Keysight Technologies N4374B, User Manual

Page: 127 / 164

Definition of Terms
Keysight
N4374B Lightwave Component Analyzer, User’s Guide 125
Average output power uncertainty (optical)
The maximum difference between actual (true) Average output
power (optical) and the nominal (selected) average output
power.
Conditions: After modulator auto bias (“modulator
optimization”) performed with the selected wavelength. Other
conditions as specified.
Measurement: Using an average power meter with averaging
time set to 1 s.
Average power measurement uncertainty (optical)
Maximum difference between measured average (over time)
optical power and true average optical power at the LCA optical
input.
Measurement: Comparison with an average power meter with
averaging time set to 1 s.
Average power measurement range (optical)
The range for the average optical power where the specification
for
Average power measurement uncertainty (optical) applies.
Decibel (dBm, dBo, dBe)
A ratio in decibel (dB) is calculated as 10-log
10
{ratio}. Special
cases:
• dBo: specifically the ratio of optical powers (‘o’ for ‘optical’).
• dBe: specifically the ratio of electrical powers (‘e’ for
‘electrical’).
• dBm: power level related to 1 mW (electrical or optical).
N O TE
Differences of powers in dBm are written as “dBo” for optical powers or
“dBe” for electrical powers.