Tối ưu hoá quá trình truyền năng lượng tín hiệu và nâng cao độ nhạy của các thiết bị thu dải tần số cao có chọn lọc

"^ Tren ca sa phan tfch cac toan tir trong khong gian nang lugng trang thai tfn hieu da thiet lap dugc bieu thuc ciia he so truyen dat cong suat cua mang 4 cue du6i dang cac cap ham ma t

DAI HOC QUOC GIA HA NOI TRl/dNG DAI HOC KHOA HOC TlT NHIEN

£)ETAI

TOI UU QUA TRINH TRUYEN NANG LUONG TIN HIEU

VA NANG CAO DO NHAY CUA CAC THIET BI THU

DAI TAN SO CAO CO CHON LOC

MASO:QT-05-11

CHU TRI DE TAI: VU THANH THAI

(KHOA VAT LY)

HA NOI - 2005

DAI HOC QUOC GIA HA NOI TRUCJNG DAI HOC KHOA HOC TIT NHIEN

€)ETAI

TOI UtJ QUA TRINH TRUYEN NANG LUONG TIN HIEU

VA NANG CAO DO NHAY CUA CAC THIET BI THU

DAI TAN SO CAO CO CHON LOC

MA SO: QT-05-11

CHU TRI DE TAI:

CAC CAN BO THAM GIA:

THS GVC VU THANH THAI GPS-TS VU ANH PHI

1 BAO CAO TOM TAT

a Ten de tai:

Toi icu qud trinh truyen ndng luang tin hieu vd ndng cao do nhay ciia cdc thiet bi thu ddi tdn so cao co chgn Igc

(Ma so: QT-05-11)

b Chu tri de tai: ThS Vu Thanh Thai

c Cac can bo tham gia: POSTS VQ Anh Phi

Ths Dang Thi Thanh Thuy

d Muc tieu va noi dung nghien cuu:

- Xay dung bai toan toi uu truyen nang luong trong khong gian song cao tan

- Tdng hgfp cac mach phoi hgfp va toi uu hoa dac tfnh truyen dat cong suat cua he thdng thu va xu li tin hieu

- Tfnh toan va dua ra giai phap nang cao do nhay ciia thiet bi thu tan so cao co chon loc

e Cac ket qua dat dugc :

• Kit qud nghien cAu khoa hgc:

* Dua tren ly thuyet v6 khong gian tuyen tfnh gia Ocht (Mincopski) da xay dung dugc mo hinh vat ly thuc cua khong gian tuyen tfnh - khong gian nang lugng trang thai tfn hieu

"^ Tren ca sa phan tfch cac toan tir trong khong gian nang lugng trang thai tfn hieu da thiet lap dugc bieu thuc ciia he so truyen dat cong suat cua mang 4 cue du6i dang cac cap ham

ma tran vo huang ciia cac dang toan phuang chi cua mot bien Dieu nay cho phep dua bai toan xay dung he thong truyen tfn hieu voi dac tfnh truyen cong suat cue dai ve bai toan gia tri rieng ciia dang toan phuang trong khong gian nang lugng ciia trang thai tin hieu

* Xay dimg bai toan truyen song cao tan trong khong gian :

da tfnh toan thanh cong van d6 toi uu nang lugng cho song cao tan qua cac dac trung cua song tai va song phan xa

* Tong hgp cac mach phoi hgp; tinh toan toi uu hoa dac tfnh truyen dat cong suat ciia song sieu cao tan Bang ly thuyet da chi ra r^ng chi can sir dung cac mach phoi hgp 3 phan tii co thd phoi hgp dugc vcd cac phan tu M4C hoac M2C bat ky va co the thay doi dac tuyen phoi hgp ciia he thong b^ng each thay ddi cac tham so vat ly ciia mach phoi hgp ma khong thay ddi thiet ke ciia no

* Tfnh toan mot so mach cu the truyen song sieu cao tan va dua ra cac thong so toi uu cho mach phoi hgp de dat cong sua't truyen cue dai Khao sat dac trung truyen nang lugng ciia mach sieu cao tan

• Ket qud dao tao:

*- Co 02 khoa lu|n tot nghiep dai hgc da dugc bao ve theo hu6ng nghien cun ciia de tai

*- Khoa luan nam hgc 2005-2006 se co 2 sinh vien nghien cuu tiep tuc theo huang de t a i

f Tinh hinh kinh phi cua de tai:

