SRT CS100, Installation And Operation Manual

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Configuration using proAtoN
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Virtual AtoN schedule
The transmission schedule for a virtual or synthetic AtoN must be configured in the same way as that for the
‘real’ AtoN. The TDMA access scheme, start times and intervals must be configured in the virtual AtoN tab
following the guidance in section 7.4.3 or 7.4.4 as appropriate. When an FATDMA schedule is used it is
important to ensure the slot allocations used for the virtual and real AtoNs are different in every case. Also note
that two consecutive slots are used for each virtual AtoN report.
7.4.6 Message repeater function
The transceiver can be configured to repeat, or re-transmit, certain messages it receives. Note: messages from
virtual AtoN’s are not repeated. This feature applies to messages #6, #8, #21 and to SART specific messages
#1 and #14. This feature is turned off by default for all message types but can be enabled and configured using
the Repeater tab. The number of messages that are repeated is limited by the number of messages waiting to
be repeated and the total number of transmissions made per UTC minute.
Figure 15 Message repeater tab layout
For each message type, the repeat function can be disabled - Off - or enabled to repeat received messages
with a Repeat Indicator (RI) value equal to or less than 0, 1 or 2. The RI value states how many times the
message has already been repeated where 0 means it was transmitted by the source.
For messages #6, #8 and #21, a Guard Time can be applied. This creates a period after a message is repeated,
during which the same message type from the source MMSI will not be repeated again, regardless of the
message's RI value. For example, if a message #6 from MMSI A is repeated then a second message #6 is
received from MMSI A within the Guard Time, the second message shall be interpreted and acted upon as
necessary but it will not be repeated; however, if a third message #6 from MMSI A is received after the Guard
Time has expired, it will be repeated so long as its RI value is less than or equal to that configured for the AtoN.
For message #21, a Range constraint can also be applied. Any message #21 that meets the other criteria for
repeating, shall be transmitted if the position reported is within the distance specified by the Range value of the
receiving AtoN. A Range value of 0 indicates the restriction is disabled.
7.5 Transceiver diagnostics
The proAtoN application provides a number of features to assist with installation of an AIS AtoN and diagnosis
of fault conditions. These features are available through the GPS, Serial Data and Diagnostics tabs in proAtoN.
Repeat message #21
Repeat message #8
Repeat message #6
Repeat SART messages
#1 and #14