To create a model of a communication system, mathematical descriptions of the transmitter, the receiver, and the effect that the environment has on the transmitted signal must be determined. Once the mathematical descriptions of these components are combined, then the model can be used to evaluate the performance of a theoretical system without the necessity of constructing it in hardware before evaluation. The final model may be in the form of equations, but due to the complexity of the environment is more likely to be incorporated into a computer simulation that combines a simplified description of the environment with the equations governing the propagation of the transmitted wave in the presence of simple structures.
This chapter outlines the elements of polarized electromagnetic radiation, and the effects of a dielectric surface or slab within the medium. The resulting sets of equations provide a simplified description of the environment which can be used in a computer simulation to compare results obtained from the model with those obtained in practical measurements. A description of the basic elements of a ray tracing algorithm are presented, as is a more detailed description of the ray tracing process. Further details of the software may be found in Appendix B.