IEC 62320 3 Edition 1 0 201 5 01 INTERNATIONAL STANDARD Maritime navigation and radiocommunication equipment and systems – Automatic identification system (AIS) – Part 3 Repeater stations – Minimum op[.]
General
All configuration sentences can be queried Queries may generate more than one response, for example EPV See Table 1 2
The Table A 1 and Table A 2 define the EPV property identifiers and value ranges
Property identifi er Property m eaning Value rang e
201 User I D The I D shall be as defined in 4 4 1
202 Primary position source 0 = I nternal GNSS
Resol ution: 1 /1 0 000 min Degrees, m inutes and fractional m inutes, E/W Format dddmm mmmm h
Resol ution: 1 /1 0 000 min Degrees, minutes and fractional minutes, N/S Format ddmm.mmmmh
2 = I TDMA/RATDMA (RATDMA when interval
3 = SOTDMA (onl y if interval ≤ 1 min)
2 9 as defined by the manufacturer (optional)
0 – 2088 Channel number according to I TU-R M 1 084-4 The channel number “0” disabl es the transmission
0 – 2088 Channel number according to I TU-R M 1 084-4 The channel number “0” disabl es the transmission
21 2 1 28 bit AES encryption key Hex form at (default all zeros)
Property identifi er Property m eaning Value rang e
0 = Repeater disabl ed, no repetition of message (default)
21 4 RATDMA enabl e 0 = RATDMA disable (default)
21 5 Maximum num ber of repetition slots Default: 50
Maximum: 400 for Type 1 , 50 for Type 2
1 = default = each message is repeated, no down sam pling
2 = every second message is repeated
3 = every 3 rd message is repeated
1 5 = every 1 5 th m essage is repeated
Fixed interval, num ber of slots
0 = default = no fi xed interval
Fixed interval, num ber of slots
0 = default = no fi xed interval
221 Repetition of AI S-SART test messages 0 = disabled (default)
PI sentences for repeater stations
RFS – Repeater station FATDMA slots
The repeater station is assigned specific slot allocations that are either reserved or restricted for its use, each identified by a record index and a valid channel designation When a query is received, the repeater station responds with multiple RFS sentences detailing all the FATDMA reserved slots.
If there are 20 responses with 10 allocated for each channel, and no slot allocation is stored, the system will output one RFS sentence with the status flag marked as “R,” while all other fields will remain null.
1 ) The record index is used to i dentify the desired RFS record, together with the AI S channel field
2) The AI S channel that the FATDMA reservation i nformation is to be applied to The character “A” indicates channel A and “B” indicate channel B This cannot be a null field when sent to the repeater station When recei ved from a repeater station, this field m ay be null, indicating that no FATDMA slots have been reserved on either channel A or channel B The channel identifies together with the record i ndex a set of slot allocati ons
3) This field identifies the ownership of the reservation Possible values are as foll ows:
L = Local ownership The repeater station recei ving this sentence owns and may utilize these FATDMA slots;
R = Remote ownershi p A repeater station receiving this sentence may not use these FATDMA slots
The command "C" indicates to the repeater station to clear the reservation from its configuration When this field is set to "C," the subsequent four fields must be set to null and will be disregarded if they contain any other values.
4) Starting slot ranging from 0 to 2 249 A null field indicates no change to the staring slot for this FATDMA reservation When recei ved from a repeater stati on, a nul l fiel d indicates that the start slot has not been set, i e is unavail abl e, when the RFS sentence is received from the AI S equipment
5) The number ranging from 1 to 5 of consecutive slots reserved for FATDMA slots A nul l field indicates no change to the number of consecutive slots reserved when sent to the repeater station, and indicates that the number of consecutive slots has not been set, i e is unavail able, when the RFS sentence is received from the repeater station
6) Slot increm ent rangi ng from 0 to 1 1 25 in slots A value of 0 i ndicates only one reservation in the frame A null field indicates no change to the current slot increment setting when sent to the AI S equipment, and indicates that the slot increm ent has not been set, i e is unavailable, when the RFS sentence is received from the AI S equi pm ent When the increment is not “0” the foll owing form ula shall appl y: 2250 mod increment = 0
7) This field is used to indicate a sentence that is a status report of current settings or a configuration command changi ng settings This fiel d shall not be null R = Sentence is a status report of current setti ngs (use for a repl y to a query) C = Sentence is a confi guration command to change setti ngs A sentence without “C” is not a command
Sentence status flag 7) Increment for reservation 6) Number of slots for reservation 5) Start slot for reservation 4) Ownership for reservation 3)
RMF – Repeater station MMSI filter
The repeater station must support at least two sets of MMSI, allowing for the inclusion or exclusion of a specified range of MMSIs Each set defines whether the MMSI range is inclusive or exclusive.
2) 0 = No MMSI filtering i n response to a query or del ete filter when sent as a com mand
3) Used to define a range of MMSI I f the first MMSI is equal to the last MMSI then only one MMSI is filtered
4) This field is used to indicate a sentence that is a status report of current settings or a configuration command changi ng settings This fiel d shall not be null R = Sentence is a status report of current settings (use for a repl y to a query) C = Sentence is a configuration comm and to change settings A sentence without “C” is not a command.
