Agilent Technologies 8504B, Руководство пользователя

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FINAL TRIM SIZE : 7.5 in x 9.0 in
Specications and Regulatory Information
Specications
Return Loss Uncertainty
Description Return loss uncertainty gives the possible range of true return-loss values ,
given a specic measured value . F or example , if the measured return loss
was 057 dB and the uncertainty was +1.8 dB and 01.7 dB , the true return
loss value would lie somewhere between 055.2 dB (057 + 1.8) and 058.7
dB (057 01.7). There are ve factors which contribute to the return loss
uncertainty:
Dynamic accuracy
Sweep-to-sweep repeatability
P olarization sensitivity
Amplitude atness versus mirror position
Dispersion (1550 nm only)
Dynamic accuracy dominates the uncertainty near the noise oor and
becomes increasingly less signicant at higher signal levels . The specied
uncertainty does not include the connector loss or the calibration standard
uncertainty .
The return-loss uncertainty graph for the 1550 nm source applies to the
mirror position range of 0 to 100 mm. The uncertainty is degraded near 080
dB for mirror positions between 100 and 400 mm due to dispersion eects .
Refer to \Characteristics" in this chapter for information on the noise oor .
Specication Return loss uncertainty specication applies with minimum span, averaging
on, and the averaging factor set to 50. F or 1300 nm, the minimum span is 1
mm. F or 1550 nm, the minimum span is 1.2 mm. F or 1550 nm, dispersion
correction must be enabled and the specication applies over the 0 to 100
mm mirror position range .
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