- The output of a discrete time LTI system is completely determined by the input and the system's response to a unit impulse.
**Figure 1:**We can determine the system's output, y[n], if we know the system's impulse response, h[n], and the input, x[n].**System Output** - The output for a unit impulse input is called the impulse response.
**Figure 2****Figure 3****(a)****(b)**

**Example Impulses**

Since we are considering discrete time signals and systems, an ideal impulse is easy to simulate on a computer or some other digital device. It is simply a signal that is 1 at the point n = 0, and 0 everywhere else.

Comments:"My introduction to signal processing course at Rice University."