(→Periodic / Non-Periodic Functions) |
(→Periodic / Non-Periodic Functions) |
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Ex1: y[n] = 1 is continuous | Ex1: y[n] = 1 is continuous | ||
| − | Ex2: x[n] = cos[n] is non- | + | Ex2: x[n] = cos[n] is non-periodic |
Revision as of 20:04, 4 September 2008
Periodic / Non-Periodic Functions
CONTINUOUS TIME (CT) For a function to be continuous in discrete time, it must satisfy $ a(x+T) = a(x) $ for any T greater than zero. Furthermore, any continuous time function that does not satisfy the pre-mentioned condition can be deemed non-periodic.
Ex1: y(t) = cos(t) is periodic
Ex2: x(t) = e^3t is non-periodic
DISCRETE TIME (DT) For a function to be continuous in discrete time, it must satisfy $ a[n+T] = a[n] $ for an integer T. If these conditions are not met, then it is deemed non-periodic. Furthermore, both sin and cosine are non-periodic in discrete time.
Ex1: y[n] = 1 is continuous
Ex2: x[n] = cos[n] is non-periodic
