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7/8=0.875<br />
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0<br />
<br />
15<br />
14<br />
13<br />
12<br />
11<br />
10<br />
9<br />
8<br />
7<br />
6<br />
5<br />
4<br />
3<br />
2<br />
1<br />
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<br />
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1001<br />
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אא E٤<br />
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fs<br />
= ∆ × u V fs<br />
=<br />
2N<br />
KאVfs<br />
Wא١<br />
E١٥ J٢FKKKKKKKKKK Xu (max) = 1- ∆ × u = 1-<br />
1<br />
2N<br />
E٥<br />
<br />
W<br />
١{٠א J<br />
אאא J<br />
אאאאMSB=0א١٠٠٠F<br />
E٤<br />
J<br />
- ٤٤ -
אא <br />
אא <br />
אא<br />
٢٣٧<br />
א <br />
א <br />
א E٦<br />
٥ J٢אא E<br />
אאאאאא E<br />
א<br />
אאאאאא<br />
א <br />
אאא E<br />
אא<br />
FאאאEא J<br />
E1/16א1.47/162/16א1.67/16<br />
1.67/16FאאE J<br />
E1/16א<br />
٤אא٥ J٢א<br />
<br />
אJ٢ ٤אאאW٥ <br />
- ٤٥ -
אF<br />
אא <br />
אא <br />
אא<br />
٢٣٧<br />
א <br />
א <br />
E١٦ J٢FKKKKKKKKK<br />
א<br />
E٧<br />
EFא<br />
א–א <br />
∆× u 1 1 −(<br />
N + 1)<br />
∴Eu<br />
= = = = 2<br />
N<br />
N + 1<br />
2 2 × 2 2<br />
Where:Eu = the peak unipolar normalizederror.<br />
E١٧ J٢FKKKKKKKKKKKKKKKKKK lu<br />
אאאא J <br />
= Eu<br />
V<br />
fs<br />
=<br />
V fs<br />
=<br />
n+ 1<br />
2<br />
2<br />
−(<br />
n+<br />
1)<br />
. V<br />
fs<br />
W٦ J٢<br />
אא٦L<br />
א٢٠٠אא<br />
Kא<br />
∆ ×u אאE<br />
∆Vu אאEF<br />
Xu(max)EF<br />
Vu(max)EF<br />
<br />
<br />
EuEF<br />
lu EF<br />
<br />
אאא <br />
אאא<br />
אא-1 ≤ X < 1 +1 −1<br />
K١ J٢אא١٦٢٤،٤<br />
<br />
٢ J٩ J١ J٢<br />
E١<br />
E٢<br />
E٣<br />
- ٤٦ -
אא <br />
אא <br />
אא<br />
٢٣٧<br />
א <br />
א <br />
<br />
Xb<br />
א<br />
.<br />
K<br />
K<br />
K<br />
אא אאא<br />
FXbE<br />
<br />
− 8<br />
= −1<br />
0000<br />
8<br />
K<br />
K<br />
K<br />
K<br />
K<br />
K<br />
0 1000<br />
K<br />
K<br />
K<br />
K<br />
K<br />
K<br />
K<br />
K<br />
K<br />
7 0.875<br />
1111<br />
= 8<br />
אJ٢ ٤אאאאאאW١ <br />
E1 LSBאF ( ∆X ) b<br />
אא<br />
<br />
E٤<br />
E١٧ J٢F<br />
∆X<br />
b<br />
=<br />
2<br />
1 −n+<br />
1<br />
= 2<br />
n− 1<br />
E١٨ J٢F<br />
∆V<br />
b<br />
= ∆X<br />
b<br />
V<br />
fs<br />
- ٤٧ -<br />
V<br />
=<br />
2<br />
∆V b אא<br />
fs −N<br />
+ 1<br />
= 2<br />
N − 1<br />
אאאאאאאאא<br />
E١٩ J٢F<br />
אאא <br />
X b<br />
(max) = 1− ∆X b<br />
V<br />
= 1−<br />
2<br />
fs<br />
<br />
− N + 1<br />
E٥<br />
E٦
אא <br />
אא <br />
אא<br />
٢٣٧<br />
א <br />
א <br />
E٢٠ J٢F<br />
E١ J٢אFW<br />
٨<br />
M<br />
2<br />
1<br />
= 2<br />
N −<br />
M<br />
N −<br />
E٢١ J٢F −1<br />
= 2<br />
1 −1<br />
2<br />
٨<br />
•<br />
•<br />
אא١٠٠٠אא٠אMSB<br />
אMSBאאEF٢אאא<br />
E٢٢ J٢F complement<br />
⎡ 1 010 → 2<br />
8<br />
aries ⎢<br />
⎢ 0 010 → 6<br />
⎣<br />
−<br />
MSB 8<br />
⎫<br />
⎬<br />
8<br />
⎭<br />
8<br />
<br />
0001 → − 7 ⎫<br />
8⎪<br />
⎬<br />
8<br />
1 8<br />
1001 →<br />
8<br />
⎪<br />
⎭<br />
אאא٦ J٢א<br />
∆Ε b<br />
٢٣ J٢<br />
٢٤ J٢ l<br />
b<br />
א<br />
אאאאא<br />
∆X<br />
2<br />
b −N<br />
∆Εb<br />
= = 2<br />
אאאאא<br />
= E V = 2<br />
b<br />
fs<br />
−N<br />
V<br />
fs<br />
<br />
•<br />
•<br />
<br />
E٧<br />
E٨<br />
<br />
- ٤٨ -
אא <br />
אא <br />
אא<br />
٢٣٧<br />
א <br />
א <br />
<br />
א٢–٢<br />
אאאאWא<br />
K<br />
<br />
אאאאאאא١ J٢ J٢<br />
Wאdcאא<br />
١ E+V-VFאא<br />
٠0V<br />
-V١ +Vא<br />
E٠F<br />
אאdcאאאאאW<br />
<br />
אאאא،א<br />
•<br />
•<br />
E١<br />
אאWduty cycleא<br />
E٢<br />
- ٤٩ -
אא <br />
אא <br />
אא<br />
٢٣٧<br />
א <br />
א <br />
אאאNRZא<br />
אאאRZ<br />
•<br />
•<br />
אWא<br />
אא<br />
אאאאא<br />
אאאאWאאאא<br />
،אאאאKאא<br />
אאא<br />
EBPRZFאאאאKאא<br />
K<br />
אא<br />
אאאאא<br />
א<br />
א،BPRBPNRZUPRZUPNRZא<br />
א،BPRZ-AMI<br />
BPRZ-AMIאאKEF<br />
אK<br />
E٣<br />
•<br />
•<br />
E٤<br />
<br />
E٥<br />
•<br />
•<br />
<br />
- ٥٠ -
אא <br />
אא <br />
אא<br />
٢٣٧<br />
א <br />
א <br />
- ٥١ -<br />
אא<br />
،+V/2،אאא<br />
0Vאאא<br />
אאאEFא<br />
אא<br />
Kאאאא<br />
E٦<br />
<br />
•<br />
