiu n cc c ghp bi 12 MUX t 8 lung2,048 Mbt/s thnh 2 lung 8,448 Mbit/s. Khi ghp tn

hiu n cc c phn lm 2 cho TX No1 v TXNo2 khi tn hiu vo HDB-3 b mt, cnh bo cgi ti khiSVLGC1. Khi tn hiu vo l AIS, AIS REC c gi tikhi SVLGC1.

b Khi U-B (phn thu).

* Nguyn l hot ng:Cc tn hiu n cc a ra 2 lung 9,01764

Mbit/s t RSW ly t thu 1 v thu 2, iu khin bi8 xung ng h. U-SW trongRSW t ng iukhin chuyn mch gia lung d liu No1 v No2

bng cc lnh chuyn mch t khi logic gim sthc bng vn hnh nhn cng qua vic gtchuyn mch SW mt trc card. D liu cchn s

c chuyn t song song ra ni tip. D liuc phn chia bi 2 khi DEMUX (tch knh) tlung s liu s 2 thnh 4 lung d liu th nht.

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Lung d liu 2,048 Mbit/s c m ho HDB-3,chuyn i U-B v c a ra. Khi mt tn hiuli ra HDB-3 cnh bo B OUT FL (li u ra nh

phn) c gi ti khi logic gim st (SV LGC1). Khitn hiu li ra l AIS, th AIS SND (gi tn hiucnh bo) c a ti khi SV LGC1. AIS cngc gi ti khi c my thu 1 v 2 c cnh bo ura (RX ALM).

Khi B-U/U-B c gi l khi bng tn c s vtn hiu y l tn hiu thuc knh c bn

2Mbit/s (ly t tng i s), cha c iu chv x l pht, cng nh n c tr li nguynbn t sau khi thu. Chc nng chnh ca khi nyl chuyn n cc thnh lng cc (v ngc li),ghp knh (v tch knh) v tn hiu u vo(hoc ra) l di dng m ng, tn hiu ghp, chn x l vi tn hiu nghip v li l didng m ,nh phn n cc (nn phi bin i).

Ti u vo ta khng th dng m nh phn ncc c m phi dng m ng lng cc v mnh phn n cc b tiu hao rt nhiu trnng truyn dn. C rt nhiu dng m ngnh AMI, CMI, B3ZS, HDB-3...

M ng trong vi ba thng dng Ami hocHDB-3 (trong cp quang th thng dng B8ZS),trong HDB-3 c dng nhiu hn v n trit

tiu gn nh hon ton thnh phn mt chiu do m bo c cht lng cng nh s ngin ca ng truyn. Khi bng tn c s cngrt gn nh, d tho ri vi s ng dng cng nghvi in t.

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S khi U-B

I.2.4 Khi knh nghip v s (DSC2).

a- Cc thng s k thut.

* Knh tn hiu tn s m thanh (VF):+ Di tn s vo/ra: 0,3 - 3,4 KHz

+ Mc tn hiu vo ra danh nh:

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Vo : (-14 n -4 dbm)Ra : (-4 n +7 dbm)

+ Tng tr vo/ra: 600 cn bng

* Knh nghip v:+ Di tn s vo: 0,3 n 3,4 KHz+ Mc tn hiu vo, ra danh nh:Vo : -4 dbmRa : -4 dbm+ Tng tr vo/ra: 600 cn bng

b- Hot ng ca khi mch.

* Khi ghp knh, phn knh:Cc chc nng ghp knh chnh l:+ Ghp 4 ng d liu 64 Kbit/s (2 ng

thm)+ Chuyn i 1 lung d liu ni tip thnh 2

lung s liu 140,9Kbit/s.+ Ghp bit ng b khung

Cc chc nng phn knh chnh l:

+ Kt hp 2 lung d liu 140,9 Kbit/s thnh mtlung d liu.

+Phn knh lung d liu c 4 lung dliu 64 Kbit/s

+ ng b khung.Mt trong hai tn hiu u ra (tn hiu ra

phn knh s 1 hoc tn hiu ra phn knh s 2)c chn bi mch iu khin tn hiu u raDEMUX.

No1 v No2 c cho cng mc u tin. Khi lica No1 v No2 do mt ng b

khung hay li xung nhp phn knh 192 KHz,mch iu khin tn hiu ra DEMUX chn phnDEMUX tt nht.

* Khi giao din s hay m ho PCM:

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Mt trong cc mch in ph giao din s v m hoPCM la chn c t trn mch in chnh DSC2.

+ Khi giao din dng truyn cc ng s

liu 64 Kbit/s.+ Khi m ho PCM dng pht tn hiu tng

t. B m ho PCM chuyn mt tn hiu tn s mthanh sang ng s liu 64 Kbit/s v b gii mPCM chuyn ng s liu 64 Kbit/s sang tn hiutn s m thanh.

* Khi mng phn nhnh:Mng phn nhnh ny c 5 cng vo ra cho cc

tn hiu m tn, 1 tn hiu voc chia lm 4 hng.* Khi m ho, gii m PCM (PCM CODEC):Khi m ho PCM chuyn tn hiu tng t sang

tn hiu s (analog sang digital).

c. Khi ni tip tn hiu s (DIG CON).