Tdng kinh phf thuc chi : lO.OOO.OOOd Trong do - Tir ngan sach nha nu6c : Od

- Kinh phf ciia DHQG : lO.OOO.OOOd

- Vay tfn dung : Od

- Von tu CO : Od

KHOA QUAN LY

(Ky va ghi ro ho ten)

CHU TRI DE TAI (Ky va ghi ro ho ten)

TRI DE TAI OHIEUTHUOKU

^j^.Twk^f ^ik

2 BRIEF REPORT OF PROJECT

a Project title:

Optimize of transmission energy of signal and to raise the sensitivity of the receivers high-frequency selectively

(Code: QT-05-11)

b Project co-ordinator: MSc Vu Thanh Thai

c Co-operator Pro Dr Vu Anh Phi

MSc Dang Thi Thanh Thuy

d Objectives and scientific contents:

- To solve a optimal problem of transmission energy in the

space high-frequency waves

- To synthetize the coordinate's circuits and optimize a partycuarity transmission power of receivers and signal processing

- To calculate and to put foward method to raise the sensitivity of the receivers high-frequency selectively

e Results :

• Science results:

* Based on the theoretical of the linear space- Euclit's false ( Mincopski's space ) , we constructed real physics model of linear space This is the energy space of signal state

* We established the expressions of transmission power coefficient of a four-pole network (M4C) to expressin the form a pair supecalar matrix function of quadratics of the only variable For this reason , we came to conclusions that the solution of the combined problem on the linear system for signal transmission will become the solution of problem on specific values in quadratic form in the linear space - energy space of signal state

* We solved a problem of the transmission high frequency waves in the space ; To solved a problem optimize of energy of the high frequency waves in the form values of incident and reflected waves

* The authors calculated some of concrete circuit -super high frequency and disgnated parameters for to obtain a maximium power « •» v:

• Training results:

There are 02 graduation theses having been defended from the project's goal In the next year , will be 02 graduation

continues

PHAN CHINH BAO CAO

1 MUC LUC

Bao cao tom tit 1 Brief report of project 3 Phan chfnh bao cao 4

truyen dat cong suat ciia he thong thu va xir If tfn hieu S

3.3 Tfnh toan va dua ra giai phap nang cao do nhay ciia

thiet bi thu tan so cao co chgn Igc i§

4 Ket luan J.5

5 Tai heu tham khao J|3

2, LCil MO DAU

Trong kl thuat viln thong , mot trong nhirng chi tieu ki thuat ca ban

khi xay dung he thong thu va xir If tfn hieu la viec dam bao he sd truyen

tai cong suat tac dung cam iing vao anten thu tod phu tai dat gia tri 16n

nhat Nang cao he sd truyen cong suat se lam tang chat lugng va cir ly

thong tin ( khi cong suat phat cung nhu cau true he thdng anten khong

thay ddi) Giai quyet nhiem vu dat ra din tdi viec giai bai toan phdi hgp

giira cac khdi chiic nang ciia may thu , dac biet la tuyen sieu cao tan

Ngay nay, vdi nhiJng tien bg nhay vgt ciia ky thuat mdri va c6ng

nghe che tao cac linh kien dien tu, hang loat linh kien mdi dugc dua vao

sii* dung Viec su dung cac linh kien mdi nhu cac ph& ttr td hop cao, cic

linh kien lam viec d giai song sieu cao tan cang can phai doi hoi ngJu^

cuu cac thuat toan tdi uu de phdi hgp chiing

De tai nay la tiep ndi ciia de tai " Tdi iru hoa qua trinh truyoi nafl^

lugng tfn hieu dien trong mach dien tuyen tfnh va trong khdng gia" "• ^

sd : TN 03-05 cung do chinh nhdm tac gia nay thirc hien

Ket qua ciia de tai ma sd TN 03-05 da dat Auoc Ja:

1 Xay dung mot mo hinh vat ly thirc cua khong g^an'WF^^^ |

sang giai bai toan ve tri ridng, vec ta rieng trong khong gian gia Oclit (khOng gian mincopski)

2 Vdi mo hinh tren chiing toi da xay dung va giai bai toan match dien voi cac thong sd la U, I cua dong dien Dua bai toan cong suat cue dai ve viec quay vecta khong gian

3 Tfnh toan cho mot sd mach phdi hgp 3 phin tu

De tai QT-05-11 nay se giai quyet tiep nhOtig van de sau :

