12 Biomedical Engineering Fundamentals
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Fig. 12.13 Periodic cosine signal
Fig. 12.14 Aperiodic exponential signal
12.3.1.2 Periodic and Aperiodic Signals
The signal which follows repetition after a time interval is known as periodic signal.
For a given signal x(t), it can be mathematically expressed as follows:
x(t) = x (t + T )
(12.3)
Here, T is known as the period of the signal.
Sine and cosine waves are examples of periodic signals and Fig. 12.13 shows an
example of periodic cosine signal.
On the other hand, the aperiodic signal does not satisfy the abovementioned
condition in Eq. (12.3). An example of aperiodic signal is shown in Fig. 12.14.