EECS20N: Signals and Systems

Time-Based Signals vs. Event Sequences

  • Event sequences:
    • x: Naturals0Symbols
  • Discrete-time signals:
    • x: Naturals0RealsK
    • x: IntegersRealsK
  • Continuous-time signals:
    • x: Reals+ → RealsK
    • x: RealsRealsK

The difference between event sequences and discrete-time signals is largely one of interpretation: what is meant by the index in the domain? Time or just ordering? Also, time-based signals more commonly have values in RealsK for some natural number K.

Hybrid systems combine time-based signals with event sequences.