א
א
א
Create successful ePaper yourself
Turn your PDF publications into a flip-book with our unique Google optimized e-Paper software.
אאא <br />
المؤسسة العامة للتعليم الفني والتدريب المهني<br />
אאאא<br />
א<br />
א אא<br />
٢٣٧
אא<br />
٢٣٧<br />
א <br />
א <br />
<br />
א،אאW،، <br />
אאאאאאאאאא<br />
אאאאאא،אאא<br />
אאאאא<br />
אאאאאאא<br />
Kאא<br />
אאאאאאא<br />
א،אאא<br />
אאאאאאאא،<br />
אא،א אא <br />
אאאאאאאאאאאא<br />
אאא،א<br />
א،אאK <br />
? א ??א א ? א א <br />
Kאאאאאאא<br />
אאאאאאא<br />
،א،אאאא<br />
Kאאאאא<br />
Kאאאאא<br />
אאאא
אא<br />
٢٣٧<br />
א <br />
א <br />
<br />
<br />
Kאאאאאאא<br />
אאאא،<br />
אאא א אאא אא <br />
<br />
אאK אאא <br />
אאאאא<br />
אKאא<br />
Kאא،אא<br />
<br />
Kא אאאאאאא<br />
אאא א<br />
W<br />
אאאאא J<br />
אאאאא، <br />
אאאאא אאאא J<br />
<br />
J<br />
E>אFאאאא J<br />
אאאאאאאאא<br />
Kא J<br />
<br />
א אאא<br />
KאאאKא
אא<br />
٢٣٧<br />
א <br />
א <br />
Kאאאא<br />
W<br />
אא •<br />
אאא •<br />
א •<br />
אאא •<br />
•<br />
אאE5V٠Fאא<br />
אE١٠F אאא <br />
١٠אאא Kאא <br />
Kאא<br />
אErepeatersFאאאאאא<br />
אאאאאK <br />
•<br />
Wאא<br />
אאאא •<br />
• אאאאK <br />
<br />
אא אאא<br />
א<br />
אא Kאאאא אאאא<br />
אא א،א<br />
אאאK <br />
<br />
Kאאאאאא<br />
אא א،א<br />
אK<br />
אא אאא،<br />
Kאא
אא<br />
٢٣٧<br />
א <br />
א <br />
אאKאאא<br />
Wא<br />
אאWא J<br />
אאWאא J<br />
אאWאא J<br />
<br />
אאאאאא<br />
א J<br />
א J<br />
Kא J<br />
<br />
אאא<br />
א J<br />
J<br />
אאאא אא<br />
אאאאא אאאא<br />
Eאא Fאאא<br />
،<br />
WKאאא<br />
אאא J<br />
אאא J<br />
<br />
W،אאאא<br />
אאא J<br />
אאא J<br />
אאא J
אא<br />
٢٣٧<br />
א <br />
א <br />
אאאאאאאא אא<br />
Kאא<br />
<br />
EאFא<br />
WאאKאאא<br />
א،אאא אאאא J<br />
אאאא،א<br />
אא אאאא<br />
J<br />
אא אא <br />
אאא<br />
אאא<br />
<br />
Kאאאאא<br />
אאאאאKאאאא א <br />
א אאא א<br />
Kאאאאאא<br />
،א<br />
אאאא، אאאאא<br />
<br />
אאאאאאאK<br />
א،אאא<br />
Kאא<br />
אאאא
١ א<br />
אאא <br />
المؤسسة العامة للتعليم الفني والتدريب المهني<br />
אאאא<br />
אא<br />
א<br />
א
אא <br />
א<br />
אא<br />
٢٣٧<br />
א <br />
א <br />
אאWא <br />
Sampling<br />
<br />
אאWאאאאאא<br />
אאאאאאFאא<br />
אאאאKE<br />
אאאKאאאא<br />
אאאא<br />
אKאאאא<br />
Kאא<br />
<br />
אאWאאאK٪٩٠ <br />
<br />
אא١٢W <br />
<br />
אאWאאKאאאK <br />
<br />
KאאאאאWאא<br />
<br />
- ١ -
אא <br />
א<br />
אא<br />
٢٣٧<br />
א <br />
א <br />
Wא١ J١<br />
ESampling Theorem or Shannon TheoremF<br />
،2fmfs fm אאאא<br />
Kאאאא<br />
אאאא،<br />
אאא(base band signal)אא<br />
Vs(t) = V(t) * P(t)<br />
- ٢ -<br />
Wאא<br />
E١ J١Ffs ≥ 2fm<br />
אאfsW<br />
E٢ J١F TsZ1/fs<br />
אאfm<br />
Tsא<br />
WאאאאW<br />
א<br />
1/2fmאאא<br />
Kאאאא E٣<br />
<br />
،אאאא(aliasing error)א<br />
Nyquist Fאא٢fmא<br />
f s min = f N = 2f m<br />
( ٣-١) T N = 1 / 2f m<br />
E١<br />
E٢<br />
،Efrequency<br />
ENyquist frequencyF f N<br />
W<br />
KאT N <br />
אP(t)V(t)אאא<br />
E ٣-١)<br />
אאsignalFVs(t) J١אאKEsampled K١
אא <br />
א<br />
אא<br />
٢٣٧<br />
א <br />
א <br />
V(t)<br />
א<br />
(אא)<br />
א<br />
(א)<br />
V(f)<br />
<br />
<br />
<br />
(a)<br />
- f m 0 f m f<br />
(a / )<br />
P(t) = a 0 + ∑a n cos 2π nf s t<br />
P(f)<br />
2f s 3f s<br />
- f s<br />
T s 2T s …… t<br />
(b)<br />
V S (t) = V(t) P(t)<br />
= V(t) a 0 + ∑a n V(t) cos(2π nf s t)<br />
(b / )<br />
V S (f) = a 0 V(f) + ∑a n V(f – nf s )<br />
(c)<br />
-f m f m f s -f m f s +f m 2f s<br />
(c / )<br />
אW١-١אאאא <br />
3f s<br />
- ٣ -
אא <br />
א<br />
אא<br />
٢٣٧<br />
א <br />
א <br />
