ABSTRACT
This chapter focuses on circuits containing transmission lines which have as their fundamental propagating mode the Transverse Electromagnetic (TEM) wave; that is, the electric (E) and magnetic (H) field vectors are normal to each other and to the direction of propagation, z. A TEM transmission line is a waveguide which generally consists of two metallic conductors without resistive loss extending in a longitudinally uniform geometry, example, parallel wire line, strip line, coaxial line. Multiple conductor (more than two) lines also exhibit TEM modes. The fundamental mode on a TEM line propagates down to d.c. and is called a transverse wave since both E and H field vectors lie in a transverse plane perpendicular to the guiding conductors. An important group of distributed parameter components such as filters, wideband transformers, and couplers, can be realized using stepped transmission line two-ports connected at input and output to TEM transmission lines, corresponding to resistive terminations.
