Keysight E6640A, Measurement Applications User & Programmer Reference

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8 Channel Power Measurement
Sweep/Control
Relative Trigger Level
Sets the relative trigger level for the RF burst envelope.
In some models, the relative burst trigger function is implemented in hardware. In other models, without
the advanced triggering hardware required, the relative burst trigger function is implemented in software in
some measurements, and is unavailable in other measurements.
When implemented in software, the relative RF Burst trigger function is implemented as follows:
1. The measurement starts with the absolute RF Burst trigger setting. If it cannot get a trigger with that
level, auto trigger fires and the acquisition starts anyway. After the acquisition, the measurement
searches for the peak in the acquired waveform and saves it.
2. Now, in the next cycle of the measurement, the measurement determines a new absolute RF Burst level
based on the peak value from the first measurement and the Relative RF Burst Trigger Level (always 0 or
negative dB) set by the user. The following formula is used:
3. absolute RF Burst level = peak level of the previous acqui relative RF Burst level
4. If the new absolute RF Burst level differs from the previous by more than 0.5 dB, the new level is sent to
the hardware; otherwise it is not updated (to avoid slowing down the acquisition)
Steps 2 and 3 repeat for subsequent measurements.
Key Path
Trigger, RF Burst
Scope Meas Global
Remote Command :TRIGger[:SEQuence]:RFBurst:LEVel:RELative <rel_ampl>
:TRIGger[:SEQuence]:RFBurst:LEVel:RELative?
Example TRIG:RFB:LEV:REL –10 dB
sets the trigger level of the RF burst envelope signal to the relative level of –10 dB
Notes Sending this command does not switch the setting from absolute to relative; to switch it you need to
send the :TRIGger[:SEQuence]:RFBurst:LEVel:TYPE command, above.
The relative trigger level is not available in some measurements. In those measurements the
RELative parameter, and the :TRIGger[:SEQuence]:RFBurst:LEVel:TYPE
command (above), will generate an error if sent.
Dependencies This key is grayed out and Absolute Trigger Level selected if the required hardware is not present in
your analyzer and the current measurement does not support Relative triggering.
Preset –6 dB
GSM: –25 dB
State Saved Saved in instrument state
Min –45 dB
Max 0 dB
Default Unit dB or dBc
Backwards
Compatibility SCPI :TRIGger[:SEQuence]:RFBurst:LEVel
This legacy command is aliased to :TRIGger[:SEQuence]:RFBurst:LEVel:RELative because the PSA
612 W-CDMA & HSPA Measurement Applications Reference