Application of two-step preconditioning technique to the Crank-Nicolson Finite-Difference Time-Domain method for analysis of the 3-D planar circuits

In this paper, two-step sparse approximate inverse(SAI)-symmetric successive overrelaxation(SSOR) preconditioned generalised minimal residual (GMRES) algorithms are applied to solve the linear system of equations resulting from the 3-D CN-FDTD method for the simulation of the T junction microstrip circuit. The simulation results demonstrate that the two-step preconditioner can greatly accelerate the convergence of the GMRES iterative method.