Satisfactory estimation of linear discrete periodic systems
线性离散周期系统满意估计

The state estimation is studied for linear discrete-time periodic systems.Regional pole index for the (periodic) estimation error system is brought up through lifting technique and the other indices of steady state error covariance and (H-infinity) for the periodic error systems are required at the same time.On the basis of satisfactory control theory,a satisfactory (estimator) for the periodic error system with the above three requirements can be designed by using algebra Riccati matrix inequality and numerical recursion algorithm and this problem of satisfactory estimation can be converted into linear programming problems by linear matrix inequalities (LMI) technique and then a feasible satisfactory estimating sketch is achieved by using LMI tool.(Finally) a numeric example checks the above sketch and approach.