Errata for
Communications Engineering: Essentials for Computer Scientists and Electrical
Engineers
By R.C.T. Lee, Mao-Ching Chiu, and Jung-Shan Lin
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P. 1 Line 15, change “contituent” to “constituent”.
P.2, Lines 6 and 7, change “analogue” to “analog”.
P.2, Line 29, Change “method” to “multiplexing”.
P.2, Line 33, change “ODFM” to “OFDM”.
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P. 7, Line 7, change “where the vi” to “where the vi” (change to boldface)
P. 9, Equation (2-16)
Change “ T  1 / Sc ” to “ T  1/ fc ”.
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P.12, Fig. 2-2(d), change “  1 (t )2 (t )dt ” to “  1 ( )2 ( )d ”.
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P. 13, Fig. 2-3(d), change “  1 (t )2 (t )dt ” to “  1 ( )2 ( )d ”.
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P. 13, Line 6 from the bottom to the following equation: A  B  ... ,
Change the paragraph to the following:
Let An  (1 (t1 ), 1 (t2 ),,1 (tn )) and Bn  (2 (t1 ), 2 (t2 ),,2 (tn )) .
Let  
t
0
0
t
t
0
0
We have:
(b  a)
An  Bn , as n  
a
n
i 1
P. 14, Fig. 2-4 (a), change “ 1 (1) ” to “ 1 (1)  1 ”

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(b  a )
.
n
t
b
n
1 (t ) 2(t )dt    (1ti ) (t2i ) 
1
t
0
0
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P. 14, Fig. 2-4 (b), change “  1 (t )2 (t )dt ” to “  1 ( )2 ( )d ”
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P. 16, Second line from the bottom, change “ 1 (t ) cos(2 t ) ” and
“ 2 (t ) cos(6 t ) ” to “ 1 (t )  cos(2 t ) ” and “ 2 (t )  cos(6 t ) ”, respectively.
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P.17, Second line from the bottom, change “discrete the” to “the discrete”.
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P.21, Line 8, change “periodic frequency” to “fundamental frequency”.
P. 30, Fig. 3-9, add “ x(t ) ” on the x-axis.
P. 31. Fig. 3-10, add “ x(t ) ” on the x-axis.
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P. 36, Equation (3-45), change “ bk 
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P. 37, Equation 3-48
Change
1
(
k
” to
“ bk 
1
(
k
”
1
Communications Engineering: Essentials for Computer Scientists and Electrical Engineers, R.C.T. Lee,
Mao-Ching Chiu, Jung-Shan Lin © 2007 John Wiley & Sons (Asia) Pte Ltd
“ f 3 (t ) 
1  2
k
k
k
k
  sin(
)(cos( ) cos( 2kfc t )  sin(
) sin(
) sin( 2kfc t )) ”
2 k 1 k
2
4
2
4
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1  2
k
k
k
  sin(
)(cos( ) cos( 2kfct )  sin(
) sin( 2kfct )) ”.
2 k 1 k
2
4
4
P. 40, Equation (3-62): Change “ cos 2( kf 0t ) ” to “ cos(2 kf0t ) ”, “ sin(2 kf 0 )t ”
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to “ sin(2 kf 0t ) ”
P.45, Line 3, change “ xk ”
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P. 45, Line 11 from the bottom, delete
to “ f 3 (t ) 
to “ X k ”.
1
( 1 c osk( ) j) ( 2 ) s ki0 fn (t 2
j 2 k
1

( 1 c osk( ) ) 
s ikfn0t( 2
)
k

)
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P48, Equation (3-84), change “ x0 ” to “ X 0 ”.
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P.48, Line 5 from the bottom, change t0  
t0  
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T
2
to t0  
T
2
to t0  
T
and change
2
T
.
2
P. 48 Equation (3-85), change
“ x (t )  x(t ) with 
T
T
 kT  t   kT ”
2
2
to
“ x (t )  x(t  kT ) with 
T
T
 kT  t   kT ”
2
2
T
T
to
2
2
P. 51, Equation (3-98), change x( f ) to X ( f ) .
P. 52 Fig. 3-17(b), change 2 T to 2 Ts .
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P. 49, Figure 3-16(b), change 
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P. 52, Line 2, change “ 0  T   ” to “ 0  Ts   ”.
T
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P. 52, Equation (3-100), change “ 
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P. 55, Line 10 (above Equation (3-108)), change “(3.75) “ to “(3-73)”.
P. 55, Line 18 (after Equation (3-108)), change “(3-107)” to “(3-108)”
P. 58, Equation (3-119), change x(t ) y (t ) to x (t )  y (t ) .
P. 59, Line 1, change x(t ) y (t )  y (t ) x(t ) to x (t )  y (t )  y (t )  x (t ) .
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P. 59, Line 5 e  j 2 should be e  j 2 f  . Line 6 Same as above.
P. 59, the last Equation should be as follows:
T
” to “ 
Ts
 Ts
”.
2
Communications Engineering: Essentials for Computer Scientists and Electrical Engineers, R.C.T. Lee,
Mao-Ching Chiu, Jung-Shan Lin © 2007 John Wiley & Sons (Asia) Pte Ltd
z (t )  






