Tunable Waveguide Band Rejection Filters

The development of a series of four waveguide tunable band rejection filters designed to eliminate problems in spectrum signature measurements is described. The four filters consist of two C band units (5.0 to 7.0 Gc) and two X band units (8.5 to 12.0 Gc). These filters are tunable over a broad frequency range while maintaining a uniform filter response and a peak rejection in excess of 35 db. The design procedure employed during this development including the theoretical analysis of the cavity and coupling system is presented. The design techniques are directly applicable to many filter designs including band pass filters.