Novatel OM-20000041 Manual Do Utilizador
D
Logs summary
214
MiLLennium GPSCard Software Version 4.50 Command Descriptions Manual Rev 1
SBTA/B
SATELLITE BROADCAST DATA: RAW SYMBOLS
This message contains the satellite broadcast data in raw symbols before FEC decoding or any other processing.
An individual message is sent for each PRN being tracked. For a given satellite, the message number increments
by one each time a new message is generated. This data matches the RBTA/B data if the message numbers are
equal. The data must be logged with the ’onnew’ trigger activated to prevent loss of data.
An individual message is sent for each PRN being tracked. For a given satellite, the message number increments
by one each time a new message is generated. This data matches the RBTA/B data if the message numbers are
equal. The data must be logged with the ’onnew’ trigger activated to prevent loss of data.
SBTA
Structure:
SBTB
Format:
Message ID = 53
Message byte count = 168
$SBTA
week
seconds
prn
cstatus
message #
# of symbols
raw symbols
*xx
[CR][LF]
Field #
Field type
Data Description
Example
1
$SBTA
Log header
$SBTA
2
week
GPS week number
883
3
seconds
GPS seconds into the week
413908.000
4
prn
PRN of satellite from which data originated
120
5
cstatus
Channel Tracking Status
80812F14
6
message #
Message sequence number
119300
7
# of symbols
Number of symbols transmitted in the message. At present,
always equals 256 symbols.
always equals 256 symbols.
256
8
raw symbols
256 symbols compressed into a 128 bytes, i.e. 4 bits/symbol.
Hence, 256 hex characters are output. If FEC decoding is
enabled, soft symbols are output with values ranging from E
to 3 where 3’s represent binary 1 and E’s represent binary 0
output.
Hence, 256 hex characters are output. If FEC decoding is
enabled, soft symbols are output with values ranging from E
to 3 where 3’s represent binary 1 and E’s represent binary 0
output.
EE33EEEE33333E33EE33EEEE33
333E33EE33EEEE33333E33EE33E
EEE33333EEEE3333EEE33E33E3
EE33EEE3EEEE33EE3E3EEEEEE
EEEEEEEE3333EEE33EEEEE33E
E3EEE3E3EE3EE33EEE33E333EE
3333E3E3333E33E3333EEEEE333
EE3E3333EE3EE3EE33EE3EE3EE
3E33E33E3EEE33333E3333E33E3
E333E3E33333E3EEE3E3E
333E33EE33EEEE33333E33EE33E
EEE33333EEEE3333EEE33E33E3
EE33EEE3EEEE33EE3E3EEEEEE
EEEEEEEE3333EEE33EEEEE33E
E3EEE3E3EE3EE33EEE33E333EE
3333E3E3333E33E3333EEEEE333
EE3E3333EE3EE3EE33EE3EE3EE
3E33E33E3EEE33333E3333E33E3
E333E3E33333E3EEE3E3E
9
*xx
Checksum
*4C
10
[CR][LF]
Sentence terminator
[CR][LF]
Field #
Data
Bytes
Format
Units
Offset
1
Sync
3
char
0
(header)
Checksum
1
char
3
Message ID
4
integer
4
Message byte count
4
integer
bytes
8
2
Week number
4
integer
weeks
12
3
Seconds of week
8
double
seconds
16
4
PRN number
4
integer
1-999
24
5
Channel Status
4
integer
n/a
28
6
Message #
4
integer
n/a
32
7
# of Symbols
4
integer
n/a
36
8
Raw Symbols
128
char
n/a
40