Operating instructions

More Complex Programming Examples R&S ESCI
1166.6004.12 7.20 E-1
Phase and Phase Noise Measurement
During phase noise measurement the noise power referred to 1 Hz is brought into proportion to the
power of an adjacent carrier signal. The spacing often used between the measured frequency and the
carrier frequency is 10 kHz.
For the noise measurement the measured absolute level is referred to a bandwidth of 1 Hz.
The following example is again based on a signal with a level of –30 dBm at 100 MHz. Two markers are
used to determine the noise and the phase noise at an offset of 10 kHz from the carrier signal.
REM ************************************************************************
Public Sub Noise()
result$ = Space$(100)
'--------- R&S ESCI default setting ----------------------------------------
----
CALL SetupStatusReg 'Configure status register
CALL IBWRT(receiver%,"*RST") 'Reset instrument
CALL IBWRT(receiver%,"INIT:CONT OFF") 'Single sweep
'--------- Set frequency ---------------------------------------------------
CALL IBWRT(receiver%,"FREQUENCY:CENTER 100MHz") 'Center frequency
CALL IBWRT(receiver%,"FREQ:SPAN 100 kHz") 'Span
'--------- Set level -------------------------------------------------------
CALL IBWRT(receiver%,"DISP:WIND:TRAC:Y:RLEV –20dBm") 'Reference level
CALL IBWRT(receiver%,"INIT;*WAI") 'Perform sweep with sync
'--------- Set reference point ---------------------------------------------
CALL IBWRT(receiver%,"CALC:MARK:PEXC 6DB") 'Peak excursion
CALL IBWRT(receiver%,"CALC:MARK:STAT ON") 'Marker 1 on
CALL IBWRT(receiver%,"CALC:MARK:TRAC 1") 'Assign marker1 to trace1
CALL IBWRT(receiver%,"CALC:MARK:MAX") 'Set marker1 to 100 MHz
CALL IBWRT(receiver%,"CALC:DELT:FUNC:PNO ON") 'Define phase noise
'reference point
'--------- Measure phase noise ---------------------------------------------
CALL IBWRT(receiver%,"CALC:DELT:X 10kHz") 'Set delta marker
CALL IBWRT(receiver%,"CALC:DELT:FUNC:PNO:RES?")'Read out result of
Call ibrd(receiver%, result$) 'phase noise meas.
Print "Phase Noise [dBc/Hz]: "; result$
'--------- Measure noise ---------------------------------------------------
CALL IBWRT(receiver%,"CALC:MARK:X 99.96MHz") 'Set Marker 1
CALL IBWRT(receiver%,"CALC:MARK:FUNC:NOIS:RES?")'Read out result
Call ibrd(receiver%, result$)
Print "Noise [dBm/Hz]: "; result$
END SUB
REM
************************************************************************