1 Xay dung bai toan truyen nang lugng tdi uu trong khong gian song cao tan

2 Tdng hgp cac mach phdi hgp , nang cao cong suat thu ciia he thdng thu va xir li tfn hieu

3 Tfnh toan va dua ra giai phap nang cao do nhay cho cac thiet bi thu tin sd cao cd chon loc

3 NOI DUNG CHINH 3.1 Xay dung bai toan truyen nang lugng tdi uu trong khong

gian song cao tan

3.1.1, Cdc todn tu: truyen dat trong khong gian song cao tdn

Trong dai sdng sieu cao tan , khi giai bai toan truyen tfn hieu cQng nhu bai toan ly thuyet mach , ngu6i ta diing cac tham sd sdng: sdng tai va song phan xa thay cho cac tham sd dien ap va dong dien Trong truang hgp nay , dac tfnh ciia cac M2C va M4C cung dugc dac trung bdi cac tham sd sdng : Mang 2 cue dugc dac trung bdi he sd phan xa M4C dac trung bdi ma tran tan xa S va ma tran truyen dat T

Tdng quat, quan he giua dien ap U^, dong dien I^ vai sdng tai va sdng phan xa tren cac cue ciia MnC dugc xac dinh :

U = a + b

I - a - b Trong dd: b=ap

p = — - : la he sd phan xa ciia M2C

z + p * z: Tdng trd ciia M2C p: Trd khang song ciia doan day ndi vdi M2C Neu ta ggi khong gian sdng ciia trang thai tfn hieu ciia M4C bao gdm cac vecta: C^ = ae^ + be^ (1)

Trong dd €3,6^ la vecta ca sd khong gian sdng trang thai tfn hieu,

thi dt dang thay ring, khong gian sdng (1) va khong gian kinh dien

v^ = ue, +ie2 la dang cau, va ma tran chuyen T tir ca sd (€,,62) sang ca sd (€3,6^) CO cau true:

^1 I

Trong khong gian sdng trang thai tfn hieu, cong suat tac dung ciia M2C, hay binh phuang do dai vecta trang thai tfn hieu dugc xac dinh bdi bieu thiic:

Hinh 2

Tir hinh ve, dt thay ring: gia tri khong doi cua cong suat tac dung

ciia M2C cd the nhan dugc v6i cac gia tri khac nhau ciia cac toa do a, b Han the nua, cac toa do a, b lien he v6i nhau bdi bieu thiic (3) TCr sir phu thuoc giua cac toa do a, b co the tha'y ring, viec chuyen tir toa do nay sang toa do khac cd the dugc thuc hien bing viec quay dudng hypecbol mot gdc 9 nao dd, ma viec quay dd hoan toan khong lam thay ddi do dai vecta

3.1.2 Gidi bdi todn cong sudt cue dai:

Neu mang 2 cue da cho dugc ndi vdi M4C tuyen tfnh vdi ma tran sdng T Thiet lap mdi lien he giira song tai va sdng phan xa tren dau vao

va dau ra ciia M4C (hinh 3)

la ma tran truyen sdng ciia M4C

thi ta se nhan dugc M2C mdi vdi he sd phan xa P,

Dac tfnh ciia M2C mdi dugc dac tnmg bdi cac bien mdi aj, bj Cac bien aj, bi lai dugc xem nhu la toa do ciia vecta C, cung trong khong gian

nang lugng trang thai tfn hieu Va trong trudng hgp nay, ma tran truyen sdng T cia M4C dugc xem nhu toarftir tuyen tfnh trong khong gian sdng

2 chilu, thi6't l|p mdi quan ht giiia cac vecta trang thai tfn hieu tren diu

vao va dau ra ciia M4C

Trong khong gian sdng trang thai tfn hieu, cong suat tac dung len diu vao va diu ra ciia M4C dugc xac dinh bdi hieu cua cong suat sdng tdfi

va cong suit sdng phan xa

Ddi vdi cac M4C tuyen tfnh tich cue, khong tdn hao, co tdn hao, cong suit tac dung tren diu vao P, tuang iing se nhd han, bing, lan han cong suat tac dung tren diu ra Pj ciia nd Nghia la, toan tir T co the la toan tii gian, Unitar, toan tii co Tren quan diem toan hgc, ma tran truyen sdng

