ABSTRACT
In this chapter the mathematical methods required for obtaining asymptotic solutions for the fields are presented. These are the Watson transformations, the stationary point method, and the method of steepest descent (i.e., the saddle point method). The emphasis is on the use of these methods in the evaluation of the resulting field expressions in electromagnetic wave propagation. This results in the proper asymptotic solution, valid in the far field. Several important cases where the use of this mathematical procedures are required are shown. The classical problem of a pole near a saddle point and the resulting solution in terms of the complementary error function is discussed in detail.
