Performance limitation analysis of networked control systems

The performance limitation analysis of single-input-single-output (SISO) networked control systems (NCSs) over signal-to-noise ratio (SNR) constrained channel is proposed in this paper. The performance index is measured by the energy of the error variance response between the output of the plant and the reference signal. The performance limitation is obtained by applying H₂ square error criterion and the spectral factorization technique. It is shown that the performance limitation is constrained by nonminimum phase zeros, unstable poles of a given plant, the power spectral density of a given reference signal and SNR of communication channel. The result obtained in this work explicitly show how is the performance limitation limited by the SNR of communication channel. A typical example is given to illustrate the theoretical results.