How to used firpm.m function?

Hiii

I am working with a code where i tried to construct a wiener filter. I used firpm function and this function requires an array of f where i can give the ranges of frequencies to define my pass and stop bands. I dont know how to define f. I am also giving the code for firpm.

firpm(order,[0 0.156 0.43 0.62 0.82 1],[0 0 1 1 0 0],[10,1,10])

I dont know how to get [0 0.156 0.43 0.62 0.82 1]. Do i need to define these values by signal fft magnitude spectrum? but again i dont know how.

Any help will be highly appreciated.

Answer 1

[Honglei Chen]

That is your frequency vector that contains the boundaries of your pass bands and stop bands. In your example, it means that you have a stop band between 0 and 0.156, a pass band between 0.43 and 0.62 and a stop band between 0.82 and 1. The frequency values are determined by your application, i.e., what are the frequencies you want to pass and what are the frequencies you want to stop. You can find more information in the doc page

http://www.mathworks.com/help/signal/ref/firpm.html