Tektronix RSA2200A, User Manual

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Modulation Analysis (Demod Mode)
RSA2203A & RSA2208A User Manual
3- 37
Demodulates and measures an FM signal. Figure 3--34 shows an example. The
main view displays the measurement results and the frequency deviation versus
time graph. MEASURE
→
Show Measurements is selected in Figure 3--34.
Meas Setup Menu.
The Meas Setup menu for the FM demod measurement
contains the following controls:
Auto Carrier. Determines whether to detect the carrier automatically.
H
On. Default . Automatically detects the carrier for every frame.
The error from the center frequency is shown on the Freq Error side key.
H
Off. Sets the carrier frequency using Frequency Offset described below.
Frequency Offset. Sets the carrier frequency when Off is selected in
Auto Carrier. Enter the carrier offset from the center frequency.
Range: --30 to +30 MHz
Threshold.
Sets the threshold level above which the input signal is determined
to be a burst in time domain. The burst detected first is used for the analysis.
Range: --100.0 to 0.0 dB
Main view
Measurement results
From the top:
G
Peak-to-peak frequency deviation
G
(Peak-to-peak frequency deviation) / 2
G
Positive peak frequency deviation
G
Negative peak frequency deviation
G
RMS frequency deviation
Overview: Power versus Time Subview: Spectrum
Frequency deviation variation
Figure 3- 34: FM demod measurement
FM Demod Measurement