Agilent Technologies 86038A User Manual page 103

Setup Menu
Table 5 Maximum RF Modulation Frequency (MHz) for <90° phase steps
∆τRGD
(ns/nm)
0.1
0.5
1
5
10
50
100
500
1000
5000
10000
50000
Agilent 86038A Optical Dispersion Analyzer, Third Edition
Maximum RF Modulation Frequency (MHZ)
The following table lists recommended modulation frequencies. Any
modulation smaller than that listed will give correct results (that is, no
phase wrapping). Smaller modulation frequencies will have more noise
and better resolution. Table cells that have an arrow symbol (←) indicate
that you must decrease the wavelength increment to achieve the desired
∆τRGD
.
0.001 0.005 0.01
any any any
any any any
any any any
any any any
any any 2500
any 1000 500
2500 500 250
500 100 50
250 50 25
50 10 5
←
25 5
← ←
5
Auto Modulation Frequency
For Stepped mode measurements only!
Automatically selects the modulation frequency to avoid RF phase
wrapping. The amount of RF phase change that is generated in response to
a wavelength increment is determined by the product of the wavelength
increment, the modulation frequency, and the dispersion of the test device.
Automatic adjustment of the modulation frequency ensures that the per-
wavelength-step phase change is always less than ±180 degrees on port 1
only.
Use auto mode if the approximate group delay/dispersion
Tip:
characteristics are not known in advance.
⁄ ( × ∆τ × ∆λ )
f = 1 4
90
∆λ Wavelength Increment (nm)
0.05 0.1 0.5
any any any
any any 1000
any 2500 500
1000 500 100
500 250 50
100 50 10
50 25 5
←
10 5
← ←
5
← ← ←
← ← ←
← ← ←
Function Reference
1 5
2500 500
500 100
250 50
50 10
25 5
←
5
← ←
← ←
← ←
← ←
← ←
← ←
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