DGP000814AAA
2-01
H-20
SBAS Correction Data Files
GSS6100 and SimCHAN user manual
© Spirent Communications Plc 2005 - 2007
In this example 1 GEO is assumed with a PRN of 120. It is positioned
directly over the equator with a longitude of 80º WEST. The distance from
the satellite to the centre of the earth is assumed to be 42.164174*10
6
metres. The 2 bits of data ID are both set to 0 and the satellite is assumed
healthy with all 8 health and status bits set to 0 also. This message type is
divided into 3, 67 bit segments with each segment describing almanac data
for 1 GEO satellite. The remaining 11 bits of the message detail the Time Of
Day in seconds. Unused GEO almanac segments are prescribed a PRN
value of 0 and all remaining segment bits are set to alternate 1’s and 0’s.
Parameter Value
No.
Bits
Bit Positions
Binary data
Data ID
0
2
15..16
00
1) PRN number
120
8
17..24
01111000
Health Good
8
25..32
00000000
X
G
(ECEF)
7.32134535*10
6
15
1
33..47
000101100000000
Y
G
(ECEF)
-41.5236736*10
6
15
1
48..62
100000110011110
Z
G
(ECEF)
0 metres
9
1
63..71 000000000
X
G
dt
(ECEF)
0 metres/sec
3
1
72..74 000
Y
G
dt
(ECEF)
0 metres/sec
3
1
75..77 000
Z
G
dt
(ECEF)
0 metres/sec
4
1
78..81 0000
Data ID
0
2
82..83
00
2) PRN number
0
8
84..91
00000000
NOT used
Alternate 1’s & 0’s
57
92..148
1010..1010
Data ID
0
2
149..150
00
3) PRN number
0
8
151..158
00000000
Not used
Alternative 1’s & 0’s
57
159..215
1010..1010
TOD (time of day)
640 seconds
11
216..226
00000001010
1
Denotes a 2’s complement number
The complete contiguous 212 bit data block and its hexadecimal equivalent
is shown below:
0001 1110 0000 0000 0000 0101 1000 0000 0100 0001 1001
1110 0000 0000 0000 0000 0000 0000 0000 0101 0101 0101
0101 0101 0101 0101 0101 0101 0101 0101 0101 0101 0101
0100 0000 0000 1010 1010 1010 1010 1010 1010 1010 1010
1010 1010 1010 1010 1010 1010 1000 0000 1010
Hex:
1E 00 05 80 41 9E 00 00 00 05 55 55 55
55 55 55 54 00 AA AA AA AA AA AA AA 80 A
H.1.2.16 Example of Message Type 26: Ionospheric Delay Corrections
This message contains data for ionospheric delay corrections, for the
relevant ionospheric mask bands and enabled grid points (IGPs) in these
bands. The data for the vertical ionospheric corrections (15 per message) is
determined using the GPS ionospheric parameters defined in the GPS
constellation file, and the ionospheric correction model defined in STANAG
4294/ICD-GPS-200C. If the calculated ionospheric delay is greater than the