sampleאאF (gating)א<br />
K١ J١אKEא hold א<br />
<br />
אWאאאאאK <br />
–f m f m אV(t)אאאאV(f)<br />
E١<br />
<br />
(٤-١)<br />
(٥-١)<br />
<br />
אJ١ אאW٢ <br />
- ٤ -<br />
P(t)<br />
P(t) = a 0 + ∑ a n cos 2π n f s t<br />
<br />
א<br />
cos(2π nf s t)V(t)א<br />
אא٥–١א<br />
Wאאnאnfsאא،cos(2π nf s t)א<br />
(٦-١)<br />
V S (t) = S(t) P(t)<br />
= a 0 V(t) + ∑a n V(t) cos(2π nf s t)<br />
V S (f) = a 0 V(f) + ∑a n V(f – nf s )<br />
E٢<br />
E٣<br />
E٤<br />
<br />
<br />
<br />
<br />
E١–١אאFW<br />
אאאאJ١ אFאא١<br />
אא אa 0 V(t)a 0 Ebase band signal oranalog signal<br />
אאאאJ١ K٥<br />
<br />
fs ≥ אאאאאא2fm، E١
אא <br />
א<br />
אא<br />
٢٣٧<br />
א <br />
א <br />
،א<br />
אאאאא<br />
E٢<br />
α 0 V(t)אאא<br />
E٣<br />
א<br />
V(f)FאfsאTsא<br />
אאאE<br />
אfsאTsא،<br />
אא،EאאאV(f)F<br />
אfs ═2fmאKא<br />
Kאא<br />
•<br />
•<br />
<br />
<br />
EAliasingFא٢ J١<br />
אאא،EFאאאאאאא<br />
אאאJ١ אאא،٣<br />
K<br />
אאאאאאאאא<br />
f s < 2f m<br />
אאאאאא<br />
KEAliasing errorsFא،K<br />
<br />
<br />
אW٣–١אFאאאאKE <br />
<br />
- ٥ -
אא <br />
א<br />
אא<br />
٢٣٧<br />
א <br />
א <br />
،אא<br />
Elow pass filter LPFFאאא E١<br />
KEanti-aliasing filterFאא<br />
<br />
f max אאEcut off frequency f cut off Fא<br />
( ٧-١)<br />
f cut off ≤ f max<br />
א، Nאאאא<br />
E٢<br />
<br />
א t p<br />
،אאאאאf s <br />
E٨ J١F<br />
N = f s t p = t p / T s<br />
<br />
•<br />
<br />
<br />
ETypes of samplingFאW٣ J١<br />
Kא<br />
<br />
EIdeal samplingFWאאאW١ J٣ J١<br />
אאKEunit weighted pulsesFאא<br />
K٤–١אאKEPAMFא<br />
- ٦ -
אא <br />
א<br />
אא<br />
٢٣٧<br />
א <br />
א <br />
١אאאא<br />
V(f)<br />
אאאאא<br />
V (t)<br />
<br />
<br />
<br />
-fm<br />
fm<br />
f<br />
t<br />
1<br />
P( f ) = ∑δ ( f − nfs)<br />
T<br />
Ρδ<br />
() t = δ ( t − nTs)<br />
∑ +∞<br />
n=<br />
−∞<br />
f<br />
-fs 0 fs 2fs<br />
3fs<br />
1<br />
Vs ( f ) = ∑V<br />
( f − nfs)<br />
T<br />
Ts<br />
Vs(t) = V(t) Pδ(t)<br />
t<br />
-fm fm fs-fm fs+fm ………………….<br />
t<br />
אJ١ אאאW٤ <br />
<br />
<br />
ENatural samplingFאאא٢ J٣ J١<br />
אאאאא<br />
אKאJ١ Kא٥ <br />
<br />
- ٧ -
אא <br />
א<br />
אא<br />
٢٣٧<br />
א <br />
א <br />
<br />
אJ١ אאW5 <br />
Wא<br />
אEFETFאאW E١<br />
א E٢<br />
Kאא، E٣<br />
<br />
Eflat-top samplingFאאא٣ J٣ J١<br />
אאאאא<br />
KE٥ J١אFאאא<br />
sample Fאאאאאא<br />
KE7 J١אFKEand hold circuit<br />
<br />
<br />
- ٨ -
אא <br />
א<br />
אא<br />
٢٣٧<br />
א <br />
א <br />
אאאא ١אאאא<br />
V(f)<br />
V(t)<br />
א<br />
-fm<br />
fm<br />
t<br />
τ<br />
P(f) = ∑ Sa( πfτ<br />
) δ ( f − nfs)<br />
T<br />
P(t)<br />
τ<br />
X<br />
X<br />
∑<br />
a V ( f ) + anV ( )<br />
0<br />
f<br />
τ<br />
Vs(<br />
f ) =<br />
T<br />
=<br />
+∞<br />
∑<br />
n=−∞<br />
α V(f)<br />
0<br />
⎛ nπτ<br />
⎞<br />
Sa⎜<br />
⎟V<br />
( f − nfs)<br />
⎝ T ⎠<br />
+<br />
+∞<br />
∑<br />
-∞<br />
α<br />
n<br />
V(f-nfs)<br />
Vs(t)=P(t) * V(t)<br />
+3fs<br />
-fs -fm fm fs<br />
אJ١ אW6 <br />
<br />
<br />
<br />
- ٩ -
אא <br />
א<br />
אא<br />
٢٣٧<br />
א <br />
א <br />
<br />
אJ١ אאאאW7 <br />
<br />
Wא<br />
אEFETFאא E١<br />
א E٢<br />
Kאא، E٣<br />
אCאEsampleFאEFETFאאא E٤<br />
KEholdF<br />
אK٧ J١אאא<br />
אאאאאאא<br />
אK <br />
<br />
<br />
- ١٠ -
אא <br />
א<br />
אא<br />
٢٣٧<br />
א <br />
א <br />
<br />
אJ١ אאאW8 <br />
אא٤ J١<br />
Ebase bandFאאPAMאא E١<br />
אאFKfsאאאאאא<br />
א sin c(<br />
x)<br />
=<br />
sin x<br />
x<br />
E٤ J١<br />
אאאאאא<br />
،אאאאKx<br />
Wאאא E٣<br />
<br />
B T =<br />
E٩ J١F <br />
E٢<br />
