CN114725635A - Double-frequency balance filter - Google Patents
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- CN114725635A CN114725635A CN202210486712.3A CN202210486712A CN114725635A CN 114725635 A CN114725635 A CN 114725635A CN 202210486712 A CN202210486712 A CN 202210486712A CN 114725635 A CN114725635 A CN 114725635A
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Abstract
The application provides a double-frequency balanced filter, which comprises a pair of symmetrically arranged input feeder structures, a pair of symmetrically arranged output feeder structures, and a first step impedance resonator and a second step impedance resonator which are symmetrically arranged; wherein the pair of input feed line structures are connected to the first stepped-impedance resonator and the pair of output feed line structures are connected to the second stepped-impedance resonator to provide electromagnetic excitation; the first stepped impedance resonator and the second stepped impedance resonator are both of a symmetrical structure and respectively comprise a stepped impedance body and a first branch node arranged in the center of the stepped impedance body, so that two frequency bands are generated under the action of electromagnetic excitation and are used for common mode frequency suppression of the two frequency bands. The double-frequency balance filter is simple in structure when multi-frequency bands are achieved, each frequency band is flexibly regulated, the design flexibility is enhanced, and the rejection degree of common-mode noise is improved.
Description
Technical Field
The disclosed embodiments of the present application relate to the field of wireless communication technology, and more particularly, to a dual-frequency balanced filter.
Background
Currently, deployment of large-scale wireless communication networks and small-sized wireless communication terminals provide high-quality and intelligent communication services. However, high density wireless communication networks and highly integrated circuits greatly challenge the robustness of communication systems, where electromagnetic interference immunity of the rf front-end device system is most critical. Compared with the traditional non-balanced device for processing single-ended signals, the balanced circuit can effectively inhibit various environmental noises and electronic noises generated by circuit components by using the unique physical topological structure, can solve the problem of electromagnetic interference (EMI) among communication equipment, and greatly improves the signal-to-noise ratio of a receiver and the efficiency of a transmitter.
Therefore, under increasingly complex electromagnetic environments, it is of great significance to design a high-selectivity balanced filter with excellent anti-noise performance. In addition, in order to better meet the requirements of modern wireless communication multiple services, it is important to research and design a balanced filter with multiple operating frequency bands.
Disclosure of Invention
According to an embodiment of the present application, a dual-frequency balanced filter is provided to solve the above problems.
In accordance with aspects of the present application, an exemplary dual frequency balanced filter is disclosed. The exemplary dual-frequency balanced filter includes a pair of input feed line structures and a pair of output feed line structures arranged symmetrically and a first stepped-impedance resonator and a second stepped-impedance resonator arranged symmetrically; wherein the pair of input feed line structures are connected to the first stepped-impedance resonator and the pair of output feed line structures are connected to the second stepped-impedance resonator to provide electromagnetic excitation; the first stepped impedance resonator and the second stepped impedance resonator are both of a symmetrical structure and respectively comprise a stepped impedance body and a first branch node arranged in the center of the stepped impedance body, so that two frequency bands are generated under the action of electromagnetic excitation and are used for common mode frequency suppression of the two frequency bands.
In some embodiments, the dual frequency balanced filter further comprises a first connection line and a second connection line symmetrically arranged and connected with the first impedance-stepping resonator and the second impedance-stepping resonator; the first stepped-impedance resonator and the second stepped-impedance resonator both further comprise a pair of second branches arranged on the stepped-impedance body and spaced from the first branches; wherein the first connection line and the second connection line are used for providing magnetic coupling between the first impedance-stepped resonator and the second impedance-stepped resonator, the two ends of the impedance-stepped body of the first impedance-stepped resonator and the two ends of the impedance-stepped body of the second impedance-stepped resonator and the pair of second branches of the first impedance-stepped resonator and the pair of second branches of the second impedance-stepped resonator are in gap coupling, and the electrical coupling between the first impedance-stepped resonator and the second impedance-stepped resonator is provided, so that two sides of the two frequency bands respectively have a transmission zero point.
In some embodiments, the first stub is a symmetric T-shaped structure, and includes a first sub-stub and a second sub-stub connected between the center of the stepped-impedance body and the center of the first sub-stub, so as to suppress common mode frequencies of the two frequency bands.
In some embodiments, the equivalent impedance of the first sub-branch is the same as the equivalent impedance of the second sub-branch.