Khi ny c 4 cng vo/ra truyn tn hiugim st v tn hiu iu khin t xa. Mt trong 4s liu vo c gi ti 3 cng u ra khc theoth t.

d. Khi in thoi nghip v.

Khi ny c cung cp mt in thoi nghip

v hot ng vi chc nng la chn cuc gi.Cc chc nng chnh l:+ La chn cuc gi+ Gi ti mi trm+ C th gn 2 s c lp vi trm+ Gi thoi

Ngoi lung d liu chnh (thoi, s liu) vi mcch o th, kim tra bo dng, ngi ta a

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khi DSC2 vo. N s gip cho ngi vn hnh gimst c ton b thit b, ng truyn.

I.2.5 Khi hin th (DSPL).

Khi ny c cc chc nng sau:- in thoi nghip v TEL- Hin th chung

COMMON- Hin th gim st

SUPERVISORY

- Hin th cnh bo v i trng thi ALM /STATUS

- B o ch tiu trn my myMONITOR

- iu khin chuyn mch TSW,RSW.

I.2.6 Gim st v iu khin.

S kt ni tuyn vi ba

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Trm lp li

iu khin v gim st t xa cc trm ucui v trm lp c kt ni nh hnh v trn.

+ Gim st: Mi lin lc gia cc thit b v tuyn

c tin hnh bng phng php quay vng,thit b v tuyn ch gi tn hiu gi ti thit b vtuyn khc. Cc thit b c gi tr v, tin tcgim st bao gm cnh bo, trng thi thit b v dliu biu th li. iu ny dc thc hin tun ttng thit b v tuyn ti mi thi im cho tt ccc

thit b v tuyn trong h thng. D liu thit

b v tuyn cho ti tm trm v tuyn c lu gitrong b nh ca khi gim st v la chn d liuthit b bng nt EQPNo trn mt hin th.

+ iu khin t xa: Thit b v tuyn cquyn hi p v c th thc hin vic iu khint xa chuyn mch d phng v cc iu khint ngoi khc. Thit b v tuyn ny gi cc lchiu khin t xa ti cc thit b v tuyn c

chn.

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iu khin v gim st t xa l mt chc nngquan trng cp cao ca thit b vi ba s DM2G-1000, mt chc nng m t loi my vi ba khc ang

tn ti trn th trng Vit nam c c. N thunli cho vic thu thp thng tin nhanh bo dng,x l s c nu c xy ra trong cc mng li vi bakhu vc.

PhnII- Phn tch phn my pht thit bDM 2G - 1000

Chng ta nghin cu v thit b vi ba s DM2G-1000 vi cc s khi chc nng, trong phnny chng ta i nghin cu k hn v s nguyn l mch khi pht (TX). Khi pht (TX) gm 4khi chc nng c bn: TDP, OSC, MOD v HPA Khi

MOD CONT l mt b phn quan trng ca khiMOD, n lm nhim v bin i, iu chnh haidng tn hiu vo S1, S2 trc khi a vo iuch. Trong khun kh c hn ca bn n chngta s nghin cu 5 khi sau: TDP, OSC, MOD CONT,MOD v HPA.

- Cc k hiu trn hnh 4.1 th hin cc nghasau:

- SP PLL: B so pha trong c cu mch to daong OSC c vng lp kho pha.

+ B sai ng, phn ng, bin p.+ 1/N: B chia tn vi h s chia N.+ VCO 1: B to dao ng iu khin bng

in p.+ B khuch i.+ T: B suy gim.+ R: Ca ra ca b khuch i cng sut.+ LOF MON: im o v hin th tn hiu tn s

dao ng ni.

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+ RF MON: im o v hin th tn hiu caotn.

+ RF OUT: u ra cao tn a ti Anten.

+ PLL ALM: Cnh bo khi PLL mt xung ng b.+ ALC CONT: iu khim thay i mc vo HPA

t ng.+ TLVL DET: Pht hin mc cng sut pht ra t

HPA. Tm tt nguyn l hot ng ca cc khi ny:ALC MNL (iu chnh bng tay mc t iu

lng): Khi ALC t OFF bng nhn cng

(MANUAL), mc cnh bo TTL (mc H) a ran SV LGC 1. CW ON (pht sng mang): Khi CWON c t, mc cnh bo TTL H c a tiSV LGC 1.

T PWR TVL MON (Kim tra mc cng sut pht): (0 +5)V TX in p hin th bng in p. ID (Sng ng): C th c chn t 1 8, qu trnhthit lp c thc hin trn

BWB (Tm u dy).

Nguyn l hot ng ca ton mch:

Hai lung d liu chnh 8,448 Mb/s v xungng h t B-U ca U-B c a ti LSI.

