WILLTEK 4400 Mobile Phone Tester Series, Руководство пользователя

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Chapter 8 SCPI
The Measurement subsystems
4460 GSM System Option and 4468 EDGE System Option Version 12.20
357
internally. Therefore, any attempt to read out data again (unless any measure-
ment has been started before) will result in a timeout and thus in an error
message.
This is one of the main differences between the
[:CONTinuous]
and the
:ARRay
command element.
Note: Any measurement will be terminated if a new MEASure command of the
same or related type is issued (see Notes in section “The MEASure subsystem” on
page 353 for details).
How to convert a result string back into numeric variables
The example program below illustrates how the returned string can be converted
back into numeric variables in a RAPID! program.
Syntax MEASure:ARRay<{:measProp}>[?] <numMeas>
Parameters numMeas
is the number of measurements to be performed.
Description
Takes a
numMeas
number of measurements of the specified type
measProp
.
The results of the single measurements will be stored in an internal array.
The measurement results array can be read out using the related command of the
FETCh subsystem (see examples below for reference).
After an array has been read out using the related
FETCh
command, the internal
array will be cleared. Any subsequent
FETCh
command trying to read out the same
measurement result array will not be able to read any measurement results and thus
result in a timeout. In this case, an error message will be added to the 4400’s internal
error queue (for further details, refer to section
“:MEASure[:CONTinuous]” on
page 354 ).
Query
The query form of any
MEAS:ARR
command will start the related measurement the
specified number of times. After the number of measurements specified have been
performed, the measurement will be stopped.
The query will then return a string containing all the measurement results. The single
result values will be separated by commas.
Any subsequent
FETCh
command trying to read out the same measurement result
array will not be able to read any measurement results and thus result in a timeout.
In this case, an error message will be added to the 4400’s internal error queue (for
further details, refer to section
“:MEASure[:CONTinuous]” on page 354 ).
Examples :MEASure:GSM:ARRay:RFTX:PPEAk 10
This command will make the 4400 perform 10 independent measurements of the
maximum phase error in GSM.
After those 10 results have been achieved, the measurement will be stopped.
The ten result values will be stored in an internal array.
To read out the measurement result array, use the
FETCh
subsystem:
:FETCh:GSM:RFTX:PPEAK?
will return the 10 values in one string (like
“5.42,5.44,5.80,...5.72,5.64”
)
Any subsequent
:FETCh:GSM:RFTX:PPEAK?
command will result in a timeout.
MEASure:GSM:ARRay:RFTX:ALL? 2
This command takes all relevant RFTX measurements twice. The measurements will be
stopped as soon as the 2 x 19 result values are available.
The 38 result values will be returned as a string; the single values will be separated by
commas.
Any subsequent
:FETCh:GSM:RFTX:PPEAK?
command will result in a timeout.