X ( )Y ( f  )d e j 2 ft df
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P. 61, Fig. 3-20(d), change the “1” in x-axis on the left to “-1”.
P. 63, Fig. 3-21 (a), delete “ x(t  u ) ” in y-axis
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P. 63, Fig. 3-21 (c), add “ t  1 ” to the rightmost point on the square wave
P. 65, For both Case 1 and Case 2, change “ T ” to “ Ts ”.
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P. 66, Figure 3-23(b) and Figure 3-24(b):
Change “ x( f ) ” to “ X ( f ) ”.
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P. 68, the first line after Eq (3-145), change (3-57) to (3-58) and (3-141) to
(3-142).
P. 70, Equation (3-149), change “ i  i ' ” to “ i ' i ”
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P. 73, Line 13, change “ n  3 ” to “ n  4 ”.
P. 74, Line 12, change “ n  3 ” to “ n  4 ”.
P. 75, Step 2, change “ Bn /2 ” to “ Bn /21 ” and “ Cn /2 ” to “ Cn /21 ”
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P. 78, Example 3-21, change “Example 3-18” to “Example 3-19”
P. 78, Line 2 of Example 3-21, change “ C0  3 ” to “ C0  4 ”
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P. 78, Example 3-22, change “Example 3-19” to “Example 3-20”
P. 79, line 10:
Change “Equation (3-62)” to “Equation(3-148)”.
P. 79, Equation (3-174)
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Change “ an( n 1) i ” to “ an 1wn( n 1) i ”, “ an( n1)( ni ) ” to “ an1wn( n1)( ni ) ” and “ an( n1)i ” to
“ an1wn( n1)i ”
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P. 79, Line 7 from the bottom, change “(3.6-1)” to “(3-167)”.
P. 80, Line 7, change “for” to “for”.
P. 80, Line 7, change “n-1” to “ n  1 ”.
P. 80, Line 14, change “the Fourier …” to “the discrete Fourier …”.
P. 80, Line 2 from the bottom, add “.” after “ x(( n  1)Ts ) ”.
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P. 81, Line 3, change “the” to “the”.
P. 81, line 14:
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Change ”Example 3-18” to ”Example 3-19”
P. 85, Last Line: change “frequency shift” to “phase shift”.
P. 86, Line 5, change “3-23” to “3-24”.
P. 86, Fig. 3-37, change the figure used in Fig. 3-27 to the one used in Fig. 3-3
(P.19).
P. 86, Line 8, change “3-18” to “3-19”.
P. 86, Line 7 from the bottom, change “inverse Fourier” to “inverse discrete
Fourier”.
3
Communications Engineering: Essentials for Computer Scientists and Electrical Engineers, R.C.T. Lee,
Mao-Ching Chiu, Jung-Shan Lin © 2007 John Wiley & Sons (Asia) Pte Ltd
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P. 87, Line 3 from the bottom, delete “a discrete Fourier thow”.
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P. 89, caption of Fig. 3-31, change “Figure 3-29” to Figure 3-30”
P. 89, Line 3 of Last Para.: change “less than” to “not greater than”.
P. 89, Line 3 from the bottom, delete “Furthermore, the time … has to be 2mf.”
P. 94, Problem 3.11, change all functions “ x(u ) ” and “ y (u ) ” to “ x(t ) ” and
“ y (t ) ”.
P. 94, Line 4 from the bottom, change “ a(i ) ” to “ ai ”
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Chapter 4, change the word “Analogue” to “Analog” in the heading of all
odd-numbered pages of Chapter 4.
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P. 99, Line 6, change “ volt 1 ” to “ volt 1 ”.
P. 100, Line 11 from the bottom, change “then” to “than”.
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P. 100, Line 6 from the bottom, change “then” to “than”.
P. 102, Lines 3 and 5, change “then” to “than”.
P. 103, Line 16, change “ in Section 3.4” to “in Section 3.6”.
P. 104, Fig. 4-6 (b), the x-axis should be labeled “ f ”
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P. 104, Line 6 from the bottom, change “3.3” to “3.6”.
P. 105, Fig. 4-7 (b)-(d), all of the x-axis should be labeled “ f ”
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P. 110, line 20:
Change ” S ' ( f ) 
Ac
A
M ( f )  c [ M (2 f  f c )  M (2 f c  f )] ”
2
4
Ac
A
M ( f )  c [ M ( f  2 f c )  M ( f  2 f c )] ”
2
4
P. 111, Line 1, change “ M ( f c  f ) ” to “ M ( f  f c ) ”.
to ” S ' ( f ) 
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P. 111, Line 2, change “ M ( f c  f ) ” to “ M ( f  f c ) ”.
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P. 114, Line 2, change “  / 2 ” to “  / 2 ”.
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P. 125, Line 8, change “  Ac 2f c m(t ) ” to “  Ac 2k f m(t ) ”.
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P.125, Fig. 4-22(b), change “ f e ” to “ f c ”.
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P. 126, Fig. 4-23(a) C1 and C2 should belong to the band-pass filter, not the
demodulator. The correct figure is shown below:
4
Communications Engineering: Essentials for Computer Scientists and Electrical Engineers, R.C.T. Lee,
Mao-Ching Chiu, Jung-Shan Lin © 2007 John Wiley & Sons (Asia) Pte Ltd
R
L1
C1
m(t )
u (t )
L2
C2
R
Bandpass filter
Envelope detector
Amplitude Response
Amplitude Response
(a)
f1
f1
f2
f2
f
f
(b)
Linear region
(b)
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P. 128, Para 3, Line 1, delete the second “is”.
P. 129, line 13: change “It can be seen that the undesired signal will also …”
to ”: It can be seen that the first term of above equation, representing the
undesired signal, will also…”
P. 139, line 3 from the bottom, change “(3-102)” to “(3-103)”.
P. 139, Equation 5-8:
2
2

