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Real-and Complex-valued Signals

2 June, 2016 - 15:17

A discrete-time signal is represented symbolically as s (n), where n = {..., −1, 0, 1,... }. We usually draw discrete-time signals as stem plots to emphasize the fact they are functions defined only on the integers. We can delay a discrete-time signal by an integer just as with analog ones. A delayed unit sample has the expression δ (n − m), and equals one when n = m.

Figure 2.7 Discrete-Time Cosine Signal
The discrete-time cosine signal is plotted as a stem plot. Can you find the formula for this signal?