Two architectures of fully-planar differential-mode dual-band bandpass filters (DB-BPFs) with enlarged common-mode-suppression bandwidth are reported. The first one, which aims at designs with broadly-separated wide passbands, exploits the loading of extra lines in its balanced symmetry plane. Thus, multiple common-mode transmission zeros (TZs) are created to make wider the DB-BPF common-mode-rejection range. The second one can be used for realizations with closely-spaced passbands and employs a properly-balanced quasi-bandpass-type DB-BPF topology. In this case, the common-mode-mitigation bandwidth broadening is performed by adequately selecting the type of implementation for the short-circuit terminations of its resonating lines- i.e., virtual or physical short circuits in the differential-mode operation-. For experimental-validation purposes, two microstrip DB-BPF prototypes are manufactured and tested.
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Wide‐band signal‐interference duplexer with contiguous single/dual‐band channels and its application to quasi‐absorptive bandpass filters
A type of wide‐band signal‐interference planar duplexer with single‐ and dual‐band channels is presented. It exploits transversal‐signal‐interference‐section‐based channels with contiguous single‐ and dual‐passband filtering transfer functions. Furthermore, by ending the dual‐band channel in a reference‐impedance resistor, a wide‐band bandpass filter (BPF) with quasi‐absorptive stopbands is realised. As experimental validation, microstrip prototypes of a duplexer and a two‐stage quasi‐absorptive BPF that operate in the 1.6–4.4 GHz range are built and tested.
more » « less- Award ID(s):
- 1731956
- PAR ID:
- 10570602
- Publisher / Repository:
- DOI PREFIX: 10.1049
- Date Published:
- Journal Name:
- Electronics Letters
- Volume:
- 54
- Issue:
- 9
- ISSN:
- 0013-5194
- Format(s):
- Medium: X Size: p. 578-580
- Size(s):
- p. 578-580
- Sponsoring Org:
- National Science Foundation
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