R&S 1129.7246.03, Operating Manual

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R&S ESU Instrument Functions
IF Spectrum Analysis Mode
4.92 Operating Manual 1302.6163.12 - 03
In this menu, the mode of representing the measured data in the frequency or time
domain in the 625 pixels of the display is determined. Upon start of the measure-
ment, each trace can be displayed either completely new or based on the previous
results.
Traces can be displayed, blanked and copied.
The default setting is trace 1 in the overwrite mode (CLEAR/WRITE mode), trace 2
and trace 3 are switched off (BLANK mode).
The CLEAR/WRITE, MAX HOLD, MIN HOLD, AVERAGE, VIEW and BLANK soft-
keys are mutually exclusive selection keys.
SELECT
TRACE
The SELECT TRACE softkey activates the entry for the active trace (1, 2, 3).
Remote command:
--
(selected via numeric suffix of TRACe)
CLEAR/WRITE
The CLEAR/WRITE softkey activates the overwrite mode for the collected mea-
sured values, i.e. the trace is overwritten by each sweep.
For further information refer to the descriptions in section “Receiver Mode” –
“CLEAR/ WRITE” on page 4.72 .
MAX HOLD The MAX HOLD softkey activates the max peak detector.
For further information refer to the descriptions in section “Receiver Mode” – “MAX
HOLD” on page 4.72 .
AVERAGE
The AVERAGE softkey activates the trace averaging function. The average is
formed over several sweeps.
Depending on the setting of AVG MODE LOG / LIN, the logarithmic level values or
the measured power/voltage values are averaged.
Remote command:
DISP:WIND:TRAC:MODE AVER
Description of averaging
Averaging is carried out over the pixels derived from the measurement samples.
Several measured values may be combined in a pixel. This means that with linear
level display the average is formed over linear amplitude values and with logarithmic
level display over levels. For this reason the trace must be measured again when
changing between
LIN and LOG display mode. The settings CONT/SINGLE
SWEEP and running averaging apply to the average display analogously.
A running average is calculated according to the following formula:
Due to the weighting between the new measured value and the trace average, past
values have practically no influence on the displayed trace after about ten sweeps.
With this setting, signal noise is effectively reduced without need for restarting the
averaging process after a change of the signal.