In some embodiments, the equivalent impedance of the first sub-branch is the same as the equivalent impedance of the first connection line or the second connection line.
In some embodiments, the impedance step body comprises a first impedance part, two second impedance parts symmetrically arranged, two fourth impedance parts symmetrically arranged, and two fourth impedance parts symmetrically arranged, wherein the center of the first impedance part is the center of the impedance step body, and the first impedance part, the second impedance part, the third impedance part, and the fourth impedance part are connected in sequence from the center of the impedance step body; each second branch in the pair of second branches is connected to the connection position of the first impedance part and the second impedance part.
In some embodiments, the second branch comprises a third sub-branch and a fourth sub-branch, wherein the fourth sub-branch is connected to the third sub-branch, and the equivalent impedance of the fourth sub-branch is different from the equivalent impedance of the third sub-branch; the third impedance part and the fourth impedance part are bent, so that the fourth impedance part and the fourth sub-branch are located on the same straight line and used for the gap coupling together.
In some embodiments, the equivalent impedance of the third sub-branch is the same as the equivalent impedance of the second impedance section; the equivalent impedance of the fourth sub-branch is the same as the equivalent impedance of the fourth impedance part.
In some embodiments, the pair of input feed line structures comprises first and second symmetrically arranged input feed lines, and the pair of output feed line structures comprises first and second symmetrically arranged output feed lines; wherein the first input feed line and the first output feed line correspond to the first connecting line, and the second input feed line and the second output feed line correspond to the second connecting line.
In some embodiments, the first input feed line, the first output feed line and the first connecting line are collinear; the second input feed line, the second output feed line and the second connecting line are located on another straight line.
The beneficial effect of this application has: the first step impedance resonator and the second step impedance resonator both comprise step impedance bodies to generate two frequency bands under the action of electromagnetic excitation, the multiband double-frequency balance filter with a simple structure is realized, each frequency band can be flexibly regulated and controlled, the design flexibility is enhanced, and the first step impedance resonator and the second step impedance resonator both comprise first branches arranged at the centers of the step impedance bodies to be used for common-mode frequency suppression of the two frequency bands, improve the suppression degree of common-mode noise and realize the multiband double-frequency balance filter with good performance.
These and other objects of the present application will no doubt become obvious to those of ordinary skill in the art after having read the following detailed description of the preferred embodiments, which are illustrated in the various drawing figures and drawings.
Drawings
Fig. 1 is a schematic structural diagram of a dual-frequency balanced filter according to an embodiment of the present application;
fig. 2 is a scattering parameter graph of a dual-frequency balanced filter according to an embodiment of the application.
Detailed Description
Certain terms are used throughout the description and claims to refer to particular components. As one skilled in the art can appreciate, electronic device manufacturers may refer to a component by different names. This document does not intend to distinguish between components that differ in name but not function. In the following specification and claims, the word "comprise" is an open-ended term of art, and thus should be interpreted to mean "including, but not limited to …". Additionally, the term "coupled" is intended to mean either an indirect electrical connection or a direct electrical connection. Thus, when one device is coupled to another device, that connection may be through a direct electrical connection or through an indirect electrical connection via other devices and connections.
Fig. 1 is a schematic structural diagram of a dual-frequency balanced filter according to an embodiment of the present application. The dual frequency balanced filter 100 includes a pair of input feed line structures 110 and a pair of output feed line structures 120 symmetrically disposed and a first stepped-impedance resonator 130 and a second stepped-impedance resonator 140 symmetrically disposed.
The symmetrical arrangement of the pair of input feed line structures 110 and the pair of output feed line structures 120 and the first stepped-impedance resonator 130 and the second stepped-impedance resonator 140 may be arranged according to actual circuit design considerations. In the present embodiment, the pair of input feed line structures 110 and the pair of output feed line structures 120, and the first stepped impedance resonator 130 and the second stepped impedance resonator 140 are disposed in vertical symmetry, i.e., the symmetry direction is a vertical direction. In other embodiments, the pair of input feed line structures 110 and the pair of output feed line structures 120 and the first stepped-impedance resonator 130 and the second stepped-impedance resonator 140 may also be symmetrically disposed about a tilt line.
Wherein a pair of input feed line structures 110 are connected to a first stepped-impedance resonator 130 and a pair of output feed line structures 120 are connected to a second stepped-impedance resonator 140 to provide electromagnetic excitation.