D liu chnh vo t B-U/U-B c bin i tc t 8,448 Mb/s n 9,01764 Mb/s sau hp li

vi d liu DSC. Sau khi trn, cc bit chn thm nhBit ng b khung, Bit nhn dng lung ID v Bitkim tra chn l c hp li. Hai lung d liuc a ti b MOD. Khi B IN LOSS c bo tkhi B-U/U-B, b pht tn hiu TDP ca LSI (DP) phttn hiu cnh bo (AIS). AIS cng c x l nhd liu bnh thng. Hai lung d liu DSC IN bmt, cnh bo SIG IN xut hin v SIG IN LED sng

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trn Panel ca TX. TDP c trng cho mchgiao din ALM (cnh bo), MON v iu khin ALC.Mc cng sut pht ra c hin th bng b pht

hin mc cng sut ra TX caHPA (B khuch i cng sut siu cao tn). in

p ra DC ca b pht hin (TLVL DET) c s dngcho ALC v TLVL MON.

gi n nh cng sut pht RF, ALC iukhin b suy hao bin i (VATT) trong HPA theocch ngc vi in p ra ca TLVL DET. Tn hiu ra

TLVL DET c gi ti SV LGC 1 iu khin

cng sut pht ra. B TDP nhn mt cnh bo PLLkhi PLL ca OSC c s c lp kho pha. TDP chuyncnh bo ti SV LGC 1. CW CONT (ni sng mang)c iu khin bi SW2. Khi n SW2 ch vnhnh ca TX c t l CW ON v sng mangkhng iu ch t TX.

in p nui c cung cp t PS (+10 V v +5V)c cp ti HPA qua chuyn mch ngun nui ca

TDP. B chuyn mch ny c t l ON khi xcnh rng hot ng ca PLL v OSC l bnhthng.

Khi mt cnh bo PLL c pht hin, chuynmch t ng t OFF v ct ngun nui ti HPA.

II.1 Khi dao ng ni (OSC)II.1.1 S nguyn l khi dao ng ni

(OSC).II.1.2 Tng qut s nguyn l ca khi.

B to dao ng iu khin bng in pVCO1 (Voltage Contronlled Osalater 1).

+ Mch pha: IC6 ca mch in lin quan.+ Mch chia tn IC5, IC2.

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+ Mch khuch i tn hiu dao ng a ra:IC3, TR2 v cc mch in

lin quan.

Phn ngun nui cung cp IC7, IC8 v cc t lc.

II.1.3 Phn tch mch trn s .

a- B to dao ng iu khin bng in p(VCO1)

u vo VCONT tip nhn mt in p iu

khin Ud t IC6 sau khi c IC7 1/2 khuychi. u vo 5V tip nhn, in p mt chiu t bphn cp ngun cho VCO1 lm vic.

Mt u GND ni t.u ra RF OUT cho tn hiu ra tn s bng 2GHz

thng qua cc mch lc, suy gim ri tch ra lm 2ng, 1 ng l mch chia tn a v so phati IC6, 1 ng l khuych i tn hiu dao ng

ni a n u ra CN1.Cc in tr R11, R12, R13, R16, R17,R18 ng

vai tr l tc dng suy gim scng nhiu v ngc li.

b- Mch so pha.

Nhiu ti liu cho rng PLL bao gm c cc khi

VCO tch sng pha chia tn lc thng thp vkhuch i, nhng trong s ny IC6 ch ngvai tr mch tch, so pha v lc thp.

Trc ht chng ta ni v chuyn mch t SW1n SW4. Nhim v ca chng l t tn s pht.

Trong mi SW1 c 4 chuyn mch nh l c cuchuyn mch bng cc Triger trong h nh phn.

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OSC 1 l b to dao ng tn s nh bng thchanh, tn s ny khong 8 MHz v rt chun. Tnhiu to ra t b ny c dng lm tn hiu u

vo cho mch vng kho pha, tn s hoc pha av so snh t b VCO1 c kho vo tn s hocpha ca tn hiu ny.

IC6 nhn tn hiu mt chiu cung cp ngunnui mc +5V sau khi c lc nhiu ln v atn hiu cnh bo mt xung ng b PLL ra chns 2 ca CD1.

ng thi IC6 nhn tn hiu t u ra b VCO1,

c khuch i, chia tn lm tn hiu nh i so pha vi tn hiu vo t b OSC1.

c tn hiu iu chnh Ud t l vi hiu pha =v -r (v l ca tn hiu OSC1, r lca tn hiu vo IC6 t mch chia tn), th ta phidng mt b tch sng pha (trong IC6) u ra btch sng pha l tn hiu iu chnh c an b to dao ng

khng ch bng in p VCO1.V U1 = KUv. Ur.

Nn trong tn hiu ra b tch sng pha c ccthnh phn tn s.

(v - r) hoc (v + r). Tn s tng b loi bnh b lc thng thp trong IC6 v u vo IC7,cn tn s hiu c khuch i ln nh IC7 vc dng lm tn hiu iu khin tn s daong ni ca VCO1. Tn s VCO 1 c thay isao cho (v - r) 0: ngha l fr = fv hoc fr = Nfv vi N l h s chia ca b chia tn.

Cc t C41, C43, C44, C45 lm chc nng t lcngun +5V.

(R41, R43, C51), (R42, R44, C52) l tr khng voca IC7 nhng ng thi cng lm chc nng mch

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lc thng thp ch cho thng tin hiu c tn shiu (Cov - Cor). R34 cp thin p cho TR1 lm vic.R46, R54 l tr khng vo v R27, C56 l tr khng

ra, R45, C53 nm trong mch vng hi tip ca bkhuch i.

c- Mch chia tn.

