Keysight N774-C & 8162-C Series User’s Guide
63
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 based on the nominal power meter range value.
P
max
is 3 dB higher than this value (that is, in the +0 dBm power meter
range, P
max
is +3 dBm), except that it equals the value for the highest
range. P
min
dBm is calculated as the root-sum-square (RSS) of the
specified “Noise 2 sigma (dark)” (see,
“Drift (dark)” (see,
on page 62). 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,
(dark)” (see,
Conditions:
Reference power level P
0
= 0.01 mW (-20 dBm). Other
conditions as specified.