Method of Analytical Regularized Combined Field Integral Equation H-matrix

CFIE is a linear combination of Electric Field Integral Equation (EFIE) and Magnetic Field Integral Equation (MFIE). CFIE suffer from inaccuracies and instability due to ill-posedness of EFIE and numerical singularity error in both EFIE and MFIE. As the number of unknowns grows, inaccuracies may jeopardize the solution. These inaccuracies can be overcome by using the regularization method. We show analytical regularization of CFIE H-matrix based on the diagonalization of the analytically computed near-field matrix. The diagonalized near-field system of equation, in combination with the far-field matrix, is converted into the Fredholm integral equation type of the second kind. The integral equation of the second kind gives a smoother kernel and stable solution.