Keysight x-series Programmer's Reference

3 VMA Mode
3.10 Spurious Emissions Measurement
traces is used. This provides a method to reduce spurs that are internally generated
within the VXT, but you should note the following when using Software Preselection:
–
There is some speed cost due to the need to take multiple captures
–
Taking the point with the lowest amplitude in each trace will make the average
noise level lower at all points that do not have a spur. This can reduce the
accuracy of the measurement of noise and noise-like signals
Because of the difficulty in identifying spurs manually, you are recommended to
leave Software Preselection ON at all times in VXT models M9410A/11A. If you turn it
off in order to speed up your measurement or improve noise accuracy, be aware of
unwanted onscreen spurs.
Remote Command
[:SENSe]:POWer[:RF]:SWPResel:STATe 0 | 1 | ON | OFF
[:SENSe]:POWer[:RF]:SWPresel:STAT?
Example
:POW:SWPR:STAT 1
:POW:SWPR:STAT?
Dependencies Only appears in N9041B, N9042B+V2050A, VXT models M9410A/11A and M9410E/11E. Does not
appear in all measurements
Couplings Affects Sweep Time
Auto Tune supports Software Preselection, so Auto Tune should be performed after setting the
Software Preselection state
Preset
N9041B
OFF
N9042B+V3050A
ON
M9410A/11A
ON
State Saved Saved in instrument state
SW Preselection Type
Specifies the algorithm used for software preselection.
Two hidden sweeps occur in succession. The second sweep is offset in LO frequency
by 2 * IF / N. For each point in each trace, the smaller amplitude from the two traces
is taken and placed in that point in the selected trace. The Peak detector is auto-
selected to improve the image suppression effectiveness. Responses of each trace
that lie on top of one another will remain and are valid signals. Other signals are
images, which are suppressed. The action of taking the smaller of the two traces will
make the average noise level lower in all points that do not have an image, thus
reducing the accuracy of the measurement of noise and noise-like signals.
1649 Vector Modulation Analyzer Mode User's &Programmer's Reference

Keysight x-series Specifications

General

Analysis Bandwidth	Up to 1 GHz (depending on model)
Real-Time Bandwidth	Up to 1 GHz (depending on model)
Form Factor	Benchtop
Connectivity	LAN, USB, GPIB
Resolution Bandwidth	1 Hz to 10 MHz (depending on model)