RF Communication and Signals Experiments
And the carrier signal is
u
c
(
t
) =
U
cm
cos
ω
c
t
=
U
cm
cos2
π
f
c
t
An FM signal varying to changes in the modulating signal is shown
in Figure 6-1.
Figure 6-1.
An FM signal
varying to the
change of a
modulating
signal
t
t
t
u
Ω
c
u
u
In the positive half-period of the modulating signal, the
frequency of the modulated signal is higher than the frequency of
the carrier signal. At the peak of the positive half-period, the
angular frequency of the modulated signal is at its peak.
In the negative half-period of the modulating signal, the
frequency of the modulated signal is lower than the frequency of
the carrier signal, and its angular frequency is at its lowest. The
angular frequency
ω
of an FM wave changes in response to changes
in the modulation signal.
Then
ω
=
ω
c
+
Δω
cos
Ω
t
In this formula,
ω
c
is the angular frequency of the carrier wave,
Δω
69
Содержание GRF-1300
Страница 15: ...Introduction to the GRF 1300 Figure A 10 Operation interface for HyperTerminal 13 ...
Страница 19: ...Overview of the Time and Frequency Domain Time domain Frequency domain 17 ...
Страница 20: ...GRF 1300 User Manual and Teaching Materials NOTES 18 ...
Страница 21: ...Overview of the Time and Frequency Domain NOTES 19 ...
Страница 22: ...GRF 1300 User Manual and Teaching Materials NOTES 20 ...
Страница 23: ...Overview of the Time and Frequency Domain NOTES 21 ...
Страница 24: ...GRF 1300 User Manual and Teaching Materials 22 NOTES ...
Страница 30: ...GRF 1300 User Manual and Teaching Materials NOTES 28 ...
Страница 31: ...An Introduction to Spectrum Analyzers NOTES 29 ...
Страница 56: ...GRF 1300 User Manual and Teaching Materials NOTES 54 ...
Страница 57: ...RF Communication and Signals Experiments NOTES 55 ...
Страница 58: ...GRF 1300 User Manual and Teaching Materials NOTES 56 ...
Страница 59: ...RF Communication and Signals Experiments NOTES 57 ...
Страница 95: ...RF Communication and Signals Experiments 10MHz frequency deviation test results 93 ...
Страница 101: ...Test for Learning Outcomes NOTES 99 ...
Страница 102: ...GRF 1300 User Manual and Teaching Materials NOTES 100 ...
Страница 103: ...Test for Learning Outcomes NOTES 101 ...
Страница 104: ...GRF 1300 User Manual and Teaching Materials 102 NOTES ...
Страница 109: ...Appendix Modulation Index and Sideband Amplitude Comparison Table 107 ...