•<br />
•<br />
אא٢ J٢ J٢<br />
(Non Return to Zero Level: NRZ-L)אא<br />
אאEHIGHFאW١<br />
אאELOWFאW٠<br />
<br />
W<br />
J<br />
אאאא J<br />
א<br />
א J<br />
אאאא<br />
אK<br />
•<br />
•<br />
אF(Non Return to Zero Mark: NRZ-M)אא<br />
א Edifferential Coding<br />
אאאW١<br />
،אא J<br />
<br />
،אא J<br />
<br />
אאאאאW٠<br />
K<br />
•<br />
•<br />
E١<br />
E٢
אא <br />
אא <br />
אא<br />
٢٣٧<br />
א <br />
א <br />
W<br />
J<br />
אאאא J<br />
(Non Return to Zero Space: NRZ-S)אאא<br />
אאאאאW١<br />
<br />
אאאW0<br />
،אא J<br />
<br />
،אא J<br />
<br />
W<br />
J<br />
Kאאאא J<br />
•<br />
•<br />
אאאאUPRZ)W (Unipolar Return to Zero:<br />
אאאW١<br />
אאאא J<br />
<br />
J<br />
<br />
אא J<br />
<br />
אאא<br />
אאאW٠<br />
W<br />
אא J<br />
KNRZ J<br />
•<br />
•<br />
E٣<br />
E٤<br />
- ٥٢ -
אא <br />
אא <br />
אא<br />
٢٣٧<br />
א <br />
א <br />
אאאאW E٥<br />
(Bipolar Return to Zero: BPRZ)<br />
(Polar Return to Zero: BPRZ)<br />
<br />
אאאW١<br />
אאאא0V J<br />
J<br />
אאא0V<br />
אאאW٠<br />
אאאא0V J<br />
J<br />
אאא0V<br />
،אאאאאאא<br />
E-V0V +VFא<br />
אא<br />
<br />
•<br />
•<br />
•<br />
•<br />
אאW<br />
KאאאW<br />
E٦<br />
(Return to Zero-Alternate Mark Inversion: RZ-AMI)<br />
אאאW١ •<br />
אאאאW<br />
אאאא0V J<br />
J<br />
אאא0V<br />
אא J<br />
אאELOWFאW٠<br />
W<br />
אאאא٠אאאא٠<br />
Kאאאא<br />
•<br />
- ٥٣ -
אא <br />
אא <br />
אא<br />
٢٣٧<br />
א <br />
א <br />
W<br />
Kאאאא J<br />
J<br />
KNRZ J<br />
W<br />
Wאאא E٧<br />
Biphase- Level (BI Φ –L) or Manchester II code<br />
<br />
אאאW١<br />
אאא J<br />
J<br />
אאא<br />
אאW٠<br />
אא<br />
J<br />
KNRZ J<br />
•<br />
•<br />
•<br />
W<br />
W<br />
Kאאא J<br />
<br />
Wאאא E٨<br />
Biphase- Mark (BI Φ –M) or Manchester I code<br />
<br />
אאאW١<br />
אאא J<br />
J<br />
אאא<br />
אאW٠<br />
•<br />
•<br />
- ٥٤ -
אא <br />
אא <br />
אא<br />
٢٣٧<br />
א <br />
א <br />
- ٥٥ -<br />
J<br />
KNRZ J<br />
W<br />
W<br />
Kאאא J<br />
Wאאאא E٩<br />
Biphase- Space (BI Φ –S) code<br />
אאW١ •<br />
אאאW٠<br />
אאאא J<br />
J<br />
אא<br />
אאא<br />
א J<br />
KNRZ J<br />
•<br />
•<br />
W<br />
W<br />
Kאאא J<br />
Wא E١٠<br />
Delay modulation (DM) or miller code<br />
אW١ •<br />
א،٠אW٠<br />
אאאא<br />
•<br />
W<br />
אא J<br />
W<br />
Kאאא J<br />
KNRZ J
אא <br />
אא <br />
אא<br />
٢٣٧<br />
א <br />
א <br />
א<br />
א<br />
אא DC א<br />
+ V / 2 f b / 2 UPNRZ<br />
O f P / 2 BPNRZ<br />
+ V / 4 f b UPPZ<br />
א O V f b BPRZ<br />
O V f b / 2 BPRZ-AMI<br />
<br />
<br />
אJ٢ אאאW٧ <br />
<br />
- ٥٦ -
אא <br />
אא <br />
אא<br />
٢٣٧<br />
א <br />
א <br />
<br />
١١NRZ – L E١<br />
٠٠<br />
<br />
אא١NRZ –M E٢<br />
אא٠<br />
<br />
אא١NRZ –S E٣<br />
אא٠<br />
<br />
١٠١URZ – E٤<br />
٠٠<br />
<br />
١٠١BPRZPRZ E٥<br />
J١٠٠<br />
١BRZ – AMI E٦<br />
א١٠ <br />
אאJ١٠ <br />
٠٠<br />
<br />
١٠١BIΦ-L E٧<br />
٠١٠<br />
<br />
٠١١٠١BIΦ – M E٨<br />
אא٠<br />
<br />
אא١BIΦ – S E٩<br />
٠١١٠٠<br />
- ٥٧ -
אא <br />
אא <br />
אא<br />
٢٣٧<br />
א <br />
א <br />
אא١DM E١٠<br />
אאא٠<br />
Kאאא<br />
אJ٢ א٨<br />
- ٥٨ -
אא <br />
אא <br />
אא<br />
٢٣٧<br />
א <br />
א <br />
אאא٣–٢<br />
PCM/TDM<br />
אאאW EאFא<br />
EFKא<br />
K<br />
<br />
אאא١ J٣ J٢<br />
אאאE١<br />
KEPAM/TDMFאא<br />
KWאE٢<br />
KfNא<br />
Fs = fn = 2 fm<br />
אאא<br />
אאאאFאאא<br />
Eא<br />
•<br />
•<br />
•<br />
•<br />
E<br />
א٩ J٢אE٣<br />
٢١ J٢F<br />
Tf = TN = 1<br />
2fm<br />
Eframe timeFא<br />
•<br />
אJ٢ אאאW٩ <br />
- ٥٩ -
אא <br />
אא <br />
אא<br />
٢٣٧<br />
א <br />
א <br />
Eword timeFא<br />
•<br />
E٢١ J٢F <br />
= 1<br />
K<br />
Tω= Tf<br />
2K fm<br />
Ebit durationFא •<br />
Tω 1<br />
E٢٢ J٢F <br />
τ = =<br />
N 2K N fm<br />
Wאא<br />
E٤<br />
<br />
<br />
- ٦٠ -<br />
<br />
لاحظ: عرض نطاق<br />
אאאא<br />
Kאא<br />
<br />
אא٢ J٣ J٢<br />
אאאא،א<br />
٣٢אאEUS – 24 Channel SystemF٢٤<br />
K<br />
<br />
EUS – 24 Channel SystemFWEאF٢٤١ J٢ J٣ J٢<br />
אאKECode WordsF٢٤אE١<br />
אאאאאאא <br />
K241אא<br />
E٢٤١FאאאאE٠Fא<br />
Kאא<br />
•<br />
•
אא <br />
אא <br />
אא<br />
٢٣٧<br />
א <br />
א <br />
٠<br />
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E<br />
1<br />
