Time domain analysis of a common-mode suppression filter subjected to a multi-objective optimization

An optimal common-mode suppression filter for a bend discontinuity in a pair of differential lines is characterized simultaneously by a large reduction of conversion noise, a small differential mode reflection coefficient and low overall loss, taking into account technology constraints. To find the geometrical parameters of such optimal design, a novel constrained multi-objective optimization method, relying on intermediate surrogate models of several costs, is proposed. A 3D Pareto-front is generated and further, constrained to impose hardware limitations. The front shows trade-offs between the different cost functions, as such allowing to choose an optimal solution from a large set of available layouts. As is often the case, the filter design occurs in the frequency domain. Additionally, in this contribution the method is also validated by means of a time domain analysis, confirming its accuracy and efficiency.