(3) Approximations of low-pass filter with finite-length cut-off regions

Symbolic solution 

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Numeric cutoff frequency 

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Desired frequency response 

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Corresponding ideal impulse response 

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Approximate ideal filter (L = 21)

Impulse response 
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Approximate ideal filter frequency response 
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Approximate ideal filter (L = 41)

Impulse response 
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Approximate ideal filter frequency response 
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Approximate ideal filter (L = 101)

Impulse response 
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Approximate ideal filter frequency response 
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Converted by Mathematica      March 25, 2003