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This section generalizes the method presented before for discretization of continuous‐time LTI systems and describes how the continuous‐time LTV system (2.36) and (2.37) can be discretized. Solving the differential equation in (2.36), we obtain:

(2.56)

where is the state‐transition matrix as described in (2.40) and (2.41). Using zero‐order‐hold sampling results in a piecewise‐constant input , which remains constant at over the time interval . Setting and , from (2.56), we will have:

(2.57)

Therefore, dynamics of the discrete‐time equivalent of the continuous‐time system in (2.36) and (2.37) will be governed by the following state‐space model [19]:

(2.58)

(2.59)

where

(2.60)