When Signal Studio is used to download and initiate waveform playback in multiple signal generators, it sends SCPI commands to set up the triggering parameters and initiate the waveform playback so that the playback starts at the same time in each instrument. If you choose to store waveforms in the signal generators and recall them for playback from the signal generator memory, rather than using Signal Studio directly, additional steps are needed to get synchronized waveform playback. The front panel keystrokes in the procedure below can be replaced by SCPI commands in a software program.
First, connect the signal generators as shown in the Tutorials section of the online help for your desired configuration:
Multiple Antennas Solution without Baseband Timing Alignment or RF Phase Coherence for MxN MIMO
Multiple Antennas Solution with Baseband Timing Alignment without RF Coherence for MxN MIMO
Multiple Antennas Solution with Baseband Timing Alignment and RF Phase Coherence for MxN MIMO
Make sure that the EVENT 2 output of the master ESG is connected to the PATT TRIG IN 1 connectors on both the master and slave ESGs. The 10 MHz references should be connected between the instruments.
For each signal generator, press these keys: > > > > > > and verify that is selected. Next, press > and set this to . This will set up the signal generator to start playing back the waveform continuously when it receives an external trigger input on the PATT TRIG IN 1 connector, and to ignore further trigger signals.
On each signal generator, select the desired waveform, but leave the ARB turned off:
Press > > , then select and load the desired segment(s).
Press > , and select the desired waveform file.
Send the following SCPI commands to the master ESG to prepare it to output periodic triggering pulses on the EVENT 2 output. If you are not using a software program to control the test, you can use the Keysight Connection Expert to connect to the signal generator and send the following SCPI commands:
Turn on the ARB in each signal generator: > > (if needed). Set the desired frequency and amplitude for the output signal and turn RF on.
Send these SCPI commands to the master ESG to generate the trigger pulses to start the waveform playback and to stop the pulse generation. No delay is needed between the commands since the hardware works faster than the SCPI command processing.
diag:bbg:mon "ww a6000056 3"
Turning off the Arb on any of the signal generators will cause a loss of synchronization. To re-synchronize the waveform playback or change to a different waveform(s), repeat steps 2-5.
Make sure that the EVENT 1 output from the master MXG/EXG is connected to the PAT TRIG IN on the slave MXG/EXG. If additional slaves are present, the EVENT 1 output of each slave should be connected to the PAT TRIG IN of the next slave in the system. The 10 MHz references should be connected between the instruments.
You can use multiple N5182A signal generators in the same system, or you can use N5172B and N5182B signal generators in the same system. However, you cannot use a mixture of N5182A signal generators and N5172B or N5182B signal generators in the same system.
If you are using an N5172B or N5182B and one or more N5182A signal generators, you must configure the N5172B or N5182B as the Master. In addition, the N5182A slaves must be at the end of the instrument chain.
On the master MXG/EXG, press these keys to set up the trigger type, trigger mode, and trigger source: > > > > > > > . Here you can choose , , or as the trigger source. is convenient for manual operation. trigger can easily be sent with a SCPI command so that is a good choice if the measurement is automated. uses an external trigger signal applied to Patt Trig In 1 (by default), which is the PAT TRIG rear panel connector.
If was selected for the Trigger Source, disconnect the external trigger signal from the PAT TRIG input on the master MXG/EXG.
On the slave MXG/EXG(s), press these keys to set up the trigger type and trigger mode. The default trigger source of Patt Trig will be used: > > > > > . Press these keys to verify that the trigger source is set to , with External defined to be the rear panel Patt Trig In 1 input: > > > > > .
Press these keys to set up the master MXG/EXG for the Multi-BBG Sync function: > > > > > > then
for a N5182A master, set as appropriate.
for an N5172B or N5182B master, set and as appropriate.
On each slave MXG/EXG, press these keys to set up the Multi-BBG Sync function: > > > > > > then
for a N5182A slave, set and as appropriate.
for an N5172B or N5182B slave, set , , and as appropriate.
On each slave MXG/EXG, press .
On the master, press . The status on all MXG/EXGs should show .
In each MXG/EXG, select the desired waveform file and turn ARBS ON: > > > to load the waveform files into the baseband generator memory if needed, then highlight the desired waveform file and press > . Set the desired frequency and amplitude for the output signal and turn RF on.
Initiate the waveform playback using one of these steps, depending on which Trigger Source was selected in step 1:
Trigger Source = Trigger Key: press to start the waveform playback.
Trigger Source = Bus: Send the *TRG SCPI command to the master MXG/EXG. If you are not using a software program to control the test, you can use the Keysight Connection Expert to connect to the signal generator and send the SCPI commands.
Trigger Source = Ext: Connect the external trigger signal to the PAT TRIG input on the master MXG/EXG.
To change waveforms or resynchronize the MXG/EXGs:
If using an external trigger for the master MXG/EXG, disconnect it or turn it off.
Turn off all of the ARBs by pressing > > and press > > on each MXG/EXG.
Repeat steps 6 through 9.