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Bi tp ln H thng vin thng
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1. PHN CHIA CNG VIC
STT H V TN CNG VIC GHI CH 1. Nguyn Th Anh - Phn chia cng
vic.
- Lm bi tp l thuyt v vit code m phng
- Vit bo co
Nhm trng
2. Nguyn Trng Bng - Lm bi tp l thuyt - Tm hiu v lp trnh GUI
3. Nguyn Vn Cng - Khng c lin h g vi nhm 4. T Hu Cng - Lm bi tp l
thuyt
- Ln tng cho giao din
5. Nguyn Vn Cng - Test m phng - Tm hiu v lp trnh GUI
2. BI
Tuyn thng tin si quang c c ly thng tin 60km, tc bit Rb= 5 Mbit/s
s dng
m 1B2B vi cng sut pht -20 dBm. Suy hao do mi gic ni (connector)
l
0.5dB. H thng dng si quang a mode vi suy hao trung bnh ca si l
0,25
dB/km. Suy hao mi mi hn l 0,1dB, tuyn c 29 mi hn. Tuyn thng tin
c t
b khuch i vi h s khuch i 30 dB ti im cch u pht 20 km. Bit
gii
hn di thng do tn sc mode l 1 GHz.Km; h s tn sc cht liu dmat =
3.5
ps/nm.km ( bc sng 1550 nm ); rng ph ca ngun quang 80 nm; suy
hao
d phng cho thit b 3 dB; suy hao d phng cho cp 0,1 dB/Km.
a. Tnh cng sut u thu cho tuyn thng tin quang trn.
b. Vi c ly truyn dn trn, di thng c b gii hn khng?
3. LI GII
a, Mi u pht/thu c mt b ni.Mi b khuch i dng 2 b ni. Vy h thng
trn c s b ni l 4. Cng sut u thu cho tuyn thng tin quang trn
l:
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[] = [] [] [] + []
= [] [] [] [] []
[] + []
= -20 0,5.4 0,25.60 29.0,1 3 0,1.60 + 30 = -18,9 [dBm]
b, H thng s dng m 1B2B suy ra k = 2
= = . = 2.5 = 10[] = 0,01[]
tn sc ti a cho php l :
= 1
4. []=
1
4.0,01= 25[]
tn sc mode l:
[] =0,44. []
[. ]=
0,44.60
1= 26,4[]
tn sc mu l:
= + ( => )
=> = = [/. ]. []. [] =3,5.80.60
=16800[ps]=16,8[ns]
tn sc tng l:
[] = +
= 26,4 + 16,8 = 31,29 []
Do > => Di thng b gii hn.
4. M PHNG
gii bi ton trn, nhm em la chn phng n lp trnh GUI trn Matlab.
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4.1 Code m phng
function pushbutton11_Callback(hObject, eventdata, handles)
%-------Tinh cong suat dau thu cho tuyen thong tin quang tren
Prx[dBm]------
Ptxstr = get(handles.Ptx,'String'); % Cong suat phatc
Lbnstr = get(handles.Lbn, 'String'); % Suy hao moi giac noi
skdstr = get(handles.skd,'String'); % So bo khuech dai
Lsoistr = get(handles.Lsoi,'String');% Suy hao trung binh cua
soi quang
Lstr = get(handles.L,'String'); % Cu ly thong tin
Lmhstr = get(handles.Lmh,'String'); % Suy hao moi moi han
smhstr = get(handles.smh,'String'); % So moi han
Pmargintbstr = get(handles.Pmargintb,'String'); % Suy hao du
phong cho thiet
bi
Pmargincapstr = get(handles.Pmargincap,'String'); % Suy hao du
phong cho ca;
Gkdstr = get(handles.Gkd,'String'); % He so khuech dai
Ptx0 = str2num(Ptxstr);
Lbn0 = str2num(Lbnstr);
skd0 = str2num(skdstr);
Lsoi0 = str2num(Lsoistr);
L0 = str2num(Lstr);
Lmh0 = str2num(Lmhstr);
smh0 = str2num(smhstr);
Pmargintb0 = str2num(Pmargintbstr);
Pmargincap0 = str2num(Pmargincapstr);
Gkd0 = str2num(Gkdstr);
Prx0 = Ptx0 - Lbn0*(2+skd0*2) - Lsoi0*L0 - Lmh0*smh0 -
Pmargintb0 -
Pmargincap0*L0 + Gkd0;
set(handles.Prx,'String',num2str(Prx0));
%--------Tinh Rtrans(Rbaund)[Gbps]--------------------
Rbitstr = get(handles.Rbit,'String');
codestr = get(handles.code,'String');
switch(codestr)
case '1B2B'
k=2;
case '1b2b';
k=2;
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case '5B6B';
k=6/5;
case '5b6b';
k=6/5;
otherwise;
end;
Rbit0 = str2num(Rbitstr);
Rtrans0 = Rbit0*k*0.001;
%--------Tinh do tan sac mode: Dmode[ns]---------------
Blimitstr = get(handles.Blimit,'String');
Lstr = get(handles.L,'String');
Blimitstr0 = str2num(Blimitstr);
Dmode0 = 0.44*L0/Blimitstr0;
%--------Tinh do tan sac mau: Dchr[ns]------------------
dentastr = get(handles.denta,'String');
dmatstr = get(handles.dmat,'String');
dentastr0 = str2num(dentastr);
dmatstr0 = str2num(dmatstr);
Dchr0 = dmatstr0*dentastr0*L0*10^(-3);
%--------Tinh do tan sac tong: Dt[ns]--------------------
Dt0 = sqrt(Dmode0^2 + Dchr0^2);
%--------Tinh do tan sac toi da cho phep: Dmax[ns]--------
Dmax0 = 1/(4*Rtrans0);
%--------Ket luan co bi gioi han dai thong hay khong ?---
if (Dt0 > Dmax0)
set(handles.ask,'String','Yes');
else
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set(handles.ask,'String','No');
end;
4.2 Giao din thit k
1. PHN CHIA CNG VIC2. BI3. LI GII4. M PHNG4.1 Code m phng4.2
Giao din thit k