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٤<br />
٥<br />
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א<br />
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١٢<br />
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KKKKKKKKK<br />
٨EFאאא٢٤<br />
١٩٣Zא١H١٩٢Z٨х٢٤Wא<br />
Kא٠א24אאאא<br />
1<br />
١٢٥µs א<br />
8000<br />
K٠אאאאאאאא<br />
KEFrame Alignment Word: FAWFאאא<br />
אא،٢٤אא<br />
٢٠<br />
٢١<br />
٢٢<br />
TI FAWאאא١٢<br />
١٠٠٠١١٠١١١٠٠<br />
ESuperframeFאEF١٢<br />
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٢٣<br />
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•<br />
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W٢٤א<br />
٢٤אETI MultiplexerFא<br />
E١٢٥µsFאE٨FאPCM<br />
אאאאאא<br />
אKאאא<br />
٨אא٨אא٨אW،<br />
K٢٤אאא،אא<br />
אאאאאאאאאא<br />
אאאאאKKKK<br />
TI FAWאאאא١٢א<br />
K<br />
K١<br />
K٢<br />
K٣<br />
K٤<br />
K٥<br />
- ٦١ -
אא <br />
אא <br />
אא<br />
٢٣٧<br />
א <br />
א <br />
W٢٤א<br />
אאKא٢٤א<br />
אאאEFאאK١٩٢<br />
،א٨٠٠٠אאK١٩٣<br />
<br />
Kא١٥٤٤٠٠٠א١٩٣x٨٠٠٠<br />
<br />
אJ٢ ٢٤W١٠<br />
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W٣٢אא<br />
EBandwidth = Bit rate אZאF<br />
125µsאfs=8kHz א<br />
125µ<br />
s<br />
= ≈<br />
193<br />
١٩٣Z٨C٢٤H١אאאא<br />
0.647668 µ s<br />
Tb<br />
אאא<br />
•<br />
•<br />
•<br />
א<br />
Rb<br />
=<br />
1 193<br />
= =<br />
Tb 125µ<br />
s<br />
1.544 Mbit / s<br />
•<br />
- ٦٢ -
אא <br />
אא <br />
אא<br />
٢٣٧<br />
א <br />
א <br />
אאאא١{٥٤٤<br />
B<br />
1 1<br />
= = = 1. 544 MHz<br />
T<br />
0.64766<br />
T<br />
B<br />
•<br />
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אJ٢ ٢٤אאאאאW١١ <br />
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E32 Channel SystemFWEאאF٣٢٢ J٢ J٣ J٢<br />
אאECode WordsF ٣٢אE١<br />
אאK <br />
K31٠אא<br />
אאאE١٦FאE٠Fאא<br />
אאE٣١١٧١٥١Fאא<br />
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١٩٣Zא١H١٩٢Z٨х٢٤Wא<br />
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Kא١٦٠א٣٠אאאא<br />
1<br />
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Synchronization Fאאאאאאאא<br />
K١٦٠אאאEand signaling<br />
•<br />
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- ٦٣ -
אא <br />
אא <br />
אא<br />
٢٣٧<br />
א <br />
א <br />
W٣٢א<br />
٨FאPCM٣٠אא<br />
E١٢٥µsFאE<br />
אאאאאא<br />
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٨אא٨אא٨אאאW<br />
אא،אאא١٥אאKא<br />
אאאאKאאא<br />
א،١٨א٨١٧א٨١٦א٨אא<br />
K٣٢א٣١אא<br />
אאאאאאאאאאאא<br />
KKKKאא<br />
W٢٤אא<br />
<br />
EBandwidth = Bit rate אZאF<br />
125µsאfs=8kHz א<br />
125µ<br />
s<br />
= ≈<br />
256<br />
0.488 µ s<br />
Tb<br />
٢٥٦Z٨C٣٢אאאא<br />
אאא<br />
K١<br />
K٢<br />
K٣<br />
K٤<br />
•<br />
•<br />
•<br />
Rb =<br />
1 256<br />
= =<br />
Tb 125µ<br />
s<br />
2<br />
א<br />
Mbit / s<br />
אאאא١{٥٤٤<br />
B<br />
1<br />
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T<br />
T<br />
B<br />
1<br />
0.488<br />
MHz<br />
•<br />
•<br />
<br />
- ٦٤ -
אא <br />
אא <br />
אא<br />
٢٣٧<br />
א <br />
א <br />
W٣٢א<br />
<br />
<br />
אJ٢ אאא٣٢אW١٢ <br />
<br />
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٣٢אאאאאא<br />
<br />
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אJ٢ ٣٢אאאאאW١٣ <br />
Kאאאא٣٢L٣٠א١٣ J٢א<br />
<br />
<br />
<br />
<br />
- ٦٥ -
אא <br />
אא <br />
אא<br />
٢٣٧<br />
א <br />
א <br />
٤–٢<br />
EDelta Modulation: DMF<br />
א،אאאW<br />
Kאאאאא<br />
Kאאא٠אאא١<br />
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•<br />
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ELinear Delta Modulation: DMFא١ J٤ J٢<br />
אאאא א<br />
<br />
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אJ٢ אW١٤ <br />
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אא x(t) אאאאEdifferential circuitFאאאE١<br />
K e(t) אz(t)<br />
e(t) = x(t) – z(t)<br />
אאאQ(t)אEsignal quantizerFאE٢<br />
K e(t)אא<br />
e(t)<br />
- ٦٦ -
אא <br />
אא <br />
אא<br />
٢٣٧<br />
א <br />
א <br />
<br />
e(t)<br />
אE+1Fe(t)אאאE٣<br />
K e(t) אE+1F<br />
<br />
KEstep sizeF∆<br />
אאאE٤<br />
١٥ J٢אאאאא<br />
<br />
אJ٢ אאאW١٥<br />
W<br />
K،אאא،אא<br />
W<br />
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Estep sizeF∆א J<br />
