Choice of the filter depends on the application.
Merits of FIR filters -
1) FIR filters have an amazing property called Linear phase. Linear phase property implies that the phase is a linear function of the frequency. It ensures that signals of all frequencies are delayed by the same amount of time, thereby eliminating the possibility of phase distortion. Pretty darn useful in audio applications.
2) FIR filters are always stable i.e. for a finite input, the output is always finite. This property is always useful.
Demerits of FIR filters -
1) For a desired frequency response, with tight constraints on the passband, transition band and the stopband, a FIR filter may have large number of coefficients. An IIR filter can satisfy the constraints with lesser number of coefficients. For the same reason, IIR filters are used for filtering out sensor noise.
If the application demands linear phase, then we go for FIR filters. If there is no linear phase constraint, and the desired frequency response can be approximated by lesser number of coefficients using a stable IIR filter, then we choose IIR filters.
Merits of FIR filters -
1) FIR filters have an amazing property called Linear phase. Linear phase property implies that the phase is a linear function of the frequency. It ensures that signals of all frequencies are delayed by the same amount of time, thereby eliminating the possibility of phase distortion. Pretty darn useful in audio applications.
2) FIR filters are always stable i.e. for a finite input, the output is always finite. This property is always useful.
Demerits of FIR filters -
1) For a desired frequency response, with tight constraints on the passband, transition band and the stopband, a FIR filter may have large number of coefficients. An IIR filter can satisfy the constraints with lesser number of coefficients. For the same reason, IIR filters are used for filtering out sensor noise.
If the application demands linear phase, then we go for FIR filters. If there is no linear phase constraint, and the desired frequency response can be approximated by lesser number of coefficients using a stable IIR filter, then we choose IIR filters.
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