Tektronix NetTek YBT250, Руководство пользователя

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Locating Interference
3- 38
YBT250 Field Transmitter & Interference Tester User Manual
Identifying a Signal
Requires Option IN1
Once you can see a signal that you think may be interfering, you can
use the automated identification function to identify the signal. The
YBT250 will make an estimate of the signal type, choosing between
GSM, cdmaOne/cdma2000/1xEV-DO, W-CDMA, IS-136, and
analog FM signal types.
1. In the Interference display (button 3), tap the Identify tab if
needed.
2.
Look at the spectrum display to locate the suspected interfering
signal. Tap the trace at the frequency of the interfering signal to
set the measurement frequency. Try to set the Measurement
Frequency to the center of the signal.
3.
Look at the
Assignments for this Freq.
readout at the lower left
of the display. See Figure 3--20.
This readout displays the signal standard (more than one might
be displayed) that has channels defined at the measurement
frequency. The YBT250 first looks at the list of preferred signals
and then looks at the global channel reference to check for a
match. If the Measurement Frequency does not match with a
supported standard,
Not Found is displayed.
4. Select Measure to invoke the Identify function.
The YBT250 will perform a series of measurements to identify
which signal standard the signal’s characteristics most closely
match. The results of the Identify function are displayed in the
Measurements suggest results box. The signals are sorted by
frequency, with the signal that most closely matches the
measurement frequency listed first. See Figure 3--21.