fsא J<br />
•<br />
- ٦٧ -
אא <br />
אא <br />
אא<br />
٢٣٧<br />
א <br />
א <br />
Wא<br />
Eslope overloadFא J<br />
KאאEgranular אאnoiseF J<br />
Esignal to noise ratio S/NFא\אא<br />
אK∆ <br />
•<br />
אJ٢ overloadFאW١٦ Eslope<br />
אJ٢ noiseFאאW١٧ Egranular<br />
<br />
אJ٢ ∆אES/NFאLאW١٨ <br />
<br />
- ٦٨ -
אא <br />
אא <br />
אא<br />
٢٣٧<br />
א <br />
א <br />
Eadaptive delta modulationFא٢ J٤ J٢<br />
،אא،א<br />
אאא،<br />
אאאא<br />
אאאא<br />
אאא،אאאfunctionF Estair case<br />
Wאא،א<br />
،אאא J<br />
אאKאא<br />
אאאא J<br />
KאאKאאא<br />
E١<br />
E٢<br />
E٣<br />
E٤<br />
<br />
٣ J٢ J٤ J٢<br />
אאW<br />
אאאEintegratorF<br />
אא،אא<br />
KEvariable gain amplifierFאאא<br />
אאאאאא<br />
K<br />
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אאW<br />
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ESong algorithmFא J<br />
אא∆אאאאאא<br />
אאאKאא∆אא<br />
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E١<br />
E٢<br />
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- ٦٩ -
אא <br />
אא <br />
אא<br />
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א <br />
א <br />
<br />
אJ٢ algorithmFאW١٩ ESong<br />
אאEdamped oscillationF<br />
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ESpace shuttle algorithmFאאא J<br />
Kאאאאאאא<br />
אאאא،אKא،<br />
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אJ٢ algorithmFאאW٢٠ ESpace shuttle<br />
- ٧٠ -
٣ אא<br />
אאא <br />
المؤسسة العامة للتعليم الفني والتدريب المهني<br />
אאאא<br />
א אא<br />
אא
אא <br />
אא<br />
אא<br />
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א <br />
א <br />
אאWאא<br />
Band Pass Modulation (BPM)<br />
אאWאאאאאFא<br />
אEאאFאאKE<br />
א،א، אWא<br />
W אא<br />
(ASK)(Amplitude shift keying)אא J<br />
(FSK)(Frequency shift keying)אא J<br />
<br />
(PSK)(Phase Shift keying)אא J<br />
<br />
אאWאאאK٪٩٠ <br />
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אא١٥W <br />
<br />
אאWאא <br />
<br />
אאאאאאאאWאא<br />
אאK <br />
<br />
- ٧١ -
אא <br />
אא<br />
אא<br />
٢٣٧<br />
א <br />
א <br />
(Baud rate)א(bit rate)אא1-3<br />
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(ASK,FSK,PSK)אאאאא<br />
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W(Binary modulation)אא J١<br />
אאאאא(bit) <br />
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W<br />
W<br />
אאאאFאאWRb<br />
אאאאsec/ Ebit<br />
אאאאאFאאאWRs<br />
<br />
KEאאאאWאא<br />
KאאאWM<br />
EאאאאאFאאWN<br />
W(Quadrature modulation)אא J٢<br />
WEאאאFאאא<br />
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(2-3)<br />
- ٧٢ -
אא <br />
אא<br />
אא<br />
٢٣٧<br />
א <br />
א <br />
- ٧٣ -<br />
WEאFאאא J٣<br />
WEאFאאאא(N)<br />
<br />
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2<br />
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M =<br />
N = log 2 M (3-3)<br />
<br />
W(ASK)אא<br />
2-3<br />
אא(Ac cos wst)א(Ac sin wct)אאא<br />
אאE٠FאאאאאE١FאאאW <br />
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t <br />
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<br />
אאאאE1-3F<br />
א(NRZ-L)א Vm(t)אאE١<br />
אא<br />
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W(ASK)אאאאאE٢<br />
V ASK(t)<br />
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(ASK)אא<br />
V ASK(t) = A [1±m] cos 2πfct (4-3 ) .<br />
א(m)W
אא <br />
אא<br />
אא<br />
٢٣٧<br />
א <br />
א <br />
(2-3)אא<br />
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(Efficiency)<br />
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<br />
- ٧٤ -
אא <br />
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٢٣٧<br />
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(5-3)א<br />
( 4-3)אאא<br />
<br />
- ٧٥ -
אא <br />
אא<br />
אא<br />
٢٣٧<br />
א <br />
א <br />
<br />
(OOK ) (4-3)<br />
(OOKF(OOK)<br />
אאאאאאא<br />
EאאF(Balanced Modulators)<br />
אEOOKF(5-3)אאא <br />
<br />
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EOOKאFE5-3F<br />
<br />
- ٧٦ -
אא <br />
אא<br />
אא<br />
٢٣٧<br />
א <br />
א <br />
(OOK Detection)אא<br />
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(coherent detection)אאאE١<br />
(synchronous detection)אא<br />
