An Approach for the Stability of Communication Constrained Networked Time-delay Control Systems

This paper aims to solve the stability problem of networked time-delay systems by frequency-domain analysis. The communication network quality is affected by bandwidth, noise, and packet dropouts. The main techniques are spectral decomposition and frequency-domain analysis. By means of utilizing those techniques, the expression of minimum signal-to-noise ratio which stabilizes the networked time-delay systems is obtained. Further, it is shown that the minimum value of system stability depends on the certain constraints (bandwidth and packet dropout probability) of communication channel, the position of unstable poles and the non-minimum phase zeros of given model. Moreover, an acquired result clearly brings out the contact among the status of the researched system, communication channel parameters, and the structural property of the considered model. Some simulation examples are given to provide validation of the final result.