Periodic signals
A periodic signal is one that for a given real number "a": $ x(t) = x(t+a) $
http://en.wikibooks.org/wiki/Signals_and_Systems/Periodic_Signals
A periodic signal is one that for a given real number "a": $ x(t) = x(t+a) $
http://en.wikibooks.org/wiki/Signals_and_Systems/Periodic_Signals