23-05-2014, 04:42 PM
Digital Filter Specifications
Digital Filter.ppt (Size: 706.5 KB / Downloads: 115)
Digital Filter Specifications
These filters are unealisable because (one of the following is sufficient)
their impulse responses infinitely long non-causal
Their amplitude responses cannot be equal to a constant over a band of frequencies
Another perspective that provides some understanding can be obtained by looking at the ideal amplitude squared.
Selection of Filter Type
Advantages in using an FIR filter -
(1) Can be designed with exact linear phase
(2) Filter structure always stable with quantised coefficients
Disadvantages in using an FIR filter - Order of an FIR filter is considerably higher than that of an equivalent IIR filter meeting the same specifications; this leads to higher computational complexity for FIR