Characteristic Modes Obtained Using Conventional Characteristic Mode Analysis and Singularity Expansion Method : A Comparison

Both the conventional characteristic mode analysis (CMA) involving impedance matrix diagonalization and singularity expansion method of scattering decomposition essentially depend on the object dimension. In this paper, we have presented a comparative study of the modes extracted for canonical metal objects using both techniques. The matrix pencil method (MPM) of singularity expansion was used to extract natural resonance frequencies from the scattered field of various metal objects and is being compared with the resonance frequency of different modes obtained using CMA. Findings reveal that for highly resonant objects, the resonance frequency obtained using CMA approaches the natural resonance frequency obtained using SEM. However, for lower aspect ratio objects, the resonance frequency obtained using CMA is not equal to the natural resonance frequency attained using SEM.