Finite-element analysis of a triple-TEM cell

The triple-TEM (TTEM) cell offers the possibility of alternative exposures of the electric field on the equipment under test in one setup. Traditional TEM cell design approaches cannot be applied to the TTEM cell because of the special geometric arrangement of the inner conductors. Several important characteristics of the TTEM cell, such as TEM field distributions, characteristic impedance, and cutoff frequencies of higher order modes (TE and TM) are analyzed by using the finite-element method (FEM). The high-frequency performance of the TTEM cell is investigated using a novel FEM approach-the Laplace domain finite-element method (LDFEM). Numerical results obtained thereupon are useful in the engineering design of the TTEM cell