IC5, IC2 v cc mch lin quan. Mch chia tn lcn thit bi v n i tn s fr ca b VCO1 (rtln) xung tn s fr nh (fr + fr/N) c th

so snh vi tn s vo t b OSC1. Trc khi cchia tn IC5, tn hiu t u ra b VCO1 ckhuych i ln ln nh IC2.

C63, C34 l t lc ngun cung cp cho IC5 v IC2lm vic. C19, C25, C31, C35 ngn cch mt chiugia cc tng.

R29 lm nhim v n nh tr khng ra v trkhng vo cho IC2 v IC5.

Cc linh kin cn li lm nhim v ti lc xoaychiu cho cc IC lin quan.

d- Mch khuych i tn hiu dao ng (IC3,TR2).

Tn hiu t u ra b VCO1 sau khi qua cc bsuy gim nh, lc, c a n khuych i s

b ti IC3, li qua cc b suy gim ri c khuchi ti TR2. Tn hiu u ra TR2 ln qua bsuy gim nh ri a ra ngoi qua jc cm CN1.R61, R62, R63 lm thnh b suy gim. (R51, R52,R53), (R21, R22, R23) cng l cc b suy gim u ra ca hai tng khuych i.

C11, C12 l cc t ni tng. C28, C64 l cc t lcngun mt chiu cung cp cho RV1, R56, R55, R54

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l cc in tr trn ng cp in phn p choTR2. R58 v C6 dng n nh tr khng vocho TR2, R59 v C9. it D2 v R57 trong c cu

bo v qu p cc linh kin cn li l ti cho ccphn t khuych i.

e- Phn ngun cung cp.

IC7, IC8 v cc t lc.IC7 l IC dng n nh in p ngun cung

cp kiu tham s. IC8 l IC dng n nh in

p ngun cung cp kiu b.L1, C6, C62 to thnh mt mt lc thng thp

hnh .C69, C65, C66 l cc t lc ngun c in p

mt chiu bng phng cung cp cho cc phn ttch cc cho mch lm vic.

II.1.4 Nguyn l hot ng.

VCO1 to ra tn s dao ng 2GHz, tn hiu ctn s ny c chia ra thng qua

cc mch lc, suy gim ri phn thnh hai nhnh:+ Nhnh 1 qua cc b khuch i ra ngoi.+ Nhnh 2 qua mch chia tn a v so pha ti

IC6 vi tn hiu vo.Tn hiu vo y l tn hiu to bi khi dao

ng nh OSC1.OSC1 thng c kt cu bng thch anh to ra

mt tn hiu dao ng c tn s nh v tn sgia tn hiu vo v tn hiu ra, ngha l PLL lmcho tn s Cor ca tn hiu so snh bm theo tns Cov ca tn hiu vo, tn s ca tn hiu sosnh t l vi tn

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s ca tn hiu ra t b VCO1 theo mt t l no do b chia tn:

c tn hiu iu chnh Ud t l vi hiu pha - r th ta phi dng b tch sng pha. ura b tch sng pha l tn hiu hiu chnh Ud c

a n b to dao ng khng ch bng inp. Nhng tn hiu ra t b tch sng pha bao gmhai tn s COv - COr v Cov + Cor, nn ngi taphi dng b lc thng thp loi b tn s

tng, tn s hiu c cho qua v khuch iln, v c dng lm tn hiu iu khin tn sdao ng ca VCO1 chc nng ny do IC6 v IC7(1/2) m nhn. Cc chuyn mch SW1, SW2, SW3,

SW4 c gn lin vi IC6 iu chnh tn sdao ng ni pht ra. Tn s to ra ny di 2GHz,nhng c chia lm nhiu cp khc nhau bng2GHz. Cc chuyn mch ny s quyt nh cp tns no s c dng thu v pht. T s tathy nu khng c tn hiu vo OSC 1 khng lmvic th tn hiu hiu chnh a vo VCO1 l Ud= 0, mch VCO1 dao ng ti tn s dao ng ringCD1 ca n. Lc ny s c cnh bo PLL mt xungng h a ra chn s 3 ca CD1 (hnh v).

Khi c tn hiu vo, b tch sng pha IC6 s sopha vi tn s ca tn hiu vo vi tn hiu so snh..a ra vi tn hiu iu khin Ud qua lc thngthp v khuch i iu khin tn s dao ngni ca VCO1.

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Tn hiu t u ra b VCO1 sau khi iukhin kho pha s c a ra qua cc tngkhuch i IC3, TR2 cho ln a ra jc CN1 ni

vo khi MOD tin hnh iu ch.Ngun mt chiu +10V t chn s 2 ca CD1

c lc rt k bi cc t C61, C62 cun cm L1 vc n nh bi cc IC7 v IC8. Qua cc phnmch ny ngun +10V b suy gim cn +5V, inp mt chiu ny c lc tip ri a n nuicho cc phn mch khc.