T CLia M4C khong tdn hao thuc hien phep bien ddi toa do ciia vecta trong khong gian sdng nang lugng trang thai tfn hieu, nhung khong lam thay ddi do dai ciia vecta Cdn trong ky thuat thu va truyen tfn hieu, cac M4C khong tdn hao dugc diing de phdi hgp cac phan tii (cac khdi chiic nang) ciia he, dam bao he sd truyen tai cong suit tir ngudn tfn hieu tdi phu tai dat gia tri Idn va de chgn Igc tfn hieu theo phd tin cua nd

Phil hgp v6i cac bi^u thiic (10) -H (13), he sd truyen cong suat ciia mang 4 cue cung dugc viet dudi dang bieu thiic ciia cac dang toan phuang

ciia cimg mot bien ma tran C, hoac C2:

P2 C2^JC2 C ; ( T J T - ) - ' C ,

Pi C2^(T-'JT)C2 Ci^JC,

Bieu thiic (14) cho phep dua viec giai bai toan xay dung he thdng tuyen tfnh truyin tfn hieu vdi dac tfnh truyen dat tdi uu ve viec giai bai toan tri rieng ciia cac dang toan phuang trong khong gian sdng nang lugng trang thai tfn hieu va phan loai cac M4C theo dac tfnh nang lugng ciia nd

5.i.3 Mot so kei ludn:

Vdi cac k^t qua nh$n dugc cd the dua ra mot sd ket luan sau day:

1 Khong gian nang lugng trang thai tfn hi6u cua mach dien tuyen

tfnh la mo hinh vki ly thuc cua khong gian tuyen tfnh Ddi vai M2C thu

dgng, khong gian nang lugng trang thai tfn hieu la khong gian tuyen tfnh vdi me-tric hypecbol Trong khong gian binh phuong do dai vecta xac dinh cong suit tac dung dugc biic xa hoac hap thu cua M2C Mdi tuang quan nay cd y nghia quan trgng trong thuc te xay dung he thdng truyen tfn hieu, vi nd cho phep thiet lap mdi lien he giua viec quay vecta trong khong gian vai viec bien doi cac mang 2 cue bing cac mang 4 cue khong tdn hao ma vin dam bao dac tfnh biic xa, hoac hip thu nang lugng ciia nd

2 Tir viec phan tfch cac toan tir tuyen tfnh trong khong gian nang lugng trang thai tfn hieu da thiet lap mdi lien he giira viec bien ddi cac vecta bao toan do dai cua nd vai viec bien ddi cac M2C nhd cac M4C tuyen tfnh khong tdn hao, va do do co the coi ma tran truyen dat ciia cac M4C khong tdn hao nhu la ma tran ciia phep bien ddi tuyen tfnh khong lam thay ddi do dai vecta

3 Tren ca sd phan tfch cac toan tir trong khong gian nang lugng trang thai tin hieu da thiet lap dugc bieu thiic ciia he sd truyen dat cong suit ciia M2C dudi dang cac cap ham ma tran vo hu6ng cua dang toan phuang chi ciia 1 bien sd Di6u dd cho phep dua viec giai bai toan xay

dung he thdng truyen tfn hieu vdi dac tfnh truyen dat cong suat cue dai ve

bai toan tri rieng ciia dang toan phuang trong khong gian nang lugng trang thai tfn hieu Dieu nay co y nghia thuc te Idn trong linh vuc dien tir viSn thong,

3.2 Tong hgp cac mach phdi hgp va tdi uu dac tinh truyen dat

cong suat ciia he thdng thu va xir ly tin hieu

3.2.1 Bdi todn cong sudt cue dai:

Trong kl thuat vi6n thong , khi xay dung he thong thu va xir If tfn hieu phai dam bao dugc he ssd truyin cong suit cue dai Dieu nay cd y ngliTa rat Idn la : trong khi cong suit phat va cau true ciia he thdng anten khong thay ddi , neu ta nang dugc cong suit thu se lam tang chat lugng va tang cu ly thong tin Trong ki thuat rada , nang cao he sd truyen cong suit se lam tang cu ly phat hien muc tieu , ddng thdi cung tang kha nang phat hien muc tieu cd dien tfch phan xa nhd

Giai bai toan cong suit cue dai nay ciia may thu cao tin din den bai toan phdi hgp giira cac khdi chiic nang ( hoac cac phin tir chiic nang ) ciia tuyen sieu cao tin ciia may thu

De sang td dieu nay , ta xet mot bai toan dan gian :

