Application of inductive source-load coupling in microstrip dual-mode filter design

The technique to utilise inductive source-load coupling to improve the performance of microstrip dual-mode filters is explored intensively. The functions of the inductive coupling on the filter´s performance, including its potential to generate controllable transmission zeros to create a quasi-elliptic response, is investigated in detail. A demonstration filter has been designed, fabricated and tested to show the validity of the proposed design concept.