Further results on Hankel singular values and vectors of a class of infinite dimensional systems

Considers the Hankel singular value problem for a class of infinite dimensional systems. The class consists of Hankel operators whose symbol is a polynomial of a general inner function with coefficient in stable rational functions. This is a generalization of commensurate delay systems to include a wider class of systems. The paper makes use of the system having a Hamiltonian matrix working on the Beurling subspace