Nu tn s tn hiu vo v tn hiu so snh lch

nhau qu nhiu lm cho tn s tng v tn s hiuu nm ngoi khu vc thng ca b lc th khngc tn hiu iu khin VCO. VCO s dao ng titn s dao ng ring v v r ri vo khu vcthng ca b lc th VCO bt u nhn tn hiuiu khin, thay i tn s dao ng ni can, PLL

bt u lm vic, ta ni PLL l di tn s m c

th thit lp ch ng b, Di bt ca PLLph thuc vo di thng ca b lc. Di gi caPLL l di tn s m PLL c th gi c ch ng b khi thay i tn s tn hiu vo. Digi khng ph thuc

vo di thng ca b lc m ph thuc vo bin in p iu khin v kh nng bin i tns ca VCO.

II.2 Khi MOD CONTII.2.1. S nguyn l ca khi (MOD

CONT).

B MOD CONT lm chc nng bin i mc lungtn hiu vo ly t khi x l d liu pht TDP trckhi a vo iu ch ti MOD. Hnh v 1.4

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a- Tng quan s nguyn l khi.

Hai ng bin i tn hiu dn n cc u

ra S1 OUT v S2 OUT.Hai ng cp ngun +10V v -10V.

b- Phn tch tng ng tn hiu.

+ ng bin i tn hiu dn n S1 OUTng ny lm nhim v khuych i, lc thng

thp v khuych i c iu chnh IC1 l mt

phn t khuych i s b tn hiu trc khi avo lc thp.

TR1 v TR2 l 2 Tranzitor lm chc nng khuychi c iu chnh (iu chnh phn p v iuchnh mc ra).

TR1 l Tranzitor ngc (NPN) mc lp Emiter c tr khng ra nh thun tin cho vic phi hp trkhng vi tng sau, khuch i dng in ri a

n u vo TR2.TR2 l Tranzitor loi PNP cng c mc lp

Emiter khuych i dng in tn hiu vi s iuchnh phn p BNDCRT (Bin tr in t) tn hiura S1 OUT c ly t chn E ca TR2 vi s iuchnh mc ra bi RY1. R5, R2, R4 l cc in tr suygim. R8, R6 dng n nh tr khng cho phnmch pha sau. L1, C1, C20, C3, C22, L2 l cc phn t

trong c cu mch lc thng thp. in cm chn cctn s cao v t in ngn mch chng xung t.L8 dng cha tn hiu cao tn (hi bc cao).R20//L8 n nh tr khng, R9 dng nh thincho chn E ca TR1. R12 dng nh thin chochn E ca TR2. R10 l mt phn ti ca TR1 v cngl in tr ghp gia hai tng khuych i.

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RV1 l bin tr dng iu chnh mc ra S1-OUTcho hp l.R11 dng cp thin p cho chn B ca TR2, RV2,

RV3, RV4 dng iu chnh mc nh thin cpcho TR2.C5 l t trit tiu tn hiu cao tn phn x. C6 l tphi hp tr khng v cho TR2 v lc tn s cao.+ ng bin i tn hiu in dn n S2 OUT:ng ny lm chc nng nh ng 1 nu trn,hon ton tng t c phn mch in v nhim vca tng linh kin. IC1-2 ging nh IC1-1.

TR3 v cu to v hot ng ging nh TR1. TR4ging TR2.R1, R3, R7 l cc in tr suy gim. R18, R13 dng n nh tr khng cho cc phn mch pha saun. L3, C2, C21, C4, C23, L4, C10 l cc linh kin nmtrong c cu mch lc thng thp. L7 Ging L8 ng mch trn. R19//L7 dng n nh trkhng cho L7.

R15 dng trong c cu nh thin cho chn E caTR3. R17 nh thin cho chn E ca TR4. R14 l mtphn ti ca TR3 v cng l in tr ghp gi haitng khuch i TR3 v TR4. RV5 l bin tr iu chnh mc ra S2 OUT mc cn thit. R16 dng cp thin p cho chn B ca TR4. RV6, RV7, RV8dng iu chnh mc nh thin cp cho TR4.C12 chc nng ging nh C6, C11 ging nh C5.

+ ng cp ngun tn hiu +10V:Gm IC2, IC1 - in cm v cc t lc.IC2 lm nhim v n nh in p ngun theo kiub v tham s.IC1-P n nh in p ngun cung cp theo kiutham s.Cun cm L5 chn cao tn.

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C13, C14, C15, C16, C17 l cc t lc ngun.Do st p trn cc phn t linh kin k trn m inp cung cp cho chn C cc

Tranzitor TR1, TR2 ch cn +5V.Q13, Q14, Q15 ly in p t ngun ra cung cp chocc phn mch khc.* ng cp ngun in p -10VC nhim v lc v n nh in p mt chiu -10Vv c suy gim cung cpnh thin cho chn E, chn B ca Tranzitor TR2,

TR1. C18, C19 l cc t lc ngun. LG l cun cm

chn cao tn. R22, R23, R24 l cc in tr suygim. D2 l it zener phn cc ngc dng nnh in p kiu tham s. in p sau khi c lcv n inh c a ti cc bin tr t BNDCNT1-SWDCNT16 iu chnh mc phn p nh thincho chn B ca TR2 v TR4.

