In summary, a new quasi-Yagi DGS LPF was developed and offers excellent performance both within its passband and throughout its stopband. The use of a meander feedline helps improve passband and stopband performance compared to a filter without the meander feedline. The novel quasi-Yagi resonator made it easier to control resonant frequency without extra devices, contributing to the compact size of the filter structure. In validation of the design approach used for the quasi-Yagi LPF, the measured results agreed closely with computer simulations of the filter’s performance.

Ahmed Boutejdar, Engineer

Abbas Omar, Engineer

Edmund Burte, Engineer

Microwave and Communication Engineering Institute, University of Magdeburg, Magdeburg, 39106, Germany.

Acknowledgments

The authors wish to thank the German Research Society (DFG) for financial support. The authors are also grateful to Microwaves & RF Technical Contributor Jack Browne for his assistance and cooperation, and to Mr. Harald Dempewolf, Laboratory Manager of the Institute for Electronics, Signal Processing, and Communication (IESK) at the University of Magdeburg, Germany, for his help and support.

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