Practical real time frequency management for automated HF networks

A frequency management system for an automatic HF network is described. MUF updates are calculated automatically with 99% reliability without the need for dedicated, specialist equipment. The process also allows disturbances to be identified and utilised if appropriate. Channel selection is achieved in such a way as to minimise interference and maximise reliability. The chosen channel is monitored throughout the passing of the message in order to allow rapid response to changing conditions. The techniques have been tested over a 132 km link with encouraging results. They are being incorporated into a network of 80 stations which will shortly be undergoing acceptance tests.<>