Electrical Engineering ⇒ Topic : Time Invariant and Time Variant Systems

Time Invariant and Time Variant Systems

Let us consider a continuous time system having output y(t) for an input x(t). An input signal having a time shift is applied to the system, the system is said to be time invariant if and only if the output of the system has the time shift. Mathematically, for a time invariant system, we can write

                            x(t) → y(t)

                           x(t - t_o) y(t - t_o)

On the other hand, for a time varying system, the produced output will not have the identical shift of input.

For example, the differential equations

For a time invariant system, any co-efficient of its representing differential equation should not vary with time.