Two-dimensional analytic HF ray tracing in the ionosphere

This paper describes a method to accurately ray trace through horizontal gradients in the ionosphere that vary with altitude in the direction of the propagated ray path. In the past, tilting methods have been employed to approximate the effects of horizontal gradients where these methods involve tilting the ionosphere relative to the earth´s surface. These methods can be quite cumbersome, whereas this method is relatively simple and in general will produce more accurate results and is considerably faster, in elapsed computational time, than ionospheric tilting methods. This method can also be added to SMART (Norman and Cannon 1997).