II.2.2 Nguyn l hot ng ca ton mch.

Mi lung tn hiu v S1, S2 c cho qua cc intr suy gim ri dn n mi IC khuych i h snh, sau tn hiu khuych i c lc thp bicc t in v in cm 2 tng khuych i

Tranzitor tip tc khuych i tn hiu mi ngny vi s iu chnh nh thin cho cc Tranzitorkhuych i v iu chnh mc ra. Vic cp ngun

cho cc Tranzitor c thc hin bi hai ngun ring r(+10V v -10V). Cc ngun ny c lc rt cn thn bi nhiut lc ngun v c n nh bi cc IC hoc Diotzener. Ngoi vic cung cp in p cho cc phn ttch cc trong s ny hot ng, n cn cung cpngun cho cc phn mch khc u ra Q13, Q14,Q15.

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II.3 Khi iu ch (MOD)II.3.1 S nguyn l khi iu ch (MOD).

II.3.2 Tng quan s nguyn l khi MOD.

HYB1 phn tn hiu ra hai ng ring r:+ ng 1 a n hin th tn hiu dao ng nicha iu ch LOF MON.+ ng 2 a n iu ch ti D1 c tn hiura RF OUT.Xt tng ng tn hiu:

ng tn hiu a n tn hiu hin th ti LOFMON:

T b sai ng HYB1, tn hiu b suy gim mt phnri c khuch i ln nh IC1. Tn hiu ra t sauIC1 li b suy gim mt phn trc khi a n ura hin th. C1 ngn cch mt chiu gia khi MOD vcc khi bn ngoi. C2, C32, C3: L cc t ni tng vngn cch mt chiu. C15, C13, C12: L cc t lc

ngun v chng in dung tn s cao cho mch.R1, R2, R3 lm thnh mt b gim tnh. R4, R5: Nimt chn ca b sai ng HYB1 xung t.(R6, R7, R8) v (R9, R10, R11) lm thnh cc b suygim tnh.+ ng tn hiu a n iu ch:

Ta c th chia ng tn hiu ny thnh ba phnmch:

- Phn mch khuych i trc khi iu ch:Gm cc Tranzitor TR1, TR2 v cc linh kin c linquan. Phn iu ch vihai ng tn hiu cao tn v hai ng tn hiuvo S1, S2: Khi D1.- Phn mch khuych i sau iu ch:Gm cc Tranzitor TR3 v TR4 v cc linh kin c linquan.

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- Phn mch khuych i RF trc khi a vo iuch:

TR1 l mt Tranzitor loi P c mc E chung lm

nhim v khuych i s b tn hiu siu cao tnly t b to dao ng sau khi a qua b HYB1. C4,C5: L cc t ni tng, C16 l t lc ngun. C8, C9: Lcc t phi hp tr khng vo v ra cho TR1. C14 l tlc ngun. C6, C7 l cc t ni tng. TR2 cng gingnh TR1 v cu to cch u ni.R17, R16, R15 l cc in tr phn p cung cp nhthin cho chn E v chn C ca Tranzitor ca TR2.

C10, C11: C chc nng nh cc t C8, C9. Tn hiu tiu ra ca TR2 b suy gim mt phn ri c tchlm hai a vo iu ch.R18, R19, R20: Lm thnh mt b suy gim tnh. R21,R22 l cc in tr ni t ca b phn ng dchpha (90o). (R23, R24, R25) v (R18, R19, R20) cnglm thnh cc b suy gim tnh.C17, C18 l cc t ni tng.

- Phn mch khuych i sau khi iu ch:TR3 l Tranzitor ngc mc E chung lm chc nngkhuych i.R31, R32, R33 lm thnh b suy gim tnh. R36, R35,R34: L cc in tr cung cp nh thin cho TR3hot ng.C21, C22 l cc t ni tng, C30 l t lc ngun cungcp. C25, C26: C chc nng ging nh C10, C11. TR4

ging nh TR3 lm chc nng khuch i tn hiu tu ra ca TR3, do n phi lm vic ch dng p lc. Kt cu mch in ca h hon tontng t.C23, C24, C31 l cc t ni tng. C29 l t lc. C27,C28 c chc nng ging nh C10, C11. R39, R38, R37l cc in tr phn p nh thin cho TR4, (R40,R41, R42) lm thnh b suy gim tnh.

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- Phn iu ch:Phng thc iu ch c dng y l 4-QAM(iu ch theo kiu iu bin cu phng). Hai

lung tn hiu vo S1, S2 di dng m NRZ sau khi c x l pht ti TDP, qua cc b lc thng thphnh G c a n cu phng ti D1 cng vihai lung tn hiu siu cao tn nhn c t OSC saukhuch i D1, hai dng tn hiu ny c trn li iu ch theo kiu i tn trn. (R29, C19) v(R30, C20) l cc b lc thng thp hnh G i vi hailung tn hiu S1 v S2.


