Current vehicle mounted antennas for HF NVIS (Near Vertical Incidence Skywave) communications suffer from size and performance limitations. More efficient deployable antennas can be used, but they are large and require a large, clear site for setup and a significant amount of deployment time. Neither of these solutions meets the Army''''s On-The-Move/zero setup time requirements for maintaining continuous communications with airborne Cavalry units. STAR-H Corporation has successfully demonstrated in its Phase I efforts a new, effective, rugged, simple to construct low-profile loop antenna concept that can be deployed on almost any kind of vehicle or as a stand-alone antenna. This antenna can be rapidly switched from NVIS mode to low angle mode for supporting both close-in nap of the earth operations and longer range beyond line of sight (BLOS) HF communications. In its Phase II effort, STAR-H Corporation proposes to adapt its low-profile loop antenna to two Army platforms, the HMMWV and the TOC Shelter mounted on a HMMWV. At the end of Phase II, two rugged prototype antennas, one for each platform, will be tested and delivered to the Army.The new antenna will provide NVIS HF communication between vehicles, aircraft, and ground facilities in mountainous terrain. It will also be capable of being switched to low angle propagation, which will provide enhanced long distance communication. Non-military applications will include communication among forest firefighters in mountainous terrain, plus use in emergency vehicles, oil and gas exploration, disaster relief, and communications in developing countries in similarly difficult terrain. This antenna has both a more effective NVIS radiation characteristic than alternative vehicle mounted antennas and a lower profile, reducing visibility and the risk of contact with overhead obstacles such as power lines. The market for this antenna is worldwide.
Keywords: antenna, nvis, hf, high frequency radio, skywave, propagation, modeling, low profile
