R&S 1129.7246.03, Operating Manual

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R&S ESU Remote Control – Programming Examples
More Complex Programming Examples
7.10 Operating Manual 1302.6163.12 - 03
status = viWrite(analyzer, "FREQ:SPAN 1MHz", 14, retCnt)
'Span
status = viWrite(analyzer, "BAND:RES 30kHz", 14, retCnt)
'Resolution bandwidth
status = viWrite(analyzer, "INIT;*WAI", 9, retCnt)
'Perform sweep with sync
'--------- Measure 60 dB value ------------------------------
status = viWrite(analyzer, "CALC:MARK:PEXC 6DB", 18, retCnt)
'Peak excursion
status = viWrite(analyzer, "CALC:MARK:STAT ON", 17, retCnt)
'Marker1 on
status = viWrite(analyzer, "CALC:MARK:TRAC 1", 16, retCnt)
'Assign marker1 to trace1
status = viWrite(analyzer, "CALC:MARK:MAX", 13, retCnt)
'Set marker1 to 100 MHz
status = viWrite(analyzer, "CALC:MARK:FUNC:NDBD 60dB", 24, retCnt)
'Read out bandwidth measured
status = viWrite(analyzer, "CALC:MARK:FUNC:NDBD:RES?", 24, retCnt)
'at 60 dB
status = viRead(analyzer, result$, 100, retCnt)
result60 = Val(result$)
'--------- Measure 3 dB Down value --------------------------
status = viWrite(analyzer, "CALC:MARK:FUNC:NDBD 3dB", 23, retCnt)
'Read out bandwidth measured
status = viWrite(analyzer, "CALC:MARK:FUNC:NDBD:RES?", 24, retCnt)
'at 60 dB
status = viRead(analyzer, result$, 100, retCnt)
result3 = Val(result$)
'--------- Read out shape factor-----------------------------
Print "Shapefaktor 60dB/3dB: ";result60/result3
END SUB
REM ************************************************************************
7.3.1.3 Measuring the Third Order Intercept Point
The third order intercept point (TOI) is the (virtual) level of two adjacent useful signals
at which the intermodulation products of third order have the same level as the useful
signals.
The intermodulation product at f
S2
is obtained by mixing the first harmonic of the
useful signal P
N2
with signal P
N1
, the intermodulation product at f
S1
by mixing the first
harmonic of the useful signal P
N1
with signal P
N2
.
f
S1
= 2 × f
n1
– f
n2
(75)
f
S2
= 2 × f
n2
– f
n1
(76)
The following example is based on two adjacent signals with a level of –30 dBm at
100 MHz and 110 MHz. The intermodulation products lie at 90 MHz and 120 MHz
according to the above formula. The frequency is set so that the examined mixture
products are displayed in the diagram. Otherwise, the default setting of the
R&S ESU is used for measurements (SetupInstrument).