**Tasks to do: **

**Signals for processing***Sum of harmonic components*

Generate the signal as sum of sinusoidals of different frequencies over full frequency band__Generation code:__

fs=8000;

t=0:2*fs-1;

s=zeros(1,2*fs);

for f=100:100:fs/4-100,

s1=f*sin(2*pi*f*t/fs);

s2=f*sin(2*pi*(fs/4+f)*t/fs);

s=s+s1+s2;

end;*Speech signal**sm1.bin*- fs = 16 kHz (utterance "Mobilní hlasová shránka" - male - raining)*sf1.bin*- fs = 16 kHz (utterance "Mobilní hlasová shránka" - female)*sm2.bin*- fs = 16 kHz (utterance "1 0 6 4 7" - male)*sf2.bin*- fs = 16 kHz (utterance "1 0 6 4 7" - female)

- Split the signal into two symetrical frequency bands:
- Design filter bank into following two frequency bands:
*0 - fs/4*a*fs/4 - fs/2*. - Filter analyzed signal.
- Observe spectral characteristics of the signals in particular
bands.
**Attention !**For sinusoidal observe short-time DFT spectrum, for Speech observe spectrgrams ! - Add separated signals and evaluate power of error signal (i.e. difference between original and output)

- Design filter bank into following two frequency bands:
- Decimation
- Realize decimation 1:2 for original signal and also for signals in
particular bands.

ATTENTION !!! It is not possible to use function*decimate*from Signal Processing Toolbox because it uses always low-pass filtering !!! You must realize it by direct removing of given signal samples. - Observe spectral characteristics of all signals before and after decimation and explain results.

- Realize decimation 1:2 for original signal and also for signals in
particular bands.
- Interpolation
- Insert zeros between samples of decimate signals and observe spectral characteristics of these signals.
- Realize the interpolation for both bands using suitable filtering. Observe again spectral characteristics of output signals.
- Add signals after interpolation and evaluate again the power of error signal and compare with previously evaluated results for the synthesis without decimation and interpolation.

- Try to realize splitting into 4 frequency bands, including
decimation and interpolation. Take care about following problems:
- decimation order,
- changes of spectral characteristics in particular bands,
- changes in interpolation procedure.