Modal propagation, energy storage and dissipation in uniform, linear, isotropic waveguides

By systematic application of Lorentz' reciprocity theorem, we have derived the general constraints linking propagation constant, power flow, dissipation and storage in a closed, uniform, waveguide loaded with linear, isotropic material. The frequency variations of the above physical quantities are constrained also, as can also be derived from the reciprocity theorem. In the particularly important case of a lossless guide, critical points in the characteristics, backward and complex waves are also discussed.