Conformal mapping analysis of a modified TEM cell

A modification procedure in which the inner conductor of the usual TEM cell is symmetrically finned with a pair of small vertical plates is proposed to obtain a more suitable uniform field. In such modified TEM cells, a fairly uniform field can be established just above the inner surface of the rectangular-shaped shield instead of in the central portion of the separation between the septum and the shield, and this uniform field can be used for EMC measurements without dielectric equipment support or on a ground screen. The usefulness of the proposed modification is illustrated by the conformal mapping analysis of a special modified TEM cell. A similar modification can also be made in a general TEM cell and GTEM cell for the aforementioned uses. Conclusions and discussions are given, and further work is suggested