CN115425377B - Double-passband balance filter based on loading of ring resonator - Google Patents
Double-passband balance filter based on loading of ring resonator Download PDFInfo
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- CN115425377B CN115425377B CN202211202110.7A CN202211202110A CN115425377B CN 115425377 B CN115425377 B CN 115425377B CN 202211202110 A CN202211202110 A CN 202211202110A CN 115425377 B CN115425377 B CN 115425377B
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01P—WAVEGUIDES; RESONATORS, LINES, OR OTHER DEVICES OF THE WAVEGUIDE TYPE
- H01P1/00—Auxiliary devices
- H01P1/20—Frequency-selective devices, e.g. filters
- H01P1/201—Filters for transverse electromagnetic waves
- H01P1/203—Strip line filters
- H01P1/20309—Strip line filters with dielectric resonator
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01P—WAVEGUIDES; RESONATORS, LINES, OR OTHER DEVICES OF THE WAVEGUIDE TYPE
- H01P5/00—Coupling devices of the waveguide type
- H01P5/12—Coupling devices having more than two ports
- H01P5/16—Conjugate devices, i.e. devices having at least one port decoupled from one other port
- H01P5/18—Conjugate devices, i.e. devices having at least one port decoupled from one other port consisting of two coupled guides, e.g. directional couplers
- H01P5/184—Conjugate devices, i.e. devices having at least one port decoupled from one other port consisting of two coupled guides, e.g. directional couplers the guides being strip lines or microstrips
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01P—WAVEGUIDES; RESONATORS, LINES, OR OTHER DEVICES OF THE WAVEGUIDE TYPE
- H01P7/00—Resonators of the waveguide type
- H01P7/08—Strip line resonators
- H01P7/082—Microstripline resonators
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02D—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN INFORMATION AND COMMUNICATION TECHNOLOGIES [ICT], I.E. INFORMATION AND COMMUNICATION TECHNOLOGIES AIMING AT THE REDUCTION OF THEIR OWN ENERGY USE
- Y02D30/00—Reducing energy consumption in communication networks
- Y02D30/70—Reducing energy consumption in communication networks in wireless communication networks
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Abstract
The utility model provides a dual-passband balance filter based on square ring loading, including medium base plate, one side of medium base plate is equipped with the microstrip line, the microstrip line includes first input port, second input port, first output port, second output port and four mutual gap coupling's ring resonator, first input port, second input port, first output port and second output port are rectangular array and arrange, and ring resonator's both ends form the annular arm of an H shape respectively, and the one end that two annular arms kept away from each other is equipped with the center loading branch respectively. The ring resonator based on square ring loading has multimode characteristics, can be used for designing and realizing two pass bands, is simple and compact in design, has a symmetrical structure, is easy for high-order cascading, realizes flexible regulation and control of the bandwidths of the two pass bands through gaps between ring arms, additional H-shaped coupling lines and coupling blocks, and finally meets the requirement of the two pass bands on external quality factors through a coupling feeder line.
Description
Technical Field
The invention relates to the field of dual-passband filters, in particular to a dual-passband balance filter based on loading of a ring resonator.
Background
With the rapid development of wireless communication technology, frequency spectrum resources are increasingly in shortage, electromagnetic environments are increasingly complex, and application scenes such as mobile communication, radar detection and electronic countermeasure face development demands such as multiband, miniaturization and interference resistance. In communication systems, however, the balanced circuit has stronger environmental noise resistance than the single-ended circuit, and in order to solve the above-mentioned challenges faced in communication systems, in recent years, a miniaturized multi-passband balanced filter having excellent differential performance and noise interference resistance has attracted many scholars' research interests.
Compared with the traditional single-port unbalanced filter, in the design of the balanced filter, not only good differential mode response is realized, but also enough common mode rejection characteristics are needed, and particularly, for the multi-passband balanced filter, flexible control of the center frequency and bandwidth of each passband is also very important.
Disclosure of Invention
The invention aims to provide a double-passband balanced filter based on loading of a ring resonator, which has the characteristics of miniaturization, compact structure and good differential mode transmission and common mode rejection characteristics, and the center frequency and bandwidth of two passbands can be flexibly regulated and controlled.
