Output observer design for linear systems: Application to filtering and fault detection

In this paper, we propose an output observer design methodology for linear single output systems. It is shown that, among other potential applications, the proposed observer can be used for filtering and fault detection purposes. Unlike traditional observers that are based on the the state-space representation of the system, the proposed observer design is based on the input-output representation of the system. The main advantage of the proposed observer is its simplicity of design and it has a lower order than the original system.