Characteristic Mode Equations for Impedance Surfaces

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Research units


Characteristic mode formalism is presented for closed surfaces modelled with the impedance boundary condition (IBC). The characteristic equations are expressed in terms of the electric, magnetic and combined field integral operators (EFIO, MFIO and CFIO). Similarly as for perfectly conducting (PEC) surfaces, the modal solutions based on EFIO (MFIO) are corrupted by spurious solutions as the frequency coincides with the internal resonance frequency of a cavity with PEC (PMC) walls, whereas the CFIO-based approach gives physically correct modal solutions.


Original languageEnglish
Pages (from-to)487-492
Number of pages7
JournalIEEE Transactions on Antennas and Propagation
Issue number1
Publication statusPublished - Jan 2018
MoE publication typeA1 Journal article-refereed

    Research areas

  • Boundary conditions, Characteristic modes, combined field integral equation, Eigenvalues and eigenfunctions, Impedance, impedance boundary condition, Integral equations, Mathematical model, Resonant frequency, spurious solutions, Surface impedance, surface integral equation method

ID: 16401191