Xet viec truyen cong suit tac dung til ngudn tfn hieu cd tdng trd trong ZQ = Ro + JXQ den phu tai Zt = Rt + jX^ ( X e m hinh 4 )

-Thay gia tri ciia I tir (16) vao (15) ta cd :

E^R, (Ro+Rt)'+(Xo+X,)^

E^R (Ro + Rt)'

(19)

Dao ham bieu thiic (19) theo R, va cho dao ham triet tieu , ta se tim dugc dieu kien , khi dd cong suit tac dung truyen tir ngudn tfn hieu den phu tai dat gia tri cue d a i Dd chfnh la :

RpRo (20) Khi dd cong suit cue dai tren phu tai la :

P=P =

^ t ^ t max 4Ro (21) Ket hgp dilu kien (18) vdi dilu kien (20), ta cd ;

P =P

*^t ' t l z,-z, 4R (22)

Trong thuc te , khi xay dung he thdng thu va xir ly tfn hieu , dilu kien Z, = Z* thudng khong dugc thuc hien , nen ngudi ta phai dung cac mach (thudng la cac mach khong tdn hao ) mic giua ngudn tfn hieu va phu tai (hinh 5 )

Hinh 5 Cac mach dien nay lam chii:c nang bien ddi tdng trd phu tai thanh tdng trd cd gia tri mong mudn dam bao cong suit tac dung len phu tai dat cue dai Chiing dugc ggi la cac M4C phdi hgp

Cdn vl mat toan hgc , nhu tfnh toan ly thuyet da chi ra d tren : viec mic cac phin tir phdi hgp ding tri vdi cac phep bien ddi tuyen tfnh trong khong gian nang lugng trang thai tin hieu , khong lam thay ddi do dai vec

ta

3.2.2 Mo hinh tong qudt cua he thong thu vd xii ly tin hieu

He thdng thu va xir ly tin hieu n kenh bat ky dugc mo ta bing mo hinh tdng quat (hinh 6 )

Hinh 6 Trong dd cac mang nhilu cue loai phan xa S^ dac trung cho khdi ngudn tfn hieu ; St dac trung cho khdi phu tai ,c6n cac MnC loai true thong Si,S2, Sn dac trung cho cac khdi chiic nang ciia he thdng (phan kenh, khuech dai )

Ddi vci he thu va xir ly mot kenh ( he thdng dang dugc sir dung rong rai) dd la cac M2C va M4C nhu hinh 7

1 Bai toan phdi hgp giira cac M2C

2 Bai toan phdi hgp giira M2C va M4C

3 Bai toan phdi hgp giiia cac M4C vdi nhau Xet M4C tuyen tfnh bit ki dugc dac tnmg bing ma tran truyin sdng IT] nhu hinh 8 Diu vao va diu ra ciia M4C dugc ndi v6i ngudn tfn hieu

va p hu tai vdi he sd phan xa phiic P^ va P^ tuang iing

Kp=JTJT (25) Ka=TJrj (26)

Dl dang thay ring , cac ma tran J , T^JT , TJT^ la cac ma tran

Hecmit , do dd cac tri rieng Xi {\Xi) cua ma tran dac trung Kp (K^) la sd thuc Mot trong cac gia tri dd X\ ([i\) xac dinh he sd truyin cue dai cua

M4C cd the dat dugc khi truyin tfn hieu theo chilu thuan , gia tri cdn lai

^2(1^2) - khi truyin theo chilu ngugc lai

Ivr-Co the chiing minh dugfc ring gia tri truyen dat cong suat cue dai cua M4C la khong doi , doi voi cac bien doi khong ton hao Thuc vay , gia sir trfin dSu vao va dau ra cua mang 4 cue T duoc mdc hen thong voi cac mang 4 cue khdng ton hao Ta, Tp voi cac ma trSn truyen song [Ta] , [Tp] (xem hinh 9) Khi nay , doi v6i he thong truyen tin hieu nay , ma tran dac trung se co dang :

K„ =TJT*J

Kp=JT-'JT

Hinh 9 (27) (28)

VI y nghia vat If, dilu nay cd nghia la khi thiet lap cac mach phdi hgp khong tdn hao vai diu vao va diu ra ciia M4C thi dac tfnh truyin tai cong suit tac dung cue dai ciia M4C la khong thay ddi; nhung nd cho phep phdi hgp dugc M4C theo ca diu vao va diu ra M4C khong ton hao chfnh la nhung bg bien ddi tdng trd If tudng , bg quay pha If tudng