Area configuration
This group of sentences are used to configure a repeater area I t is not required to send all four sentences when configuring an area The repeater station shall support a minimum of
8 and a maximum of 1 6 of these repeater area definitions
A.2.3.2 RA1 – Repeater area part 1 configuration, basic definition
The RA1 sentence defines the area and various filters including SOG, COG, and stationary vessel A query for the RA1 will return one sentence for each area defined
Sentence status flag 4) Last MMSI 3)
First MMSI 3) MMSI filter control 2) MMSI set index 1 )
2) 0 = No area filtering in response to a query or delete area when sent as a com mand
3) The resoluti on of the latitude and longitude fiel ds shall be fixed at 1 decimal place of minutes (1 /1 0 of a minute) I f a higher resol ution is provi ded to an AI S unit, the receiving AI S unit shall truncate to 1 /1 0 of a minute
4) Maxim um number of repeats
1 = Rx messages with RI = 0 are repeated
2 = Rx messages with RI = 0 and 1 are repeated
3 = Rx messages with RI = 0 2 are repeated
5) Definiti on how the RI of the repeated message is set depending on the RI of the received message
0 = RI is incremented by 1 , maximum 3
1 = RI is set to 1 (if Rx RI < 1 )
2 = RI is set to 2 (if Rx RI < 2)
6) Minimum SOG in knots for repeating This is a variabl e length integer val ue with no decim al place or decimal digits Onl y stations which exceed this param eter are repeated
0 = default = no SOG filtering SOG in knots, 1 to 1 02
0 = default = no COG filteri ng
1 = include, stations with COG in the range are repeated
2 = excl ude, station with COG i n the range are not repeated
8) COG in degrees, 0 to 360 This is a variable length i nteger val ue with no decimal place or decimal digits
1 = Stationary vessel filtering enabl ed
$xxRA1 ,x.x,x,llll.ll,a,yyyyy.yy,a,llll.ll,a,yyyyy yy, a,x,x,x.x,x,x.x,x.x,x,a*hh
NE corner Latitude 3) Include/exclude 2) Area identification 1 )
End COG 8) Start COG 8) COG filter control 7)
SOG filter 6) Repeat indicator increment 5) Maximum number of repeats 4)
Sentence status flag 1 0) Stationary vessel filtering 9)
This field indicates whether a sentence serves as a status report of current settings or as a configuration command for changing settings It is essential that this field is not null An "R" signifies that the sentence is a status report in response to a query, while a "C" denotes a configuration command intended to modify settings Any sentence lacking a "C" is not considered a command.
A.2.3.3 RA2 – Repeater area part 2 configuration, message type filtering
The RA2 sentence defines the message type filtering A query for the RA2 will return one sentence for each area defined
The article discusses various VDL messages, highlighting their status and significance Key messages include VDL Message 1, which appears multiple times with different identifiers, indicating its importance Other notable messages are VDL Message 2, 3, 5, 6, 7, 8, 21, 24, 25, and 26, each assigned a specific status Additionally, the content addresses message ID control and area identification, emphasizing their roles in the overall communication framework.
A.2.3.4 RA3 – Repeater Area Part 3 Configuration, navigation status filtering
The RA3 sentence defines the navigation status type filtering A query for the RA3 will return one sentence for each area defined
3) 0 = Exclude navigation status identifier is not repeated
1 = I nclude, navigation status identifi er is repeated
4) This field is used to indicate a sentence that is a status report of current settings or a configuration command changi ng setti ngs This fiel d shall not be null R = Sentence is a status report of current settings (use for a repl y to a query) C = Sentence is a configuration comm and to change settings A sentence without “C” is not a command
NavStatus 1 4 3) NavStatus 1 3 3) NavStatus 1 2 3) NavStatus 1 1 3) NavStatus 1 0 3) NavStatus 9 3) NavStatus 8 3) NavStatus 7 3) NavStatus 6 3) NavStatus 5 3) NavStatus 4 3) NavStatus 3 3) NavStatus 2 3) NavStatus 1 3) NavStatus 0 3) NavStatus control 2) Area identification 1 )
A.2.3.5 RA4 – Repeater area part 4 configuration, ship and cargo type filtering
The RA4 sentence defines the ship and cargo type filtering A query for the RA4 will return one sentence for each combination of area and applied ship and cargo type
2) 0 = No shi p and cargo type filteri ng
1 = Ship and cargo type filtering enabled, all types are repeated by default
2 = Ship and cargo type filtering enabled, all types are filtered by default
3) 0 = Remove all ship and cargo types
1 = Add shi p and cargo type
2 = Remove specified ship and cargo type
4) Ship and cargo type as define by VDL Message 5
5) This field is used to indicate a sentence that is a status report of current settings or a configuration command changi ng settings This fiel d shall not be null R = Sentence is a status report of current settings (use for a repl y to a query) C = Sentence is a confi guration command to change settings A sentence without “C” is not a command.
