EMI and EMC Analysis of Arbitrarily Shaped Power-Ground Planes

The radiation from a power-ground planes structure in high-speed printed circuit boards due to high switching noise current is investigated in this paper. A 2D contour integral method is used to characterize the radiation from the power ground planes. The contour integral method can model an arbitrarily shaped power-ground planes pair more efficient than 3D numerical methods. By combining the noise current source with the [Z] matrix of power-ground planes, the edge voltage and electric field are obtained. Based on the field equivalent principle, the equivalent magnetic current around the edges of power-ground planes is obtained. Thereafter, the radiated intensity is calculated by equivalent magnetic current and free space Green function.