Tektronix RSA6100A Series, Руководство пользователя

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Analog Modulation > PM Trace Tab
Setting Description
Burst detect threshold 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 frequency 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 Δ from Marker Pressing this button disables the Auto Frequency Offset function and sets the Frequency
offset to the frequency offset calculated from the difference between MR (the marker
reference) and the selected marker (or M1 if MR is currently the selected marker).
Phase offset Displays the phase offset. When Auto is selected, the instrument determines the phase
offset. When Auto is deselected, the user sets the phase offset with this control.
Load from marker Pressing this button sets the phase offset to the phase 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.
Phase Offset
In Auto (Auto is selected), the instrument sets the phase offset to fi t the waveform to the screen centering
0° phase on the vertical axis. The actual phase offset is indicated on the Phase Offset readout. In Manual
(Auto is deselected), the instrument sets the phase offset using the value speci
fi ed in Phase offset. For
example, when Phase offset is set to 10°, the waveform shifts upward by 10° on screen. Selecting Load
from marker sets the phase offset to the value of the selected marker. Range: –180 to +180°.
Trace Tab
The Traces Tab allows you to set the display characteristics of displayed trace.
RSA6100A Series Real-Time Spectrum Analyzers Help
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