Rohde & Schwarz FSV3000, Руководство пользователя

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Measurements and results
R&S
®
FSVA3000/ R&S
®
FSV3000
333 User Manual 1178.8520.02 ─ 08
5.13.3.5 Using transducer factors
The R&S FSV/A EMI measurement provides functionality to include transducer factors
in the test setup. Transducers are devices like antennas, probes or current probes that
are connected to the R&S
FSV/A to measure interferences or wanted signals. The
transducer converts the measured value such as field strength, current or RFI voltage
into a voltage across 50
Ω
. During the measurement, the transducer is considered a
part of the instrument.
A transducer usually has a frequency-dependent transducer factor that includes the
frequency response of the corresponding device. During level measurement, the trans-
ducer factor automatically converts the results into the correct unit and magnitude. A
transducer factor consists of a maximum of 1001 reference values. Each reference
value includes frequency, unit and level.
The R&S FSV/A EMI measurement adds several predefined transducer factors. In
addition, you can also create new and edit existing transducer factors.
For more information, see Chapter 10.5.1, "Basics on transducer factors" ,
on page 712 .
5.13.3.6 Initial measurement - peak search
The purpose of an initial peak search is to find signals with a high interference level
quickly. The peak search is performed with a fast detector like the peak or average
detector. The initial peak search is the basis for a possible refined measurement of
interferences with the detectors specific to EMI measurements.
The results of the initial peak search are shown in the Marker Table (see Chap-
ter 5.13.2, "EMI measurement results" , on page 325).
Peak searches can be performed automatically or manually.
Automatic peak search
If enabled, the automatic peak search starts as soon as you select the EMI measure-
ment and one or more markers are active. During automatic peak search, the
R&S
FSV/A looks for the strongest peaks in the frequency range you are measuring
and positions a marker on those peaks after each sweep. If a limit line is assigned to
the trace, the peak search is based on the level difference between the trace and the
limit line. For each active marker, a peak is searched. You can use up to 16 markers
simultaneously.
The largest peak is always assigned to the active marker with the lowest number; sub-
sequent peaks are assigned to the active markers in ascending order.
The R&S FSV/A allows you to distribute markers among several traces. If you do so,
the marker with the lowest number assigned to a particular trace is positioned on the
largest peak of the corresponding trace.
Electromagnetic interference (EMI) measurement