ABSTRACT
This chapter presents the basic theory of Fourier series, the understanding of which leads to the application of the analysis to the behaviour of the physical systems. Fourier series is a mode of analysing a periodic function into its constituent components and is a technique developed and named after the French mathematician and physicist Jean Baptiste Fourier. Fourier used the series initially to solve problems in the theory of heat conduction. However, Fourier series have found application in many other fields, such as analysis work in electrical and mechanical vibrations, bending of beams, and in radio waves. The original wave may be analysed into its harmonics and the amplification of each harmonic calculated from the characteristics of the amplifying device. It is possible to determine from Fourier analysis how much of each harmonic is present in the amplified wave and hence the degree of distortion produced. The range of freedom from such distortion is termed the bandwidth of the device.