The technical scheme adopted by the invention for solving the technical problems is as follows: the double-passband balanced filter based on the loading of the ring resonator comprises a dielectric substrate, wherein one side of the dielectric substrate is provided with a microstrip line, the microstrip line comprises a first input port, a second input port, a first output port, a second output port and four ring resonators which are mutually coupled in a clearance mode, the first input port, the second input port, the first output port and the second output port are arranged in a rectangular array, the first input port and the second input port are positioned on the same side of the rectangular array, the first output port and the second output port are positioned on the other side of the rectangular array, the first input port and the second input port and the first output port and the second output port are symmetrically arranged about a central line extending in the X direction of the rectangular array respectively, and the first input port and the first output port and the second input port and the second output port are symmetrically arranged about a central line extending in the Y direction of the rectangular array respectively;
the four ring resonators are sequentially arranged at intervals along the X direction, the middle part of each ring resonator extends along the Y direction, two ends of each ring resonator along the Y direction respectively form an H-shaped ring arm, each ring arm comprises a cross arm extending along the X direction and two longitudinal arms respectively connected with two ends of the cross arm, each longitudinal arm extends along the Y direction and is symmetrically arranged about the Y-direction central line of the cross arm, the two ring arms of the same ring resonator are symmetrically arranged about the central line of the rectangular array extending along the X direction, one ends of the two ring arms, which are far away from each other, are respectively provided with a central loading branch, each central loading branch is positioned between the two ends of the H-shaped ring arms, and each central loading branch is rectangular extending along the Y direction;
the first input port is connected with a first input feeder line and a second input feeder line, the second input port is connected with a third input feeder line and a fourth input feeder line, the first output port is connected with a first output feeder line and a second output feeder line, the second output port is connected with a third output feeder line and a fourth output feeder line, the first input feeder line, the third input feeder line, the first output feeder line and the third output feeder line are respectively and mutually close to one end of an H shape of a self annular arm to realize feeding through gap coupling, and the second input feeder line, the fourth input feeder line, the second output feeder line and the fourth output feeder line are respectively and mutually close to the middle part of a self annular resonator to realize feeding through gap coupling.
Preferably, an H-shaped coupling line is arranged between two adjacent center loading branches of the second ring resonator and the third ring resonator which are arranged at intervals along the X direction, and two ends of the H-shaped coupling line are respectively coupled with the two center loading branches through gaps to realize feeding.
Preferably, coupling blocks are arranged between adjacent annular arms of the first annular resonator, the second annular resonator and the third annular resonator which are arranged at intervals along the X direction, the coupling blocks are rectangular, and the coupling blocks are respectively in gap coupling with the two annular arms to realize feeding.
According to the technical scheme, the invention has the beneficial effects that:
1. the ring resonator based on square ring loading has multimode characteristics, can be used for designing and realizing two pass bands, has simple and compact design, has a symmetrical structure, and is easy for high-order cascading.
2. The center frequencies of two pass bands of the double-pass band balanced filter based on the loading of the ring resonator can be flexibly regulated and controlled through the size of the ring arms and the size of the center loading branch knot, the flexible regulation and control of the bandwidths of the two pass bands are realized through gaps between the ring arms, additional H-shaped coupling lines and coupling blocks, and finally the requirements of the two pass bands on external quality factors are met through the coupling feeder lines.
3. The dual-passband balanced filter based on the loading of the ring resonator has the advantages of miniaturization, compact structure, flexible design, high out-of-band rejection and isolation between passbands of differential mode response, good common mode response rejection characteristics and the like.
Drawings
FIG. 1 is a schematic illustration of the present invention;
FIG. 2 is a schematic diagram of a microstrip line;
FIG. 3 is a schematic diagram of a ring resonator;
fig. 4 is a simulation graph of the present invention.
The marks in the figure: 1. the microstrip line comprises a dielectric substrate, 2, a microstrip line, 3, a first input port, 4, a second input port, 5, a first output port, 6, a second output port, 7, a first input feeder line, 8, a second input feeder line, 9, a fourth input feeder line, 10, a third input feeder line, 11, a first output feeder line, 12, a second output feeder line, 13, a fourth output feeder line, 14, a third output feeder line, 15, a ring arm, 16, a center loading branch, 17, an H-shaped coupling line, 18 and a coupling block.
Detailed Description
Referring to the drawings, the specific embodiments are as follows:
as shown in fig. 1, a dual-passband balanced filter based on loading of a ring resonator includes a dielectric substrate 1, and a microstrip line 2 is disposed on one side of the dielectric substrate 1.
