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Modulation Analysis
R&S
®
Spectrum Rider FPH
237
User Manual 1321.1011.02 ─ 11
1 =
2 = AM or FM modulation
3 =
4 =
5 = "PASS" or "FAIL" result of the limit test
6 =
7 =
8 =
9 =
10 =
11 =
menu of analog modulation measurement. See
Chapter 10.1.3.1, "Analog Modulation"
The following analog modulation parameters are calculated:
Table 10-1: Analog Modulation Parameters
Label
Description
Carrier Power
Shows the power of the carrier without modulation
in dBm.
Carrier Freq Offset
Shows the deviation of the calculated carrier fre-
quency to the ideal carrier frequency in Hz.
Mod Index (AM domain)
Shows the difference in amplitude the carrier sig-
nal is modulated with.
Freq Deviation (FM domain)
Shows the frequency deviation that the carrier
signal is modulated with.
Modulation Rate
Shows the modulation rate in %.
Modulation rate = (Frequency Deviation /
Refrence Deviation ) * 100 %
+Peak
-Peak
Shows the minimum and maximum frequency
deviation (FM signals) or modulation depth (AM
signals).
±
Peak/2
Shows the average frequency deviation (FM sig-
nals) or modulation depth (AM signals). (| +Peak |
+ | -Peak |) / 2
RMS
Shows the root mean square of the frequency
deviation (FM signals) or modulation depth (AM
signals).
Mod Freq
Shows the modulation frequency.
SINAD
Signal-to-noise and distortion
Measures the ratio of the total power to the power
of noise and harmonic distortions. The noise and
harmonic power is calculated inside the AF spec-
trum span. The DC offset is removed before the
calculation.
Analog Demodulation
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