 
ST (t ) 
ST ( f ) 


Change “  lim
df ” to “  lim
df ”
   T 
   T 


T
T





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P. 149, line 2 from the bottom, change “(3-102)” to “(3-103)”
P. 157, Figure 5-17, change “ 90 ” to “- 90 ”
P. 158, Table 5-1:
Change “ E / 2 ” to “ E 2 ”
5
Communications Engineering: Essentials for Computer Scientists and Electrical Engineers, R.C.T. Lee,
Mao-Ching Chiu, Jung-Shan Lin © 2007 John Wiley & Sons (Asia) Pte Ltd
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P. 158, line 12:
Change “ a2  E 2 ” to “ a2   E 2 ”.
R
L1
C1
m(t )
u (t )
L2
C2
R
Bandpass filter
Envelope detector
Amplitude Response
Amplitude Response
(a)
f1
f1
f2
f2
f
(b)
Linear region
(b)
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P. 160, Figure 5-19, change “ 90 ” to “- 90 ”
P. 161, Last line, change “1001101” to “10011011”
P. 164, Figure 5-22, replace the figure by the one which is shown below.
6
Communications Engineering: Essentials for Computer Scientists and Electrical Engineers, R.C.T. Lee,
Mao-Ching Chiu, Jung-Shan Lin © 2007 John Wiley & Sons (Asia) Pte Ltd
f
2
s6
s5
s7
E
s4
s8
1
s1
s3
s2
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P. 180, Line 25, change “signal” to “single”
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P. 180, Line 28, change “are N subchannels” to “are N subchannels as
indicated by Equation (5-92)”
P. 185, Line 4, change “ k f ” to “ K f ”
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P. 185, Line 8, change “Band 1” to “Band I”.
P. 197, Caption of Figure 6-8, change the “spectra” to “spectrum”
P. 211, line 2, change “spectrals” to “spectrum”
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P. 217, Figure 7-6 (b), change “ f1 ” to “ f j ” , change “  ( f  f ) ” to “  ( f  f j ) ”,
and change “  ( f  f ) ” to “  ( f  f j ) ”
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P. 231, Line 2 from the bottom, change “- - -” to “- - . -”
P. 236, Line 2 from the bottom, change “Table 8-1” to “Figure 8-1”
P. 238, Line 2, change “then” to “than”
P. 238, Equation (8-4), change “x” to “x”.
P. 248, Line 12, change “characteristics” to “characteristic”
7
Communications Engineering: Essentials for Computer Scientists and Electrical Engineers, R.C.T. Lee,
Mao-Ching Chiu, Jung-Shan Lin © 2007 John Wiley & Sons (Asia) Pte Ltd