As shown in fig. 2, the microstrip line 2 includes a first input port 3, a second input port 4, a first output port 5, a second output port 6, and four ring resonators that are gap-coupled to each other. The first input port 3, the second input port 4, the first output port 5 and the second output port 6 are arranged in a rectangular array, the first input port 3 and the second input port 4 are positioned on the same side of the rectangular array, and the first output port 5 and the second output port 6 are positioned on the other side of the rectangular array.
As shown in fig. 2, the first input port 3 and the second input port 4, and the first output port 5 and the second output port 6 are respectively arranged symmetrically with respect to the center line extending in the X direction of the rectangular array, and the first input port 3 and the first output port 5, and the second input port 4 and the second output port 6 are respectively arranged symmetrically with respect to the center line extending in the Y direction of the rectangular array, whereby the characteristics of differential mode response and common mode rejection can be well achieved.
As shown in fig. 2-3, four ring resonators are sequentially arranged at intervals along the X direction, the middle part of each ring resonator extends along the Y direction, two ends of each ring resonator along the Y direction respectively form an H-shaped ring arm 15, each ring arm 15 comprises a cross arm extending along the X direction and two longitudinal arms respectively connected with two ends of each cross arm, each longitudinal arm extends along the Y direction and is symmetrically arranged about the Y-direction center line of the cross arm, and each two ring arms 15 of the same ring resonator are symmetrically arranged about the X-direction center line of the rectangular array.
As shown in fig. 2-3, the ends of the two annular arms 15 that are far from each other are respectively provided with a center loading branch 16, the center loading branch 16 is located between the two ends of the H-shape of the annular arms 15, and the shape of the center loading branch 16 is a rectangle extending along the Y-direction.
As shown in fig. 2-3, by adjusting the length of the H-shape of the plurality of ring arms 15 simultaneouslyL 2 The center frequencies of the two pass bands can be controlled simultaneously by adjusting the length of the center loading stub 16 in the Y-directionL 1 And width in X directionW 1 The center frequency of the second passband can be independently controlled. That is, in the case of a dual band filter design, the overall length of the H-shape of the annular arm 15 can be adjusted firstL 2 To determine the center frequency of the first passband and then by adjustingL 1 AndW 1 the center frequency of the second passband is determined, thereby enabling flexible control of the center frequencies of the two passbands.
The double-passband balanced filter is a four-order chebyshev type filter, ring resonators loaded by four square rings are directly coupled through gaps, and the bandwidths of two passbands can be adjusted by adjusting the width of the gaps. In addition, as shown in FIG. 2,an H-shaped coupling line 17 is arranged between two adjacent center loading branches 16 of a second ring resonator and a third ring resonator which are arranged at intervals along the X direction, two ends of the H-shaped coupling line 17 are respectively coupled with the two center loading branches 16 through gaps to realize feeding, and the length of the H-shaped coupling line 17 along the Y direction is adjustedL 3 The bandwidth of the second passband can be independently controlled.
As shown in fig. 2, coupling blocks 18 are arranged between adjacent annular arms 15 of the first annular resonator, the second annular resonator, the third annular resonator and the fourth annular resonator which are arranged at intervals along the X direction, the coupling blocks 18 are rectangular, the coupling blocks 18 are respectively connected with the two annular arms 15 in a gap coupling mode to realize feeding, and the bandwidths of the two pass bands can be finely adjusted by adjusting the length and the width of the coupling blocks 18.
As shown in fig. 2, the first input port 3 is connected with a first input feeder 7 and a second input feeder 8, the second input port 4 is connected with a third input feeder 10 and a fourth input feeder 9, the first output port 5 is connected with a first output feeder 11 and a second output feeder 12, and the second output port 6 is connected with a third output feeder 14 and a fourth output feeder 13. The first input feeder 7, the third input feeder 10, the first output feeder 11 and the third output feeder 14 are respectively and intermittently coupled to one end of the H-shape of the ring-shaped arm 15 near the first input feeder 8, the fourth input feeder 9, the second output feeder 12 and the fourth output feeder 13 are respectively and intermittently coupled to the middle of the ring-shaped resonator near the first input feeder 8, the fourth input feeder 9, the second output feeder 12 and the fourth output feeder 13. By adjusting the lengths of the input and output feed lines, flexible control of the quality factors outside the two pass bands can be achieved.
