I am new to the fft filter and I want to know the steps of building a fft filter, e.g., what I need to know before I build this filter. In addition, my Matlab has Signal Processing Toolbox installed.
I am given a sequence with 131072 samples, the sampling rate is 500Hz. Also, I want to filter this sequence using low pass filter with cutoff frequency=20Hz.
My question is about the syntax of "fftfilt", how do I generate the coefficient vector b by providing the cutoff frequency(the freq range that i'm interested).
Thanks for your help, Kay