SRT CS100, Installation And Operation Manual

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Configuration using proAtoN
Page 25
7.4.2 Message schedule configuration
The layout of the message schedule tab is described in Figure 11.
Figure 11 proAtoN message schedule tab layout
Default messages
An AIS AtoN position report is made using AIS message #21. This message occupies two AIS slots. The
default configuration shown in proAtoN includes two message #21 schedule configurations. The first
configuration, index 1, is the primary position reporting schedule for the transceiver. The second, index 2, is
the alternate position reporting schedule selected when the ‘off position’ monitor is enabled and the AtoN is
determined to be off position (see section 7.4.1). If the alternate ‘off position’ schedule is not required it can be
deactivated by selecting the associated row in the message schedule table and clicking the ‘Deactivate’ button.
When deactivated the alternate schedule will be greyed out.
Access scheme selection
The access scheme for each message must be selected as either FATDMA or RATDMA (see section 3.2). The
selection is made by selecting the required row in the schedule table, then clicking on the current access
scheme in that row. A drop down menu will then appear in that location allowing selection of the required
access scheme.
● FATDMA
Configuration of an FATDMA schedule continues in section 7.4.3.
● RATDMA
Configuration of an RATMDA schedule continues in section 7.4.4.
7.4.3 FATDMA Schedule configuration
Using the FATDMA (Fixed Access TDMA) access scheme the actual slot for each transmission made by the
transceiver is specified. There are 2250 slots per minute (or frame) on each AIS channel. The scheduled slots
must be reserved for the transceiver by an AIS base station operating in the same area using AIS message
#20. Further information on FATDMA reservations and slot allocation schemes can be found in IALA A-124,
Appendix 14.
The parameters required for an FATDMA schedule are as follows.
Channel 1 start UTC
This is the hour and minute for transmission on channel 1. This specifies the AIS frame (minute) within a day
in which the start slot for channel 1 resides.
Add new message
schedules
Current messages
and schedules
Deactivate or remove
selected schedule