Starting from a continuous time linear time- invariant system, a linearly similar variant of the Nagy- Foias functional model of the main operator of the system is constructed. This model is formulated in terms of Hardy H 2 spaces in a semiplane. We give a connection between the construction of this model and the control theory (the input- state and the state-output maps, exact controllability and exact observability, etc.). A pole placement result, expressed in terms of invertibility of a certain Toeplitz operator, is obtained by applying this model. A numerical example of pole placement is given.