Coisometically Valued Rational Matrix Functions Academic Article uri icon


  • Given signature matrices J 1 and J 2 of possibly different sizes, and a rational matrix function W without a pole or zero at infinity, we indicate a necessary and sufficient condition for the equation J 1 = W (z)J 2 W(z)* to hold on the imaginary axis or the unit circle. The condition makes it possible to characterize inner rational matrix functions without a zero at the origin. We also discuss an application to the factorization.

publication date

  • January 1, 1995