א(reference carrier)אאא<br />
אאאאKאאאא<br />
אאאאאאא<br />
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אE6-3Fאאאאאאא <br />
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(Non Coherent Detection)אאאE٢<br />
(Asynchronous detection)אא<br />
אאאאאאאאא<br />
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EאאאאאאFE7-3F<br />
- ٧٧ -
אא <br />
אא<br />
אא<br />
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אאאאchargeF Etime constant of<br />
Eforward resistanceFאא<br />
אאאEreverse biasedFא<br />
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אאTZR*C<br />
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אאאאאאאאאE٢<br />
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binary FאאאאאאאE٣<br />
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EFcFEFmFאאא<br />
<br />
- ٧٨ -
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אא<br />
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٢٣٧<br />
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<br />
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ERbFEdata rateFאEFmFאאE8c-3Fא<br />
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אEASKFאא<br />
- ٧٩ -
אא <br />
אא<br />
אא<br />
٢٣٧<br />
א <br />
א <br />
אאFWאאאאE <br />
Performance: ( bit error rate & symbol error rate )<br />
אאאאאאאE١<br />
(PB) (Probability of bit error)אאא(BER)<br />
(Probability of symbol error)אאא<br />
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אאFאאאE٢<br />
אאאאאEאאא<br />
- ٨٠ -<br />
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(BASK,BFSK,BPSK)אא J<br />
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(µASK,µFSK,µPSK)אא J<br />
אאא(N)א(N)<br />
אאW <br />
PB = PE / N = PE / log2M<br />
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אאאאאFא(BER)אאE٤<br />
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אא <br />
אא<br />
אא<br />
٢٣٧<br />
א <br />
א <br />
א(BASK)א<br />
(Performance of binary BASK)<br />
אאאאאאא<br />
אאאאאא<br />
אאK <br />
אאאאאאא<br />
(Coherent detection)<br />
א<br />
: אאאE١<br />
PB=PE= 1/2 erfc<br />
= 1/2 erfc(<br />
Eb / 2No<br />
2<br />
A Tb / 8No)<br />
=1/2 erfc (<br />
C / 4N )<br />
(7-3)<br />
(٢ الكشف اللا ترابطي detection): (Non Coherent<br />
PB = PE =<br />
( Eb/<br />
2No)<br />
e −<br />
=<br />
1/2<br />
( C / 4N)<br />
e −<br />
= 1/2<br />
( A2Tb/8No)<br />
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(8-3)<br />
EF(bit)אEb = (E1+Eo) / ٢ <br />
אא(9-3)א <br />
<br />
<br />
E1=C*Tb = A2 Tb/2<br />
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(OOKF(BASK)(9-3)<br />
<br />
- ٨١ -<br />
אאאאK
אא <br />
אא<br />
אא<br />
٢٣٧<br />
א <br />
א <br />
אאאK<br />
Eb = E1+E2/2= C Tb /2 = A2*Tb/4<br />
:<br />
C1=C= A2/2<br />
Co = 0<br />
אאאאאאא<br />
אאא <br />
אאאv))EAF) (A – Peak amplitude of the received carrier<br />
No = N/BT= N/Rb = KT (W/HZ)<br />
N= KT*BT (W)<br />
K =(1.38* 10 −23<br />
T= ( TA+TR)<br />
JK)<br />
אאא <br />
אא<br />
<br />
(K)אאא<br />
<br />
TA: EאאFאאW(TA)<br />
TR=T1+T2/a1 =T3/a1+a2+…………….<br />
EאאאFא<br />
T1,T2,T3,……..<br />
G1,G2,G2,….<br />
C/N<br />
אאא<br />
אאא<br />
אאא<br />
<br />
WEBERFאאEBASK)א<br />
<br />
- ٨٢ -
אא <br />
אא<br />
אא<br />
٢٣٧<br />
א <br />
א <br />
(10MHZ)<br />
(5*10(-5) W/HZ)<br />
<br />
EBERFE10-3F<br />
<br />
W2-3<br />
א (OOK)אE10 Kbit/sF<br />
אאאא<br />
(BER)<br />
א (-2)V) (10<br />
אאא<br />
אא3-3<br />
Frequency Shift Keying (FSK)<br />
אאEאאFEFsFאאאאאאא<br />
Ebase bandFאאאאאEאFEFmF<br />
- ٨٣ -<br />
KEpolarFא<br />
W<br />
אאאאאאאאא∆F <br />
EFCFא<br />
<br />
WFSK<br />
WאEFSKFאאE١<br />
V FSK (t) = (Ac cos { 2 π (fc + V M (t)) ∆f ) t }<br />
א(FSKF<br />
(Volts)אא<br />
(9-3)<br />
-V FSK<br />
:<br />
- A<br />
حيث<br />
(HZ)EאאFאא JFc<br />
(HZ)(Vm (t))אאאאא J∆f
אא <br />
אא<br />
אא<br />
٢٣٧<br />
א <br />
א <br />
( ± ١)אאאאא JVm (t)<br />
Logic (1) = +1 , Logic (0) = -1<br />
Wא(9-3)אE٢<br />
(a) V FSK (t) = A cos [ 2 π (fc + ∆f) t ] = A cos 2 π fmt .<br />
for a logic 1 , Vm (t) = +1 (3-10)<br />
(b) V FSK (t) = A cos [ 2 π (fc - ∆f) t ]= A cos 2 π fst<br />
for a logic 0 , Vm (t) = -1<br />
W<br />
אא(Logic 1)(Logic 0)אאE<br />
