Rohde & Schwarz VSE-K149, User Manual

Page: 23 / 143

Configuration
R&S
®
VSE-K149
23 User Manual 1179.3315.02 ─ 01
To avoid the LO feedthrough the spectrum analyzer provides an alternative signal path
to the A/D converter, referred to as the
direct path . By default, the direct path is
selected automatically for RF frequencies close to zero. However, this behavior can be
disabled. If "Direct Path" is set to "Off" , the spectrum analyzer always uses the analog
mixer path.
"Auto" (Default) The direct path is used automatically for frequencies close
to zero.
"Off" The analog mixer path is always used.
Remote command:
INPut<ip>:DPATh
on page 86
High Pass Filter 1 to 3 GHz
Activates an additional internal high-pass filter for RF input signals from 1 GHz to
3 GHz. This filter is used to remove the harmonics of the analyzer to measure the har-
monics for a DUT, for example.
This function may require an additional hardware option on the connected instrument.
(Note: for RF input signals outside the specified range, the high-pass filter has no
effect. For signals with a frequency of approximately 4
GHz upwards, the harmonics
are suppressed sufficiently by the YIG-preselector, if available.)
Remote command:
INPut<ip>:FILTer:HPASs[:STATe]
on page 87
YIG-Preselector
Enables or disables the YIG-preselector, if available on the connected instrument.
Note that the YIG-preselector is active only on frequencies greater than 8 GHz. There-
fore, switching the YIG-preselector on or off has no effect if the frequency is below that
value.
In order to make use of the optional 90 GHz frequency extension (R&S VSE-B90G),
the YIG-preselector must be disabled.
Remote command:
INPut<ip>:FILTer:YIG[:STATe]
on page 88
Capture Mode
Determines how data from an oscilloscope is input to the R&S VSE software.
This function is only available for a connected R&S oscilloscope with a firmware ver-
sion 3.0.1.1 or higher (for other versions and instruments the input is always I/Q data).
"I/Q" The measured waveform is converted to I/Q data directly on the R&S
oscilloscope (requires option K11), and input to the R&S
VSE soft-
ware as I/Q data.
For data imports with small bandwidths, importing data in this format
is quicker. However, the maximum record length is restricted by the
R&S oscilloscope. (Memory options on the R&S oscilloscope are not
available for I/Q data.)
Input and Frontend Settings