The first impedance step-up resonator 130 and the second impedance step-up resonator 140 are both symmetrical structures, and each of the first impedance step-up resonator and the second impedance step-up resonator includes a impedance step-up body a and a first branch b disposed at the center of the impedance step-up body a, so as to generate two frequency bands under the action of electromagnetic excitation, and to suppress common mode frequencies of the two frequency bands.
The symmetrical direction of the symmetrical structure may be perpendicular to the symmetrical direction of the first and second stepped impedance resonators 130 and 140 which are symmetrically disposed. For example, if the symmetry direction of the first stepped impedance resonator 130 and the second stepped impedance resonator 140 which are symmetrically arranged is a vertical direction, the symmetry direction of the symmetrical structure is a horizontal direction, i.e., the symmetrical structure is horizontally symmetrically arranged.
The stepped impedance body a is a symmetrical half-wavelength resonator, and under electromagnetic excitation, the stepped impedance bodies a of the first and second stepped impedance resonators 130 and 140 can generate 2 frequencies, each frequency forming one frequency band, and the center frequencies of the two frequency bands are sequentially increased. The first branch b is arranged at the center of the impedance step body a and is used for common mode frequency rejection of two frequency bands.
In this embodiment, the first stepped-impedance resonator 130 and the second stepped-impedance resonator 140 each include a stepped-impedance body a to generate two frequency bands under the action of electromagnetic excitation, so as to implement the multiband dual-band balanced filter 100 with a simple structure, flexibly regulate and control each frequency band, and enhance design flexibility, and the first stepped-impedance resonator 130 and the second stepped-impedance resonator 140 each include a first stub b disposed at the center of the stepped-impedance body a to suppress common mode frequencies of the two frequency bands, thereby improving the degree of suppression of common mode noise, and implementing the multiband dual-band balanced filter 100 with good performance.
As described above, the stepped-impedance body a of the first stepped-impedance resonator 130 and the second stepped-impedance resonator 140 generates two frequency bands by the electromagnetic excitation, and the first stub b of the first stepped-impedance resonator 130 and the second stepped-impedance resonator 140 provided at the center of the stepped-impedance body a is used for common mode frequency suppression of the two frequency bands. In some embodiments, each of the first and second stepped- impedance resonators 130 and 140 further includes a pair of second branches c disposed on the stepped-impedance body a and spaced apart from the first branches b; the dual frequency balanced filter further includes a first connection line 150 and a second connection line 160, which are symmetrically disposed, and are connected to the first stepped impedance resonator 130 and the second stepped impedance resonator 140.
The first connection line 150 and the second connection line 160 are used for providing magnetic coupling between the first impedance-stepped resonator 130 and the second impedance-stepped resonator 140, and the two ends of the impedance-stepped body a of the first impedance-stepped resonator 130 and the two ends of the impedance-stepped body a of the second impedance-stepped resonator 140 and the pair of second branches c of the first impedance-stepped resonator 130 and the pair of second branches c of the second impedance-stepped resonator 140 are coupled in a gap, so as to provide electrical coupling between the first impedance-stepped resonator 130 and the second impedance-stepped resonator 140, so that two sides of the two frequency bands respectively have a transmission zero.
The first branch b is disposed at the center of the impedance step body a, and the pair of second branches c are disposed at intervals from the first branch b, so that the pair of second branches c are disposed at two opposite ends of the impedance step body a and are symmetrically disposed. The symmetry direction of the pair of second branches c is the same as the symmetry direction of the impedance step body a.
The two ends of the impedance step body a of the first impedance step resonator 130 and the two ends of the impedance step body a of the second impedance step resonator 140, and the pair of second branches c of the first impedance step resonator 130 and the pair of second branches c of the second impedance step resonator 140 are coupled by the gap, that is, the gap between the two ends of the impedance step body a of the first impedance step resonator 130 and the two ends of the impedance step body a of the second impedance step resonator 140 is the same as the gap between the pair of second branches c of the first impedance step resonator 130 and the pair of second branches c of the second impedance step resonator 140, so as to realize the gap coupling together.
Due to the coupling and the electric coupling of the gap, two sides of two frequency bands generated by the step impedance body a are respectively provided with a transmission zero point, so that the selectivity of the frequency bands is improved, and the performance of the double-frequency balance filter is improved.