Tn hiu siu cao tn do b OSC to ra c avo b MOD nh jc cm S1, sau b suy gim mt phn trc khi n b sai ngHYB1. Ti y n c phn thnhhai ng ring r:

+ ng 1: c khuch i trc khi a vo iuch ti D1.+ ng 2: V phng thc iu ch y liu bin cu phng 4-QAM nn cn mt b di phaphn ng tn hiu t u ra TR2 thnh haing c pha vung gc a vo iu ch cnghai ng tn hiu S1 v S2 mc tn hiu iu ch u ra l D1 l kh nh nn cn phi c khuch

i ln cho ln trc khi a n u ra RF OUT.Chc nng khuych i ny do hai Tranzitor TR3, TR4m nhn. Mc tn hiu tiRF OUT khong -5dBm, mun pht i n phi ckhuych i ln n khong +33dBm nh bkhuych i cng sut siu cao tn HPA.Ngun in cung cp cho khi MOD l cc mc +10Vv -10V.

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II.4 Khi khuch i cng sut siu cao tn

(HPA).II.4.1 Tng quan s nguyn l khi HPA.

Nm b sai ng HYB1HYB5: Lm nhim v phnmt ng tn hiu ra lm hai ng hoc gp haing lm mt, tuy nhin vn c b sai ng chn thun bin mt ng ny sang mt ngkhc nh b HYB1 (bin p). Ba tng khuych i

n dng 1 Tranzitor trng loi JFET gm TR1, TR2,TR5. Hai tng khuych i i vi 2 Tranzitor trngcng loi JFET gm (TR3, TR4) v (TR6, TR7). tin cho vic phn tch chi tit vo mch in taphn tch mch in trn thnh 5 phn c bn sauy: Phn mch khuch i n th 1: Bao gm b saing HYB1, Tranzitor

TR1 v cc mch c lin quan. Phn mch khuch i n th 2: Bao gm

Tranzitor TR2 v cc mchc lin quan

Phn khuch i i th 1: Bao gm b sai ngHYB2, cc Tranzitor TR3, TR4. Phn mch khuch i n th 3: Bao gm b saing HYB3 v TR5.

Phn mch khuch i i th 2: bao gm 2 b saing HYb4 v HYB5, 2 Tranziot trng TR6, TR7 phnca ra ca mch v cc linh kin c lin quan.

a. Phn tch s nguyn l ca tng mch.

+Phn khuch i n th 1 (tng 1):B sai ng HYB1 ch n thun bin mt ng

tn hiu vo thnh mt ng tn hiu ra v phi

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hp, tc l n ng vai tr nh mt bin p thngthng. Cc iot D2, D1 ni chn bin p xung t.R41, R42, R43 lm thnh b suy gim tnh, R34 l

in tr suy gim mt phn in p ra iu chnh.C1 ngn cch mt chiu gia tn hiu vo v bHYB1, C71: L t lc ly in p mt chiu bngphng ALC CONT, C34, C15, C16 l cc t chng ksinh tn s cao trong mch.

Tng khuych i TR1 lm nhin v khuych i sb tn hiu vo, y ta dng cc Tranzitor trngcho khuych i vi mc ch phi hp tr khng tt

cho cc tng. TR1 c mc theo s cc ngunchung, c phn cc theo kiu mch c nh dngphn t tch cc TR11. S phn cc ny m borng thin p cung cp cho TR1 lm vic lun lunkhng i. V TR1 c cc ngun ni t, in pcung cp cho cc Dca n c ly t cc E ca TR11 v cho cc G ly tcc C tng ng.

C2, C3 l cc t ni tng. C72, C73 l cc t ngun.C51 l t xoay chiu. C17, C18, C201, C202 l cc tchng in dung k sinh tn s cao trong mch. D4,D5 cc it zener dng n nh in p nguncung cp.R75, R79, R71, R91, R51, R52, R63 l cc in trphn p cho TR1. R1 l intr cp ngun cho TR1. (R2, C52) chng in dung k

sinh tn s thp.+ Phn mch khuych i n th 2 (tng 2):

Tng khuych i TR2 lm nhim v khuych i tnhiu ra sau tng khuych i TR1. Tng t TR1, TR2cng l cc Tranzitor trng JFET loi N c mctheo s S chung, c phn cc theo kiu mchc nh dng phn t tch cc TR12. S phn cckiu ny cng s m bo thin p cung cp cho TR2

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lun l khng i. Nguyn tc n nh ca TR2lun l khng i, s mc mch ca n honton nh TR11 n nh cho TR1. C4 l t ni tng,

ngn cch TR2 v b sai ng HYB1. C74, C75 l cct lc ngun. C53 l t lc xoay chiu. C19, C20 l cct lc chng k sinh tn s thp. D4, D5 l cc itzener lm chc nng n nh.R76, R80, R92, R54, R56, R64 l cc in tr phn pcho TR12. R3 l in tr cp ngun cho TR2. R94 lin tr suy gim trn ng cp ngun mt chiun cc G ca TR2. (R4, C54) lm chc nng chng k

sinh in dung k sinh tn s thp.+ Phn mch khuch i i th 1 (tng 3):