א<br />
cut off FאאאאK1א<br />
K1<br />
τ<br />
KEfrequency fcut off<br />
<br />
- ١١ -
אF<br />
אא <br />
א<br />
אא<br />
٢٣٧<br />
א <br />
א <br />
אאWPAM <br />
אאאPCM<br />
TDMאא<br />
•<br />
•<br />
<br />
<br />
١ J١<br />
fs = אV(t)<br />
Kτ = 40µs،5KHz<br />
EאאFאאEאF<br />
KK1 = 1.0K1 = 0.5אאEF<br />
Kא 25 KHz אאEF<br />
<br />
<br />
٢ J١<br />
K8KHz٠אV(t)<br />
אאאאאE<br />
אאאEF<br />
<br />
٣ J١<br />
א١ J١אאאV(t)<br />
אאK6KHz <br />
אאאאאאWF<br />
אK <br />
<br />
<br />
<br />
- ١٢ -
אא <br />
א<br />
אא<br />
٢٣٧<br />
א <br />
א <br />
<br />
٤ J١<br />
K4 kHz dc،אV(t)<br />
אKאאאא<br />
אאK٪٥٠ <br />
אEאF<br />
אאEF<br />
<br />
٥ J١<br />
KE10000 HzFא١٠٠٠٠א<br />
אאאFאא،אא<br />
K4KHzEguard bandאאא<br />
<br />
٦ J١<br />
K٪٢٥fm fs- fm،fm،fs=9KHz<br />
<br />
٧ J١<br />
K0.25ms 500 Hzא<br />
אאאא18KHzאK <br />
- ١٣ -
אא <br />
א<br />
אא<br />
٢٣٧<br />
א <br />
א <br />
٨ J١<br />
K2 KHz1 KHz<br />
אאאאKא0.1ms<br />
K35KHz<br />
אאאאאאא٥ J١<br />
(TDM of PAM signals)<br />
אאאאWאאאא<br />
אKאאKאא<br />
KEsequentiallyFא<br />
אאW אאאאאאא<br />
<br />
Kאא<br />
<br />
<br />
אJ١ אW٩ <br />
- ١٤ -<br />
<br />
אW <br />
،TsE>אFא E١<br />
Kאא،אאא<br />
،אאאאאא<br />
KKKKאא،אאאאאא<br />
،EFאאאא<br />
Kאא،אאא E٥<br />
<br />
E٢<br />
E٣<br />
E٤
אא <br />
א<br />
אא<br />
٢٣٧<br />
א <br />
א <br />
Wאא١ J٥ J١<br />
אאאאW<br />
אא E١F<br />
KV2(t)V1(t)א٩ J١אא<br />
<br />
E<br />
<br />
אJ١ אאW١٠ <br />
<br />
א٢١אא<br />
- ١٥ -<br />
אאאא،<br />
KETsFא<br />
Kאאאאא<br />
<br />
•<br />
•<br />
אאאE٢F<br />
signal אאאא<br />
E>אFKsignal #4#1<br />
אאEcommutatorFא<br />
KאEdecommutatorF<br />
،אאאא<br />
11 J١א،אאא<br />
אאK<br />
•<br />
•
אא <br />
א<br />
אא<br />
٢٣٧<br />
א <br />
א <br />
<br />
<br />
<br />
١-١١ : الشكل تجميع أآثر من إشارتين بطريقة التقسيم الزمني وباستعمال جامع ومفكك<br />
<br />
אאאאאאאE٣F<br />
אEsampling theoremFא<br />
(f N = 2fm).<br />
אאאאאאאאE٤F<br />
א<br />
٧א٧١١ J١אE٥F<br />
אאא<br />
אאאאTs/7 τ=<br />
אאKאאאK <br />
Kאאאאאא<br />
אאאKאאE٦F<br />
K١٢ J١אאאא<br />
- ١٦ -
אא <br />
א<br />
אא<br />
٢٣٧<br />
א <br />
א <br />
<br />
אJ١ אא٧W١٢ <br />
אא<br />
אאאא،אאאאE١F<br />
τ<br />
K١ אא<br />
Tframe<br />
Nא B<br />
=<br />
0.5<br />
τ<br />
<br />
אאאE١F<br />
fs = f N = 2fm<br />
אא<br />
א<br />
אאא<br />
k =<br />
Ts<br />
אאאW<br />
τ<br />
•<br />
•<br />
•<br />
•<br />
<br />
אJ١ אW١٣ Kאאאk <br />
- ١٧ -
אא <br />
א<br />
אא<br />
٢٣٧<br />
א <br />
א <br />
Wא<br />
fmא،k EF<br />
אאאא<br />
K<br />
Wאאא E F<br />
1<br />
( ١٠-١) fs = 2fm, Ts = 2fm , Tframe =<br />
1<br />
2fm<br />
אאk<br />
( ١١-١) τ =<br />
Tframe<br />
k<br />
E<br />
א<br />
<br />
0.5 0.5<br />
0.5<br />
( ١٢-١) B =<br />
τ<br />
= Tframe = =<br />
Ts/k<br />
k<br />
0.5k<br />
Ts<br />
<br />
E<br />
F<br />
F<br />
0.5k<br />
= 1/2fm = 0.5 k (2fm) = k X fm<br />
B T = k fm for the ration B =<br />
1<br />
τ<br />
( ١٣-١) BT = 2k fm.<br />
= EאFאאאא<br />
KאאאXאאא<br />
<br />
- ١٨ -
אא <br />
א<br />
אא<br />
٢٣٧<br />
א <br />
א <br />
،אאאא،אאאא<br />
W،אאאאא<br />
E١٤ J١FBT = L X fm<br />
L = number of spaces + sync + data pulses<br />
fs = 2fm J<br />
W<br />
•<br />
•<br />
<br />
<br />
fs > 2fm<br />
E١٥ J١FBT = L x<br />
Fs<br />
2<br />
<br />
W٩ J١א<br />
אאאאא PAMא٧<br />
Kאא،BW = 1 kHz<br />
- ١٩ -
אא <br />
א<br />
אא<br />
٢٣٧<br />
א <br />
א <br />
<br />
אJ١ PAMא٧W١٠ אאאאא<br />
Wאא،١٢ J١אא<br />
אJ١ אאא٧١٤ <br />
<br />
Fs = 1.25 fN<br />
אEאאא <br />
אא،אאאE<br />
אאK <br />
אאאאאW E<br />
