Novel input-output representation of general non-uniformly sampled-data systems

The lifted state space model and the corresponding lifted transfer function model have been widely adopted to describe non-uniformly sampled-data (NUSD) systems. However, the lifted models are too complex and involve a large number of parameters, which bring a great challenge to NUSD systems identification and control. Motivated by this fact, we propose a novel input-output representation of general NUSD systems by introducing a time-varying backward shift operator. Based on the novel model, the traditional identification methods and control strategies of single-rate systems can be easily extended to general NUSD systems. The advantages and effectiveness of the novel model are well illustrated by a simulation example.