Compact Ultra-Wideband Bandpass Filters Achieved by Using a Stub-Loaded Stepped Impedance Resonator
In this paper, we develop a bandpass filter using a stub-loaded stepped impedance resonator (SLSIR) and calculate the even and odd resonant modes of this type of resonator using the input impedance/admittance analysis. In this study, two impedance ratios and two length ratios are operated as the des...
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| Format: | Article |
| Language: | English |
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MDPI AG
2020-01-01
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| Series: | Electronics |
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| Online Access: | https://www.mdpi.com/2079-9292/9/2/209 |
| _version_ | 1811185272776294400 |
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| author | Min-Hang Weng Fu-Zhong Zheng Hong-Zheng Lai Shih-Kun Liu |
| author_facet | Min-Hang Weng Fu-Zhong Zheng Hong-Zheng Lai Shih-Kun Liu |
| author_sort | Min-Hang Weng |
| collection | DOAJ |
| description | In this paper, we develop a bandpass filter using a stub-loaded stepped impedance resonator (SLSIR) and calculate the even and odd resonant modes of this type of resonator using the input impedance/admittance analysis. In this study, two impedance ratios and two length ratios are operated as the design parameters for controlling the resonant modes of the SLSIR. Several resonant mode variation curves operating three resonant modes with different impedance ratios and two length ratios are developed. By tuning the desired impedance ratios and length ratios of the SLSIRs, compact ultra-wideband (UWB) bandpass filters (BPFs) can be achieved. Two examples of the UWB BPFs are designed in this study. The first example is UWB filter with a wide stopband and the second one is dual UWB BPF, namely, with UWB performance and a notch band. The first filter is designed for a UWB response from 3.1 to 5.26 GHz having a stopband from 5.3 to 11 GHz, with an attenuation level better than 18 dB. The second filter example is a dual UWB BPF with the frequency range from 3.1 to 5 GHz and 6 to 10.1 GHz using two sets of the proposed SLSIR. The measured results have insertion loss of less than 1 dB, and return loss greater than 10 dB. Furthermore, the coupling structures and open stub of the SLSIR also provide several transmission zeros at the skirt of the passbands for improving the passband selectivity. |
| first_indexed | 2024-04-11T13:27:44Z |
| format | Article |
| id | doaj.art-5bd42312e08a4086ba3050f08f563089 |
| institution | Directory Open Access Journal |
| issn | 2079-9292 |
| language | English |
| last_indexed | 2024-04-11T13:27:44Z |
| publishDate | 2020-01-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Electronics |
| spelling | doaj.art-5bd42312e08a4086ba3050f08f5630892022-12-22T04:22:00ZengMDPI AGElectronics2079-92922020-01-019220910.3390/electronics9020209electronics9020209Compact Ultra-Wideband Bandpass Filters Achieved by Using a Stub-Loaded Stepped Impedance ResonatorMin-Hang Weng0Fu-Zhong Zheng1Hong-Zheng Lai2Shih-Kun Liu3School of Information Engineering, Putian University, Putian 351100, ChinaInstitute of Photonics Engineering, National Kaohsiung University of Science and Technology, Kaohsiung 80778, TaiwanInstitute of Photonics Engineering, National Kaohsiung University of Science and Technology, Kaohsiung 80778, TaiwanInstitute of Photonics Engineering, National Kaohsiung University of Science and Technology, Kaohsiung 80778, TaiwanIn this paper, we develop a bandpass filter using a stub-loaded stepped impedance resonator (SLSIR) and calculate the even and odd resonant modes of this type of resonator using the input impedance/admittance analysis. In this study, two impedance ratios and two length ratios are operated as the design parameters for controlling the resonant modes of the SLSIR. Several resonant mode variation curves operating three resonant modes with different impedance ratios and two length ratios are developed. By tuning the desired impedance ratios and length ratios of the SLSIRs, compact ultra-wideband (UWB) bandpass filters (BPFs) can be achieved. Two examples of the UWB BPFs are designed in this study. The first example is UWB filter with a wide stopband and the second one is dual UWB BPF, namely, with UWB performance and a notch band. The first filter is designed for a UWB response from 3.1 to 5.26 GHz having a stopband from 5.3 to 11 GHz, with an attenuation level better than 18 dB. The second filter example is a dual UWB BPF with the frequency range from 3.1 to 5 GHz and 6 to 10.1 GHz using two sets of the proposed SLSIR. The measured results have insertion loss of less than 1 dB, and return loss greater than 10 dB. Furthermore, the coupling structures and open stub of the SLSIR also provide several transmission zeros at the skirt of the passbands for improving the passband selectivity.https://www.mdpi.com/2079-9292/9/2/209ultra-widebandbandpass filterstub-loadedstepped impedance resonator |
| spellingShingle | Min-Hang Weng Fu-Zhong Zheng Hong-Zheng Lai Shih-Kun Liu Compact Ultra-Wideband Bandpass Filters Achieved by Using a Stub-Loaded Stepped Impedance Resonator Electronics ultra-wideband bandpass filter stub-loaded stepped impedance resonator |
| title | Compact Ultra-Wideband Bandpass Filters Achieved by Using a Stub-Loaded Stepped Impedance Resonator |
| title_full | Compact Ultra-Wideband Bandpass Filters Achieved by Using a Stub-Loaded Stepped Impedance Resonator |
| title_fullStr | Compact Ultra-Wideband Bandpass Filters Achieved by Using a Stub-Loaded Stepped Impedance Resonator |
| title_full_unstemmed | Compact Ultra-Wideband Bandpass Filters Achieved by Using a Stub-Loaded Stepped Impedance Resonator |
| title_short | Compact Ultra-Wideband Bandpass Filters Achieved by Using a Stub-Loaded Stepped Impedance Resonator |
| title_sort | compact ultra wideband bandpass filters achieved by using a stub loaded stepped impedance resonator |
| topic | ultra-wideband bandpass filter stub-loaded stepped impedance resonator |
| url | https://www.mdpi.com/2079-9292/9/2/209 |
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