The exploitation of sparse-matrix techniques in conjunction with the piecewise harmonic-balance method for nonlinear microwave circuit analysis

A novel sparse-matrix approach to the simulation of nonlinear microwave circuits by the Newton-iteration-based piecewise harmonic-balance technique is presented. Selected elements of the Jacobian matrix are set to zero according to some physical criterion, which leads to a sparse Jacobian with a preselected pattern of nonzeros. This allows the use of specialized sparse-matrix solvers, with an effective optimization of both memory storage and CPU time. The code has been developed in both a scalar and a vectorized version optimized for the Cray Y-MP supercomputer.<>