Identifying radiation mechanisms on small conducting objects using radiation modes

A modal decomposition based on the real part of the method of moments impedance matrix is used to analyze the radiation mechanisms of small planar conducting objects. Here we show analytically that spatially-uniform current components are solutions to the corresponding continuous eigenvalue operator equation for the real component of the scattered electric field on the surface of the radiating object. Power is predominately radiated through these uniform modes. We present an example demonstrating the relatively small variance of low-order spatially-varying modes on a planar object with various geometry modifications.