  We study output reference tracking for unknown continuous-time systems with
arbitrary relative degree. The control objective is to keep the tracking error
within predefined time-varying bounds while measurement data is only available
at discrete sampling times. To achieve the control objective, we propose a
two-component controller. One part is a recently developed sampled-data
zero-order hold controller, which achieves reference tracking within prescribed
error bounds. To further improve the control signal, we explore the system
dynamics via input-output data, and include as the second component a
data-driven MPC scheme based on Willems et al.'s fundamental lemma. This
combination yields significantly improved input signals as illustrated by a
numerical example.
