Design, simulation, and operation of an instrumented HF digital network for USAF´s Air Mobility Command

The USAF Air Mobility Command (AMC) has been developing an Information Processing System (IPS), with associated communications, for worldwide command and control of Air Force deliveries. The IPS must quickly process, coordinate, and send information about transport flights to fixed air bases and "contingency bases" (usually in foreign countries) set up to handle flights to areas of conflict or emergency. The messages, of various lengths and priorities, have one or more recipients, and copies are usually sent to one or more nodes besides the primary recipient. The main performance requirement of the IPS communications system (which uses several media) is the rapid delivery of error-free messages. For IPS communications over high frequency (HF) radio, this is accomplished with an automatic repeat request (ARQ) protocol, aided by powerful error-correction and signal-processing firmware in an HF data modem, which is described. Also described in detail is the Mitre data acquisition system for monitoring the network