Contents
EMAP4 is a three-dimensional edge based finite element code that uses complex numbers to represent the electric field values. EMAP4 can analyze a wide variety of structures, ranging from waveguides and transmission lines to cavities. EMAP4 can be applied to solve both non-open region and open-region problems (by the use of PMLs) as seen from the examples in Section 6 and 7. The code uses the Complex Biconjugate Gradient (CBCG) method (Section 8), which makes it relatively efficient compared to earlier versions of the EMAP codes. Non-uniform meshes can also be used with EMAP4.
There are a few areas in which future development of this code is necessary. The matrix solver uses more than 95% of the total running time (even with the CBCG routine). New, more efficient, matrix solving routines must be implemented to solve real problems in a reasonable time. The mesh generation used in this code is very primitive. This does not work well if there is a large variation in the structure complexity; for example, if there are thin wires in a large cavity. The code would be much more useful if it had a better mesh generator or an interface to a commercial mesh generator. The code also needs to model sources and feeds; for example, coaxial feeds and wire sources in a better manner (either by generating a good mesh or by using other techniques).
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