Shannon Speech and STM32F407 signal filter

代码说明：

Using Matlab to develop a piece of software able to produce what is colloquially referred as ‘Shannon Speech’. The input signal, which is digital, is band-pass filtered into a number of channels. The output of each filter is half-rectified, low-passed filtered and multiplied by white noise. Then the result in each channel is filtered again by another band-pass filter. Finally, the channels are added to form the output.  Generate a signal of frequency 500Hz, 1500Hz and 2500Hz. Using the STM32F407 board to design a filter bank able to remove each of the three frequency components.