Revisiting Minimal Realizations [Lecture Notes]
Mohammadreza Kamaldar, Sneha Sanjeevini, Dennis S. Bernstein · IEEE Control Systems · 2021
Although realizations of transfer functions are a standard topic in textbooks about linear systems theory, this article focuses on several points that are not widely treated. First, it is shown that, for a given dynamics matrix A, the smallest number of sensors and actuators that can be used to form a minimal realization is determined by properties of the Jordan form of A. This leads to the notions of minimally sensed and minimally actuated systems. Next, the rank of a transfer function is related to properties of the Jordan form of A and the rank of the Rosenbrock system matrix.