Keysight x-series User Manual

3 Spectrum Analyzer Mode
3.4 Occupied BW Measurement
Example
:FREQ:EMIX:CENT 60 GHz
:FREQ:EMIX:CENT?
Notes This command is the same in all Modes, but the parameter is Measurement Global. So, the value is
independent in each Mode and common across all the measurements in the Mode
Couplings When you return to External Mixing after using one of the other inputs (for example, RF), you return to
the settings that you had when you left External Mixing. So, you return to the band you were in with the
Center Frequency that you had. However, Span is not an input-dependent parameter, so it does not
change. Therefore, the instrument comes back with the Span from the previous input, limited as
necessary by the current mixer setup
Preset When Mode Preset is performed while in External Mixing, the start frequency of the current Mode is set
to the nominal Min frequency of the lowest harmonic range in the Harmonic Table for the current mixer
setup. Similarly, the stop frequency of the current Mode is set to the nominal Max frequency of the
highest harmonic range in the Harmonic Table. Center Frequency thus presets to the point arithmet-
ically equidistant from these two frequencies
Note that, if the current measurement has a limited Span available to it, and cannot achieve the span
shown in the table (Span = Stop Freq – Start Freq), the instrument uses the maximum span that the
measurement allows, and still sets Center Frequency to the midpoint of the Start Freq and Stop Freq
values in the Harmonic Table
When Restore Input/Output Defaults is performed, the mixer presets to the 11970A, whose Start and
Stop frequencies are 26.5 and 40GHz respectively. The center of these two frequencies is 33.25 GHz
Therefore, after Restore Input/Output Defaults, if you switch to External Mixing and do a Mode Preset
while in the Spectrum Analyzer Mode, the resulting Center Frequency is 33.25GHz
State Saved Yes
Min The minimum frequency in the currently selected mixer band + 5Hz
Max The maximum frequency in the currently selected mixer band - 5Hz
If the knob or step keys are being used, also depends on the value of the other three interdependent
parameters Span, Start Freq and Stop Freq
Span
Set the frequency of the occupied bandwidth span for the current measurement.
Remote Command
[:SENSe]:OBWidth:FREQuency:SPAN <freq>
[:SENSe]:OBWidth:FREQuency:SPAN?
[:SENSe]:OBWidth:FREQuency:SPAN:AUTO ON | OFF | 0 | 1
[:SENSe]:OBWidth:FREQuency:SPAN:AUTO?
Example
:OBW:FREQ:SPAN 2.4 MHz
:OBW:FREQ:SPAN?
:OBW:FREQ:SPAN:AUTO 0
:OBW:FREQ:SPAN:AUTO?
788 Spectrum 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)