Keysight Technologies N774 C Series, Руководство пользователя

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Keysight N774xC Series Multiport Power Meter User’s Guide 43
Definition of Terms
3
Dynamic range (logging mode)
For a fixed power meter range, dynamic range D specifies the difference
between the maximum displayable value P
max
in dBm in the corresponding
power meter range and the minimum measurable power P
min
in dBm.
Conditions: As specified.
Measurement: P
max
is 3 dB above the nominal power meter range value
(that is, in the +0 dBm power meter range P
max
is +3 dBm), except for the
+10 dBm range with P
max
= +10 dBm. P
min
, dBm is calculated as the
root-sum-square (RSS) of the specified “Noise 2 sigma (dark)” (see, Noise
2 sigma (dark) on page 44 and “Drift (dark)” (see, Drift (dark) on page 42.
RSS is calculated in linear units (Watts).
Frequency Response
Specifies the frequency f
resp
up to which the power meter's transfer
function is above a defined cutoff level.
The transfer function is the measured optical amplitude on a modulated
sinusoidal optical input divided by the actual amplitude over modulation
frequency, expressed in dB.
Conditions: Cutoff level as specified. Other conditions as specified.
Linearity
Specifies the relative difference between the measured (displayed) power
ratio D
x
/D
0
and the actual (true) power ratio P
x
/P
0
, caused by changing
the power level from the reference level P
0
to an arbitrary level P
x
.
Powers expressed in Watts.
Excluding “Noise pp (dark)” (see, Noise pp (dark) on page 44 and “Drift
(dark)” (see, Drift (dark) on page 42).
Conditions: Reference power level P
0
= 0.01 mW (-20 dBm). Other
conditions as specified.