Page 418 - Schaum's Outline of Theory and Problems of Signals and Systems
P. 418

CHAP. 71                       STATE SPACE ANALYSIS

























                                                   Fig. 7-19




                       where







                       Thus,  the  eigenvalues  of  A  are  A, = $  and  A,  = ;.  Since  IAzl > 1,  the  system  is  not
                       asymptotically stable.
                  (b)  By Eq. (7.44) the system function  H(z) is given by
















                  (c)  Note that there is pole-zero cancellation in  H(z) at  z = :.  Thus, the only pole of  H(z) is
                       I
                         which lies inside the unit circle of  the z-plane. Hence, the system is BIBO stable.
                          Note that even though the system is BIBO stable, it is essentially unstable  if  it is not
                       initially relaxed.


            7.33.  Consider an  Nth-order discrete-time LTI system with the state equation




                  The system  is  said  to be  controllable  if  it  is  possible  to find  a  sequence of  N  input
                  samples  x[n,], x[n, + 11, . . . , x[n, f N - 1]  such  that  it  will  drive  the  system  from
                  q[n,] = q, to q[n, + N] = q, and q, and q, are any finite states. Show that the system
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