Rohde & Schwarz CMU 200 - Npower (Function Group RF)

CMU RF Measurements
1100.4903.12 6.59 E-10
NPOWer (Function Group RF)
The subsystem NPOWer measures the power of an RF signal using a narrow-band filter with variable
bandwidth. Gaussian filters with bandwidths between 10 Hz and 1 MHz are available. In addition, the
measurement can be performed with the root-raised cosine filter specified in standard TIA/EIA-136.xxx
or with an 1.4 MHz bandpass filter specified for CDMA measurements.
The NPOWer measurement is performed at the frequency set via [SENSe:]RFANalyzer:
FREQuency. The filter bandwidth (RBW) is set via [SENSe:]NPOWer:BWIDth[:RESolution]; it
does not depend on the RBW defined for the POWer and SPECtrum measurement.
The CMU measures the average, maximum and minimum power of the RF signal in a basic evaluation
period comprising a fixed number of samples (4096). In addition to these Current values the minimum
and maximum power in the entire measurement and the average of the average current values, refer-
enced to a statistics cycle, is calculated (see section Measured Values – Subsystem NPOWer? on p.
6.62 ff.). The measurement time depends on the filter bandwidth but never exceeds the order of magni-
tude of 100 ms for a single evaluation period. The frequency of the RF signal is also measured, pro-
vided that is close enough to the measurement frequency set via
[SENSe:]POWer:FREQuency:CENTer. The characteristics of the NPOWer measurement makes it
particularly suitable for the analysis of CW signals where no measurement curves are needed. Com-
pared to the Analyzer Power measurement (subsystem RFANalyzer), it provides a wider range of
filters, additional statistical evaluations and an additional frequency counter.
Note: The configuration of the RF input path ([SENSe:]LEVel:MAXimum,
[SENSe:]LEVel:MODE) and the trigger settings (TRIGger[:SEQuence]:SOURce,
TRIGger[:SEQuence]:THReshold) can have an effect on the NPOWer measurement.
INITiate:NPOWer Start new measurement ⇒ RUN
ABORt:NPOWer Abort measurement and switch off ⇒ OFF
STOP:NPOWer Stop measurement ⇒ STOP
CONTinue:NPOWer Next measurement step (only counting mode) ⇒ RUN
Description of command FW vers.
These commands have no query form. They start or stop the measurement, setting it to the status
given in the top right column.
V3.07
CONFigure:NPOWer:EREPorting <Mode> Event Reporting
<Mode> Description of parameters Def. value Def. unit FW vers.
SRQ |
SOPC |
SRSQ |
OFF
Service request
Single operation complete
SRQ and SOPC
No reporting
OFF – V3.07
Description of command
This command defines the events generated when the measurement is terminated or stopped (event reporting,
see chapter 5 of CMU200 operating manual).