Discrete time signals

The signals, which are defined at discrete times are known as discrete signals. Therefore, every independent variable has distinct value. Thus, they are represented as sequence of numbers.

Although speech and video signals have the privilege to be represented in both continuous and discrete time format; under certain circumstances, they are identical. Amplitudes also show discrete characteristics. Perfect example of this is a digital signal; whose amplitude and time both are discrete.

The figure above depicts a discrete signal’s discrete amplitude characteristic over a period of time. Mathematically, these types of signals can be formularized as;

x={x[n]},−∞<n<∞$$x=\left\{x\left[n\right]\right\},-\mathrm{\infty }<n<\mathrm{\infty }$$

Where, n is an integer.

It is a sequence of numbers x, where n^th number in the sequence is represented as x[n].