AN/ARC-200 nap-of-Earth HF communications systems and helicopter antenna considerations

Modern HF (2- to 30-MHz) equipment employed by today's communicator contains many technological applications and breakthroughs relative to communications equipment of the past. Today's HF communications equipment has many of the characteristics that reflect the dynamic commercial computer industry. The new HF radio used in airborne operational environments, AN/ARC-220, contains many of these technologies applied to the HF near vertical incidence skywave (NVIS) communications network. This paper discusses the considerations necessary for a properly developed network infrastructure for maximum ARC-220 mission performance. This paper also describes the HF propagation characteristics and antenna considerations encountered in typical NVIS missions using the ARC-220, especially in nap-of-earth (very close to ground) flight operations. Available lessons learned and performance characteristics are reviewed.