ABSTRACT
The classical definition of the SISO system transfer function determines it as the ratio of the Laplace transform of the system output to the Laplace transform of the system input under all zero initial conditions. It is then explained that the transfer function is the Laplace transform of the unit impulse response of the system under all zero initial conditions. For the MIMO system, its transfer function matrix is consequently defined as the matrix composed of the system transfer functions, which relates the Laplace transform of the output vector to the Laplace transform of the input vector under all zero initial conditions [7], [15], [22], [85], [86], [87], [90], [106], [107], [108], [109], [114].
