Tektronix RSA6100A Series, Help Manual

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Analog Modulation > FM Parameters Tab
Parameters Tab
The Parameters tab enables you to specify parameters for carrier detection.
Setting Description
Burst detect threshold This parameter speci fi es the power level used to determine whether a burst is present.
A valid burst is required to take measurements. The burst detected fi rst is used for
the analysis. The units for burst detect threshold are dBc, relative to the maximum
acquisition sample data points level.
Measurement BW
Speci fi es the bandwidth about the center frequency at which measurements are made.
Frequency offset Displays the carrier signal’s offset from the instrument’s measurement frequency. Auto is
used to select the method for determining the carrier frequency. When Auto is selected,
the instrument determines the carrier frequency by analyzing the signal. When Auto is
deselected, you can set the carrier frequency offset using Frequency Offset.
Load from Marker Pressing this button sets the frequency offset to the frequency offset of the selected
marker. (Pressing this button automatically deselects Auto.)
xxx
Frequency Offset
In Auto (Auto is selected), the instrument scans the measurement bandwidth about the measurement
frequency and looks for the highest-powered signal. This is de
fi ned as the carrier frequency. In Manual
(Auto is deselected), the carrier frequency is speci fi ed by adding/subtracting the speci fi ed Frequency offset
from the measurement frequency. Range: -(Measurement BW*1.1)/2 to +(Measurement BW*1.1)/2. If
the
Load Δ from marker button is pressed, the frequency offset is determined from the phase difference
between the two markers on screen compared to the time between the two markers. This function is useful
for removing frequency slope from the phase modulated signal.
Load from Marker
When the Auto check box is selected, the instrument scans the measurement bandwidth about the center
frequency and looks for the highest-powered signal. This is de
fi ned as the carrier frequency. When
the Auto check box is deselected, the carrier frequency is speci fi ed by adding/subtracting the speci fi ed
Frequency offset from the center frequency. Pressing the Load from marker button loads the marker
frequency into the Frequency offset box.
RSA6100A Series Real-Time Spectrum Analyzers Help
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