B sai ng HYB2 lm nhim v bin i t mtng tn hiu ra thnh 2 ng tip tkhuych i trong c cu khuych i i. y tadng khuych i i bi v ta cn mt cng sut ln,song cng sut chu ng ca Tranzitor trng dngtrong mch l hn ch, nn dng hai ng khuych

i sau cng li bi b sai ng c mt cngsut ln gp i. R36, R37 l cc in tr ni t cab sai ng.Hai ng khuych i ny hon ton nh nhau cv s kt cu, chc nng v c thm ch c gitr cc linh kin.* ng 1: TR3 cng l mt Tranzitor trng gingnh TR2 v TR1, lm chc nng khuch i, c

nh thin theo kiu tch cc bi TR13. Nguyn tcnh thin n nh in p cung cp ny hon tontng t nh TR1 nh thin cho TR1 v TR2 nhthincho TR2. Tc dng ca cc linh kin:C5, C7 l cc t ni tng ngn cch mt chiu. C21,C32, C221, C222, C225 l cc t chng in dung k

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sinh tn s cao trong mch. C76, C78 l cc t lcngun. C55 l t lc xoay chiu.R77, R81, R93, R73, R57, R58, R59, R65 l cc in

tr phn p nh thin cho TR3. R5 l in tr trnng cp ngun cho TR3 c tc dng suy gim mtphn in p ngun cung cp. D6, D7 l cc diotzener lm chc nng n nh. (R7, R57) lm chcnng chng in k sinh tn s thp trong mch.* ng 2: TR4 hon ton tng t nh TR3 v TR14ging nh TR13 nhnh 1.

Tc dng ca cc linh kin:

C6, C8 l cc t ni tng. C22, C24, C231, C232, C235l cc t in chng k sinh tn s cao. C56 l t lcxoay chiu.+ (R8, C58) lm chc nng chng k sinh tn s thp.+ Phn mch khuych i n th 3 (tng 4):Phn mch ny gm TR5 v cc linh kin c lin quan

TR5 l JFET loi N mc S chung trong cc S cni t, 2 cc G, D c cp in t hai ng ring

r. Chc nng chnh ca TR5 ch l khuch i tnhiu siu cao tn t u ra ca b cng cngsut HYB3 ri a n u vo b sai ng HYB4xung t. Hai ng khuych i nyging ht nhau v s nguyn l v kt cu.* ng 1: c ph trch bi TR6, chc nng chnhca n l khuych i c mt cng sut lnhn.

C11, C13 l cc t ngn cch mt chiu gia TR6 viu vo v u ra. C27, C29, C251, C255, C256 lcc t hn ch in k sinh tn s cao. C82, C84 lcc t lc ngun. R11, R102 l cc in tr cp nguncho TR6 lm vic. R22 l in tr n nh tr khngvo cho TR6.(R13, R63) lm nhim v chng in dung k sinhtn s thp.

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* ng 2: Do TR7 ph trch c chc nng ging htTR6 nu trn.D10, D11 l cc diot zener dng n nh in p

mt chiu ngun cung cp. C83, C85 l cc t lcngun, C12, C14 l cc t ni tng. C28, C30, C261,C265, C266 l cc t hn ch in dung k sinh tn scao.R103, R23 l cc in tr cp ngun cho TR7 lmvic. R23 dng n nh tr khng vo cho TR7.(R14, R64) dng chng in dung k sinh tn sthp. HYB5 lm nhim v cng cng sut t 2 ng

trn mt ng a n ca ra. Ti ca ra c mtng tn hiu siu cao tn ti y chnh lu, lcv a ra chn s 1 ca CD1 di dng in p mtchiu, y l tn hiu pht ra mc cng sut pht.R50 tng t nh R40. R15, R16 l cc in tr nit ca mch ca ra. R45, R44, R46 l cc in trsuy gim mc cng sut pht v n nh tr khngca ng mch ny. R31, R32: Suy gim tn hiu

mt chiu sau lc. D3 l it chnh lu. C31, C32,C33: L cc t lc sau chnh lu. RF MON: Ca ra lytn hiu o v hin th.RF OUT: Ca ra ly tn hiu sau khuch i a raAnten.


Tn hiu siu cao tn RF IN (t b MOD) vo qua lcm J1, qua b suy gim tnh c ghp qua mtng khc a n hai tng khuych i n.

Tn hiu u vo v u ra b HYB1 c an chn s 2 ca CD1 iu chnh mc vomt cch t ng. Qua 2 tng khuych i n TR1v TR2 tn hiu c phn lm hai ng nh b

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sai ng HYB2, mi ng c khuych i ring rnh TR3 hoc TR4. Sau cng cng sut ckhuych i mi ng nh HYB3 c mt

cng sut ln gp i. Cng sut ny tip tc cTR5 khuych i, sau tn hiu t u ra ca TR5 lic tip tc khuych i nh ln trc ri HYB5thc hin chc nng cng cng sut thai ng li c mt cng sut siu cao tn ln thng qua mch ca ra v phn nhnh ti RF OUTv RF MON. Mc cng sut ra RF OUT c xc nhnh mch TLVL DET.

Ngi ta cng trch mt phn tn hiu ra chnh lulc thnh in p mt chiu, thng qua cc in trsuy gim a n chn 1 ca CD1 xem xtmc cng sut pht ra.

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