m_eh_62
Member level 2
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in wavelet transform
there are four decomposition and reconstruction filters
by this command:
Lo_D,Hi_D are decomposition filter create by db4 and
Lo_R,Hi_R are reconstruction filter
I want to know each filter characteristic such as :
Bandwidth,cutoff frequency,the type of eah filter(I think these filter are in FIR form)
and the mathmatic equation of these filters.
the frquency response of the Hi_D filter in matlab is :
:?: :?:
but I can't determine Bandwidth,cutoff frequency and the type of this filter?
can anyone help me?it's urgent. :roll:
and to attain mathmatic equation;I find zero and poles of this filter but i 'm not sure by finding the zeros and pole I could reconstruct the filter equation!!!
:?:
how can I find the filter equation?
there are four decomposition and reconstruction filters
by this command:
Code:
>> [Lo_D,Hi_D,Lo_R,Hi_R]=wfilters('db4');
Lo_D,Hi_D are decomposition filter create by db4 and
Lo_R,Hi_R are reconstruction filter
I want to know each filter characteristic such as :
Bandwidth,cutoff frequency,the type of eah filter(I think these filter are in FIR form)
and the mathmatic equation of these filters.
the frquency response of the Hi_D filter in matlab is :
Code:
>> freqz(Hi_D)
![i30440_freqz.jpg](https://imageupload.com/out.php/i30440_freqz.jpg)
:?: :?:
but I can't determine Bandwidth,cutoff frequency and the type of this filter?
can anyone help me?it's urgent. :roll:
and to attain mathmatic equation;I find zero and poles of this filter but i 'm not sure by finding the zeros and pole I could reconstruct the filter equation!!!
Code:
>> zplane(Hi_D)
![i30441_Zplane.jpg](https://imageupload.com/out.php/i30441_Zplane.jpg)
:?:
how can I find the filter equation?