Macromodeling of narrow-band bandpass filters based on interpolation of coupling matrices

Microwave filters increasingly exploit complex geometric structures to optimize the performance-to-surface ratio. This often leads to massive electromagnetic (EM) optimization based designs. Lately, macromodel-based designs are proposed as an intuition restoring alternative path. This comes at the cost of a rather numerically expensive model extraction cost. To reduce this extraction cost and to link the macromodel in a design context, the paper proposes to use a macromodel for the low-pass coupling matrix of the filters.