Fig. 4 illustrates the differential mode frequency simulation response of the dual-passband balanced filter based on loading of the ring resonator of the present invention, resulting in center frequencies of the two passbands of 5.4GHz and 6.3GHz, respectively, and 3-dB relative bandwidths of the two passbands of 2.6% and 1.9%, respectively, yielding two transmission zeros TZ1 and TZ2, respectively, at 4.98GHz and 5.76 GHz.
Claims (3)
1. A dual passband balanced filter based on loading of a ring resonator, characterized by: the micro-strip line structure comprises a medium substrate (1), wherein one side of the medium substrate (1) is provided with a micro-strip line (2), the micro-strip line (2) comprises a first input port (3), a second input port (4), a first output port (5), a second output port (6) and four ring resonators which are mutually coupled in a gap mode, the first input port (3), the second input port (4), the first output port (5) and the second output port (6) are arranged in a rectangular array, the first input port (3) and the second input port (4) are positioned on the same side of the rectangular array, the first output port (5) and the second output port (6) are positioned on the other side of the rectangular array, and the first input port (3) and the second input port (4) and the first output port (5) and the second output port (6) are symmetrically arranged along the central line extending along the X direction of the rectangular array respectively;
the four ring resonators are sequentially arranged at intervals along the X direction, the middle part of each ring resonator extends along the Y direction, two ends of each ring resonator along the Y direction respectively form an H-shaped ring arm (15), each ring arm (15) comprises a cross arm extending along the X direction and two longitudinal arms respectively connected with two ends of the cross arm, each longitudinal arm extends along the Y direction and is symmetrically arranged about the Y-direction central line of the cross arm, the two ring arms (15) of the same ring resonator are symmetrically arranged about the central line of the rectangular array extending along the X direction, one ends, far away from each other, of each ring arm (15) are respectively provided with a central loading branch (16), each central loading branch (16) is positioned between the two ends of the H shape of each ring arm (15), and each central loading branch (16) is rectangular extending along the Y direction;
the first input port (3) is connected with a first input feeder (7) and a second input feeder (8), the second input port (4) is connected with a third input feeder (10) and a fourth input feeder (9), the first output port (5) is connected with a first output feeder (11) and a second output feeder (12), the second output port (6) is connected with a third output feeder (14) and a fourth output feeder (13), the first input feeder (7), the third input feeder (10), the first output feeder (11) and the third output feeder (14) are respectively and mutually connected with one end of an H shape close to a self annular arm (15) to realize feeding through gap coupling, and the second input feeder (8), the fourth input feeder (9), the second output feeder (12) and the fourth output feeder (13) are respectively and mutually connected with the middle part close to the self annular resonator to realize feeding through gap coupling.
2. A dual passband balanced filter based on loading of ring resonators as defined in claim 1 wherein: an H-shaped coupling line (17) is arranged between two adjacent center loading branches (16) of the second ring resonator and the third ring resonator which are arranged at intervals along the X direction, and two ends of the H-shaped coupling line (17) are respectively connected with the two center loading branches (16) in a gap coupling mode to realize feeding.
3. A dual passband balanced filter based on loading of ring resonators as defined in claim 2 wherein: coupling blocks (18) are arranged between adjacent annular arms (15) of the first annular resonator, the second annular resonator and the third annular resonator which are arranged at intervals along the X direction, the coupling blocks (18) are rectangular, and the coupling blocks (18) are respectively coupled with the two annular arms (15) through gaps to realize feeding.
