Breaking Down the Name
  • Discrete: finite equally-spaced values, rather than infinitesimally smaller-spaced values.
  • Signal: some action that is used to convey information or instructions. E.g. voltage, current, or power.
  • Discrete Time: a sampling (some portion of) Continuous Time
  • Discrete-Time Signal: an action measured across finite equally-spaced values of time
Notation
  • \(x[n]\) implies x exists at discrete values of t
    • Typically n is an integer value.
    • n is synonymous with sample. E.g n=0 is the first sample, n=1 is the second sample...(beware, though, MATLAB is not zero indexed)
  • \(x(t)\) implies x exists at continuous values of t1
  • \(x[n]=x(nT_s)\) where
    • Ts is the Sampling Interval, the reciprocal of the [[Sampling Frequency]]

Discrete:
750
Continious:
750

Where there is charity and wisdom, there is neither fear nor ignorance.
— Francis of Assisi

  1. x(t) is not necessarily guaranteed to be continuous on it's entire domain. ↩