(Multiplexing of dissimilar channels)<br />
Kאאאאאאא<br />
אאאאאאאcommutationF KEsub and super<br />
<br />
<br />
<br />
- ٢٠ -
אא <br />
א<br />
אא<br />
٢٣٧<br />
א <br />
א <br />
אאא <br />
אאאא<br />
<br />
Efixed rateFאא<br />
אאאא<br />
אאאא<br />
אאא<br />
Kאאאא<br />
K16 kHz،15.5 kHz8 kHz<br />
Wאאא<br />
Wאאאאאא<br />
אאאא<br />
80 kHzא J<br />
40 kHzא J<br />
10 kHz١٨ J<br />
1250 Hz א ٨ J<br />
625 Hz١٦ J<br />
•<br />
•<br />
•<br />
<br />
K١٤ J١אא١٦אא<br />
<br />
•<br />
•<br />
E١<br />
E٢<br />
<br />
אJ١ א٣٢אאאאW١٥ <br />
<br />
- ٢١ -
אא <br />
א<br />
אא<br />
٢٣٧<br />
א <br />
א <br />
؟א<br />
Wא<br />
אאאאK٦٢٥א E<br />
א١٠٠٠٠אאאא E<br />
אאאאאא،<br />
،אאאא10 kHz١٨א J<br />
א<br />
،אא٤40 kHzא J<br />
<br />
،אא٤40 kHzא J<br />
<br />
،אא880 kHzא J<br />
<br />
،אא٤40 kHzא J<br />
<br />
،א10 kHzאאאאאא<br />
<br />
،א1250 Hzאאא J<br />
K16625 Hzאאא J<br />
<br />
א1250 Hzאאאא<br />
K0.1 msאא ،א١٢٥٠<br />
،א625א625 Hzאאא<br />
K0.2 msאא<br />
<br />
E<br />
- ٢٢ -
אא <br />
א<br />
אא<br />
٢٣٧<br />
א <br />
א <br />
W١١ J١<br />
2 τאא٦PAM/TDM <br />
אKτאאאKτ<br />
אאFאKE> <br />
1 אאאאא<br />
KkHz<br />
<br />
<br />
אJ١ Kאא٦١٦<br />
Kfs = 1.5 fNאאEF<br />
אא،אאאאאא<br />
א<br />
<br />
W١٢ J١<br />
Kfs = 2fN١١ J١א<br />
- ٢٣ -
אא <br />
א<br />
אא<br />
٢٣٧<br />
א <br />
א <br />
- ٢٤ -<br />
אא٦ J١<br />
(Pulse Analog Modulation)<br />
W١ J٦ J١<br />
אא:א<br />
EpositionFאEduration or widthFאאEamplitudeFא<br />
(Pulse Amplitude Modulation: PAM)א<br />
אEאאאאאFאא<br />
א KאאאSTs(t) <br />
Pulse height = V α Vs<br />
tאאא<br />
KאVα<br />
(Pulse Width Modulation: PWM)א<br />
<br />
אEאאאאאFא<br />
KאאאSTs(t)<br />
Pulse width = τα Vs<br />
א<br />
<br />
tאאאVs<br />
Kא τα <br />
(Pulse Position Modulation: PPM)א<br />
אאאאFאא<br />
אאאאEאא אאSTs(t)<br />
Pulse position = td Vs<br />
Kא<br />
tאאאVs<br />
Kא td <br />
<br />
Kאאאא١٦ J١א<br />
אK <br />
•<br />
•<br />
•
אא <br />
א<br />
אא<br />
٢٣٧<br />
א <br />
א <br />
<br />
<br />
אJ١ Kאאאא١٧ <br />
<br />
:אא<br />
•<br />
WאאEא<br />
אאאאא<br />
אאאאאא<br />
אאאאא<br />
o<br />
o<br />
WאE<br />
Kאא<br />
o<br />
<br />
<br />
<br />
<br />
א٢ J٦ J١<br />
אEאPAM) (Pulse Amplitude Modulation:<br />
אEאאאאאFאא<br />
א KאאאSTs(t) <br />
א،א •<br />
<br />
א E<br />
(Pulse Width Modulation: PWM)<br />
(Pulse Duration Modulation: PDM)<br />
- ٢٥ -
אא <br />
א<br />
אא<br />
٢٣٧<br />
א <br />
א <br />
אאSTs(t)<br />
אאEFא<br />
،א،א<br />
،א،א<br />
Kא<br />
אאא<br />
Kא<br />
•<br />
•<br />
•<br />
Kאא١٨ J١א<br />
<br />
אJ١ Kא١٨ <br />
Wא<br />
א،STs(t)=1،אאא E١<br />
<br />
אאא،STs(t)=2 E٢<br />
،STs(t)=1<br />
Kאאא E٣<br />
אאאאאJ١ ١٩<br />
<br />
אJ١ אאא١٩ <br />
<br />
،אאאW<br />
אאאאK <br />
<br />
- ٢٦ -
אא <br />
א<br />
אא<br />
٢٣٧<br />
א <br />
א <br />
א E<br />
(Pulse Position Modulation: PPM)<br />
אאSTs(t) אאEFא<br />
אאא،א<br />
אאא<br />
אאא<br />
אא<br />
אאאאאא<br />
KאEאFאא<br />
אאא<br />
אW<br />
אאאאאא<br />
Kאאא<br />
o<br />
o<br />
Kא<br />
•<br />
•<br />
•<br />
•<br />
Wאאא<br />
אאא٢١ J١אKאאאא٢٠ J١א<br />
WאאKאא<br />
S1(t)אאPAM<br />
S2(t)אEramp generatorFאאא<br />
S3(t) = S2(t) + S1(t)<br />
S3(t)<br />
אאא<br />
S2(t) S1(t)<br />
אאS3(t)<br />
Vcc אא(comparator)אEsaw toothFאא<br />
. S4(t)<br />
PWMאאאאא٠<br />
S3(t) > Vref <br />
ES5(t))אאאאEdifferentiatorF<br />
KS6(t)PPM<br />
K١<br />
K٢<br />
K٣<br />
K٤<br />
K٥<br />
K٦<br />
- ٢٧ -
אא <br />
א<br />
אא<br />
٢٣٧<br />
א <br />
א <br />
<br />
Kאאאא٢٠ J١א<br />
- ٢٨ -
אא <br />
