Harmonic 1: sin(x)
Harmonic 2: sin(2x)
Harmonic 3: sin(3x)
A Fourier series is an expansion of a periodic function f(x) in terms of an infinite sum of sines and cosines. The basic idea is any shaped periodic waveform, can be represented as the sum of a set of sine waves with proper phases and amplitudes. It is essential in many fields especially signal processing. Mathematically, it's defined by the following equations:
The corresponding coefficients are defined as:
For example, to form a sawtooth wave, we have the following summation:
Figure 1: Expansion of a sawtooth wave with 4, 6 and 10 terms