Modeling of electromagnetic fields in rectangular waveguides by coupled finite–infinite elements Original Research Article

The paper describes the 3D infinite element for modeling of stationary harmonic electromagnetic fields in waveguides. The proposed approximation is a straightforward modification of the analogous approach developed for analysis of scattering problems in unbounded 2D and 3D domains [Comp. Meth. Appl. Mech. Engrg. 188 (2000) 625; Int. J. Num. Meth. Engrg. 57 (2003) 899]. Exponential shape functions in the longitudinal direction are used similarly as in [Comp. Meth. Appl. Mech. Engrg. 140 (1997) 221]. However, arbitrary order of approximation in the tangential direction may be selected due to compatibility with the hp-adaptive edge FE element discretization for Maxwell’s equations in bounded domains reported in [Comp. Meth. Appl. Mech. Engrg. 152 (1998) 103; Int. J. Num. Meth. Engrg. 53 (2002) 147; Comp. Meth. Appl. Mech. Engrg. 169 (1999) 331].