Keysight N1913, Руководство по обслуживанию

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1 Specifications and Characteristics
30 Keysight N1913/1914A Service Guide
Power Meter Supplemental Characteristics
Zero Drift of Sensors
This parameter is also called long term stability and is the change in the power
meter indication over a long time (within one hour) at a constant temperature
after a 24-hour warm-up of the power meter.
Power sensor dependent (refer to
Table 1-4 ).
Measurement Noise
Power sensor dependent (refer to Table 1-3 and Table 1-4 ).
Averaging effects on measurement noise. Averaging over 1 to 1024 readings is
available for reducing noise. Table 1-4 provides the measurement noise for a
particular power sensor with the number of averages set to 16 for normal mode
and 32 for x2 mode. Use the “Noise Multiplier” for the appropriate mode (normal
or x2) and number of averages to determine the total measurement noise value.
For example, for a Keysight 8481D power sensor in normal mode with the number
of averages set to 4, the measurement noise is equal to:
(<45 pW × 2.75) = <124 pW
Table 1-3 Noise multiplier
Number of averages 1 2 4 8 16 32 64 128 256 512 1024
Noise multiplier
(Normal mode)
5.5 3.89 2.75 1.94 1.0 0.85 0.61 0.49 0.34 0.24 0.17
Noise multiplier
(x2 mode)
6.5 4.6 3.25 2.3 1.63 1.0 0.72 0.57 0.41 0.29 0.2
Table 1-4 Power sensor specifications
Power sensor
Zero drift
[a]
Measurement
[b]
noise
Keysight 8481A
[d]
<±10 nW <110 nW
Keysight 8481B
[d]
<±10 mW <110 mW
Keysight 8481D
[d]
<±4 pW <45 pW