WEאFא<br />
Fm=Fc+∆FELogic 1Fא<br />
Fs = Fc-∆F ELogic 0Fאא<br />
אאאאא(Fc)א(Fm &Fs) אאאאE<br />
أو<br />
(Fc ± ∆F)<br />
: (FSK) <br />
(VCO) EאאאEFSK) <br />
אא<br />
<br />
(١<br />
( Voltage Controlled Oscillator)<br />
<br />
(VCO) (12-3) <br />
مبدأ عمل جهاز ال(VCO):<br />
KאאEVoltageFא<br />
(FSK)א،אא<br />
אEVCOFא،(Vm(t) = ± 1)אE٣<br />
(٢<br />
EF,FsF<br />
- ٨٤ -
אא <br />
אא<br />
אא<br />
٢٣٧<br />
א <br />
א <br />
:(FSK) <br />
EFSK)E13-3F<br />
W<br />
(sec)אא JTm<br />
(HZ)(Vm (t))אאאא JFm<br />
(Rb= 2Fm) (bit/sec)אEbitsFא JRb<br />
- ٨٥ -<br />
(Mark Frequency)א JFm<br />
ESpace Frequency Fאא JFs<br />
WEFSKFEBaud rateFאאERbFEbitsFא<br />
אאאאאEFSKFE١<br />
<br />
Kאא<br />
KאאאאE٢<br />
WאאE٣<br />
אאאW(Rb)Ebit rate)א<br />
אאאrate) אאאW(Baud rate or symbol <br />
(Fs)אא(Fm)אאא(9-3)אאE٤<br />
Kאאאאאאא<br />
Bit rate =Symbol rate (Baud rate)<br />
Rb (bit/sec) = Rs ( Symbol/sec) = Baud rate ( baud)
אא <br />
אא<br />
אא<br />
٢٣٧<br />
א <br />
א <br />
<br />
(FSK Bandwidth)W(FSK)אא<br />
אEFSKF(BT)אאאE١<br />
אFM))אא(3-11) <br />
Fm = Rb/2<br />
B T = 2 (∆f + fm) (11-3)<br />
(∆F =Fm-Fs/2) W <br />
(Fc) אאאאאאא : <br />
אEFאאאאאאW<br />
אאא<br />
( ١٢-٣)א (11-3) א (Fm ∆F) E٢<br />
B T = 2 ∆ f + 2 fm = fm – f S + R b (12-3)<br />
(FSK)<br />
אאא (BT)<br />
EFSKFאאE14-3F<br />
<br />
אאאwaves) x/x)אא(Pulsed sinusoidal (sin<br />
(12-3)אא(FSK)<br />
W(Rb)אא(Fm)אא<br />
Rb = 2Fm<br />
- ٨٦ -
אא <br />
אא<br />
אא<br />
٢٣٧<br />
א <br />
א <br />
אאאאאא<br />
אאאא(14-3)<br />
Kאאא<br />
<br />
:3-3<br />
E200 K bit / secFאאENRZ-LFאEPCMF<br />
K(150KHZ)אאאאאא،(FSKF<br />
א<br />
<br />
Wא<br />
אאאאאא J١<br />
K(Fs)א( Fm)<br />
אאאא(Logic 1)אאא J٢<br />
אאאא<br />
אא0) (Logic<br />
א(Pulsed RF Signal)אאאאא J٣<br />
(base band)אא<br />
Kאאאאא J٤<br />
אאא J٥<br />
Kא(Binary restoration)אאאא<br />
<br />
- ٨٧ -
אא <br />
אא<br />
אא<br />
٢٣٧<br />
א <br />
א <br />
W(FSK)אאאE<br />
FSK Coherent detection<br />
<br />
<br />
EFSKFאאאE15-3F<br />
Wא<br />
אאאאאאא K١<br />
אאאאאא<br />
א<br />
Kאאאאאאא<br />
WאאאELogic 1Fאאאא J<br />
Vr(t) = Acos wm(t) (13-3)<br />
Wאאאא J<br />
Vc(t) = 2A cos(2) wmt = A( 1+ cos 2wmt)<br />
(14-3)<br />
אאאאE14-3)אאאאא<br />
(differential amp.)אאא<br />
אאאאא<br />
Vo (t) = Gv Vd(t) = A*Gv = positive constant<br />
א15-3)) :<br />
(15-3)<br />
ELogic 1Fאאאאא<br />
אELogic 0Fאאאאא K٣<br />
Kאא<br />
K٢<br />
- ٨٨ -
אא <br />
אא<br />
אא<br />
٢٣٧<br />
א <br />
א <br />
אאW(Performance) <br />
אEאאאW <br />
BER = PB = ½ erfc<br />
⎛<br />
⎜<br />
⎝<br />
Eb<br />
2No<br />
⎟ ⎞<br />
⎠<br />
PcTb ⎞<br />
= ½ erfc ⎜<br />
⎟ ⎝ 2No<br />
⎠<br />
= ½ erfc<br />
E b = P C T b<br />
⎛<br />
⎛<br />
⎜<br />
⎜<br />
⎝<br />
2<br />
A Tb ⎞<br />
⎟<br />
4No<br />
⎟<br />
⎠<br />
(3-16)<br />
P C =<br />
No =<br />
- ٨٩ -<br />
W<br />
א(EbF<br />
אאEPcF<br />
אאאENoF<br />
אאאE<br />
<br />
BER = PB = ½ exp ( -E b ) (3-17)<br />
2N O<br />
2<br />
⎛ A Tb ⎞<br />
= ½ erfc ⎜<br />
⎟ ⎝ 2No<br />
⎠<br />
<br />
אאאאאא<br />
אאא(bits)אאא<br />
A2<br />
2<br />
P N<br />
B T<br />
אאא(PB)אאE16-3F<br />
א
אא <br />
אא<br />
אא<br />
٢٣٧<br />
א <br />
א <br />
PB =<br />
F<br />
(<br />
-E b<br />
2N O<br />
) =F(C/N)<br />
(FSK)אא<br />
(16-3) <br />
: 4-3<br />
(FSK)אאאאאאאWא( BER)<br />
(1KHZ,2KHZ):אאא(0.4 V)א(2sec)(bit)א<br />
אאאw/HZ) (10(-12)<br />
אאא(13-3)א(BER) <br />
אא4-3<br />
Phase Shift Keying (PSK)<br />
<br />
אאאFאאאאא<br />
אEאאאW <br />
K( ASK)א J<br />
K(FSK)אא J<br />
<br />
- ٩٠ -
אא <br />
אא<br />
אא<br />
٢٣٧<br />
א <br />
א <br />
Wאאאא<br />
(Binary PSK)אאאאאאPSKE١<br />
Eאא<br />
(Quadrature אאאאאאאPSK) PSKE٢<br />
KEאא<br />
(µ-PSK) א) PSK)אPSKE٣<br />
אEאאFאאEMFאאF<br />
Kאאא<br />
W<br />
(18-3)<br />
W<br />
EFא JNb<br />
EאאאFאא JM<br />
W5-3<br />
KאאאאKM= 2 EPSKF<br />
(Binary PSK) אאא<br />
<br />
(BPSK)<br />
אאא(17-3)<br />
- ٩١ -
אא <br />
אא<br />
אא<br />
٢٣٧<br />
א <br />
א <br />
א(PCM)U (t)אאא J١<br />
KE-90°א٩٠°F<br />
EאאFאא(i)א(Ui )אא J٢<br />
אW <br />
(19-3 )<br />
Ui ={+1 for logic (1)<br />
{-1 for logic (0)<br />
W<br />
(volts)א JV<br />
אא JUi<br />
W (19-3)א<br />
-Eπ / 2Fאlogic (1) J<br />
