Output Power Commands

These commands control the output power meter parameters.

Numerical Choice:

IO[1]|2|3|4|5|6|7|8 – Refer to the block diagram for your system configuration to determine the input or output block that you want to configure.

POWer[1]|2|3|4|5|6|7|8|9|10|11|12 – The signal channel selection for an output power meter depends on the current configuration and the output block specified in the command. When you choose a configuration, the PXB creates one or more signal channels with a mixture of BBG, fading and summing functions. Each signal channel is assigned a unique number. For a specified output IO block, you can only specify signal channels that feed into that block. Specifying an invalid power meter (POWer) number will result in an error. For example, in a 2x2 MIMO configuration, the output IO 2 block receives input from two signal channels: 2 (Fader 2 in the block diagram) and 4 (Fader 4 in the block diagram). So, for 2x2 MIMO, the only valid POWer numerical choices for CONTrol:IO2:OUTPut are POWer2 and POWer4.

:CONTrol:IO[1]|2|3|4|5|6|7|8[:OUTPut]:POWer[1]|2|3|4|5|6|7|8|9|10|11|12:ARMS?

This command queries the RMS baseband output power.

The value returned is expressed in dBm with a resolution of 1E-6.

Range: – 276 to 20

:CONTrol:IO[1]|2|3|4|5|6|7|8[:OUTPut]:POWer[1]|2|3|4|5|6|7|8|9|10|11|12:DURation <val>

:CONTrol:IO[1]|2|3|4|5|6|7|8[:OUTPut]:POWer[1]|2|3|4|5|6|7|8|9|10|11|12:DURation?

This command sets the total time to collect power meter samples and average them to calculate the baseband output power.

The variable <val> is expressed in seconds with a resolution of 0.0001.

This setting does not wait for valid samples to appear before it starts running, so it is possible to set the power meter measurement so that no valid samples are measured (e.g., with a low duty-cycle waveform and a short measurement time, in which case there is a high probability that the power meter result with be -276 dBm). Increasing the power meter measurement time will ensure the capture of valid samples in the measurement.

Range: 0 to 2748.77

:CONTrol:IO[1]|2|3|4|5|6|7|8[:OUTPut]:POWer[1]|2|3|4|5|6|7|8|9|10|11|12:HCOunt <val>

:CONTrol:IO[1]|2|3|4|5|6|7|8[:OUTPut]:POWer[1]|2|3|4|5|6|7|8|9|10|11|12:HCOunt?

This command sets the holdoff sample count, or the number of consecutive waveform samples that must meet or exceed the threshold voltage level before the waveform sample is used to determine the baseband output power. If the number of consecutive waveform samples is not met, the sample voltages are not used. This setting is useful if the waveform has an inconsistent structure or to eliminate glitches.

The variable <val> is expressed in samples and the samples are counted at a 200 MHz rate.

This command is only valid when Power Meter Gating is set to Threshold (:CONTrol:IO[1]|2|3|4|5|6|7|8[:OUTPut]:POWer[1]|2|3|4|5|6|7|8|9|10|11|12:PMGating THReshold).

Range: 0 to 216 – 1

:CONTrol:IO[1]|2|3|4|5|6|7|8[:OUTPut]:POWer[1]|2|3|4|5|6|7|8|9|10|11|12:MARKer M1|M3|M4

:CONTrol:IO[1]|2|3|4|5|6|7|8[:OUTPut]:POWer[1]|2|3|4|5|6|7|8|9|10|11|12:MARKer?

This command selects the marker to use for selecting samples for averaging to calculate the baseband output power.

This command is only valid when Power Meter Gating is set to Marker (:CONTrol:IO:[1]2|3|4|5|6|7|8[:OUTPut]:POWer:PMGating MARKer).

:CONTrol:IO[1]|2|3|4|5|6|7|8[:OUTPut]:POWer[1]|2|3|4|5|6|7|8|9|10|11|12:PMGating THReshold|MARKer

:CONTrol:IO[1]|2|3|4|5|6|7|8[:OUTPut]:POWer[1]|2|3|4|5|6|7|8|9|10|11|12:PMGating?

This command sets the power meter gating, or the reference to be used for selecting waveform samples to determine the baseband output power.

THReshold	This choice selects the threshold as the reference for power meter gating. Power observations are only accumulated if they are greater than or equal to the specified threshold, and if the number of consecutive observations below the threshold has exceeded the holdoff sample count value.
MARKer	This choice uses the marked samples as the reference for power meter gating. Power observations are only accumulated for marked samples according to the specified marker selection.

:CONTrol:IO[1]|2|3|4|5|6|7|8[:OUTPut]:POWer[1]|2|3|4|5|6|7|8|9|10|11|12:SAVerage?

This query reports the number of samples that were used in calculating the average baseband output power. When the internal waveform is measured, the PXB measures samples for the specified power meter averaging time to calculate the mean RMS voltage for the subsequent power calibration.

The variable <val> is expressed as an integer.

:CONTrol:IO[1]|2|3|4|5|6|7|8[:OUTPut]:POWer[1]|2|3|4|5|6|7|8|9|10|11|12:SEQuence:ALL:CONTrol M1|M3|M4

:CONTrol:IO[1]|2|3|4|5|6|7|8[:OUTPut]:POWer[1]|2|3|4|5|6|7|8|9|10|11|12:SEQuence:SEGMent[1]|2:CONTrol?

Gets or sets the segment control signal for all segments in the sequence. The control signal rising edge is the control signal trigger event and the time segment begins the specified number of integration time slots offset from that event. The control signal shall remain high for the duration of the time segment and must go low again before the next time segment can begin.

