SEPTENTRIO PolaRx5S, User Manual

Page: 57 / 107

5.3. SBF2 I SMR PROGRAM
Not-Applicable Values
Not-applicable columns or fi elds for which the value is unknown contain the ‘ nan ’
(not-a-number) string.
S4 index
The total S4 (columns 8, 33 and 47) is the standard deviation of the 50 Hz raw signal power
normalized to the average signal power over the last minute.
The S4 correction (columns 9, 34 and 48) accounts for the thermal noise contribution in the
total S4.
The corrected S4 (i.e. without the thermal noise contribution) can be computed as follows:
X
=
S
4
2
total
−
S
4
2
correction
S
4
corrected
=
(
√
X if X >
0
0 if
X
≤ 0
Phi xx indices
The Phi xx indices (columns 10 to 14, 35 to 39 and 49 to 53) contain the standard deviation,
in radians, of the 50 Hz detrended carrier phase averaged over intervals of 1, 3, 10, 30 and
60 seconds. More speci
fi cally:
• Phi01 is the average of the 60 standard deviations computed over 1-s intervals during
the last minute.
•
Phi03 is the average of the 20 standard deviations computed over 3-s intervals during
the last minute.
• Phi10 is the average of the 6 standard deviations computed over 10-s intervals during
the last minute.
• Phi30 is the average of the 2 standard deviations computed over 30-s intervals during
the last minute.
• Phi60 is the standard deviation computed over the whole last minute.
The phase detrending is done by fi ltering the raw 50 Hz carrier phase measurements by a
6th order Butterworth high-pass fi lter. The cuto ff frequency of that fi lter is user selectable
with the
-c
option of
sfb2ismr
.
Code-Phase Divergence
Columns 15-16, 40-41and 54-55 report the average value and the standard deviation of the
di
ff erence between the pseudorange and the carrier phase measurements over the last
minute.
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