Efficient Numerical Techniques for Analyzing Microstrip Circuits and Antennas Etched on Layered Media via the Characteristic Basis Function Method

Abstract

The first part of this chapter presents an efficient technique for the electromagnetic analysis of planar microstrip structures, called the Characteristic Basis Function Method (CBFM). In this method, the original problem geometry is segmented into smaller regions called blocks, and high-level basis functions are generated to represent the electromagnetic characteristics of these sections. These basis functions are referred to as the Characteristic Basis Functions (CBFs), and their use leads to a reduced matrix equation system. Since the method only requires the solution a relatively of small-size matrix equations, associated with isolated domains, the computational burden is relieved, and an acceleration of the solve time is achieved. In the second part of the chapter, the Characteristic Basis Function Method is combined with the Equivalent Medium Approach (EMA) for fast and efficient design of microstrip circuits etched on layered media. In particular, the developed EMA method substitutes the stratified environment with an equivalent “homogeneous” medium whose Dyadic Green’s Functions (DGF’s) can be evaluated analytically. The above technique yields reliable results and reduces the computational time in comparison with the conventional Method of Moments (MoM). Some examples that demonstrate the accuracy and the efficiency of the described procedures are included.