A Modified Homotopy Method for Nevanlinna-Pick Interpolation with Degree Constraint

Nevanlinna-Pick interpolation with degree constraint can be applied to control theory, signal processing and circuit theory. This paper presents a modified homotopy method to solve nonlinear equations induced by the interpolation problem. The proposed method for computing scalar real rational Nevanlinna-Pick interpolants of a bounded degree includes three parts: homotopy function construction, variable transformation and iteration procedure. The numerical example illustrates the efficiency of the new method.