ABSTRACT
In Chapter 2 some fundamentals of antennas were introduced in order to understand and address the problem of UWB antennas. Due to the complexity of solving analytically the electromagnetic equations related to antennas (either narrowband, wideband or ultra wideband), the present chapter is dedicated to the subject of solving them numerically, through which the reader is provided with some ideas of the background of the simulation packages used to this aim. As will be seen in Section 9.1, the essence of the electromagnetic theory formulated by James Clerk Maxwell can be outlined by a set of partial differential equations. There exist many references (including symposiums) addressing solution methods for this type of equation (see [1-5] for instance). Although it is not, of course, the aim of this chapter to present a treatise on differential equations, but to point out some particular aspects of them related to the Maxwell’s equations, Appendix B is just given as a quick reference. Finally, it is important also to note that the complexity of the topic of numerical methods usually requires a wide treatise like in [6-11] to mention just a few. In spite of the fact that only a brief exposition and the background for these methods are addressed in this chapter, they are included as a part of this book due to the relevance of the theme.
