Computation of Best Sampling time for Removal of DFM in Terms of DFM Radius

It is well established that the Decentralized Fixed Mode (DFM) remains invariant when applied to a Linear Time-Invariant (LTI) decentralized controller. On the other hand, some type of DFM named unstructured DFM(UDFM) can be eliminated by introducing sampling for all most all sampling time. In this paper, the best sampling time for removal of DFM is computed by using real DFM radius for sampled systems under various sampling period, where the real DFM radius measures the closeness of a decentralized LTI system is from having a DFM present. The proposed method for computing best sampling time is verified with a numerical example