Automatic Link Establishment - ALE - option
ALE system overview
Operation overview
The Barrett Automatic Link Establishment (ALE) controller option simplifies the operation of
HF networks, the ALE option automating many of the procedures necessary to establish
and maintain an HF link.
The Barrett ALE controller option provides complete inter-operability as required by FED-
STD-1045 and U.S. MIL-STD-188-141A standards. The option is installed internally within a
Barrett 950 transceiver.
HF network stations equipped with ALE controllers automatically scan a preselected set of
channels, listening for ALE calls. If sounding is selected stations at random send out
“sounding calls” to other stations. These signals are analysed for link quality and stored in
the “sounded” stations. All stations gradually build up a table of parameters which
determines best channels to use to link between specific stations. These tables are used by
the a ALE controller to determine the best channel to connect on when commanded by its
operator to communicate with another station.
The Barrett ALE controller’s powerful memory stores up to 10,000 sets of LQA information,
100 channel configurations, 20 self-address configurations and 100 other address
configurations.
The ALE network parameters are determined by a network supervisor, this person programs
all the transceivers in the network with the required addressing and channel information
using the ALE fill program. This is a PC based program used to transfer pre-determined
network information into each transceiver. A separate manual is provided as a guide to ALE
network setup and for the operation of ALE fill program.
As ALE’s prime purpose is to automate many of the procedures necessary to establish and
maintain an HF link, it is only necessary for the operator to enter the station he wishes to call
and activate ALE call sequence as described in the following section. There is also the
facility to change some ALE parameters, this is not usually done in the field and sometimes
this section is locked out. The section titled “ALE menus” describes these functions.
BARRETT 950 HF TRANSCEIVER
PAGE 76