The symmetrical direction of the first and second connection lines 150 and 160, which are symmetrically disposed, may be a horizontal direction, which is the same as the symmetrical direction of the stepped impedance body a. Meanwhile, the first connection line 150 and the second connection line 160 are also vertically symmetrical, i.e., the symmetrical direction of the first connection line 150 and the second connection line 160 is a vertical direction.
As described above, the first stub b of the first and second transimpedance resonators 130 and 140 provided at the center of the transimpedance main body a is used for common mode frequency rejection in two frequency bands. In some embodiments, the first branch b is a symmetrical T-shaped structure, and includes a first sub-branch b1 and a second sub-branch b2 connected between the center of the impedance step-change body a and the center of the first sub-branch b1 for common mode frequency rejection of two bands.
The symmetrical direction of the first stub b is the same as the symmetrical direction of the first stepped impedance resonator 130 or the second stepped impedance resonator 140, that is, the symmetrical direction of the symmetrical structure described above. For example, the symmetry direction of the first stepped impedance resonator 130 or the second stepped impedance resonator 140 is a horizontal direction, and the symmetry direction of the first branch b is also a horizontal direction. For another example, the first stepped impedance resonator 130 or the second stepped impedance resonator 140 has a tilted line as a symmetric direction, and the first branch b has a tilted line as a symmetric direction, that is, both are symmetric about the tilted line.
In some examples, the equivalent impedance of the first sub-branch b1 is the same as the equivalent impedance of the second sub-branch b 2. The equivalent impedance of the first sub-branch b1 is the same as that of the second sub-branch b2, i.e., the physical widths of the first sub-branch b1 are the same as that of the second sub-branch b 2.
In some embodiments, the equivalent impedance of the first sub-branch b1 is the same as the equivalent impedance of the first connection line 150 or the second connection line 160. The first sub-branch b1 has the same equivalent impedance as the first connection line 150 or the second connection line 160, that is, the first sub-branch b1 has the same physical width as the first connection line 150 or the second connection line 160, wherein the first connection line 150 and the second connection line 160 are symmetrically disposed, and the first connection line 150 has the same equivalent impedance as the second connection line 160, that is, the same physical width.
As described above, the impedance step body a is a symmetric half-wavelength resonator, and in some embodiments, the impedance step body a includes the first impedance portion a1, two second impedance portions a2 symmetrically arranged, two third impedance portions a3 symmetrically arranged, and two fourth impedance portions a4 symmetrically arranged, wherein the center of the first impedance portion a1 is the center of the impedance step body a, and the first impedance portion a1, the second impedance portion a2, the third impedance portion a3, and the fourth impedance portion a4 are sequentially connected from the center of the impedance step body a; each of the pair of second branches c is connected to a connection of the first impedance part a1 and the second impedance part a 2.
The equivalent impedances of the first impedance part a1, the second impedance part a2, the third impedance part a3 and the fourth impedance part a4 are different and are sequentially connected from the center of the stepped impedance body a, that is, the stepped impedance body a is a four-stage step, which is beneficial to adjusting the center frequencies of two frequency bands and improving the flexibility of designing the dual-frequency band. In the present embodiment, the equivalent impedances of the first impedance portion a1, the second impedance portion a2, the third impedance portion a3 and the fourth impedance portion a4 sequentially decrease, that is, the physical widths of the first impedance portion a1, the second impedance portion a2, the third impedance portion a3 and the fourth impedance portion a4 sequentially increase.
As described above, the pair of second branches c are spaced apart from the first branch b, and each of the pair of second branches c is connected to the connection between the first impedance part a1 and the second impedance part a2, and in some embodiments, the second branches c include a third sub-branch c1 and a fourth sub-branch c2, wherein the fourth sub-branch c2 is connected to the third sub-branch c1, and the equivalent impedance of the fourth sub-branch c2 is different from the equivalent impedance of the third sub-branch c 1; the third impedance portion a3 and the fourth impedance portion a4 are bent such that the fourth impedance portion a4 and the fourth sub-branch c2 are located on the same straight line to be commonly used for slot coupling.
The equivalent impedance of the fourth sub-branch c2 is different from the equivalent impedance of the third sub-branch c1, i.e. the physical width of the fourth sub-branch c2 is different from that of the third sub-branch c 1.
