MFTI: Matrix-format tangential interpolation for modeling multi-port systems

Numerous algorithms to macromodel a linear time-invariant (LTI) system from its frequency-domain sampling data have been proposed in recent years, among which Loewner matrix-based tangential interpolation proves to be especially suitable for modeling massive-port systems. However, the existing Loewner matrix-based method follows vector-format tangential interpolation (VFTI), which fails to explore all the information contained in the frequency samples. In this paper, a novel matrix-format tangential interpolation (MFTI) is proposed, which requires much fewer samples to recover the system and yields better accuracy when handling under-sampled, noisy and/or ill-conditioned data. A recursive version of MFTI is proposed to further reduce the computational complexity. Numerical examples then confirm the superiority of MFTI over VFTI.