Guidelines : AIS Message 1,2,3

NMEA Format

Parameter	Number of bits	Description
Message ID	6	Identifier for this message 1, 2 or 3
Repeat indicator	2	Used by the repeater to indicate how many times a message has been repeated. Refer to § 4.6.1; 0-3; 0 = default; 3 = do not repeat any more
User ID	30	MMSI number
Navigational status	4	0 = under way using engine, 1 = at anchor, 2 = not under command, 3 = restricted manoeuvrability, 4 = constrained by her draught, 5 = moored, 6 = aground, 7 = engaged in fishing, 8 = under way sailing, 9 = reserved for future amendment of navigational status for ships carrying DG, HS, or MP, or IMO hazard or pollutant category C (HSC), 10 = reserved for future amendment of navigational status for ships carrying DG, HS or MP, or IMO hazard or pollutant category A (WIG); 11-14 = reserved for future use, 15 = not defined = default
Rate of turn ROTAIS	8	±127 (–128 (80h) indicates not available, which should be the default). Coded by ROTAIS = 4.733 SQRT(ROTINDICATED) degrees/min ROTINDICATED is the rate of turn (720°/min), as indicated by an external sensor. +127 = turning right at 720°/min or higher –127 = turning left at 720°/min or higher
SOG	10	Speed over ground in 1/10 knot steps (0-102.2 knots) 1 023 = not available, 1 022 = 102.2 knots or higher
Position accuracy	1	1 = high (< 10 m; differential mode of e.g. DGNSS receiver) 0 = low (> 10 m; autonomous mode of e.g. global navigation satellite system (GNSS) receiver or of other electronic position fixing device); 0 = default
Longitude	28	Longitude in 1/10 000 min (±180°, East = positive, West = negative. 181° (6791AC0h) = not available = default)
Latitude	27	Latitude in 1/10 000 min (±90°, North = positive, South = negative. 91° (3412140h) = not available = default)
COG	12	Course over ground in 1/10° (0-3599). 3600 (E10h) = not available = default. 3 601-4 095 should not be used
True heading	9	Degrees (0-359) (511 indicates not available = default)
Time stamp	6	UTC second when the report was generated (0-59 or 60 if time stamp is not available, which should also be the default value or 62 if electronic position fixing system operates in estimated (dead reckoning) mode or 61 if positioning system is in manual input mode or 63 if the positioning system is inoperative)
Reserved for regional applications	4	Reserved for definition by a competent regional authority. Should be set to zero, if not used for any regional application. Regional applications should not use zero
Spare	1	Not used. Should be set to zero
RAIM-flag	1	RAIM (Receiver autonomous integrity monitoring) flag of electronic position fixing device; 0 = RAIM not in use = default; 1 = RAIM in use
Communication state	19	See below
Total number of bits	168

CISE Format

<?xml version="1.0" encoding="UTF-8"?>
<!-- mapping of AIS message 1,2,3 - the comments indicate the field used from AIS and the way it is encoded in AIS - missing elements: ROT??-->
<Vessel xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="https://cise.jrc.ec.europa.eu/datamodel/last/xsd/Vessel.xsd">
	<LocationRel>
		<Location>
			<Geometry>
				<Latitude>37.9333</Latitude><!--Latitude, in 1/10 000 min, north=positive, south=negative -->
				<Longitude>23.5301</Longitude><!--Longitude, in 1/10 000 min, east=positive, west=negative -->
			</Geometry>
			<LocationQualitativeAccuracy>High</LocationQualitativeAccuracy><!--code list in AIS: 1=high, 0=low-->
		</Location>
		<COG>12</COG><!-- COG: in 1/10 of degree -->
		<Heading>9</Heading><!-- True Heading: in degree -->
		<PeriodOfTime>
			<StartDate>2016-12-21</StartDate><!-- Time Stamp -->
			<StartTime>23:59:00Z</StartTime><!-- Time Stamp -->
		</PeriodOfTime>
		<SourceType>Declaration</SourceType>
		<SensorType>AutomaticIdentificationSystem</SensorType>
		<SOG>90.2</SOG><!-- SOG, in 1/10 of knots -->
	</LocationRel>
	<MMSI>123456789</MMSI><!-- User ID -->
	<NavigationalStatus>UnderWayUsingEngine</NavigationalStatus><!-- Navigational Status, code list: 0 to 15 -->
</Vessel>

