Tektronix TekRanger 2 TFS3031, Руководство по обслуживанию

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Performance Check – TekRanger 2 (serial nos. B052000 and above)
4–14
TFS3031 TekRanger/TekRanger 2 Service Manual
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Loss (dB)
Distance (m)
Figure 4–8: Scatter Plot for 50 m Event
Once the data points are gathered, a confidence area can be drawn so that 95
percent of all subsequent data will fall within the area. The suggested area
corresponds to the
1.96-
σ
limits of a Gaussian distribution.
The confidence of the location of each event can then be determined by using
this formula:
Location Confidence = X 2
σ
Where: X = sample mean for all tests.
σ
= sample standard deviation for all tests.
Example: X = 48.045,
σ
= 0.0045.
Location confidence: = 48.045 1.96
δ
= 48.045 1.96 X 0.0045
= 48.045 0.00882
Or,
48.045 - 0.00882 = 48.03618 (lower confidence limit)
48.045 + 0.00882 = 48.05382 (upper confidence limit)