א<br />
אא<br />
٢٣٧<br />
א <br />
א <br />
<br />
אJ١ Kאאאאא٢١ <br />
- ٢٩ -
אא <br />
א<br />
אא<br />
٢٣٧<br />
א <br />
א <br />
אאאא٧ J١<br />
(Demodulation of PAM and PWM and PPM)<br />
Wאא١ J٧ J١<br />
،ELPFFאאא،א<br />
E١<br />
<br />
אJ١ KאPAMאאא٢٢ <br />
<br />
א א ،EinstantaneousFא E٢<br />
אEshaped transfer characteristicsFא <br />
،EequalizerF<br />
<br />
<br />
אJ١ KאPAMאאא٢٣ <br />
אאא<br />
K PAM PAM אא<br />
EintegratorFאא<br />
אא٢ J٧ J١<br />
PAM<br />
E٣<br />
א PWM إلى<br />
Esample pointFאEintegrationFא<br />
אאKא،אא،<br />
•<br />
E<br />
- ٣٠ -
אא <br />
א<br />
אא<br />
٢٣٧<br />
א <br />
א <br />
אאאאאאא<br />
،א<br />
א Kא ٢٣ J١ א<br />
אW<br />
אאאא E<br />
א <br />
KאPAMא E<br />
•<br />
•<br />
אא٣ J٧ J١<br />
אא<br />
אאא<br />
،PWMאאPPM א<br />
KPAM إلى PWM אאא<br />
٢٤ J١אא<br />
•<br />
•<br />
•<br />
•<br />
PWM<br />
Ts 2Ts 3Ts 4T<br />
t<br />
PPM<br />
t<br />
PAM<br />
Ts 2Ts 3Ts 4T<br />
t<br />
אJ١ KPAMPPMPWMא٢٤<br />
- ٣١ -
אא ٢<br />
אאא <br />
المؤسسة العامة للتعليم الفني والتدريب المهني<br />
אאאא<br />
אא<br />
אא<br />
א
אא <br />
אא <br />
אא<br />
٢٣٧<br />
א <br />
א <br />
אאWאא <br />
Digital modulation<br />
<br />
אאWאאאאאאאאא<br />
KאאאKEאאאאF<br />
אאאאאK<br />
אאאKאא<br />
אאאאK <br />
<br />
אאWאאאK٪٩٠ <br />
<br />
אא١٥W <br />
<br />
אאWאא <br />
<br />
אאאאאאאWאא<br />
אK <br />
<br />
- ٣٢ -
אא <br />
אא <br />
אא<br />
٢٣٧<br />
א <br />
א <br />
אאא١–٢<br />
<br />
אאWאאEF<br />
אאKאאאאאאא<br />
Kאאא<br />
<br />
Kאאאאא١–٢א<br />
<br />
١א–א؟ J١ J٢<br />
אW <br />
אאאEFאאאא K١<br />
אאאאאאאא<br />
،<br />
אאאא،אאא K٢<br />
אאאאאא<br />
،<br />
אאאאא K٣<br />
،א<br />
<br />
אאאא<br />
Kאאאאאאא<br />
אאאאאא<br />
Kאאאאא<br />
<br />
- ٣٣ -
אא <br />
אא <br />
אא<br />
٢٣٧<br />
א <br />
א <br />
<br />
<br />
אW١–٢אאא<br />
אW <br />
Kא،<br />
<br />
<br />
Wאא٢ J١ J٢<br />
Band Fאאאאאאא K١<br />
Ecut frequency fmFאאאאאא<br />
- ٣٤ -<br />
،fs≥f N <br />
Epass filter<br />
fsא K٢<br />
אEPCMFאEPAMFאא K٣<br />
ECode WordFאESampleFEEncoderF<br />
KE٨F
אא <br />
אא <br />
אא<br />
٢٣٧<br />
א <br />
א <br />
FאאWא–<br />
K٤<br />
،אאEquantization levels<br />
EאFE١٠ J٠Fאא<br />
،Equantization intervalFאאא<br />
،אאn2n٢א<br />
٠אאאא E28F٢٥٦אn=8<br />
K٢٥٥<br />
٠א،אWא–<br />
אE٢٥٥FאאאאאEF<br />
،ECode WordFאאא<br />
<br />
K٥<br />
•<br />
•<br />
K٦<br />
אא٣ J١ J٢<br />
N،אא،אM<br />
،אא<br />
( ١ J2)……….M = 2 N <br />
WNאMאא<br />
(2-2)…….N = Log 2 M = 3.32 Log 10 M<br />
- ٣٥ -<br />
W١–٢<br />
M=٢٥٦Enormalized PCMFאא<br />
א <br />
N = log2256= log228=8 bit <br />
W٢–٢<br />
Kאא،א<br />
K٧אאא،א٦{٦٤<br />
128 = 27 = 2NEN=7Fא<br />
K١٠٠<br />
E١
אא <br />
אא <br />
אא<br />
٢٣٧<br />
א <br />
א <br />
<br />
١–٢<br />
N=100Nא<br />
<br />
٢–٢<br />
٨<br />
K٣<br />
<br />
אJ٢ אאW٢ <br />
<br />
אאאאאא E٢<br />
KELow Pass Filter LPFFא<br />
<br />
א٤ J١ J٢<br />
אאEPCMFא E١<br />
אsignalF FאאEAnalog PAM<br />
- ٣٦ -<br />
KEsignal<br />
Kfmאא E٢<br />
fN=2fm
אא <br />
אא <br />
אא<br />
٢٣٧<br />
א <br />
א <br />
fs=fN=2fmא<br />
Rb = Nfs = 2Nfmא<br />
BT = Rb = 2NfmWא<br />
W٣ J٢<br />
אאאא<br />
fm=4 KHZ, n=8<br />
א<br />
אא<br />
אאאאאconverterF ED/A<br />
،Equantization intervalFא<br />
<br />
٢–٢א<br />
א٥ J١ J٢<br />
K٧<br />
אW<br />
+V-Vאא<br />
V<br />
אV2 <br />
WאאאN<br />
2V<br />
(2-5) ……… ∆ = volts<br />
N<br />
2<br />
E١<br />
•<br />
•<br />
אא<br />
∆ 2v<br />
= / 2 =<br />
2 2n<br />
V<br />
2<br />
n<br />
volts <br />
(2-6)……………N Q = V 2 /2 2N<br />
אא<br />
