Fig 6. The wide band measuremen results compared with
simulation response of the duplexer
The photograph of the fabricated diplexer is shown in Fig. 4, whose
dimensions are 57mm×23mm×21mm (connector size is not included). In Fig.
6, the wide band response of the diplexer, there is one parasitic
transmission zero of the transmitting channel, while there are two
parasitic transmission zeros of the receiving channel. The parasitic
transmission zeros can further enhance remote suppression. Combined with
Fig. 3 and Fig. 5, we know the synthesis results, simulation results,
and tested results are well matched with each other.
Conclusion: In this paper, a novel 2.6G stripline diplexer with
multiple transmission zeros using frequency dependent couplings is
developed. On the basis of the synthesis technique for cross-coupling
filter, by introducing the frequency dependent couplings new
transmission zeros are generated. The diplexer has better frequency
selection characteristics, lower loss, better harmonic suppression
characteristics and higher reliability, and it can be welded and
integrated on the PCB board like the dielectric waveguide diplexer, it
has broad application value.
Acknowledgments: This work was supported by science and technology
project of Jiangxi Provincial Department of Education (GJJ2201211), key
research and development plan of Ganzhou(2022B-GY9645), the natural
science foundation of Jiangxi Province, China (Grant
No.20202BABL201022).
2021 The Authors. Electronics Letters published by John Wiley &
Sons Ltd on behalf of The Institution of Engineering and Technology
This is an open access article under the terms of the Creative Commons
Attribution License, which permits use, distribution and reproduction in
any medium, provided the original work is properly cited.
Received: xx January 2021 Accepted: xx March 2021
doi: 10.1049/ell2.10001
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