13

B6 bien doi tong trd li tudng lam thay ddi mdi tuang quan giira sdng tdi va sdng phan xa, nhung khong lam thay ddi do dai vecta, do dd

nd xac dinh dugc dilu kien phdi hgp giira ngudn va tai, ciing nhu giira cac M2C va M4C Nhu vay he thdng xir ly tfn hieu ed dac trung truyin dat cue dai hoac dac tfnh tap tdi uu

Cac bg quay pha If tudng khong lam thay ddi tuang quan sdng tdi

va sdng phan xa Nghia la khong lam thay ddi ti sd U,hAJ,ap diing de xay dung he thu va xir ly tfn hieu vdi dac tfnh chgn Igc tdi uu

3.2.3 Tinh tri rieng vd vec ta rieng cho M4C khong ton hao

Viec tfnh toan cac tham sd ciia M4C khong ton hao (de dat cong suit truyin dat cue dai) din tdi viec tfnh cac tri rieng va cac ham rieng ciia ma tran truyin sdng , ma tran tan xa

Trong he thdng thu tfn hieu (hinh 9) ta thay the cac M2C ngudn va phu tai bing viec ndi giira ngudn va phu tai v6i cac M4C khong tdn hao

cd cac ma tran tan xa [S„] , [SJ hoac cac ma tran truyin sdngCT^] , [TJ ta dugc he thdng nhu ( hinh 10 )

P P2 Hinh 10

Ta cd cac ma tran tan xa [S^] va [S,] da dugc tfnh nhu sau :

Tiir ly thuyet cua phep bien ddi tuyen tfnh , vec ta C20 =[b20'0r (hinh 10) cd thi dugc xem nhu vec ta rieng iing v6i gia tri rieng ^1 ciia phep bien ddi tuyen tfnh x vdi ma tran bien ddi Kp (25) , khi mang 4 cue

da dugc phdi hgp theo diu vao

Tuang tu , vec ta Cjo =[o,b|of (hinh 10 ) cd the xem nhu vec ta rieng iing v6i gia tri rieng Hi ciia phep bien ddi tuyen tfnh U vdi ma tran bien ddi K;' = (TJT''J)"' khi mang 4 cue da dugc phdi hgp theo diu ra , Mat khac , td hgp cac ddng toa do ciia tat ca cac vec ta rieng ciia phep bien ddi tuyen tfnh U v6i ma tran bien ddi A , tuang iing vdfi gia tri

rieng l^ triing vdi td hgp cac nghiem khac khong ciia he phuang trinh

tuyen tfnh tren ; nen cd the viet:

(40), Cj (41) thay vao cac bieu thiic (38), (39) va thuc hien mot vai bien

ddi, ta nhan duac :

15

(Kjjp -A,i) + K,2pPto - 0 K21P + (K22P + ^i )Pto - 0

3.2.4 Mot so kei luan :

1 Dac tfnh truyin dat cong suit cue dai cua M4C tuyen tfnh bit ki

la khong thay ddi ddi vdi cac bien ddi khong tdn hao Cac gia tri rieng ciia cac ma tran dac trung M4C chfnh la gia tri cue dai cua he sd truyin cong suit cua he thdng thu tfn hieu

2 Cac phan tii ciia ma tran truyin sdng ciia cac mach phdi hgp tren diu vao va diu ra cua M4C dugc xac dinh nhu ddng toa do ciia cac vec ta rieng iing v6i cac gia tri rieng ciia cac ma tran dac trung cua M4C

3 Tren quan diem toan hgc , viec thiet lap cac mach phdi hgp tren diu vao va diu ra ciia M4C ( hinh 9) tuang iing vai viec dua cac dang toan phuang (23), (24) ve true chfnh

3.3 Mot sd tinh toan va giai phap nang cao do nhay thiet bi thu

tan sd cao,

3.3.1 Tinh cho 1 modun co SF7900 :

Xet mang 4 cue la modun khuech dai trasistor trudng cao tin SF7900 , tai tin sd 2Ghz Ma tran tan xa cd ket cau :

Dua vao mdi h^n he giua ma tran tan xa va ma tran truyin sdng cua

M4C , ta xac dinh dugc ma tran truyin sdng T cua modun transistor

SF7900 ling vdi ma tran tan xa S :

