filter characterization

[tj.diego]

Hello,

i did a filter characterization and now i would like to do a post-correction in the frequency domain, do you have any idea i can proceed!!?

Thanks

[sisu84]

Hi tj.diego,

what information do you have about your filter?

What kind of correction would you like to to?

Ciao!

[tj.diego]

Hello thanks for reply,

actually is not just a filter is a preamplifier, i have done the gain characterization in the frequency domain and i would like to correct it using a kind of lookup table!

[MarcoMar]

In wich way do you want to correct it?

[tj.diego]

i thought just to correct the gain value for each frequency!!! but i have some problem to select the right frequency from the frequency domain and also with the frequency step!

[MarcoMar]

I know you are trying to do an equalization. I asked you how did you plan to implement it. 
What is the form of the signal you are trying to equalize? Is it a waveform or what else? Wich are the inputs of the equalzier? Wich are the outputs? Do you use any input/output hardware?
You have explain in details what you are trying to do. Please, post some codes or schematic block, otherwise I cannot help you.

Regards,

[tj.diego]

right...

the input signal is a waveform (ae) and i would like to process a fft, correct the gain, and return into the time domain, or in other way filter the signal to select the right frequency correct the gain and rebuild the signal.

what do you think is the best way?

[MarcoMar]

You have to find the frequencies you need do amplify/attenuate and then you have to apply a series of filter directly to the waveform in order to do it.

[tj.diego]

so the idea to use the fft is not feasible?

[MarcoMar]

FFT can be a way to know the amplitude of the frequency components of the signal, but you need to use filters to modify the waveform.