Abstract
In this work, a new method for stopband extension in both open-ended and interdigital parallel-coupled line filters is presented. This method is intended for the suppression of spurious bands which inherently appear in the stopband of this kind of filters. The multispurious suppression is achieved by means of a precise control of the coupling between resonators at unwanted resonant frequencies. The coupling section lengths between successive resonators are used as control parameters to obtain the required couplings. The dependence of the coupling coefficients on coupling section lengths at resonant frequencies is given by closed expressions, obtained following an energetic coupling approach. Several microstrip bandpass filters designed following the new method are presented as examples. These filters feature wide spurious-free bands with high rejection levels.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
