Reachability indices of periodic positive systems via positive shift-similarity

The problem of the paper is the formulation of the concept of reachability indices of periodic linear positive systems. A positive system is one in which the positive orthant is an invariant subset with respect to positive input signals. The concept of shift-similarity for periodic positive systems is defined and the associated cyclically augmented system is considered. The results are the relation of the positive similarity of both representations, the formulation of the reachability indices, and a detailed example.