Sensitivities of band-edge selectivities

Many filters have a band-edge selectivity (BES) that is a function of param eters other than filter order. In these cases, the band-edge selectivity ca n be maximized without increasing the order of the filter. However, in incr easing BES, we must keep track of the sensitivity of BES to the parameters. In this paper, we provide sensitivities of BES to filter parameters for a variety of classical filters, these being described by rational functions a pproximating the ideal filter magnitude response. The results are useful in the design of such filters.