The IIR filters correspond to infinite impulse response. FIR filters have finite impulse response i. e. length of h[n] is finite. In windowing method, To obtain desired h[n], IDTFT of desired frequency response is calculated. But this desired h[n] has infinite samples. To obtain finite h[n], window functions are used. Selection of window function depends on parameter As. On putting the values of As, Ap, fs, and fp in the code, the appropriate window function was selected and order was calculated.
The method uses appropriate window function using value of As given as an input. So filter design is optimum.
ReplyDeleteWhen 'As' requirement increases, the complexity of corresponding window function also increases
DeleteUseful info.
ReplyDeleteNice!
ReplyDeleteWindowing method is better than FSM to find optimum output.
ReplyDeletehere are side lobes present in frequency response due to discontinuity in the window function
ReplyDeleteThe side lobes should have as less energy as possible. Most of the energy should be contained in Main lobe
DeleteRectangular window is a window function with lowest stop band attenuation.
ReplyDeleteBlackman window function has largest value of stop-band attenuation.
DeleteWe don't need to use direct form 2 method and thus save on number of multipliers
ReplyDeletethe window is chosen depending on the application.
ReplyDelete