System identification of time-delay system via discrete-time model with non-integer time-delay

A system identification method for time-delay systems via discrete-time model is proposed. It is assumed that the time-delay is a non-integer multiple of the sampling period. We describe the discretization of such time-delay systems and propose a new interpretation for system identification. Single-input, single-output systems are interpreted as two-input, single-output systems: one represents system dynamics and the other is due to time-delay. Using this interpretation, we propose a system identification method, which estimates the parameters of each system separately. Finally we verify the effectiveness of the proposed method through numerical examples.