Chapter d. output message library, Ion: ionosphere parameters – Spectra Precision ProMark 800 Reference Manual User Manual
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Chapter D. Output Message Library
ION: Ionosphere Parameters
This message contains the ionosphere and GPS-to-UTC data
conversion parameters.
The message is as follows:
$PASHR,ION,
The message’s binary structure is described in the table
below.
Type
Name Size
Contents
Float
a0
4
Ionospheric parameter (seconds)
Float
a1
4
Ionospheric parameter (seconds/semi-circle)
Float
a2
4
Ionospheric parameter (seconds/semi-circle)
Float
a3
4
Ionospheric parameter (seconds/semi-circle)
Float
b0
4
Ionospheric parameter (seconds)
Float
b1
4
Ionospheric parameter (seconds/semi-circle)
Float
b2
4
Ionospheric parameter (seconds/semi-circle)
Float
b3
4
Ionospheric parameter (seconds/semi-circle)
Double
A1
8
First order terms of polynomial
Double
A0
8
Constant terms of polynomial
Unsigned
long
Tot
4
Reference time for UTC data
Short
Wnt
4
UTC reference week number
Short
DtLS
2
GPS-UTC differences at reference time
Short
WnLSF 2
Week number when leap second became effective
Short
DN
2
Day number when leap second became effective
Short
DtLSF
2
Delta time between GPS and UTC after correction
Short
Wn
2
GPS week number
Unsigned
long
Tow
4
Time of the week (in seconds)
Short
bulwn
2
GPS week number when message was read
Unsigned
long
bultow
4
Time of the week when message was read