Configuration via VDL using Message 26
The repeater station configuration over the VDL utilizes VDL Message 26 with an application identifier of 995 The fundamental structure of Message 26 is detailed in Table A.3, while the repeater command IDs are listed in Table A.4.
Sentence status flag 5) Ship and cargo type 4) Record index control 3) Ship and cargo filter control 2) Area identification index 1 )
Table A.3 – Basic structure of M essage 26
Parameter Number of bits Description Encryption status
Message I D 6 I dentifi er for Message 26 Unencrypted
Repeat indicator 2 Used by the repeater to indicate how m any times a message has been repeated 0 = default; 3 = do not repeat any more
Source I D 30 MMSI for the source station Unencrypted
I ndicator 1 Always 1 for addressed message Unencrypted
Binary data flag 1 Always 1 for structured data Unencrypted
Destinati on I D 30 The MMSI of the repeater station to which the comm and is addressed Unencrypted
Spare bits 2 Used for byte ali gnment Unencrypted
Application identifi er 1 6 DAC shall al ways be 995 for repeater
FI = 1 = Repeater configurati on command
FI = 2 = Repeater configurati on response
Binary Data 1 28 to 896 Encrypted binary data in 1 28 bit blocks Encrypted
Spare bits 4 Used for byte ali gnment
Communication state selector flag 1 0 = SOTDMA comm unication state follows 1 = I TDMA communication state foll ows Unencrypted
Communication state 1 9 SOTDMA com munication state if communication state selector flag is set to 0, or I TDMA communication state if communication state selector fl ag is set to 1
Table A.4 – Message 26 repeater command IDs
Table A 5 to Table A.21 describe the structure of the Message 26 for the various command IDs The shaded areas indicate how the binary data block of Table A.3 is used
Parameter Number of bits Description Encryption status
Message I D 6 I dentifi er for Message 26 Unencrypted
Repeat indicator 2 Used by the repeater station to indicate how many times a message has been repeated 0 = default; 3 = do not repeat any more
Source I D 30 MMSI for the source station Unencrypted
I ndicator 1 Always 1 for addressed m essage Unencrypted
Binary data flag 1 Always 1 for structured data Unencrypted
Destinati on I D 30 The MMSI of the repeater station to which the comm and is addressed
Spare bits 2 Used for byte ali gnment
Application identifi er 1 6 DAC shall al ways be 995 for repeater
FI = 1 = Repeater configurati on command
FI = 2 = Repeater configurati on response
Command I D 8 1 = EPV configuration comm and Encrypted
Property identifier 8 201 to 221 (excluding AES encryption key) Encrypted
Payload 32 Value is dependent on the EPV property identifier U nused bits are set to 0 Encrypted
Spare bits 72 Required for 1 28 bit block boundary Encypted
Checksum 8 Used to vali date the decryption Encrypted
Spare bits 4 Used for byte ali gnment
Communication state selector flag 1 0 = SOTDMA comm unication state follows 1 = I TDMA communication state foll ows Unencrypted
Communication state 1 9 SOTDMA com munication state if communication state selector flag is set to 0, or I TDMA communication state if communication state selector fl ag is set to 1
Parameter Number of bits Description Encryption status
Message I D 6 I dentifi er for Message 26 Unencrypted
Repeat indicator 2 Used by the repeater station to indicate how many times a message has been repeated 0 = default; 3 = do not repeat any more
Source I D 30 MMSI for the source station Unencrypted
Destinati on indicator 1 Always 1 for addressed m essage Unencrypted
Binary data flag 1 Always 1 for structured data Unencrypted
Destinati on I D 30 The MMSI of the repeater station to which the comm and is addressed
Spare bits 2 Used for byte ali gnment
Application identifi er 1 6 DAC shall al ways be 995 for repeater
FI = 1 = Repeater configurati on command Command I D 8 2 = EPV query Returns the desired property identifier Encrypted Property identifier 8 201 to 221 (excluding AES encryption key) Encrypted
Spare bits 1 04 Required for 1 28 bit block boundary Encrypted
Checksum 8 Used to vali date the decryption Encrypted
Spare bits 4 Used for byte ali gnment
Communication state selector flag 1 0 = SOTDMA comm unication state follows 1 = I TDMA communication state foll ows Unencrypted
Communication state 1 9 SOTDMA com munication state if communication state selector flag is set to 0, or I TDMA communication state if communication state selector fl ag is set to 1
Table A.7 – Property identifiers for use with EPV – Basic system parameters
Property identifi er Property m eaning Bits a Description
201 User I D 30 The I D shall be as defined in 4 1 1
202 Prim ary position source 1 0 = I nternal GNSS
203 Repeater station’s Longitude 28 Longitude in 1 /1 0 000 min ( ± 1 80º, East = positi ve (as per 2’s complement), West = negative (as per 2’s complement);
1 81 = (6791 AC0h) = not avail able = default)
204 Repeater station’s Latitude 27 Latitude in 1 /1 0 000 min ( ± 90º, North = positi ve (as per
2’s complement), South = negative (as per 2’s com plement);
3 = SOTDMA (onl y if interval