Table of Contents
Advertisement
Zero Drift of Sensors
Power sensor dependent (refer to Table 1-3).
Measurement Noise
Power sensor dependent (refer to Table 1-2 and Table 1-3).
Averaging effects on measurement noise. Averaging over 1 to 1024
readings is available for reducing noise. Table 1-3 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 an HP 8481D power sensor in normal mode with the
number of averages set to 4, the measurement noise is equal to:
Number of
Averages
Noise Multiplier
(Normal Mode)
Noise Multiplier
(x2 mode)
HP EPM-441A/442A Service Guide
(<45 pW x 2.75) = <124 pW
Table 1-2: Noise Multiplier
1
2
4
8
5.5
3.89
2.75
1.94
6.5
4.6
3.25
2.3
Power Meter Supplemental Characteristics
16
32
64
128
1.0
0.85
0.61
0.49
1.18
1.0
0.72
0.57
Specifications
256
512
1024
0.34
0.24
0.17
0.41
0.29
0.2
1-7
Advertisement
Table of Contents
