COMMUNICATIONmSYSTEMS:mANmINTRODUCTIONmTOmSIGNALSmANDmNOISEmINmELECTRICALmCOMMUNICA
TION,mFOURTHmEDITION
A.mBRUCEmCARLSON,mPAULmB.mCRILLY,mANDmJANETmC.mRUTLEDGE
PublishedmbymMcGraw-HillmHighermEducation,manmimprintmofmThemMcGraw-
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Themcontents,mormpartsmthereof,mmaymbemreproducedminmprintmformmsolelymformclassroommusemwithm COMMUNICATIONmSYS
TEMS:mANmINTRODUCTIONmTOmSIGNALSmANDmNOISEmINmELEmCTRICALmCOMMUNICATION,mprovidedmsuchmreproduc
tionsmbearmcopyrightmnotice,mbutmmaymnotmbemreproducedminmanymothermformmormformanymothermpurposemwithoutmthempriormw
rittenmconsentmofmThemMcGraw-
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,Chapterm2
2.1-1
Aejϕ
Aemj nmm
cnm
Tm/
emj2πjϕm(mmnm)fm tmdtm
0
m2m
0 ϕ
Aem sinc(mmn)m
T0
T0m /
0 otherwise
2m
2.1-2
2m Tm0m0
c0m v(t) /m4m m2πnt T0m/2 m 2πntm 2Am πn
cm Acosm dtmm (A)cosm dtm sinm
Tm T T πn 2
n
0
T
mm
/m4m
0
0 0 0
n 0 1 2 3 4 5 6 7
cn 0 2mAm/mπ 0 2mAm/m3π 0 2mAm/m5π 0 2mAm/m7π
argmcn 0 180 0 180
2.1-3
2
cm T m/2m 2mAtm 2πnt A A
0
n
Tm 0 A m cos m dtm sinπn m 2m (cosπmnm1)
T T πn
0 0m 0 (πmn)
n 0 1 2 3 4 5 6
cn 0.5A 0.2A 0 0.02A 0 0.01A 0
argmcn 0 0 0 0
2.1-4
2-1
, 2 T0m/2 m
cm Acosm
2πmtm (cont.)
0
Tm
0
0 T
0 0
2-2
, 2/2 mm m Tm 2mAmsinmπmπmn2t
2πt 2πnt sinmπmπmn2tm/ T m/2m 0
cnm 0 Acos cos m/mT mT
dtm 0m
0m
T T T T 4(π
mπmn)m/mT0
4(πmπn)/mT0 0
0 0m m
Am A / 2mn 1
sinc(1mn)msinc(1mn)m
0 0 0m m m
m
2 0 otherwise
2.1-5
2 T0m/2m 2πnt Am
cm jm Asinm dtmjm (1cosπmn)
Tm
n
0 T πn
0 0
n 1 2 3 4 5
cn 2mAm/mπ 0 2mAm/m3π 2mAm/m5π
argmcn 90 90 90
2.1-6
2mAmsinmπmπmn2t
mm/mT0sinmπmπmn
T0m /2m
2 2πtm m2πntm
T0m/2m 2tm/mTm
cnm j dtmjm m
Tm
m m m
Asin sinm 4(πmπmn)/mT
4(πmπmn)/
m m 0
0 T T T
mT
0 0 0
0 0 0
0m
mAm mmjAm/m2 nm1
jm sinc(1nm)msinc(1n)m
2 m 0 otherwise
2.1-71
cm 2mT0m / jnω0mt
T0
jnω0t
n 0 v(t)me dtmTm0 /m2m v(t)e dtm
T0m
T0
v(t)ejnω0mtmdtm T m/2 v(λmTm/2)mejnω0λmejnω0/mT20m
m dλ
0
where
T
m m /0m2
0
0
T0m /m2m
emjnπm v(tm)ejnω0mtmdt
0
sincem emjnπm1m formevenmn,m cm 0m formevenmn
n
2-3