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| CN202211202110.7A CN115425377B (en) | 2022-09-29 | 2022-09-29 | Double-passband balance filter based on loading of ring resonator |
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| CN202211202110.7A CN115425377B (en) | 2022-09-29 | 2022-09-29 | Double-passband balance filter based on loading of ring resonator |
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| CN115425377B true CN115425377B (en) | 2023-09-08 |
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Citations (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2012162972A1 (en) * | 2011-05-27 | 2012-12-06 | 华南理工大学 | Balanced radio frequency electrically tunable band-pass filter with constant absolute bandwidth |
| CN203596401U (en) * | 2013-11-28 | 2014-05-14 | 天津职业技术师范大学 | Ultra wide band band-pass filter of stub loaded rectangular-ring resonator |
| CN104882650A (en) * | 2015-05-26 | 2015-09-02 | 华南理工大学 | Balanced filter adopting coupling branch knot to load resonator |
| CN204651445U (en) * | 2015-05-26 | 2015-09-16 | 华南理工大学 | A kind of many transmission zeros balance filter adopting coupling feed to load |
| CN107887676A (en) * | 2017-10-26 | 2018-04-06 | 上海海事大学 | One kind miniaturization balance double-passband filter |
| WO2018171180A1 (en) * | 2017-03-18 | 2018-09-27 | 深圳市景程信息科技有限公司 | Band-pass filter based on ring resonator |
| CN109193087A (en) * | 2018-09-13 | 2019-01-11 | 南京师范大学 | A kind of novel four function filter-divider of high-performance dual-passband |
| TR201903086A2 (en) * | 2019-02-28 | 2019-06-21 | Nevsehir Haci Bektas Veli Ueniversitesi Rektoerluegue | DOUBLE BAND MICROSTRIP BALLOON BAND PASS FILTER |
| CN112310582A (en) * | 2020-09-23 | 2021-02-02 | 中国人民解放军战略支援部队信息工程大学 | Double-ring loading based three-passband high-temperature superconducting balanced filter |
| CN114597622A (en) * | 2022-02-25 | 2022-06-07 | 南京恒电电子有限公司 | Double-passband balance filtering coupler |
| CN114665244A (en) * | 2022-04-24 | 2022-06-24 | 成都大学 | Microstrip filtering balun based on meander line type ring resonator |
| CN114725635A (en) * | 2022-05-06 | 2022-07-08 | 华东交通大学 | Double-frequency balance filter |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6670866B2 (en) * | 2002-01-09 | 2003-12-30 | Nokia Corporation | Bulk acoustic wave resonator with two piezoelectric layers as balun in filters and duplexers |
-
2022
- 2022-09-29 CN CN202211202110.7A patent/CN115425377B/en active Active
Patent Citations (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2012162972A1 (en) * | 2011-05-27 | 2012-12-06 | 华南理工大学 | Balanced radio frequency electrically tunable band-pass filter with constant absolute bandwidth |
| CN203596401U (en) * | 2013-11-28 | 2014-05-14 | 天津职业技术师范大学 | Ultra wide band band-pass filter of stub loaded rectangular-ring resonator |
| CN104882650A (en) * | 2015-05-26 | 2015-09-02 | 华南理工大学 | Balanced filter adopting coupling branch knot to load resonator |
| CN204651445U (en) * | 2015-05-26 | 2015-09-16 | 华南理工大学 | A kind of many transmission zeros balance filter adopting coupling feed to load |
| WO2018171180A1 (en) * | 2017-03-18 | 2018-09-27 | 深圳市景程信息科技有限公司 | Band-pass filter based on ring resonator |
| CN107887676A (en) * | 2017-10-26 | 2018-04-06 | 上海海事大学 | One kind miniaturization balance double-passband filter |
| CN109193087A (en) * | 2018-09-13 | 2019-01-11 | 南京师范大学 | A kind of novel four function filter-divider of high-performance dual-passband |
| TR201903086A2 (en) * | 2019-02-28 | 2019-06-21 | Nevsehir Haci Bektas Veli Ueniversitesi Rektoerluegue | DOUBLE BAND MICROSTRIP BALLOON BAND PASS FILTER |
| CN112310582A (en) * | 2020-09-23 | 2021-02-02 | 中国人民解放军战略支援部队信息工程大学 | Double-ring loading based three-passband high-temperature superconducting balanced filter |
| CN114597622A (en) * | 2022-02-25 | 2022-06-07 | 南京恒电电子有限公司 | Double-passband balance filtering coupler |
| CN114665244A (en) * | 2022-04-24 | 2022-06-24 | 成都大学 | Microstrip filtering balun based on meander line type ring resonator |
| CN114725635A (en) * | 2022-05-06 | 2022-07-08 | 华东交通大学 | Double-frequency balance filter |
Non-Patent Citations (1)
| Title |
|---|
| 高性能、小型化、多通带微带滤波器研究;罗鸣;《中国优秀硕士学位论文全文数据库（信息科技辑）》;全文 * |
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