Measuring the couplings of MIMO dynamic systems: An information-theoretic approach

From the viewpoint of information theory, we proposed a novel concept of information coupling (IC) between the variables of MIMO dynamic system. Two kinds of measures of information coupling strength (ICS) were formulated in terms of mutual information rates. We also derived the frequency formulae of information coupling strengths for MIMO LTI system. Connections between information decoupling and conventional dynamic decoupling of linear system were presented, i.e. the input-output information decoupling (IOID) is equivalent to the input-output dynamic decoupling (IODD), whereas the output information decoupling (OID) is just a necessity for IOID and IODD. Our work shall introduce a new approach for further study of decoupling control under the information-theoretic framework.