The third impedance part a3 and the fourth impedance part a4 are subjected to bending processing, that is, the third impedance part a3 is bent once, so that the third impedance part a3 is disposed perpendicular to the second impedance part a2, and the fourth impedance part a4 is bent once, so that the fourth impedance part a4 is disposed perpendicular to the third impedance part a3, and therefore, the fourth impedance part a4 and the fourth sub-branch c2 are positioned on the same straight line, and the fourth impedance part a4 and the fourth sub-branch c2 of the first step impedance resonator 130 and the second step impedance resonator 140 are commonly used for slot coupling, thereby improving the performance of each frequency band of the dual band balanced filter 100, and achieving miniaturization and reducing the manufacturing cost.
Note that the bending of the third impedance portion a3 and the fourth impedance portion a4 once means that the third impedance portion a3 and the fourth impedance portion a4 are bent 90 degrees once, so that the third impedance portion a3 is disposed perpendicular to the second impedance portion a2, and the fourth impedance portion a4 is disposed perpendicular to the third impedance portion a 3.
In some examples, the equivalent impedance of the third sub-branch c1 is the same as the equivalent impedance of the second impedance section a 2; the equivalent impedance of the fourth sub-branch c2 is the same as the equivalent impedance of the fourth impedance part a 4. The equivalent impedance of the third sub-branch c1 is the same as that of the second impedance part a2, the equivalent impedance of the fourth sub-branch c2 is the same as that of the fourth impedance part a4, that is, the physical widths of the third sub-branch c1 and the second impedance part a2 are the same, and the equivalent impedance of the fourth sub-branch c2 is the same as that of the fourth impedance part a 4.
As described above, the pair of input feed line structures 110 and the pair of output feed line structures 120 are symmetrically disposed, for example, vertically symmetrically disposed, and in this case, in some embodiments, the pair of input feed line structures 110 are also symmetrically disposed, and the pair of output feed line structures 120 are also symmetrically disposed. For example, the pair of input feeder structures 110 are horizontally symmetrical, and similarly, since the pair of input feeder structures 110 and the pair of output feeder structures 120 are vertically symmetrical, the pair of input feeder structures 110 are also horizontally symmetrical.
Specifically, in some embodiments, the pair of input feed line structures 110 includes a first input feed line 111 and a second input feed line 112 that are symmetrically disposed, and the pair of output feed line structures 120 includes a first output feed line 121 and a second output feed line 122 that are symmetrically disposed, wherein the first input feed line 111 and the first output feed line 121 correspond to the first connecting line 150, and the second input feed line 112 and the second output feed line 122 correspond to the second connecting line 160. In the present embodiment, the symmetrical arrangement of the first and second input feed lines 111 and 112 and the first and second output feed lines 121 and 122 is arranged symmetrically up and down in the horizontal direction, but the present application is not limited thereto, and it may be arranged according to actual circuit design considerations.
One end of each of the first input feed line 111, the second input feed line 112, the first output feed line 121, and the second output feed line 122 is used to implement tap coupling, and the other end is an input port/output port. The other ends of the first input feeder line 111 and the second input feeder line 112 serve as input ports to which electromagnetic signals are fed, and the other ends of the first output feeder line 121 and the second output feeder line 122 serve as output ports from which electromagnetic signals are fed. Note that the arrangement of the input port and the output port is merely illustrative, and the input port and the output port may be reversed.
The first input feed line 111 and the first output feed line 121 correspond to a first connection line 150, and the second input feed line 112 and the second output feed line 122 correspond to a second connection line 160, facilitating magnetic coupling between the first and second stepped- impedance resonators 130 and 140 using the first and second connection lines 150 and 160.
The equivalent impedance of the first input feed line 111, the second input feed line 112, the first output feed line 121, and the second output feed line 122 is 50 ohms.
As described above, the first input feeder line 111 and the first output feeder line 121 correspond to the first connection line 150, the second input feeder line 112 and the second output feeder line 122 correspond to the second connection line 160, and in some embodiments, the first input feeder line 111, the first output feeder line 121, and the first connection line 150 are located on the same straight line; the second input feed line 112, the second output feed line 122 and the second connection line 160 are located on another straight line.
The first input feed line 111, the first output feed line 121 and the first connecting line 150 are located on the same straight line, and the second input feed line 112, the second output feed line 122 and the second connecting line 160 are located on another straight line, which further facilitates the magnetic coupling between the first stepped-impedance resonator 130 and the second stepped-impedance resonator 140 using the first connecting line 150 and the second connecting line 160.
