Reduced-order dynamic observer error linearization for discrete-time systems

This paper addresses reduced-order dynamic observer error linearization (RDOEL) for discrete-time systems, which is a modified version of dynamic observer error linearization (DOEL). We define the concept of RDOEL and provide a necessary and sufficient condition for RDOEL. Moreover, we discuss the relation between RDOEL and DOEL when the auxiliary dynamics is an arbitrary linear controllable system. Using the relationship and an existing algorithm for DOEL, we also propose an algorithm for RDOEL that offers lower dimensional observers than DOEL. Finally, a simple example is included to illustrate the theory.