In the discrete time t, yt, ut, output and input signals; number d of discrete delay and the sampling period; ξt, the control system interference; q, inverting (delaying) the operator; A (q1), B (q1), backward operator q-1 polynomial.
In discrete time t, yt, ut, output and input signals; d discrete delay and number of sampling cycles; A (q1), B (q1), the polynomial of the post-operator q-1.
In discrete time t, YT, UT, output and input signals; D discrete delay and number of sampling periods; ξ T, control system interference; Q, inversion (delay) operator; a (Q1), B (Q1), polynomial of backward operator Q − 1.