Design of Observers for Positive Systems with Delayed Input and Output Information

This brief is concerned with a new problem of synthesizing linear functional observers for positive systems subject to input and output delays. Without instantaneous information, the synthesized functional observers exclusively use delayed input and output measurements to estimate the functional state vector. The designed observers of the same order as the functional state vector are guaranteed nonnegative and stable. Furthermore, conditions for the establishment of the linear positive functional observers are formulated in terms of convex programming. Numerical examples are carried out to demonstrate the proposed design method.