Optimizing Elliptic Filter Selectivity

AbstractThe problem of determining the band-edge selectivity of elliptic filters and its optimization in filter design is considered. The band-edge selectivity is derived with respect to the $$n$$ -th order elliptic function. The selectivity formula embodies potential trade-offs in filter requirements for improving filter mangitude or delay response. Design examples are submitted in support of the theory. A simple proof describes the Chebyshev filter as an elliptic filter in the limit of infinite stopband corner frequency.