Transas T214, Техническое руководство

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Settings of Base Station configuration
TRANSAS AIS BASE STATION T214. Technical Manual.
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1. Each AIS Base Station shall, as a default, be identified by its own individual
MMSI. The AIS Base Station MMSI shall be configurable by means of a SID
sentence via the PI.
2. The AIS Base Station shall be capable of transmitting messages with a different
MMSI provided by the PSS by means of a standard VDM input sentence.
3. The AIS Base Station shall be able to receive all VDL messages;
4. Every received VDL message shall be passed to the PI as a VDM sentence
without further data content processing;
5. Every received PI VDM sentence shall be broadcast on the VDL beginning in
the slot indicated by the TSA sentence without further data content processing;
6. Every message transmitted on the VDL shall be passed to the PI as a VDO
sentence;
7. Messages to be broadcast on the VDL are passed using the sentence linking
method.
8. A Dependent Base Station does not transmit msg4 without PSS control. All
transmissions are done via VDM/TSA-PI Input Sentences. 62320-1 CDV-Final
9. A Dependent Base Station shall not be semaphore qualified and shall not
operate autonomously.
10. When the UTC sync source is unavailable, the AIS Base Station shall use UTC
indirect (ITU-R M.1371-1 A2, 3.1.1.2), Synchronized to base station (ITU-R
M.1371-1 A2, 3.1.1.3 ) or the semaphore rules (ITU-R M.1371-1 A2, 3.1.1.4 )
11. Upon request via the Sentence VER, the AIS Base Station shall provide its
hardware and software version information.
12. Base Station shall use the FATDMA access scheme only.
«Independent» operation
The default access scheme for a Base Station shall be FATDMA. The AIS Base
Station may use the FATDMA and RATDMA access schemes concurrently. The use
of pre-reserved FATDMA slots shall take priority over RATDMA access.
When using the FATDMA access scheme, the absolute slot numbers for
transmission shall be determined by one or both of the following methods:
The PI sentence pair VDM/TSA shall provide the absolute slot number in which the
AIS Base Station transmits; and/or
The AIS Base Station shall autonomously select an appropriate pre-reserved
FATDMA slot determined by the configuration as previously provided via the PI.
When operating as an independent Base Station, the unit shall comply with the
following general rules:
1. With regard to the access schemes to the VDL, refer to section 6.3.4 AIS Base
Station Interaction on the VDL.
2. The AIS Base Station shall, as a default, use a surveyed position. When using a
surveyed position, the “Position accuracy” flag in VDL Message 4 shall be set
upon configuration, and the “RAIM” flag shall be set to 0.
3. When the UTC sync source is unavailable, the AIS Base Station shall use UTC
indirect (ITU-R M.1371-1 A2, 3.1.2) or the semaphore rules (ITU-R M.1371-1
A2, 3.1.1.4).