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AM, FM, and Digital Modulated Systems Chap. 5
m(t)
T b
+1
1
t
Data
to
y x y x y x y x y
Data
on x(t)
Data
on y(t)
T b
2T b
2T b
3T b 4T b 5T b 6T b 7T b 8T b 9T b
t
t
A c
x(t)
t
A c
A c
y(t)
t
A c
Figure 5–34
MSK quadrature component waveforms (Type II MSK).
always a positive half-cosinusoid. For Type I MSK, the pulse shape [for both x(t) and
y(t)] alternates between a positive and a negative half-cosinusoid. For both Type I and
Type II MSK, it can be shown that there is no one-to-one relationship between the input
data m(t) and the resulting mark and space frequencies, f 1 and f 2 , respectively, in the