
9.2 Dynamic Circuits with Periodic Inputs – Analysis by Fourier Series
A waveform v (t) is periodic on t with a period of T if and only if the following condition is
satisfied by it for all t and n where n is a positive integer.
v t v t nT t n n( ) ( ), ; , , , .= ± =for any and for any 1 2 3 …
This implies that the values of v(t) at similarly positioned time points, at an interval of T seconds
between adjacent points, will be same.
Obviously, if v(t) is periodic it must extend from -∞ to +∞ in the time-axis, since the value of integer n
in the definition of periodicity is not limited to any finite number. Therefore, it is equally obvious