[T] = 0,45662e"-'^^" 0,289406e"J^^" (46) 0,130I369eJ''^" 0,039046^^^'^"

Theo cdng thiic (42) , xac dinh dugc cac gia tri rieng cua ma tran

dac trung M4C:

^,=0,1059 ; >.2=0,014536 (47) Sir dung cong thiic (43) , (44) tfnh dugc cac gia tri ciia he sd phan

xa cua ngudn vdi tai ding tri:

P„o =0,4969eJ^"'" va P^Q =0,69596^'^'" (48) Trong mot tfnh toan khac , phan tfch ciu true ciia M4C bat ki ;

chiing ta cd M4C [T] cd gia tri truyin dat cong suit cue dai tuang duang

vai 3 mang 4 cue [T,], [To] , [T2] nhu hinh 11:

Hinh 11 Trong dd : [TQ] la M4C " hat nhan" xac dinh gia tri truyin tai cong

suit cue dai , con cac M4C [TJ va [T2] xac dinh dieu kien phdi hgp ciia

M4C trong he thdng thu tfn hieu

Cac ma tran truyin sdng tuang iing vdi 3 mang 4 cue nay la :

Nhu vay , vai cac tham sd ciia ma tran [S] biet truac ciia M4C bat

ki , chiing ta cd the tfnh dugc cac tham sd ciia cac M4C phdi hgp dl dat dugc cong suit truyen dat cue dai

3.3.2 Tong hgp cdc mach phoi hgp detoi itii hod cong sudt truyen dat vd tdng do nhay cua he thong thu tin hieu cao tdn

Bai loan dat ra la budc cudi cimg ta phai tfnh dugc cac tham sd vat

ly ciia mach phdi hgp dl dai dugc cong suat cue dai ciui ca he ihdng ihu tin hieu Ve nguyen tic mach phdi hgp cang dan gian cang ft phan lir cang lot Dac biet la vdi dai song sieu cao tan

Trong mot cong trinh khac chung toi da chirng minh dugc rang :

- Khi phdi hgp cac much 3 phan tir ( hinh T hoac hinh 11 } neu

chgn cac tham sd pha cp , \\f khac nhau thi gia tri cac tham sd

vat li ciia mach phdi hgp cung nhu tfnh chat ciia chiing sc khac nhau

- Sir dung cac mach phdi hgp 3 phan tir cho phep thuc hien \ ice tdi uu hoa dac tuyen truyen dat cong suai ciia he thdng trii\cn tfn l-iieu Dieu khien dugc dac tuyen bien do tan sd pha tan sdciia he thdng

- Neu sir dung cac mach phdi hgp 2 phan tir khong the tdi uu hoa dac tuyen truyen dat ciui he thdng Hcyn the nCra cac mach phdi hgp 2 phan lir chi co the sir dung lam mach phdi hgp trong ciic dieu kien xac dinh

Vdi modun khuech dai ciia (3.3.1) chiing ta da tfnh dugc cac tham

Y2„=-jHp-'[sin(Y + (p)-|Pn|sin(Y + G.+(p)] (55)

Z = H[cos(Y + (p) + |Pjcos(y + 9, + ( p ) ] - l (56)

^ H , [ c o s ( a - ( p ) - | P j c o s ( a - e , - ( p ) ] - l

Y

Y:3=-jQ,p"'[sin(v' + M')-|P.|sin(v' + e,+v|;)] (58)

Q[cos(v-vi;)-|P lcos(v-0, - v|y)J-l

Trong do cac gia tri : H , H, Q, Q, ,a y v , v' la cac gia tri diroc

tinh theo cac cong thiic sau day :

Ncii chon mach phoi hop hinh T va chon cac ihani so jiha (p=vj/=90

ta SC xac dinh diroc ;

L.„=2,22.10-^H '2a" C,a=7,32.10-''F ; C,a=l,76.10-^'F ;

C,p=19,85.10-'-F ; ^^=1,26.10'-? ; L2(3=2,67.10-^H Lap trinh cho cac tham sd (p va y cac gia tri khac nhau , tii dd tinh dugc cac gia tri tham sd vat If ciia cac phan tir ciia mach phdi hgp Ta cd bang ket qua sau day :

Bang 1 Mach phdi hgp hinh T

9

V

Mach phdi hgp tren dau vao Mach phdi hgp tren dau ra

Ket cau Giii tri tham sd Ket cau Gia tri tham