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Altera_Forum
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13 years ago

half-band filter

I am trying to implement a half-band filter in Verilog. The questions are: 1. what is the definition for a half-band filter? Is it the same as what we have in traditional multi-rate DSP "P(z)+P(-z)=c...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
13 years ago

Should a half band filter satisfy P(z)+P(-z)=constant (or P(w)+P(w+pi)=constant) if P(z) is a half band filter? However, in the example http://www.dsprelated.com/showarticle/124.php, this sum is very small around pi/2 compared to its value at 0, pi, 2*pi. Besides, the value also alternates between positive and negative. Is there a problem here?