Rh = horizonrange(H)
Rh = horizonrange(H,Re)
Height of radar system above surface, in meters. This argument can be a scalar or a vector.
Effective earth radius in meters. This argument must be a positive scalar.
Default: effearthradius, which is approximately 4/3 times the actual earth radius
Horizon range in meters of radar system at altitude H.
The horizon range of a radar system is the distance from the radar system to the earth along a tangent. Beyond the horizon range, the radar system detects no return from the surface through a direct path.
The value of the horizon range is:
where Re is the effective earth radius and H is the altitude of the radar system.
 Long, Maurice W. Radar Reflectivity of Land and Sea, 3rd Ed. Boston: Artech House, 2001.
 Skolnik, M. Introduction to Radar Systems, 3rd Ed. New York: McGraw-Hill, 2001.