MATLAB® and Its Applications in Engineering: [Based on MATLAB 7.5 (R2007b)]

15.2. Signals and Systems Classification

15.2.1. Classification of Signals

Signals are broadly classified into two types: (1) Continuous-time signals (analog signals) and (2) Discrete-time signals (digital signals).

1. Continuous-time signals (analog signals): These signals are defined for every instant of time and take on values in the continuous interval (x, y), where x and y can be ∞. For example,

   x(t) = sin wt

   where −π ≤ wt ≤ π

   Here, wt can assume infinite number of values in the time interval indicated.

   The plot is shown in Figure 15.1.

   Figure 15.1. ‘sine’ Wave as Continuous Signal

   

2. Discrete-time signals (digital signals): The discrete-time signals ...