Helicopter Propagation Effects and Countermeasures for Reliable Bandwidth Efficient Communications via Satellite

Mobile communications via satellite require an unobstructed path between the user terminal and the satellite. Terminal installations on helicopters result in poor performance because their antennas are installed below the rotating blades and the link suffers from periodic blockages caused by the signal obstruction as well as significant ripples caused by multipath signal reflections. The helicopter propagation model as well as various countermeasures is presented. With the proposed techniques high bandwidth efficiency may be achievable to/from helicopters and at the same time the reliability of the link and service area increases.