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Millimeter plasmas were tailored to play a role as dynamic devices of microwave components, that is, to control electromagnetic wave propagation dynamically on a microstrip line. The generation of millimeter plasmas with their relatively long discharge channel (∼3 mm) was in high-pressure (20-200 torr) Ne, and they were successfully arranged near and on the conductor of microstrip lines. When such a plasma was set perpendicularly to the conductor to form a T junction, a significant reduction of electromagnetic wave transmission along the metal conductor was observed. The reduction rate depended on the discharge current and the number of T junctions. These experimental results are compared with the case of 2 MHz launching for crude electron density measurements and the numerical results of propagating electric fields in a two-dimensional model. [ABSTRACT FROM AUTHOR]

We analyze the error in typical moment method scattering solutions for smooth cylindrical geometries and TM-polarized fields. We consider the magnetic field integral equation (MFIE), electric field integral equation (EFIE), and combined field integral equation. To quantify the impact of mesh element size, approximate integration of moment matrix elements, and geometrical discretization error on the accuracy of computed surface currents and scattering amplitudes, we derive error estimates analytically for the circular cylinder. For pulse functions and point testing, current and scattering amplitude errors are generally second order in the mesh element width. The convergence rate worsens to first order if low-order numerical quadrature is used to evaluate moment matrix elements with the EFIE formulation, or if a flat-facet mesh is employed with the MFIE formulation. Third-order convergence is also possible in some special cases. These results for the circular cylinder are empirically compared to computed error values for other smooth scatterer geometries. Convergence rates with respect to mesh refinement agree, but scatterers with regions of high curvature exhibit increased absolute error. [ABSTRACT FROM AUTHOR]

We consider the solution of the time-harmonic Maxwell's equations inside a bounded domain on the boundary of which various conditions are prescribed, including a perfectly matched layer (PML) termination. This problem arises when, e.g., the electromagnetic fields scattered from an inhomogeneous penetrable structure are computed by using a hybrid finite element (FE) and integral equation method in conjunction with a domain decomposition technique. In each of the subdomains, the discretization process leads to a linear system, and an iterative solver may be advantageously utilized when the number of unknowns is large. In this case, the number of iterations and, hence, the computational time required to achieve a given numerical accuracy are known to increase with the condition number κ of the FE matrix. In this paper, we attempt to draw the rules that govern the behavior of κ. To this effect, an eigenmodes technique is proposed that allows to dissociate the influence of the FE mesh and FE basis functions from the one of the actual physical cavity. Numerical examples are provided for one- and three-dimensional problems that illustrate the results so obtained. [ABSTRACT FROM AUTHOR]