watts<br />
אLא<br />
•<br />
•<br />
•<br />
- ٣٧ -
אא <br />
אא <br />
אא<br />
٢٣٧<br />
א <br />
א <br />
∴<br />
2<br />
V<br />
N<br />
( S SQ 2<br />
⎛ ⎞<br />
2<br />
) = = V ÷ ⎜ ⎟ = 2<br />
N<br />
Q<br />
NQ<br />
⎜<br />
⎝ 2<br />
∴<br />
2N<br />
(2-7)…………….. ( )<br />
N<br />
⎟<br />
⎠<br />
S 2<br />
N<br />
Q<br />
= 2<br />
<br />
אאאא<br />
אאKאא<br />
אא<br />
EcharacteristicFENon linear amplifierFאא<br />
Kאאא<br />
KאאאאאW<br />
Kאא٣–٢א<br />
<br />
<br />
- ٣٨ -
אF<br />
אא <br />
אא <br />
אא<br />
٢٣٧<br />
א <br />
א <br />
<br />
אJ٢ אא٣ <br />
<br />
א٦ J١ J٢<br />
EאFאא<br />
،אאאאא<br />
אאא<br />
אא<br />
א<br />
א<br />
Kא<br />
- ٣٩ -<br />
•<br />
•<br />
E١<br />
E٢<br />
E٣<br />
<br />
W٤ J٢<br />
אK<br />
אE<br />
١٠אEF<br />
אEF<br />
אLאEF<br />
PS/QN J<br />
N=10 bitSNR= 2 2N J<br />
40dBאאאEF
אא <br />
אא <br />
אא<br />
٢٣٧<br />
א <br />
א <br />
אאא٧ J١ J٢<br />
אאאא E١<br />
=<br />
⎛ Vi<br />
ln<br />
⎜1<br />
+ µ<br />
⎝ Vi<br />
max<br />
V<br />
(2-8)……… 0<br />
V0max<br />
ln(1 + µ )<br />
for Vi ≥ 0<br />
⎞<br />
⎟<br />
⎠<br />
<br />
אVi<br />
אV0<br />
אאVi max<br />
אאV0 max<br />
E٢٥٥F Ecompression parameterFאµ<br />
<br />
אW٤–٢אאא<br />
אאא<br />
א<br />
אאא<br />
(2-9)………..<br />
V<br />
ie<br />
V<br />
=<br />
µ<br />
i max<br />
⎡<br />
⎡<br />
Vr<br />
⎢<br />
0 max<br />
⎢ ⎣V<br />
( 1+<br />
µ )<br />
⎢<br />
⎣<br />
⎤<br />
⎥<br />
⎦<br />
⎤<br />
⎥ forV<br />
⎥<br />
⎦<br />
r<br />
≥ 0<br />
אW<br />
E٢<br />
E٣<br />
- ٤٠ -
אא <br />
אא <br />
אא<br />
٢٣٧<br />
א <br />
א <br />
<br />
אאאVie<br />
LאFאאאא E٤<br />
KEcodec: coder/decoder<br />
<br />
WA law (Europe) codec’א–א’<br />
⎛1+<br />
lg Ax ⎞<br />
V0 = V0 max<br />
⎜ ⎟sign<br />
1/A < X
אא <br />
אא <br />
אא<br />
٢٣٧<br />
א <br />
א <br />
אא٩ J١–٢<br />
<br />
אאא<br />
אאאא،א<br />
K١אאאאEnormalized valuesF<br />
normalizes I/P analog voltage =<br />
X (t) = Vi<br />
V fs<br />
V fs<br />
actual I/P analog voltage<br />
full - scale voltage of<br />
, where V<br />
fs =<br />
2.5, 5,10, 20 ....<br />
Wאאאא<br />
A/D converter<br />
⎡actual<br />
out put ⎤ ⎡normalized value⎤<br />
⎡<br />
⎤<br />
⎥ × full scale voltage<br />
⎢<br />
⎥ = ⎢<br />
⎢<br />
⎥<br />
⎣analog voltage⎦<br />
⎣of<br />
digital word ⎦ ⎣of<br />
D/A converter⎦<br />
V = X ( t)<br />
×<br />
o<br />
،אLא<br />
<br />
<br />
KאLא<br />
WאLאאא<br />
אאencodingF ١{٠٠{٠אאEunipolar <br />
אאencodingF J١{٠אאEbipolar <br />
KH١{٠<br />
٤אאאא<br />
K١٦٠<br />
<br />
- ٤٢ -
אא <br />
אא<br />
א <br />
אא <br />
٢٣٧<br />
א <br />
<br />
<br />
<br />
<br />
<br />
א<br />
א<br />
א<br />
7/8=0.875<br />
6/8=0.75<br />
5/8=0.625<br />
4/8=0.5<br />
3/8=0.375<br />
2/8=0.25<br />
1/8=0.125<br />
0<br />
-1/8=-0.125<br />
-2/8=-0.25<br />
-3/8=-0.375<br />
-4/8=-0.5<br />
-5/8=-0.625<br />
-6/8=-0.75<br />
-7/8=-0.875<br />
-8/8=-1<br />
15/16=0.9375<br />
14/16=0.875<br />
13/16=0.8125<br />
12/16=0.75<br />
11/16=0.6875<br />
10/16=0.625<br />
9/16=0.5625<br />
8/16=0.5<br />
7/16=0.4375<br />
6/16=0.375<br />
5/16=0.3125<br />
4/16=0.25<br />
3/16=0.1875<br />
2/16=0.125<br />
1/16=0.0625<br />
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 />
0<br />
<br />
1111<br />
1110<br />
1101<br />
1100<br />
1011<br />
1010<br />
1001<br />
1000<br />
0111<br />
0110<br />
0101<br />
0100<br />
0011<br />
0010<br />
0001<br />
0000<br />
<br />
אJ٢ W١אאאאאא <br />
K٤א<br />
<br />
אאא ١ J٩ J١ J٢<br />
EאאFאא E١<br />
∴the range of the normalized signal X ( t)<br />
