Chapter 8
SCPI
The Measurement subsystems
4460 GSM System Option and 4468 EDGE System Option
Version 12.20
369
Working with complex limits
It is not possible to define all relevant limits by just one number. Some limits are
quite complex, like the power/time template, the corner points or the modulation
spectrum.
Limits for the power/time template
The limits for the power/time template are made up by a total of 16 vectors; 9
for the upper limits and 7 for the lower limits.
These vectors have the following format: x,y.
– where
x
is the time in microseconds in relation to the beginning of the burst
(i.e. the first bit of the useful part)
– and
y
is the RF power level in dB(c) in relation to the nominal output power
level of the mobile.
Examples:
CALC:RFTX:TEMP:LIM:UPP -42,-47,-28,-47,-18,-28,-10,
-4,0,4, 552.8,1,560.8,-4,570.8,-28,580,-47
CALC:RFTX:TEMP:LIM:LOW 0,-150,0,-150,0,-40,20,
-1,270,-1,543,-1,543,-150
Limits for the corner points
The corner points are a maximum of eight positions to check critical parts of the
burst. For each position, a minumum and a maximum RF power level may be
specified.
– Positions are specified in microseconds in relation to the beginning of the
burst (i.e. the first bit of the useful part)
– minimum and maximum RF power levels are specified in dB(c) in relation to
the nominal output power level of the mobile.
Examples:
CALC:RFTX:CORN:POS -28,-18,-10,0,542.8,
552.8,560.8,570.8
CALC:RFTX:CORN:LIM:LOW -150,-150,-150,-150,
-150,-150,-150,-150
Description
Activates or deactivates the check of the measurement results against the limit of the
measurement type defined by
measProp
.
Note:
When the limit evaulation has been switched off, a
:FAIL
query will only
return
0
(s) (pass).
Example
CALCulate:GSM:RFTX:PRMS:LIMit:STATe OFF
This command switches the limit evaluation of the RMS phase error
off
.
MEASure:GSM:RFTX:PRMS
Starts a series of RMS phase error measurements.
CALCulate:GSM:RFTX:PRMS:LIMit:FAIL?
This query of the pass/fail evaluation will always return
0
(pass) as the limit evalua-
tion of this parameter has been switched off.