Default: M1

M1	Marker 1
M3	Marker 3
M4	Marker 4

:CONTrol:IO[1]|2|3|4|5|6|7|8[:OUTPut]:POWer[1]|2|3|4|5|6|7|8|9|10|11|12:SEQuence:ALL:WINDow

:CONTrol:IO[1]|2|3|4|5|6|7|8[:OUTPut]:POWer[1]|2|3|4|5|6|7|8|9|10|11|12:SEQuence:SEGMent[1]|2:WINDow?

Gets or sets the integration time slot in seconds for all segments in the sequence.

All integration time slots within a sequence must be integer multiples of the smallest integration time slot.

Default: 1E-3

Range: 1E-6 to 1E-3

:CONTrol:IO[1]|2|3|4|5|6|7|8[:OUTPut]:POWer[1]|2|3|4|5|6|7|8|9|10|11|12:SEQuence:COUNt?

Gets the number of segments in the sequence.

Default: 2

Range: 2 to 2

:CONTrol:IO[1]|2|3|4|5|6|7|8[:OUTPut]:POWer[1]|2|3|4|5|6|7|8|9|10|11|12:SEQuence:RESults:CLEar

Clears the sequence measurement results queue. This is done automatically on PXB Play.

:CONTrol:IO[1]|2|3|4|5|6|7|8[:OUTPut]:POWer[1]|2|3|4|5|6|7|8|9|10|11|12:SEQuence:RESults:NEXT?

Gets the next sequence measurement result and removes it from the queue. The sequence measurement result is returned in the following defined format:

sequence-result:

sequence-number, segment-results;

sequence-number:

An 18-bit sequence occurrence number.
Or, -1 if the queue is empty.

segment-results :

segment-result;
segment-results; segment-result;

segment-result:

aggregate-results

aggregate-results:

aggregate-result
aggregate-results, aggregate-result

aggregate-result:

RMS of one (or more) windows in dBm.

Notes:

The sequence measurement result format is defined with non-terminal symbols shown in italic type and terminal symbols shown in a fixed-width font.
Each symbol is defined on successive indented lines.
When there is more than one possible expansion of a symbol, the alternatives are listed on separate lines.
Note the double semicolon at the end of the sequence measurement result.
The 18-bit sequence number has a range of [0, 262143]. It is incremented between each sequence occurrence, regardless of whether the sequence measurement result is lost because the queue was full. The sequence counter wraps back to zero when it overflows.
The result is returned as an ASCII string in IEEE block data format.

:CONTrol:IO[1]|2|3|4|5|6|7|8[:OUTPut]:POWer[1]|2|3|4|5|6|7|8|9|10|11|12:SEQuence:SEGMent[1]|2:OFFSet

:CONTrol:IO[1]|2|3|4|5|6|7|8[:OUTPut]:POWer[1]|2|3|4|5|6|7|8|9|10|11|12:SEQuence:SEGMent[1]|2:OFFSet?

Gets or sets the number of windows (integration time slots) after the segment control signal event to start the measurement for each segment in the sequence.

Default: 0

Range: 0 to 1E3

:CONTrol:IO[1]|2|3|4|5|6|7|8[:OUTPut]:POWer[1]|2|3|4|5|6|7|8|9|10|11|12:SEQuence:SEGMent[1]|2:COUNt

:CONTrol:IO[1]|2|3|4|5|6|7|8[:OUTPut]:POWer[1]|2|3|4|5|6|7|8|9|10|11|12:SEQuence:SEGMent[1]|2:COUNt?

Gets or sets the number of windows (integration time slots) for each segment in the sequence.

Default: 10

Range: 1 to 1E2

:CONTrol:IO[1]|2|3|4|5|6|7|8[:OUTPut]:POWer[1]|2|3|4|5|6|7|8|9|10|11|12:SEQuence:SEGMent[1]|2:RAGGregate

:CONTrol:IO[1]|2|3|4|5|6|7|8[:OUTPut]:POWer[1]|2|3|4|5|6|7|8|9|10|11|12:SEQuence:SEGMent[1]|2:RAGGregate?

Gets or sets the number of windows (integration time slots) to be aggregated when reporting results for each segment.

This setting specifies an integer value such that the segment power is reported as an aggregate power over multiple windows taken N windows at a time where N is the aggregation count. If the segment is not an integer multiple of the results aggregation count, the last aggregation contains the residue.

Default: 1

Range: 1 to 10

:CONTrol:IO[1]|2|3|4|5|6|7|8[:OUTPut]:POWer[1]|2|3|4|5|6|7|8|9|10|11|12:STATe ON|OFF|1|0

:CONTrol:IO[1]|2|3|4|5|6|7|8[:OUTPut]:POWer[1]|2|3|4|5|6|7|8|9|10|11|12:STATe?

This command turns the power meter measurement on or off while the system is playing.

ON \| 1	This choice turns on the power meter measurement.
OFF \| 0	This choice turns off the power meter measurement.

:CONTrol:IO[1]|2|3|4|5|6|7|8[:OUTPut]:POWer[1]|2|3|4|5|6|7|8|9|10|11|12:THReshold <val>

:CONTrol:IO[1]|2|3|4|5|6|7|8[:OUTPut]:POWer[1]|2|3|4|5|6|7|8|9|10|11|12:THReshold?

This command sets the sample value to be used as the averaging criteria. Only samples above this level are included in the baseband output power calculation.

The variable <val> is expressed in volts with a resolution of 1E-6 V.

This command is only valid when Power Meter Gating is set to Threshold (:CONTrol:IO[1]|2|3|4|5|6|7|8[:OUTPut]:POWer[1]|2|3|4|5|6|7|8|9|10|11|12:PMGating THReshold).

Range: 0 to 1.414214