Using Automatic Link Establishment (ALE)
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After a bidirectional handshake with a single station, the LQA matrices of both radios are updated.
The operator can then initiate a call to that station and obtain the best channel automatically.
When the bidirectional handshake procedure is performed with a net, all the stations in the net
update their LQA tables.
Selective Calling
MICOM-3 uses an approach standardized in MIL-STD-181-141B and FED-1075 to selective calling,
and therefore has the capability and flexibility to link with one or many prearranged or as-needed
single or multiple stations.
ALE Addressing Method
ALE uses digital addresses to identify stations. The fundamental address element in the ALE system is
the single word: one ALE address word must always contain three characters (one triplet).
A single ALE word is needed for the basic individual station address (this is called a
basic address
). To
increase the available range of addresses, basic addresses can be expanded up to a maximum of 5
words (15 characters): such addresses are called
extended addresses
.
The characters that can used in addresses are a subset of the standard Basic 38 ASCII character set.
This subset includes:
•
All the capital (upper case) letters (
A
to
Z
)
•
All the digits (
0
to
9
)
•
Two utility characters:
!"
The stuffing symbol
@
. It can be used to add characters at the end of an address, so that
the resulting length is a whole number of words (triplets). A receiving station then interprets
only the non-stuffing characters. For example, if the address has 8 characters, add one
@
at
the end of the address, whereas for an address with 7 characters, two
@
symbols must be
added. In special addressing modes, this symbol is interpreted as an
ignore
instruction: see
additional utilization guidelines in Table 1.
!"
The wildcard symbol
?
. It is used to indicate that any character (except
@
) is acceptable
(this is the equivalent of a
don’t mind
instruction). See Table 2 for utilization guidelines in
the special addressing modes.
Note
In the following sections, “A,” “B,” “C” or “D” indicates any alphanumeric
character other than “@” or “?”.
MICOM-3 has the capacity to store and use 100 addresses of up to 15 characters each. MICOM-3
will reject addresses longer than 15 characters, and will notify you with an UFA WRONG message.
Address and Call Types
ALE stations, including the MICOM-3, have the capability and flexibility to link with one or many
prearranged or as-needed single or multiple stations. There are three general addressing methods:
•
Individual station addressing
•
Multiple stations addressing, for example, net and group
•
Special addressing modes, for example, AllCall, AnyCall, etc.
The following sections explain the addressing modes and how they can be used for various purposes.
