Implementation of a point-to-point ray tracer

Most ray tracers treat the problem as a Hamiltonian optics problem given an index of refraction, i.e., the ionosphere in this case.  However, Coleman 2011 developed a method for ray tracing that used a direct variation method.  The advantage of this method is that the endpoints of the ray remained fixed, while in more standard ray tracer, rays are launched until a link is made between the transmitter and receiver.  Development of this method may provide a potentially efficient method for determining the link between a transmitter receiver pair, given a model ionosphere.  We present efforts toward implementing the methodology described by Coleman 2011.