(J,J')-LOSSLESS FACTORIZATION FOR DISCRETE-TIME-SYSTEMS

The (J,J')-lossless factorization problem for discrete-time systems is considered using a bilinear transformation approach. Necessary and su fficient conditions for the existence of the (J, J')-lossless factoriz ation are given in terms of two discrete-time algebraic Riccati equati ons whose solvability can readily be checked. A state-space characteri zation for the (J: J')-lossless factorization is provided. Compared wi th the derivation given in Kongprawechnon and Kimura (1996), our solut ion is more concise and our result takes a simpler form which does not require the system matrix to be non-singular.