S : FFT of input signal from microphone
Exp : just gain
1/(Q*J) : include frequency component, I convert this equation to frequency domain digital filter using frequency sampling method
and similar process are conducted several time
and i'am doing overlap and save method like this
- zero padding input signal -> fft
- zero padding filter.1 -> fft
- multiplication -> ifft -> discard first block -> y1
- zero padding y1 -> fft
- zero padding filter.2 -> fft
- multiplication -> ifft -> discard first block -> y2
- So on....
my question is if it is impossible to combine all filter to one (cascaded filter) every time fft and ifft and discard process will be conducted that is very inefficient. is there efficient method to filter signal several time in frequency domain?