SCPI.CALCulate.PN(Ch).TRACe(Tr).FUNCtion.AVARiance.DATA_Q avg_time, fcutoff, allan_var, jitter

Object Type

Property (Read Only)

Syntax

Value = SCPI.CALCulate.PN(Ch).TRACe(Tr).FUNCtion.AVARiance.DATA_Q avg_time, fcutoff, allan_var, jitter

Description

This command gets Allan Variance and Jitter (data trace), for the selected trace Tr of the selected channel Ch.

Recommendation for each input parameters:

• Cut-off frequency (CutOff) :

• • Range of start offset frequency from stop offset frequency

• Minimum specified average time (Tau) :

• • Choose a value of big one, reciprocal number of stop offset frequency or reciprocal number of cut-off frequency.

• Maximum specified average time (Tau) :

• • It is decided by start offset frequency. Relations of Tau and start offset frequency are as follows.
    

    Start offset Frequency	Specified average time (Tau)
    1 Hz	0.2 sec.
    10 Hz	0.02 sec.
    100 Hz	0.002 sec.
    1000Hz	0.0002 sec.

Variable

Examples

Dim avg_time As Double
Dim fcutoff As Double
Dim allan_var As Double
Dim jitter As Double
Dim var As Variant
avg_time = 0.001 'Tau = 0.001 sec
fcutoff = 10000 '10 kHz cutoff frequency
SCPI.CALCulate.PN.TRACe.FUNCtion.AVARiance.DATA_Q avg_time, fcutoff, allan_var, jitter
MsgBox "Allan Variance = " & Str$(allan_var) & " " & "Jitter(rms) = " & Str$(jitter) & " (sec)"

Related Objects

SCPI.CALCulate.PN(Ch).TRACe(Tr).FUNCtion.AVARiance.MEMory

Equivalent Key

No equivalent key is available on the front panel.

Equivalent SCPI Command

Syntax

:CALCulate:PN[1-1]:TRACe[1-1]:FUNCtion:AVARiance:DATA? <avg_time>,<fcutoff>

Query Response

{Allan variance}, {Jitter}<newline><^END>

Example of use

10 OUTPUT 717;":CALCulate:PN1:TRACe1:FUNCtion:AVARiance:DATA? 0.001,10000"
30 ENTER 717;A$