ABSTRACT
A finite duration, or periodic, function f (t) can in general be decomposed into a sum of trigonometric or complex exponential functions called Fourier series [32] [57] [71]. The Fourier series, which is then referred to as the expansion of the given function f (t), will
be denoted by the symbol fˆ(t), in order to distinguish the expansion from the expanded
function. The Fourier series fˆ(t) is said to represent the given function f (t) over its interval of definition.