is 0 ≤ X <<br />
J٢אאא∴<br />
N = 2<br />
4 =<br />
1אא<br />
١אא<br />
16٤<br />
אאאאאא١<br />
WאאE١{٠אאF١{٠٠{٠<br />
E٢<br />
<br />
- ٤٣ -
אא <br />
אא <br />
אא<br />
٢٣٧<br />
א <br />
א <br />
<br />
אא אאא <br />
אא<br />
<br />
EXnF<br />
<br />
0 =<br />
16<br />
8<br />
=<br />
16<br />
15 =<br />
16<br />
0<br />
0.5<br />
0.9375<br />
<br />
<br />
3 2 1<br />
0 × 2 + 0×<br />
2 + 0×<br />
2 + 0×<br />
1×<br />
2<br />
<br />
3<br />
1×<br />
2<br />
3<br />
+ 0 × 2<br />
+ 1×<br />
2<br />
2<br />
2<br />
+ 0 × 2<br />
+ 1×<br />
2<br />
1<br />
1<br />
+ 0 × 2<br />
+ 1×<br />
2<br />
0<br />
0<br />
2<br />
0<br />
= 8<br />
= 15<br />
0000<br />
1000<br />
LSBKKKKMSB<br />
1111<br />
<br />
אא١١١١<br />
א١{٠א<br />
E١٣ J٢FKKKKKKKKKKKKKKKKKK ∆ Xu<br />
אא<br />
1<br />
=<br />
2N<br />
E٣<br />
<br />
E١٤–٢FKKKKKKKKKKKKKKKKKK ∆Vu<br />
אא E٤<br />
V<br />
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 />
١Fא<br />
E<br />
1<br />
<br />
١<br />
٢<br />
٣<br />
٤<br />
٥<br />
٦<br />
٧<br />
א<br />
٨<br />
٩<br />
١٠<br />
١١<br />
١٢<br />
١٣<br />
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 />
<br />
٢٣<br />
<br />
٢٤<br />
•<br />
•<br />
•<br />
•<br />
•<br />
<br />
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 />
<br />
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 />
<br />
אJ٢ ٢٤אאאאאW١١ <br />
<br />
E32 Channel SystemFWEאאF٣٢٢ J٢ J٣ J٢<br />
אאECode WordsF ٣٢אE١<br />
אאK <br />
K31٠אא<br />
אאאE١٦FאE٠Fאא<br />
אאE٣١١٧١٥١Fאא<br />
٠<br />
<br />
א<br />
1<br />
١<br />
٢<br />
٣<br />
٤<br />
KKKKKKKKK<br />
١٣<br />
א<br />
١٤<br />
١٥<br />
Fאאא١٥<br />
٨E<br />
١٦<br />
<br />
א<br />
١٧<br />
KKKKKKKKK<br />
K<br />
٢٩<br />
٣٠<br />
•<br />
•<br />
٣١<br />
אאא١٥<br />
١٩٣Zא١H١٩٢Z٨х٢٤Wא<br />
EF<br />
٨<br />
Kא١٦٠א٣٠אאאא<br />
1<br />
١٢٥µs א<br />
8000<br />
Synchronization Fאאאאאאאא<br />
K١٦٠אאאEand signaling<br />
•<br />
•<br />
•<br />
- ٦٣ -
אא <br />
אא <br />
אא<br />
٢٣٧<br />
א <br />
א <br />
W٣٢א<br />
٨FאPCM٣٠אא<br />
E١٢٥µsFאE<br />
אאאאאא<br />
،אKאאא<br />
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 />
= = = 2<br />
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 />
<br />
<br />
٣٢אאאאאא<br />
<br />
<br />
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 />
KאLאאLא<br />
•<br />
•<br />
ELinear Delta Modulation: DMFא١ J٤ J٢<br />
אאאא א<br />
<br />
<br />
<br />
<br />
<br />
אJ٢ אW١٤ <br />
<br />
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 />
W<br />
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 />
•<br />
•<br />
•<br />
אאW<br />
אאאאא<br />
ESong algorithmFא J<br />
אא∆אאאאאא<br />
אאאKאא∆אא<br />
Kא<br />
<br />
E١<br />
E٢<br />
•<br />
- ٦٩ -
אא <br />
אא <br />
אא<br />
٢٣٧<br />
א <br />
א <br />
<br />
אJ٢ algorithmFאW١٩ ESong<br />
אאEdamped oscillationF<br />
<br />
<br />
ESpace shuttle algorithmFאאא J<br />
Kאאאאאאא<br />
אאאא،אKא،<br />
KאאאאKא<br />
<br />
<br />
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 />
٢٣٧<br />
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 />
<br />
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 />
<br />
(ASK,FSK,PSK)אאאאא<br />
KEFא<br />
<br />
W(Binary modulation)אא J١<br />
אאאאא(bit) <br />
Rb = Rs<br />
N<br />
M= 2<br />
N = logM = log 2<br />
2<br />
=1<br />
(1-3)<br />
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 />
Rs = Rb/2<br />
N 2<br />
M= 2 = 2 = 4<br />
N= log2 M = log 4 = 2<br />
(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 />
