Research ArticleOptimal performance of networked control systems under the packet dropouts and channel noise

- Two explicit expressions of the optimal tracking performance of NCSs are given.
- Optimal performance is constrained by plant internal structure and networked parameters.
- Optimal performance can be improved by considering encoder-decoder.
- Two-parameters controllers can improve the tracking performance.

The optimal tracking performance of single-input single-output (SISO) discrete-time networked control systems (NCSs) with the packet dropouts and channel noise is studied in this paper. The communication channel is characterized by three parameters: the packet dropouts, channel noise and the encoding and decoding. The explicit expression of the optimal tracking performance is obtained by using the spectral factorization. It is shown that the optimal tracking performance dependents on the nonminimum phase zeros, unstable poles of the given plant, as well as the packet dropout probability, channel noise and the encoding and decoding. The optimal tracking performance is improved by two-parameter compensator. Finally, a typical example is given to illustrate the theoretical results.