Transas T214, Technical Manual

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Settings of Base Station configuration
Chapter 6. Commissioning.Internal configuration
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sentence is received from the AIS equipment. (ref. version of ITU-R M.1371-1
available on ITU WEB site).
2. Starting slot ranging from -1 to 2249 for ITU-R M.1371 messages 17, 20 or 22,
broadcasts on Channels “A” or “B”. A value of –1 discontinues broadcasts of the
message when the CBM sentence is sent to the AIS equipment, and indicates
that no message has been broadcast if the CBM sentence is received from the
AIS equipment. A null field indicates no change to the current start slot setting
when sent to the AIS equipment, and indicates that the start slot has not been
set, i.e. is unavailable, when the CBM sentence is received from the AIS
equipment.
3. Slot Interval ranging from 75 to 1125 in slots, between broadcasts of ITU-R
M.1371 messages 17, 20 or 22 on Channels “A” or “B”. A value of 0 indicates
only one broadcast is scheduled in the frame. A null field indicates no change to
the current slot interval setting when sent to the AIS equipment, and indicates
that the slot interval has not been set, i.e. is unavailable, when the CBM
sentence is received from the AIS equipment. It should be noted that three slots
for each GNSS system should be reserved for corrections. Caution should be
taken for message 17 when defining the increment to ensure that both
corrections and integrity warnings are considered.
4. For messages other than message 17, this field is null. For message 17 the
number may range from 1 to 4 consecutive slots. A maximum of 3 slots is
recommended for each DGNSS service. A null field indicates no change to the
number of consecutive slots reserved when sent to the Base Station, and
indicates that the number of consecutive slots has not been set, i.e. is
unavailable, when the ECB sentence is received from the Base Station.
ЕСВ – Configure Broadcast Rates for Base Station Messages with
Epoch planning support
This sentence is setup in the Configuration->Setup->BS setup->Schedule
(CBM/ECB) menu. The value of the Configuration->Setup->BS setup->Epoch
planning mode parameter should correspond to the “On” value.
This sentence assigns the schedule of slots that will be used to broadcast the
specified message – 4, 17, 20, 22, and 23. It provides the start slot and interval
between the slots used for consecutive transmissions for the message. The interval
span supports creation of broadcast schedules base upon a 6 minute FATDMA
epoch. The AIS Base Station should apply the information provided by this sentence
to autonomously and continuously transmit the VDL message indicated until revised
by a new ECB sentence.