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Window Choice in FIR filter design

I want to design using the windowed fourier series approach a linear phase FIR lowpass filter of lowest order with the following specifications: passband edge at 0.3pi, stopband edge at 0.5pi, and minumum stopband attenuation of 40dB. Which window function is the best appropriate for this design and why?? (examples: hamming, hanning, blackman....etc)

grg99

IIRC each window has its advantages and disadvantages. Some are going to give you better amplitude accuracy, some better phase accuracy. Some give weird but small artifacts in the stop band, others give regular but larger quirks.

I'd download one of the many excellent filter design applets and play with the window selection buttons.

mte01

ASKER

I want the window that would provide the filter with the least order

JR2003

Sin^2 t

grg99

Hmm, I'm mighty fuzzy on this stuff, but I think applying the window just surpresses the endpoint artifacts and how they appear on the amplitude and phase analysis results. The actual filter design is independednt of this-- the windowingg just helps clear up the picture.

mte01

ASKER

Yes maybe.....

mte01

ASKER

The correct window turned out to be the hanning window.........I want to ask the moderator: should I delete this question grg99's answer with a grade of C??

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Member_2_1840827

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mte01

ASKER

It's amazing how I thought of deleting the question at the same time that you got the correct answer!!!

Yes, you are correct and thanks for the explanation....

Member_2_1840827

You are welcome m8, and thanks for the grade.
Cheers :)
SokhodoM

mte01

ASKER

if you can sokhodom, also have a look at this question: https://www.experts-exchange.com/questions/21219067/Implementing-FFT-algorithms-in-FPGAs.html