  The choice of a reference model in data-driven control techniques is a
critical step. Indeed, it should represent the desired closed-loop performances
and be achievable by the plant at the same time. In this paper, we propose a
method to build such a reference model, both reproducible by the system and
having a desired behaviour. It is applicable to Linear Time-Invariant (LTI)
monovariable systems and relies on the estimation of the plant's instabilities
through a data-driven stability analysis technique. The L-DDC (Loewner Data
Driven Control) algorithm is used to illustrate the impact of the choice of the
reference model on the control design process. Finally, the proposed choice of
specifications allows to use a controller validation technique based on the
small-gain theorem.
