Design of observer based compensators: The polynomial approach

This paper presents the frequency domain design of observer based compensators related to arbitrary observer orders for state reconstruction in direct equivalence to the well known time domain approach. The parameterization of the state feedback and of the state observer problems are possible without recurrence to the time domain representations of the system, however, the equivalent time domain solutions can easily be computed at every design step. An additional result are the doubly coprime factorizations of a system transfer matrix. Thus the results by Nett et al. [13] are generalized to arbitrary observer orders and in addition, the computation of the stable fractional representations becomes possible directly in the frequency domain. A simple example demonstrates the new design.