Rohde & Schwarz HMS-X, Руководство пользователя

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Instrument Functions
The submenu SET TO offers addition marker functions.
Marker to center (MKR TO CENT) allows to set the activa-
ted marker to the center frequency. In contrast to marker
to center allows center to marker (CENT TO MKR) to set
the center frequency to an activated marker. A noise mar-
ker displays the noise at the marker position. The REF TO
MKR softkey allows to set the reference level to the value
of the current marker. This makes it easy to optimize the
R&S®HMS-X level display range if the levels being investi-
gated are low. The Noise function is used to calculate the
noise power density at the marker position.The spectrum
analyzer calculates the noise power density in dBm/Hz
from the trace pixel values, the selected resolution band-
width and the detector. Noise power density can provide
useful information when measurements are made on noise
or digitally modulated signals. Valid results are only obtai-
ned, if the spectrum in the vicinity of the marker has a flat
frequency response. The function gives incorrect results if
measurements are made on discrete signals. Noise mar-
ker mode is designated by a leading “N” in the marker rea-
dout. The noise marker can be switched on/off by pressing
the softkey. The softkey ALL OFF can be used to turn off
all previous activated markers simultaneously.
6.9 Peak-Search
The PEAK SEARCH key activates a menu which is used to
detect peaks in the trace and assign markers to them:
❙ PEAK : this function places the marker or the delta marker
on the highest peak of the trace. The function acts on the
active marker which is activated in the marker menu.
❙ NEXT PEAK : this function places the marker or the delta
marker relative to their current positions on the next lower
peak of the trace. The function acts on the active marker
which is activated in the marker menu.
❙ NEXT LEFT : this function places the marker or the delta
marker relative to their current positions on the next left
peak of the trace. The function acts on the active marker
which is activated in the marker menu.
❙ NEXT RIGHT : this function places the marker or the delta
marker relative to their current positions on the next right
peak of the trace. The function acts on the active marker
which is activated in the marker menu before.
❙ MINIMUM : this function places the marker or the delta
marker on the lowest value of the trace. The function acts
on the active marker which is activated in the marker
menu.
❙ ALL TO PEAK : This function will set all markers to the
highest peak. From this point a new arrangement can be
realized easily.
6.10 Limit Lines
Limit lines are used to set limits for level characteristics
versus time or versus frequency on the display. They must
not be exceeded. For instance, the upper limits of permis-
sible spurious or harmonics of a DUT are marked by limit
lines. In the R&S®HMS-X the upper and lower limit value
can be preset by way of limit lines. Pushing the key LINES
will open the setting menu to set limit lines. The softkey
UPPER LIMIT activates / deactivates the upper limit line
which is displayed as a red line. After activating the soft-
key UPPER POS the amplitude value for the upper limit line
can be set via the knob. The softkey LOWER LIMIT activa-
tes / deactivates the lower limit line which is displayed as a
red line. After activating the softkey LOWER POS the amp-
litude value for the lower limit line can be set via the knob.
Additionally, the softkey BEEP activates an acoustic sig-
nal which warns as soon as the trace leaves the amplitude
range defined by the upper and lower limit line. The soft-
key MESSAGE activates a message in the upper left cor-
ner of the trace display which shows if the whole trace is
inside (pass/green) or outside (fail/red) the amplitude range
defined by the upper and lower limit line.
6.11 Measure Menu
The key MEAS opens the measure menu with different op-
tions. The softkey CF

RX opens the receiver mode tu-
ned to the actual center frequency. The softkey M1

RX
opens the receiver mode tuned to the actual frequency of
marker M1. The softkey REFLECTION CAL starts the calib-
ration wizard of the reflection measurement. To use the wi-
zard the HAMEG VSWR bridge HZ547 can be used. The
VSWR bridge HZ547 allows the measurement of the vol-
tage standing wave ratio (VSWR) and the reflection coef-
ficient of 50 Ω devices. The frequency range of the HZ547
is 100 kHz to 3 GHz.
The R&S®HMS-X with activated TG option (R&S®HMS-TG
/ R&S®HV211) guides the user through all steps of the re-
flection measurement sequentially. Concerning the reflec-
tion measurement you have to connect the VSWR measu-
ring bridge to the spectrum analyzer. The tracking genera-
tor (TG) will be switched on automatically, if you don‘t have
activated it already.
The signal source (tracking generator / OUTPUT) needs
to be connected to the IN connector of the VSWR bridge.
Staged limit lines are not possible with the R&S®HMS-X directly.
In this case the EMC software resp. the EMC option (R&S®HMS-
EMC / R&S®HV213) is needed to create limit lines as CSV file.
Fig. 6.14: Calibration menu of the VSWR wizard
The wizard for the reflection measurement is only available with
the TG option R&S®HMS-TG resp. R&S®HV211 voucher.