Design and Maximum Error Estimation for Small Error Low Pass Filters

摘要

By using standard spectral windows small error low pass nonrecursive filters may be designed with transition bandwidths inversely proportional to the number of filter weights. The maximum ripple error outside the transition band for any low pass filter using discrete smoothing by the three most standard spectral windows is estimated. Consequently, the straightforward design equations may be used to calculate low pass digital filter weights with a guaranteed maximum error of less than 0.9% or 0.05% depending on how wide the transition band is made. Filters designed in this way have errors comparable to or smaller than those of filters designed by existing techniques and have the advantage that the maximum error is known beforehand. (Author)