Sinc Prototype Filter design

Hello,

Could you please help me in the following sinc filter design?

    % numFFT = 1024;           % Number of FFT points
    %toneOffset = 2.5;        % Tone offset or excess bandwidth (in subcarriers)
    %L = 513;                 % Filter length (=filterOrder+1), odd

    %numDataCarriers = 600;    % number of data subcarriers in subband
    %halfFilt = floor(L/2);
    %n = -halfFilt:halfFilt;

    % Sinc function prototype filter
    %pb = sinc((numDataCarriers+2*toneOffset).*n./numFFT);

1-What is the meaning of (numDataCarriers+2*toneOffset) in this sinc function?How it is interpreted in time and frequency domains?

2-Why it is devided by the FFT length numFFT?

3-What are the sampling period, sampling rate,sampling frequency with this filter design?

4-Why we add 2*toneOffset in to this prototype design?

Thanks in advance!

Answer 1

[Abhishek Ballaney]

https://in.mathworks.com/help/signal/ref/sinc.html

[Tuncay Eren]

thanks Ahishek but I don't understand what that code (in your link) says as well. I would be glad if you could help for above code. thanks