D Logs Summary
180 MiLLennium GPSCard SW Version 4.503/4.52 Command Descriptions Manual Rev 2
POSA/B Computed Position

This log will contain the last valid position and time calculated referenced to the GPSAntenna phase centre. The

position is in geographic coordinates in degrees based on your specified datum (default is WGS84). The height is

referenced to mean sea level. The receiver time is in GPS weeks and seconds into the week. The estimated standard

deviations of the solution and current filter status are also included. See also Section A.3.2 Pseudorange

Algorithms, Page 68.

POSA

Structure:
Example:$POSA,637,511251.00,51.11161847,-114.03922149,1072.436,-16.198,61,26.636,
6.758,78.459,0*12[CR][LF]

POSB

Format: Message ID = 01 Message byte count = 88

$POSA week seconds lat lon hgt undulation datum ID
lat std lon std hgt std sol status *xx [CR][LF]
Field # Type Data Description Example
1$POSA Log header $POSA
2week GPS week number 637
3seconds GPS seconds into the week 511251.00
4lat Latitude of position in current datum, in degrees (DD.dddddddd). A - implies South latitude 51.11161847
5lon Longitude of position in current datum, in degrees (DDD.dddddddd). A + implies West longitude -114.03922149
6hgt Height of position in current datum, in meters with respect to mean sea level (see Figure D-2, Page
187) 1072.436
7undulation Geoidal separation, in meters, where + is above spheroid and - is below spheroid (see Figure C-
6, Page 132)-16.198
8datum ID Current datum ID # (see Table G-2, Page 240)61
9lat std Standard deviation of latitude solution element, in meters 26.636
10 lon std Standard deviation of longitude solution element, in meters 6.758
11 hgt std Standard deviation of height solution element, in meters 78.459
12 sol status Solution status as listed in Table D-1 0
13 *xx Checksum *12
14 [CR][LF] Sentence terminator [CR][LF]
Field # Data Bytes Format Units Offset
1Sync 3char 0
(header) Checksum 1char 3
Message ID 4integer 4
Message byte count 4integer 8
2Week number 4integer weeks 12
3Seconds of week 8double seconds 16
4Latitude 8double degrees (+ is North, - is South) 24
5Longitude 8double degrees (+ is East, - is West) 32
6Height 8double meters with respect to MSL 40
7Undulation 8double meters 48
8Datum ID 4integer 56
9StdDev of latitude 8double meters 60
10 StdDev of longitude 8double meters 68
11 StdDev of height 8double meters 76
12 Solution status 4integer 84