In experiment 7, we discussed the windowing method of FIR filter design. In this experiment, we use another method of FIR filter design, which is known as the Frequency Sampling Method (FSM).It involves uniform sampling of the desired frequency response, and performing an inverse DFT to obtain the corresponding FIR response. For practical design, we used Scilab. The formulae for DFT and IDFT were incorporated into the code and the filter parameters were taken as user input. Plot function helped us verify the results.
The flow is shown below :
Hd(w)----------------H(k)------------------h(n)
(By sampling) (by IDFT)
It was also observed that a factor of 2*pi has to be added every time a sign change occurs in the magnitude.
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ReplyDeleteThis method is more efficient than the method using window function.
ReplyDeleteYes, in FSM, many signal values become zero during computation
DeleteThis is a comparatively simple technique to implement.
ReplyDeleteYes, this method is faster than the method using window function.
DeleteDft and fft are good transforms
ReplyDeleteYes, they help to reduce computations
DeleteThis method requires less computation than windowing method.
ReplyDeleteYes, this method is faster than the method using window function.
DeleteFSM method is more efficient.
ReplyDeleteYes, this method is faster than the method using window function.
DeleteFrequency sampling methods only guarantee good approximation to the desired response in some frequency values.
ReplyDeleteYes, this method can be used in applications where the desired range is known
DeleteFrequency sampling methods only guarantee good approximation to the desired response in some frequency values. The approximation in other values can be very bad.
ReplyDeleteYes, this method can be used in applications where the desired range is known
DeleteSimplest and direct technique for FIR filter design
ReplyDeleteYes, they help to reduce computations
DeleteIt is less time consuming that window function method
ReplyDeleteYes, this method is faster
DeleteSimpler method compared to windowing as optimisation is easy.
ReplyDeleteYes, it is also faster
Delete