HEπ / 2Fאlogic (0) J<br />
Wא(19-3)אאאא J٣<br />
<br />
<br />
<br />
E20-3F<br />
<br />
- ٩٢ -
אא <br />
אא<br />
אא<br />
٢٣٧<br />
א <br />
א <br />
WEBPSKFא<br />
א(BPSK)א E١<br />
אאE٠١F <br />
<br />
<br />
(BPSK)<br />
א(18-3)<br />
٢) الحامل هو :<br />
Vc (t)=Vsin wct<br />
<br />
<br />
(BPSK) א<br />
(19-3) <br />
- ٩٣ -
אא <br />
אא<br />
אא<br />
٢٣٧<br />
א <br />
א <br />
VBPSK(t) <br />
:V BPSK(t)<br />
(٣<br />
א<br />
<br />
<br />
BW=2fm=Rb <br />
t <br />
f<br />
fc-fm<br />
fc+fm <br />
<br />
<br />
EVBPSKFאאE20-3F<br />
EFאאאאאאE٤<br />
<br />
V BPSK(t) = sin 2πFmt*sin2πfct<br />
= 1/2[ cos 2 π (fc-fm)- 1/2 cos2π (fc+fm)t<br />
B= (fc+fm) – (fc+fm)=2fm=Rb<br />
BT = RbWא<br />
B= 2(∆f+fm)=2fm+2∆f<br />
2∆f=0<br />
]<br />
<br />
W<br />
<br />
<br />
Wאא<br />
EאאאאF<br />
Wאאא<br />
W<br />
Wאא <br />
B= 2fm = Rb<br />
- ٩٤ -
אא <br />
אא<br />
אא<br />
٢٣٧<br />
א <br />
א <br />
אא(BPSK) <br />
<br />
WEBPSK)E<br />
<br />
(OOK)אאE21-3Fאא<br />
אא(OOK)אK <br />
<br />
<br />
ui=<br />
Binary<br />
data<br />
VSinωct<br />
Balanced<br />
Modultor<br />
Ui V sin wct<br />
Bw=Rs<br />
BPF<br />
Ui V sinωct<br />
V BPSK(t)<br />
Reference<br />
Carrier<br />
oscillator<br />
(BPSK)(21-3)<br />
<br />
W(BPSK)E<br />
אאא(Ui)אאא<br />
אאאאאאא<br />
אאmodulator) אא (balanced<br />
Kאאאא<br />
<br />
- ٩٥ -
אא <br />
אא<br />
אא<br />
٢٣٧<br />
א <br />
א <br />
Vd(t)=2uiVsinwct<br />
Vo=VUi={+v Logic 1<br />
<br />
<br />
input signal<br />
Balanced<br />
L<br />
Vo=V<br />
P F<br />
{-v logic 0<br />
detector<br />
V BPSK(t) =<br />
VUisinωct<br />
2 sinωct<br />
<br />
<br />
Carrier<br />
oscillator<br />
<br />
(BPSK)E22-3F<br />
אאאW J<br />
אאאW J<br />
אאאאאאא(LPF)אאW <br />
<br />
- אאאאאא<br />
K אאאאא<br />
- ٩٦ -
אא <br />
אא<br />
אא<br />
٢٣٧<br />
א <br />
א <br />
PB = PE = 1/2 erfc (<br />
EB / NO )<br />
אא (Performance) :<br />
= 1/2 erfc ( c Tb / No<br />
* )<br />
(21-3)<br />
= 1/2 erfc ( v Tb / 2No<br />
2<br />
)<br />
(BER)(Eb/No <br />
PB) אאאא<br />
(22-3)<br />
•<br />
•<br />
E23-3F<br />
- ٩٧ -
אא <br />
אא<br />
אא<br />
٢٣٧<br />
א <br />
א <br />
: (QPSK)אאא<br />
Quadrature phase shift keying<br />
<br />
אאא(QPSK)E١<br />
אאK<br />
א (BPSK) (QPSK) E٢<br />
: א<br />
VQPSK = UiVcosωct + U Q Vsinωct<br />
(٢٢-3)<br />
W <br />
(I)אא(BPSK)אאא J<br />
(Q)א(BPSK)אאא J<br />
Wאאא(V QPSK)אא J<br />
<br />
UQV<br />
VQPSK=V<br />
2<br />
<br />
<br />
<br />
UIV<br />
<br />
<br />
│VQPSK │= (U i V) 2 + (U Q V) 2 = 2 v 2 = V 2 (23-3)<br />
<br />
- ٩٨ -
אא <br />
אא<br />
אא<br />
٢٣٧<br />
א <br />
א <br />
W(47-3)א(46-3)אE٣<br />
= cosΦcoswet + sinΦsinwet<br />
= cos(ω c t-Φ )<br />
cos(ωct – Φ)<br />
2<br />
VQPSK = V<br />
:<br />
W א<br />
حيث إن<br />
אאא - Φ<br />
Φ = tan -1 UQ<br />
UI<br />
(24-3)<br />
(π / 4 , 3π / 4 , 5π / 4 , 7π / 4) אא<br />
Φ<br />
אאאאא(UI,UQ) (1-3)אא<br />
Kא(QPSK)EΦFאאא<br />
VQPSK (eq. 72) VQPSK (eq. 74) Phasor t<br />
s<br />
Transmitted<br />
bite<br />
Vcosωct+vsinωct v 2 cos(ωct- π /4)<br />
UI<br />
UQ<br />
Φ=45 1 1<br />
-<br />
vcosωct+vsinωct<br />
v 2 cos(ωct-3 π /4)<br />
Φ=135<br />
-1 1<br />
-vcosωct-vsinωct v 2 cos(ωct-5 π /4)<br />
Φ=225<br />
-1 -1<br />
-vcosωct-vsinωct v 2 cos(ωct-7 π /4) Φ=315 1 -1<br />
E1-3F<br />
- ٩٩ -
אא <br />
אא<br />
אא<br />
٢٣٧<br />
א <br />
א <br />
- ١٠٠ -<br />
Wאא<br />
Wאא(PSK)(Rs)אE<br />
<br />
R b<br />
Rs = symbols/s<br />
N<br />
360<br />
P = =<br />
M<br />
W<br />
אא JRb<br />
א JN<br />
אאאאE<br />
<br />
M = 2 N symbols<br />
C = B log 2 M<br />
אאאאE<br />
<br />
2 π<br />
rad<br />
M<br />
אאאE<br />
<br />
<br />
<br />
W<br />
אא JB<br />
<br />
W(S/N)אאא<br />
((PCM)א)<br />
WאאאאאאE١<br />
W(BER)אאE<br />
א(Thermal noise)אאאאאא<br />
Kאא<br />
W(S/N)אאE<br />
(PCM)
אא <br />
אא<br />
אא<br />
٢٣٧<br />
א <br />
א <br />
W<br />
(BER)אWאאא J<br />
W(Quantization noise)א J<br />
Wא<br />
<br />
V<br />
*<br />
( S / N )<br />
or<br />
E b<br />
No<br />
( S /N) Q = 2 2N = M 2 W<br />
Kא JM<br />
Kאאא JN<br />
<br />
אאאאאאאE٢<br />
PCM<br />
RF mixer IF detector * D/A * LP F<br />
P B<br />
ASK,FSK,PSK<br />
א(PCM)אאא<br />
( S / N )<br />