Detailed Mapping

CISE data model element	AIS message type	AIS element	formating or code conversion		Remarks
CISE data model element	AIS message type	AIS element	AIS	CISE	Remarks
Vessel.LocationRel.Location.Geometry.Latitude	1,2,3	Latitude	in 1/10 000 min, north=positive, south=negative Position of the GPS antenna	in degree, north=positive, south=negative Position of the middle of the ship	(CISE documentation to be fixed) For accurate position, a conversion of the position from the GPS position to the middle of the ship needs to be done, taking into account the position of the GPS on the ship ("dimension" parameter of Message 5) and the True Heading (in this message)
Vessel.LocationRel.Location.Geometry.Longitude	1,2,3	Longitude	in 1/10 000 min, east=positive, west=negative Position of the GPS antenna	in degree, east=positive, west=negative Position of the middle of the ship	Same remarks as above
Vessel.LocationRel.LocationQualitativeAccuracy	1,2,3	Position accuracy	1 = high 0 = default	High Medium
Vessel.LocationRel.COG	1,2,3	COG	in 1/10° (0-3599). 3600 (E10h) = not available = default	in degree if not available, no value
Vessel.LocationRel.Heading	1,2,3	True heading	Degrees (0-359) 511 indicates not available = default	in degree if not available, no value
Vessel.LocationRel.PeriodOfTime.StartDate	1,2,3	Time stamp	UTC second when the report was generated (0-59 or 60 if time stamp is not available, which should also be the default value or 62 if electronic position fixing system operates in estimated (dead reckoning) mode or 61 if positioning system is in manual input mode or 63 if the positioning system is inoperative)	formated as YYYY-MM-DD	requires to add the time stamp to the actual time/date and extract the date.
Vessel.LocationRel.PeriodOfTime.StartTime	1,2,3	Time stamp	UTC second when the report was generated	formated as hh:mm:ss	requires to add the time stamp to the actual time/date and extract the time.
Vessel.LocationRel.SourceType	-	-	-	fixed value in the case of AIS: Declaration
Vessel.LocationRel.SensorType	-	-	-	fixed value in the case of AIS: AutomaticIdentificationSystem
Vessel.LocationRel.SOG	1,2,3	SOG	Speed over ground in 1/10 knot steps (0-102.2 knots) 1 023 = not available, 1 022 = 102.2 knots or higher	in knots if not available, no value
Vessel.MMSI	1,2,3	User ID	MMSI Number	same as AIS
Vessel.NavigationalStatus	1,2,3	Navigational status	0 = under way using engine, 1 = at anchor, 2 = not under command, 3 = restricted manoeuvrability, 4 = constrained by her draught, 5 = moored, 6 = aground, 7 = engaged in fishing, 8 = under way sailing, 9 = reserved for future amendment of navigational status for ships carrying DG, HS, or MP, or IMO hazard or pollutant category C (HSC), 10 = reserved for future amendment of navigational status for ships carrying DG, HS or MP, or IMO hazard or pollutant category A (WIG); 11-14 = reserved for future use, 15 = not defined = default	UnderWayUsingEngine AtAnchor NotUnderCommand RestrictedManoeuvrability ConstrainedByHerDraught Moored Aground EngagedInFishing UnderWaySailing Other Other Other UndefinedDefault
(not yet supported)	1,2,3	Rate of turn ROTAIS		-	this could be added to the CISE model