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EXP 7 - FIR Filter using Window method

After performing IIR Filter Design it was time to start FIR filter Design. In this experiment we have designed an FIR Filter using various Window functions.

Depending on the values of stop band attenuation the appropriate window function chosen like Bartlett, Hamming, Hanning and Rectangular. After execution of code the values of pass band and stop attenuation were verified from the graph.

Comments

  1. Rectangular Window function has the lowest Ap but calculations are drastically reduced..so function has to be chosen according to application also.

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    Replies
    1. The choice of the window depends on the noise characteristics, transition region and the number of coefficients required

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  2. Window function is used to truncate the infinite values of hd(n) and the window is selected based on the stop band attenuation requirement.

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  3. Hanning window provides stop band attenuation of 44db where as Blackman window provides highest attenuation of 74db

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  4. The trick is to select the window function that will give a filter with the correct transition width and attenuation in stopband.

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