Design and construction of high performance HTS pseudo-elliptic band-stop filters

Elliptic function band-stop filters play an important role in cellular front end filtering. The AMPS B frequency allocation requires a very narrow (less then 0.2% fractional bandwidth) bandstop filter. The filter developed was a 6th order pseudo-elliptic band-stop design, and presented in this paper will be the design technique used to synthesize this filter. The design techniques described can be extended to any order band-stop filter and a large range of frequencies. Also discussed will be the issues related to the practical implementation of building the physical filter.