AIS Message Definitions

AIS Message: position (::)

Description:

Scheduled position report

Note:Need to make much of this an include-struct so that 1-3 are as simple as possible

See Also:

Name NumberOfBits ArrayLength Type Units Description
MessageID 6 uint AIS message number. Must be 1
RepeatIndicator 2 uint Indicated how many times a message has been repeated
0: default
3: do not repeat any more
UserID 30 uint Unique ship identification number (MMSI)
NavigationStatus 4 uint What is the vessel doing
0: under way using engine
1: at anchor
2: not under command
3: restricted maneuverability
4: constrained by her draught
5: moored
6: aground
7: engaged in fishing
8: under way sailing
9: reserved for future use (hazmat)
10: reserved for future use
11: reserved for future use
12: reserved for future use
13: reserved for future use
14: reserved for future use
15: not defined = default
ROT 8 int 4.733*sqrt(val) degrees/min Rate of turning. Positive right; negative left. BROKEN!
SOG 10 udecimal knots Speed over ground
102.2: 102.2 knots or higher
PositionAccuracy 1 uint Accuracy of positioning fixes
0: low (greater than 10 m)
1: high (less than 10 m)
longitude 28 decimal degrees Location of the vessel East West location
latitude 27 decimal degrees Location of the vessel North South location
COG 12 udecimal degrees Course over ground
TrueHeading 9 uint degrees True heading (relative to true North)
TimeStamp 6 uint seconds UTC second when the report was generated
60: not available/default
61: manual input
62: dead reckoning
63: inoperative
RegionalReserved 4 uint Reserved for definition by a regional authority.
Spare 1 uint Not used. Should be set to zero.
RAIM 1 bool Receiver autonomous integrity monitoring flag
False: not in use
True: in use
state_syncstate 2 uint Communications State - SOTDMA Sycronization state
0: UTC direct
1: UTC indirect
2: synchronized to a base station
3: synchronized to another station
state_slottimeout 3 uint frames Communications State - SOTDMA Frames remaining until a new slot is selected
0: Last frame in this slot
1: 1 frames left
2: 2 frames left
3: 3 frames left
4: 4 frames left
5: 5 frames left
6: 6 frames left
7: 7 frames left
state_slotoffset 14 uint Communications State - SOTDMA In what slot will the next transmission occur. BROKEN