In this paper we address the problem of step reference tracking in the context of signal-to-noise ratio (SNR) constrained feedback control. We study the presence of a channel model in the feedback loop either over the measurement path, between the plant and the controller, or the control path, between the controller and the plant. We start the analysis by considering the memoryless additive white Gaussian noise (AWGN) channel model, and follow-up with the additive coloured Gaussian noise (ACGN) channel with memory model. We observe that the standard SNR constrained feedback loop configuration, when tracking step references, will result in an infinite channel SNR. We show that this situation can be ameliorated by extending the feedback loop configuration with an encoder and decoder. The proposed configurations result in a finite SNR that converges back to the infimal SNR for regulation when the amplitude of the reference signal tends to zero.
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Recommended by Associate Editor Young Ik Son under the direction of Editor PooGyeon Park.
The author thankfully acknowledges the support from CONICYT, through research grant FONDECYT/Iniciación 11100 080.
Alejandro J. Rojas received his Ph.D. in Electrical Engineering from the University of Newcastle, Australia in 2007. He held a position as research academic at the ARC Centre of Excellence for Complex Dynamic Systems and Control at the University of Newcastle, Australia from 2007 to 2010. He is currently an Associate Professor at the Universidad de Concepción, Chile. His research interests are in control over network, fundamental limitations, process control and system biology.
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Rojas, A.J. Step reference tracking in signal-to-noise ratio constrained feedback control. Int. J. Control Autom. Syst. 13, 1131–1139 (2015). https://doi.org/10.1007/s12555-013-9283-9
- Control over networks
- performance limitation
- reference tracking
- signal-to-noise ratio