אאW <br />
<br />
<br />
<br />
<br />
- ١٠١ -
אא <br />
אא<br />
אא<br />
٢٣٧<br />
א <br />
א <br />
<br />
: 6-3<br />
200fw (200x10 -15 W).אאאאא<br />
אא(300K)אאא<br />
K(425K)<br />
<br />
(PCM)אאא<br />
Wא(2Mbit/sec)EbitF<br />
(PSK)אE<br />
(ASK)אE<br />
(ASK)אאאE<br />
( QPSK) آشف ترابطي E<br />
- ١٠٢ -
אא <br />
אא<br />
٢٣٧<br />
א <br />
א <br />
אא <br />
<br />
1. Ashok Ambardar, ‘Analog and Digital Signal Processing’, Thomson Learning Inc, 1999.<br />
2. John B. Anderson, ‘Digital Transmission Engineering’, Prentice Hall, 1999.<br />
3. A.B.Carlson, ‘Communication Systems’ McGraw-Hill, 1992.<br />
4. Simon Haykin: ‘Communication Systems’, 4th Edition, Wiley & Sons, 2001.<br />
5. Simon Haykin and Barry Van Veen: ‘Signals and Systems’, John Willey & Sons, Inc, 1999.<br />
6. Simon Haykins, ‘Digital Communication’, John Wiley, 2001.<br />
7. B.P.Lathi, ‘Analog and Digital Communication Systems’, PHI, 1992.<br />
8. Douglas K. Lindner, ‘Signals and Systems’, McGraw-Hill International, 1999.<br />
9. John Pearson : ‘Basic Communication Theory’, Prentice Hall, 2000<br />
10. J. Proakis: ‘Digital Communications’, McGraw Hill, 1995.<br />
11. J. Proakis and M. Salehi: ‘Contemporary Communication Systems Using<br />
MATLAB’, Bookware Companion Series, PWS Publishing, 1998.<br />
12. Proakis, ‘Digital Communication’, McGraw-Hill, 1992.<br />
13. Martin Roben: ‘Analog and Digital Communication Systems’, 4 th Edition, Prentice Hall, 1998<br />
14. K.Sam Shanmugam: ‘Digital and Analog Communication Systems’, John Wiley, 1985.<br />
15. Bernard Sklar: ‘Digital Communications, Fundamentals and Applications’, Second Edition,<br />
Prentice Hall, 2001.<br />
16. Taub & Schilling: ‘Principles of Communication’, McGraw-Hill Publication, 1990.<br />
17. Wayne Tomasi: ‘Advanced Electronic Communication Systems’, Prentice Hall, 2001<br />
18. Rodger E. Ziemer and Roger L. Peterson: ‘Introduction to Digital Communication’,<br />
2nd Edition, Prentice-Hall, 2001.<br />
19. Roger E. Zeimer et al.: ‘Signals and Systems, Continuous and Discrete’, McMillan, 2 nd Edition,<br />
1990.<br />
- ١٠٣ -
א <br />
אא<br />
٢٣٧<br />
א <br />
א <br />
א <br />
<br />
............................................................................................................<br />
............................................................................................................<br />
אאWא .................................................................................... ١<br />
٢ ..................................................................................Wא١ J١<br />
٥ ...................................................................................EAliasingFא٢ J١<br />
٦ .............................................................ETypes of samplingFאW٣ J١<br />
١١ .............................................................. אא٤ J١<br />
١٤ ..................................אאאאאאא٥ J١<br />
٢٤ ........................................................................ אא٦ J١<br />
٣٠ ..................... אאאא٧ J١<br />
אאWאא............................................................................. ٣٢<br />
٣٣ .......................................................................אאא١–٢<br />
٤٩ ......................................................................................... א٢–٢<br />
٥٩ ..................................... PCM/TDMאאא٣–٢<br />
٦٦ ......................................................................................... ٤–٢<br />
אאWאא ......................................................................... ٧١<br />
٧٢ .......................................(Baud rate)א(bit rate)אא1-3<br />
٧٣ .................................................................W(ASK)אא2-3<br />
٨٣ ...........................................................................אא3-3<br />
٩٠ ........................................................................... אא4-3<br />
אא..................................................................................................... ١٠٣<br />
- ١٠٤ -
אאאאאא<br />
אאFאEא <br />
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