|Signal Processing Toolbox|
FIR Filter Design
Digital filters with finite-duration impulse response (all-zero, or FIR filters) have both advantages and disadvantages compared to infinite-duration impulse response (IIR) filters.
FIR filters have the following primary advantages:
The primary disadvantage of FIR filters is that they often require a much higher filter order than IIR filters to achieve a given level of performance. Correspondingly, the delay of these filters is often much greater than for an equal performance IIR filter.
||Apply window to truncated inverse Fourier transform of desired "brick wall" filter
|Multiband with Transition Bands
||Equiripple or least squares approach over sub-bands of the frequency range
|Constrained Least Squares
||Minimize squared integral error over entire frequency range subject to maximum error constraints
||Arbitrary responses, including nonlinear phase and complex filters
||Lowpass response with smooth, sinusoidal transition
|Comparison of Classical IIR Filter Types||Linear Phase Filters|
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