Rs = Rb/N = Rb/log2 M<br />
2<br />
N<br />
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 />
<br />
אאW<br />
אאאFאאאEASK)<br />
אאאאאא(1-3)(AM.DSBTC) <br />
+V 1 1 <br />
000 0 <br />
t <br />
-V <br />
<br />
אאאאE1-3F<br />
א(NRZ-L)א Vm(t)אאE١<br />
אא<br />
Vc (t)= Ac cos 2π fct<br />
W(ASK)אאאאאE٢<br />
V ASK(t)<br />
= [A±V m(t) ] cos 2π fct<br />
= [Ft±v] Cos 2π fct<br />
= A[1±V/A] Cos 2π fct<br />
= A[1±m] cost 2π fct<br />
(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 />
<br />
אEASKFE2-3F <br />
(Efficiency)<br />
(ASK)<br />
אא<br />
m = 1א<br />
E2A٠VFאאא<br />
<br />
(ASKF(ASK)<br />
אאאאאאא<br />
א(3-3) <br />
<br />
(ASK)E3-3F<br />
<br />
- ٧٤ -
אא <br />
אא<br />
אא<br />
٢٣٧<br />
א <br />
א <br />
EASKFEASKF<br />
(Envelope detector)א<br />
<br />
<br />
אאW<br />
אא(DSB-SC)אאאאא<br />
אאאOOK)) (ON-OFF KEYING)<br />
Wאאאא<br />
<br />
(modulating signal)EunipolarFאאאE١<br />
Vm (t) ={ +1 V logic 1<br />
or<br />
{ 0V logic 0<br />
אאאאאOOK E٢<br />
Vook(t) =Vm (t) *Vc (t)<br />
=Vm * Ac cos wct<br />
= { Ac*cos wct for logic (1)<br />
{٠ for logic (0)<br />
(5-3)<br />
(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 />
<br />
EOOKאFE5-3F<br />
<br />
- ٧٦ -
אא <br />
אא<br />
אא<br />
٢٣٧<br />
א <br />
א <br />
(OOK Detection)אא<br />
Wא<br />
(coherent detection)אאאE١<br />
(synchronous detection)אא<br />
א(reference carrier)אאא<br />
אאאאKאאאא<br />
אאאאאאא<br />
אאאאאא<br />
(phase & frequency mismatch distortion)<br />
אE6-3Fאאאאאאא <br />
(synchronous detection) بواسطة الكشف التزامني (AMDSB-SC)<br />
<br />
EOOKאאF(6-3)<br />
<br />
(Non Coherent Detection)אאאE٢<br />
(Asynchronous detection)אא<br />
אאאאאאאאא<br />
(7-3)(Envelope detector)<br />
<br />
<br />
EאאאאאאFE7-3F<br />
- ٧٧ -
אא <br />
אא<br />
אא<br />
٢٣٧<br />
א <br />
א <br />
Wא<br />
אEdiodeFאאאאאE١<br />
אאאאchargeF Etime constant of<br />
Eforward resistanceFאא<br />
אאאEreverse biasedFא<br />
אERFאאאא<br />
אאTZR*C<br />
א<br />
אאאאאאאאאE٢<br />
א<br />
binary FאאאאאאאE٣<br />
(comparator)אאאrestoration)<br />
<br />
EOOK BandwidthFEOOKFא<br />
EpcmFVm(t)אאאE١<br />
(ones followed by zeros)אא<br />
Tm = 2Tb א<br />
fm = 1/Tm =1/2Tb = Rb/2 <br />
<br />
)Vm(t)אא(Fc)אא(OOK)E٢<br />
אE <br />
אאאEFcFE8c-3F<br />
EFcFEFmFאאא<br />
<br />
- ٧٨ -
אא <br />
אא<br />
אא<br />
٢٣٧<br />
א <br />
א <br />
<br />
EOOKFאאאאE8-3F<br />
ERbFEdata rateFאEFmFאאE8c-3Fא<br />
Wא<br />
Rb=1/Tb =1/(Tm/2) =2Fm<br />
<br />
EFcFאאאאE٤<br />
אאאאא<br />
אאאאא(BandwidthF <br />
WE3-3Fא<br />
BT= Rb = 2Fm (6-3)<br />
W1-3<br />
(200 Kbit/sec)ENRZ-PCMF<br />
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 />
(PE)<br />
אאFאאאE٢<br />
אאאאאEאאא<br />
- ٨٠ -<br />
K<br />
Wאא(SER)(BER)אE٣<br />
(BASK,BFSK,BPSK)אא J<br />
(1 bit)א(symbol)<br />
KאאEאFא<br />
PB = PEBER = SERW<br />
(QASK,QFSK,QPSK)אא J<br />
PB = 1/2 PEBER = 1/2 SER(2 bit)<br />
(µASK,µFSK,µPSK)אא J<br />
אאא(N)א(N)<br />
אאW <br />
PB = PE / N = PE / log2M<br />
EאאאאFאאא:(M)<br />
אKKKKKKKPB = PE/ 4 WN= log2 16 = 4 M = 16 (16-PSK) <br />
אאאאאFא(BER)אאE٤<br />
K<br />
אאאאאFאFE٥<br />
W(Es / No)(SER)(Eb / No)<br />
K<br />
(BER)E٦<br />
א=Eb,Es<br />
(W/HZ)אאא=No
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 />
e −<br />
(8-3)<br />
EF(bit)אEb = (E1+Eo) / ٢ <br />
אא(9-3)א <br />
<br />
<br />
E1=C*Tb = A2 Tb/2<br />
Eo = 0<br />
(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 />
GOTEVOT appreciates the financial support provided by BAE SYSTEMS
Change language