Fully understand the concept of Fourier transform and wavelet (5)--Fourier series expansion function term series

1.4 Fourier series expansion

Before we introduced the Taylor expansion, we mentioned Fourier series. Using Fourier series to expand the function is better than the Taylor expansion, and the smoothness of the function is no longer demanding. Fourier series is the basis of Fourier transform, Fourier transform is a very important method in digital signal processing (especially image processing). Unfortunately, it is not easy for many readers to associate the Fourier transform with the Fourier series referred to in higher mathematics. In this section we are going to unravel the doubts in the reader's mind.

If you are not familiar with the underlying issues covered in this article, it is recommended that you read the sections earlier in this article. Hope that the reader can accumulate, consolidate the foundation.

fully understand Fourier transform and wavelet (1)--Master

http://blog.csdn.net/baimafujinji/article/details/10931621

Fully understand Fourier transform and wavelet (2)--three mean value theorem

http://blog.csdn.net/baimafujinji/article/details/11679839

Fully understand Fourier transform and wavelet (3)--Taylor formula and its proof

http://blog.csdn.net/baimafujinji/article/details/11707407

Fully understand Fourier transform and wavelet (4)--Euler formula and its proof

http://blog.csdn.net/baimafujinji/article/details/45194703

Not finished, to be continued ...

Fully understand the concept of Fourier transform and wavelet (5)--Fourier series expansion function term series