Determination of a transfer function matrix in multivariable systems

A conceptually simple method is presented for determining the system transfer function matrix of linear multivariable systems described by their state-space equations. The polynomial coefficients of the transfer function matrix are computed directly by using the controllability matrix method and the transformation to canonical (phase-variable) form matrices, even if the transformation matrices are singular. The method does not require matrix inversion and calculation of eigenvalues, and requires only O(n/sup 3/) operations.<>