Tar81
Newbie level 1
Hi everybody,
I have a problem related to importing coefficients in Digital Filter Design toolbox in MatLab. I wrote an m-file, which allows to find bandpass FIR filter coefficients h(t). When I perform FFT of h(t) in this m-file, I find the frequency response of this filter. But when I pass these coefficients to Digital Filter Design toolbox, the result is different. I found that the toolbox uses freqz function (it performs z-transform, if I understand it right, not FFT). Can I do something, for example multiply h(t) by some function in the m-file, then pass it to toolbox so that the result was the same as fft? In other words, how can I change the function that the zeros lied exactly on the unit circle so that z-transform was the same as the Fourier transform?
I have a problem related to importing coefficients in Digital Filter Design toolbox in MatLab. I wrote an m-file, which allows to find bandpass FIR filter coefficients h(t). When I perform FFT of h(t) in this m-file, I find the frequency response of this filter. But when I pass these coefficients to Digital Filter Design toolbox, the result is different. I found that the toolbox uses freqz function (it performs z-transform, if I understand it right, not FFT). Can I do something, for example multiply h(t) by some function in the m-file, then pass it to toolbox so that the result was the same as fft? In other words, how can I change the function that the zeros lied exactly on the unit circle so that z-transform was the same as the Fourier transform?