Interpolation with constraint on frequency region and systems & control application

This paper elaborates on a bitangential interpolation problem with a norm constraint of the interpolant on a given frequency region (and on its generalization), and proves that it admits a solution. A motivation from systems & control for the problem is given, and the solution is applied for construction of a stabilizing control for one-block plants such that the closed-loop transfer matrix is norm-constrained on the frequency region. Illustrative numerical examples are given.