Konsberg AIS 200, Installation Manual

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Kongsberg AIS 200 Installation Manual, rev. 2 Appendix B - Digital interface IEC 61162-1
acknowledgement from the addressed "destination" AIS. The default time between retries is
s. Retries will not be attempted more frequently than 4 s. Retries stop when the appropriate
acknowledgement (See ITU-R M.1371 messages 7 and 13.) is received. The AIS will m
up to 4 bro 4
ake
adcasts, original broadcast plus three retires. This process could take 32 s to
also
f
eturn an ABK-sentence
with an acknowledgement of "2" – message could not be broadcast.
complete.
The success or failure of the reception of this broadcast by the intended AIS unit is confirmed
through the use of the "Addressed and binary Broadcast Acknowledgement (ABK)" sentence
formatter, and the processes that support the generation of an ABK-sentence. The AIS is
limited in the amount of encapsulated data that can be sent in each slot and frame. If the
length of the message would exceed five slots, or the AIS broadcast would exceed the limit o
20 RATDMA slot transmissions for the current frame, the AIS will r
NOTE 1 to the
ce
s may use null fields for fields that have not changed,
such as fields 4, 5, and 6.
NOTE 2
ence
rovided by the destination AIS unit. (See the ABK-sentence
formatter.)
OTE 3 The MMSI of the AIS unit which is the destination of the message.
NOTE 4
=
he message – one copy sent on channel A and another
copy sent on channel B.
The total number of sentences required to transfer the binary message data
AIS unit. The first field specifies the total number of sentences used for a
message, minimum value 1. The second field identifies the order of this senten
in the message, minimum value 1. All sentences contain the same number of
fields. Successive sentence
This sequential message identifier serves two purposes. It is both an IEC 61162-1
"sequential message identifier field," and it is the "sequence number" utilised by
the ITU-R M.1371 in message types 6 and 12. The range of this field is restricted
by ITU-R M.1371 to the range of 0 to 3. This sequential message identifier and
the destination MMSI uniquely identifies a message. The sequential message
identifier may be reused after the "ABK" acknowledgement for that sequ
number is p
N
The AIS channel that shall be used for the broadcast: 0 = no broadcast channel
preference, 1 = Broadcast on AIS channel A, 2 = Broadcast on AIS channel B, 3
Broadcast two copies of t
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