Disturbance decoupling for linear time-invariant systems: a matrix pencil approach

In this note, we give a systematic new analysis of disturbance decoupling p roblems for standard linear time-invariant systems based on the theory of m atrix pencils. This approach is based on the computation of condensed forms under orthogonal equivalence transformations. From these forms, that can b e computed in a numerically stable way, we obtain new necessary and suffici ent conditions that are numerically verifiable, and, furthermore, we immedi ately obtain numerically stable algorithms to compute the desired compensat ors, We present a numerical example that demonstrates the properties of the new approach.