SYMMETRICAL QUASI-ELLIPTIC 2-POLE DIELECTRIC RESONATOR FILTER

A new theoretical analysis based on the contribution to the dual mode filter response of each HEM(11) mode polarisation and of higher order modes is presented. This analysis can be applied to any type of microw ave dual mode filter. A description is given for a DR filter. The resu lts enable the presence or absence of two transmission zeros in the fi lter responses to be explained. It is shown how the frequency position of the transmission zeros can be adjusted independently, to produce s ymmetrical dual mode filter responses.