This book is devoted to an entirely new direction of the magnetoelectronics of millimetric waves in layered structures containing epitaxial ferrite films. The new electrodynamic approach for research of electromagnetic waves in layered bigyrotropic structures- excitation of waves in converters with parallel and orthogonal orientations- is evaluated. In addition, the results of experimental research are mentioned and new methods of not destroying diagnostics of ferrite films magnetic parameters are considered. The discrepancy of resonant frequencies and the magnetic fields corresponding to them, determined from magnetoscopia and electrodynamic theories, is shown. Results of research on parameters of passive devices on milliwatt and kilowatt levels of capacity on millimetric are also explained in this text.