Improved L/sub 2/-sensitivity for state-space digital system

An improved L/sub 2/-sensitivity measure for linear state-space digital systems is presented. It gives a more precise evaluation of the transfer function deviation /spl Delta/H(z) between the infinite wordlength system and the finite wordlength system when the structure matrices {A,b,c} contain 0 and /spl plusmn/1 coefficients. This measure can be applied in the system optimization, resulting in a computationally efficient and very low L/sub 2/-sensitivity structure. The theoretical result is verified by a numerical example.