Control Theoretic Formulation of Capacity of Dynamic Electro Magnetic   Channels
  In this paper nonhomogeneous deterministic and stochastic Maxwell equations are used to rigorously formulate the capacity of electromagnetic channels such as wave guides (cavities, coaxial cables etc). Both distributed, but localized, and Dirichlet boundary data are considered as the potential input sources. We prove the existence of a source measure, satisfying certain second order constraints (equivalent to power constraints), at which the channel capacity is attained. Further, necessary and sufficient conditions for optimality are presented. 
N.U.Ahmed, F. Rezaei and S. Loyka