WILLTEK 4400 Mobile Phone Tester Series, Руководство пользователя

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Appendix A SCPI Command Reference
MEASure subsystem
554
4460 GSM System Option and 4468 EDGE System Option Version 12.20
Description
Starts a continuous measurement of the most important EGPRS RF TX tests. To read
out the latest measurement results, use the
:FETCh:EGPRs:RFTX:ALL
com-
mand. The RF TX tests performed by this command are:
ERMS
, the error vector magnitude rms-averaged over a burst.
EVM
is a relative value and shown as a percentage.
EPEAk
, the maximum error vector magnitude within a burst.
EVM
is indicated in per cent.
ENFTh
, the error vector magnitude that is not exceeded by 95 % of the symbols of a
burst. The 95 % EVM is shown in %.
EOFFset, the origin offset indicates the accuracy of the i/Q modulators DC setup; it is
usually an undesire leakage produced due to a DC offset in the phones I/Q modulator.
It is measured in dBc,
FREQuency
means the frequency error of the mobile under
test.
LENGth
the length of the burst in microseconds.
UTIMe
stands for the timing error of the mobile under test in microseconds (taking
the ordered timing advance into account).
POWer
is the mobile's RF output power level in dBm.
TEMPlate
indicates whether the power-time template has been violated by a burst
or not.
CORNer
gives the RF power level in dBm at eight predefined positions of a burst (see
section Corner Points for details).
Notes : Please keep in mind that the start of a new RF TX test will always terminate
the preceding one instantly. For further details regarding group measurements and
their specific advantages, refer to section
:MEAS:...:GROup
. For
[:CONTinu-
ous]
measurements in general, check with section
:MEASure:EGPRs[:CON-
Tinuous]
. For a further description of the single measurements, see description of
the related commands below.
Query
The query form of this command starts the measurements and - after all measure-
ments have been completed and all measurement results obtained - delivers a string,
containing 17 measurement result values, separated with commas. The order and
type of these measurement result values delivered back is as follows:
1.
ERMS
, the error vector magnitude rms-averaged over a burst.
EVM
is a relative
value and shown as a percentage,
2.
EPEAk
, the maximum error vector magnitude within a burst.
EVM
is indicated per
cent,
3.
ENFTh
, the error vector magnitude that is not exceeded by 95% of the symbols of
a burst. The 95%
EVM
is shown in %,
4.
EOFFset
, the origin offset indicates the accuracy of the i/Q modulators DC setup;
it is usually an undesire leakage produced due to a DC offset in the phones I/Q modu-
lator. It is measured in dBc,
5.
FREQuency
, floating point real number representing the mobile's frequency
error,
6.
LENGth
, floating point real number representing the length of the burst in micro-
seconds,
7.
UTIMe
, floating point real number representing the timing error of the mobile
under test in microseconds (taking the ordered timing advance into account),
8.
POWer
, floating point real number representing the mobile's RF output power level
in dBm,
9.
TEMPlate
boolean number. A
0
indicates that the power-time template (PTT)
was not violated by the last burst measured, while a
1
means that the burst did vio-
late the PTT.
10...17.
CORNer
, eight floating point real numbers, representing the RF power level
in dBm at eight predefined positions of a burst.