Extremum-Seeking Boundary Control for Schrödinger-Type PDEs
Paulo Henrique Foganholo Biazetto, Gustavo Artur de Andrade, Tiago Roux Oliveira, Miroslav Krstic
TL;DR
The paper tackles real-time optimization of a boundary-controlled Schrödinger-type PDE with an unknown quadratic performance map. It advances a novel ES framework in which complex-valued states are mapped to a real $2\times2$ representation, enabling Newton-based Hessian inverse estimation, while a two-step backstepping strategy compensates for actuation dynamics. The main contributions are (i) first application of ES to complex-valued PDEs, (ii) a constructive backstepping-based actuation compensation, and (iii) an averaging-based analysis proving convergence to a neighborhood of the extremum with local exponential stability of the Schrödinger dynamics. Numerical results validate the method and illustrate convergence behavior under the proposed ES law. This work broadens data-driven adaptive optimization for dispersive PDEs and offers a practically implementable boundary-control approach for quantum- and wave-like systems.
Abstract
This paper addresses the design and analysis of an extremum-seeking (ES) controller for scalar static maps in the context of infinite-dimensional dynamics governed by complex-valued partial differential equations (PDEs) of Schrodinger type. The system is actuated at one boundary, and the map input is defined as a real-valued quadratic functional corresponding to the squared norm of the complex state at the uncontrolled boundary. An isomorphism between the complex Hilbert space and its two-dimensional real-valued representation is established to enable the use of the standard multivariable Newton-based ES method. To compensate for the PDE actuation dynamics, a boundary control strategy based on a two-step backstepping procedure is employed. With a perturbation-based estimate of the Hessian inverse, the local exponential stability to a small neighborhood of the unknown extremum point is proved. A numerical example illustrates the effectiveness of the proposed extremum-seeking methodology.
