Times and Sines: Fourier Analysis

Abstarct

Fourier analysis breaks a periodic signal up in a series of sine waves, called ­harmonics. Any repetitive physiological signal, such as pressure or flow in the steady state can be written as a Fourier series:

$$ f(t)=\frac{{a}_{0}}{2}+{\displaystyle \sum _{n=1}^{N}[{a}_{n}\mathrm{cos}\frac{2pt}{T}+{b}_{n}\mathrm{sin}\frac{2p}{T}t],}\text {n harmonic number},\text {and N}\ge 0$$