Further, in some embodiments, the dual frequency balanced filter 100 includes a pair of input feed line structures 110 and a pair of output feed line structures 120 symmetrically disposed and a first stepped-impedance resonator 130 and a second stepped-impedance resonator 140 symmetrically disposed. That is, a dielectric substrate is used to fabricate the dual-band balanced filter 100. The dielectric substrate can be a high-temperature superconducting dielectric substrate and is made of magnesium oxide, the upper surface and the lower surface of the high-temperature superconducting dielectric substrate are made of yttrium barium copper oxide superconducting films, the dielectric constant of the high-temperature superconducting dielectric substrate is 9.78, the thickness of the high-temperature superconducting dielectric substrate is 0.5mm, at the moment, the dual-frequency balance filter 100 is small in loss and high in quality factor, and therefore the dual-frequency balance filter 100 is better in effect, stable to use and long in service time when being applied to the dual-frequency balance filter 100 and the like. Of course, it is within the understanding of those skilled in the art that the dielectric substrate may also be made of dielectric substrates with other parameters to make the dual-band balanced filter 100, and is not limited herein.
Fig. 2 is a scattering parameter graph of a dual-frequency balanced filter according to an embodiment of the present application. For the dual-band balanced filter 100 of the above embodiment, when a dielectric substrate is used for manufacturing, the center frequencies of the two frequency bands are 1.48GHz and 4.25GHz, respectively, the insertion loss in the frequency band is less than 0.1dB, the return loss is greater than 20dB, the common mode insertion loss is greater than 25dB, that is, the common mode noise rejection is better than 25dB, and two sides of the two frequency bands respectively have a transmission zero, so as to improve the selectivity of the frequency bands.
It will be apparent to those skilled in the art that many modifications and variations can be made in the devices and methods while maintaining the teachings of the present application. Accordingly, the above disclosure should be viewed as limited only by the scope of the appended claims.
Claims (10)
1. A dual-frequency balanced filter, comprising:
the feed line structure comprises a pair of symmetrically arranged input feed line structures, a pair of symmetrically arranged output feed line structures, a first step impedance resonator and a second step impedance resonator, wherein the first step impedance resonator and the second step impedance resonator are symmetrically arranged;
wherein the pair of input feed line structures are connected to the first stepped-impedance resonator and the pair of output feed line structures are connected to the second stepped-impedance resonator to provide electromagnetic excitation;
the first stepped impedance resonator and the second stepped impedance resonator are both of a symmetrical structure and respectively comprise a stepped impedance body and a first branch node arranged in the center of the stepped impedance body, so that two frequency bands are generated under the action of electromagnetic excitation and are used for common mode frequency suppression of the two frequency bands.
2. The dual frequency balanced filter of claim 1, further comprising:
the first connecting wire and the second connecting wire are symmetrically arranged and are connected with the first step impedance resonator and the second step impedance resonator;
the first stepped-impedance resonator and the second stepped-impedance resonator both further comprise a pair of second branches arranged on the stepped-impedance body and spaced from the first branches;
wherein the first connection line and the second connection line are used for providing magnetic coupling between the first impedance-stepped resonator and the second impedance-stepped resonator, the two ends of the impedance-stepped body of the first impedance-stepped resonator and the two ends of the impedance-stepped body of the second impedance-stepped resonator and the pair of second branches of the first impedance-stepped resonator and the pair of second branches of the second impedance-stepped resonator are in gap coupling, and the electrical coupling between the first impedance-stepped resonator and the second impedance-stepped resonator is provided, so that two sides of the two frequency bands respectively have a transmission zero point.
3. The dual-band balanced filter of claim 2, wherein the first stub is a symmetrical T-shaped structure comprising a first sub-stub and a second sub-stub connected between the center of the stepped-impedance body and the center of the first sub-stub for common-mode frequency rejection of the two bands.
4. The dual frequency balanced filter of claim 3,
the equivalent impedance of the first sub-branch is the same as the equivalent impedance of the second sub-branch.
5. The dual frequency balanced filter of claim 3,
the equivalent impedance of the first sub-branch is the same as the equivalent impedance of the first connecting line or the second connecting line.
