Vocabulary

Section: Introduction

Causality

  • A signal $s$ is causal iff $s(t) = 0$ $\forall t <0$

Stability

  • A signal $s$ is stable iff $\Vert s \Vert_1 < +\infty$

Finite Energy

  • A signal $s$ has a finite Energy iff $\Vert s \Vert_2 < +\infty$

Realizable

  • A signal $s$ is realizable iff $s$ is stable and causal.