User's Manual

R60 Station
R60 User Manual
Document Number
Version
Date
7000 120-019
A1
2022-08-10
Page 69 (98)
6.14 Configure > Repeater (Full Base Station only)
The R60 supports AIS repeater functionality in accordance with IEC 62320-3, Ref [7].
The standard defines how an AIS repeater shall work and defines many functionalities
intended to avoid overloading the VDL and reducing the risk of misconfiguration.
Among other many different filters for what shall be repeated are defined. All this
results in a fairly complex configuration, but allows for complex repeating scenarios to
be implemented.
The Repeater category page is located in the Configure main category group. It is
divided into a number of sub-categories where settings are made, see sections 6.14.2
to 6.14.5.
6.14.1 Process used to repeat a message
For the R60 to repeat messages at all a number of conditions must be fulfilled:
 Repeater must be enabled (see General  Enable in Table 6-12).
 Repeater MMSI must defined (see General  MMSI in Table 6-12).
 Transmit of the repeater report must be setup (see Report in Table 6-12).
 Repeat must be enabled on the channel in question (see Transmit  Enable Tx
in Table 6-12).
 UTC time must be known, this means the R60 must be in UTC direct or indirect
synchronization.
The only AIS messages that can be repeated are 1, 2, 3, 5, 6, 7, 8, 12, 13, 14, 15, 18, 19,
21, 24, 25 and 26. Also timestamps cannot be older than 30 seconds (for AIS messages
which contains a timestamp).
Before a message is repeated, it must also pass all repeater filters.
First, it must pass the MMSI filters, see 6.14.4 for configuration and how the MMSI
filters work.
Then it must pass the area filters. There must be at least one include area, or nothing
will be repeated. See 6.14.5 for information on how the area filters work.
Once a message has passed the area filtering it may still be stopped from repetition
due to down-sampling. Only position reports from ships are affected by down-
sampling (message 1, 2, 3 and 18).
Down-sampling is the process of reducing the number of messages which are repeated
by only repeating every other, third, etc., position report of a vessel (see
Downsampling in Table 6-12). There is also automatic down-sampling which happens
when the maximal number of slots used for repeated messages is exceeded.
There are further checks done by the R60 before repeating, but these are
automatically handled and require no configuration. Please refer to Ref [7] for further
information.