A discrete-time unit-step signal is a signal that has a constant value of 1 for all time indices greater than or equal to zero and a value of 0 for all time indices less than zero.
In mathematical notation, the discrete-time unit-step signal is often represented as $u(n)$, where:
$ u(n) =
\begin{cases}
0, & n < 0.\\
1, & n \geq 0.
\end{cases}
$
![[learnius/slp/4 Speech Signal Representations/attachments/escalao.svg|500]]
The unit-step signal can be related to the [[discrete-time unit impulse]] by:
$
\delta(n) = u(n) - u(n-1)
$