6. The dual-frequency balanced filter according to claim 2, wherein the stepped impedance body comprises a first impedance portion, two second impedance portions symmetrically arranged, two fourth impedance portions symmetrically arranged, and two fourth impedance portions symmetrically arranged, wherein a center of the first impedance portion is a center of the stepped impedance body, and the first impedance portion, the second impedance portion, the third impedance portion, and the fourth impedance portions are connected in order from the center of the stepped impedance body;
each second branch in the pair of second branches is connected to the connection position of the first impedance part and the second impedance part.
7. The dual frequency balanced filter of claim 6,
the second branch node comprises a third sub branch node and a fourth sub branch node, wherein the fourth sub branch node is connected with the third sub branch node, and the equivalent impedance of the fourth sub branch node is different from that of the third sub branch node;
the third impedance part and the fourth impedance part are bent, so that the fourth impedance part and the fourth sub-branch are located on the same straight line and used for the gap coupling together.
8. The dual frequency balanced filter of claim 7,
the equivalent impedance of the third sub-branch is the same as that of the second impedance part;
the equivalent impedance of the fourth sub-branch is the same as the equivalent impedance of the fourth impedance part.
9. The dual frequency balanced filter according to any one of claims 1-8,
the pair of input feeder structures comprises a first input feeder and a second input feeder which are symmetrically arranged, and the pair of output feeder structures comprises a first output feeder and a second output feeder which are symmetrically arranged;
wherein the first input feed line and the first output feed line correspond to the first connecting line, and the second input feed line and the second output feed line correspond to the second connecting line.
10. The dual frequency balanced filter of claim 9,
the first input feeder line, the first output feeder line and the first connecting line are positioned on the same straight line;
the second input feed line, the second output feed line and the second connecting line are located on another straight line.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210486712.3A CN114725635B (en) | 2022-05-06 | 2022-05-06 | Dual-frequency balance filter |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210486712.3A CN114725635B (en) | 2022-05-06 | 2022-05-06 | Dual-frequency balance filter |
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| Publication Number | Publication Date |
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| CN114725635A true CN114725635A (en) | 2022-07-08 |
| CN114725635B CN114725635B (en) | 2024-01-30 |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115149229A (en) * | 2022-07-15 | 2022-10-04 | 华东交通大学 | Balance filter |
| CN115425377A (en) * | 2022-09-29 | 2022-12-02 | 河南科技大学 | Double-passband balance filter based on square ring loading |
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| JP2010081292A (en) * | 2008-09-26 | 2010-04-08 | Kyocera Corp | Branching filter, and wireless communication mudule and wireless communication device using the same |
| WO2015003652A1 (en) * | 2013-07-12 | 2015-01-15 | 中兴通讯股份有限公司 | Dbr filter and dbr duplexer |
| CN109524749A (en) * | 2018-11-23 | 2019-03-26 | 西安交通大学 | A kind of double-passband filter with trap characteristic |
| CN112103610A (en) * | 2020-10-22 | 2020-12-18 | 南通大学 | Balanced multimode band-pass filter |
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| US20040041649A1 (en) * | 2002-09-03 | 2004-03-04 | Broadcom Corporation | Compact balun with rejection filter for 802.11a and 802.11b simultaneous operation |
| JP2010081292A (en) * | 2008-09-26 | 2010-04-08 | Kyocera Corp | Branching filter, and wireless communication mudule and wireless communication device using the same |
| WO2015003652A1 (en) * | 2013-07-12 | 2015-01-15 | 中兴通讯股份有限公司 | Dbr filter and dbr duplexer |
| CN109524749A (en) * | 2018-11-23 | 2019-03-26 | 西安交通大学 | A kind of double-passband filter with trap characteristic |
| CN112103610A (en) * | 2020-10-22 | 2020-12-18 | 南通大学 | Balanced multimode band-pass filter |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115149229A (en) * | 2022-07-15 | 2022-10-04 | 华东交通大学 | Balance filter |
| CN115149229B (en) * | 2022-07-15 | 2024-02-20 | 华东交通大学 | Balanced filter |
| CN115425377A (en) * | 2022-09-29 | 2022-12-02 | 河南科技大学 | Double-passband balance filter based on square ring loading |
| CN115425377B (en) * | 2022-09-29 | 2023-09-08 | 河南科技大学 | Double-passband balance filter based on loading of ring resonator |
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| CN114725635B (en) | 2024-01-30 |
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