CN220797045U - Topological structure of dual-passband filter with small center frequency ratio and filter - Google Patents
Topological structure of dual-passband filter with small center frequency ratio and filter Download PDFInfo
- Publication number
- CN220797045U CN220797045U CN202322303411.5U CN202322303411U CN220797045U CN 220797045 U CN220797045 U CN 220797045U CN 202322303411 U CN202322303411 U CN 202322303411U CN 220797045 U CN220797045 U CN 220797045U
- Authority
- CN
- China
- Prior art keywords
- parallel
- filter
- lines
- passband
- line
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- 230000005540 biological transmission Effects 0.000 claims description 29
- 230000009977 dual effect Effects 0.000 claims description 5
- 238000003780 insertion Methods 0.000 description 8
- 230000037431 insertion Effects 0.000 description 8
- 238000004088 simulation Methods 0.000 description 7
- 238000002955 isolation Methods 0.000 description 5
- 238000004891 communication Methods 0.000 description 3
- 238000013461 design Methods 0.000 description 3
- 230000009286 beneficial effect Effects 0.000 description 1
- 239000000470 constituent Substances 0.000 description 1
- 230000008094 contradictory effect Effects 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000010354 integration Effects 0.000 description 1
- 238000011160 research Methods 0.000 description 1
Landscapes
- Control Of Motors That Do Not Use Commutators (AREA)
Abstract
The utility model discloses a topological structure of a dual-passband filter with a small center frequency ratio and the filter, wherein the topological structure comprises a microstrip line, one end of the microstrip line is symmetrically connected with one end of a first parallel five line and one end of a second parallel five line, and the other end of the microstrip line is symmetrically connected with one end of a first short circuit branch and one end of a second short circuit branch; the other end of the first parallel five wires is connected with the input end, the other end of the second parallel five wires is connected with the output end, and the other end of the first short circuit branch and the other end of the second short circuit branch are respectively grounded. The utility model solves the problem that the ratio of the center frequencies of two channels of the existing dual-passband filter is large.
Description
Technical Field
The utility model relates to the technical field of filters, in particular to a topological structure of a dual-passband filter with a small center frequency ratio and the filter.
Background
With the rapid development of modern wireless communication technology, the radio frequency receiving front end needs to be compatible with different communication systems and provide richer services to meet the increasing digital application demands of people. Under the background, the microstrip dual-passband filter with low cost, small volume, low profile, light weight and easy integration attracts attention of vast students and engineers and is subjected to intensive research. However, the microstrip dual-passband filter reported at present has the problems of narrow bandwidth, large insertion loss, poor isolation, large size, large center frequency ratio of two channels and the like, and seriously affects the use of the microstrip dual-passband filter in a modern wireless communication system.
Disclosure of Invention
The utility model mainly aims to provide a topological structure of a dual-passband filter with a small center frequency ratio and a filter, and aims to solve the problem that the center frequency ratio of two channels of the existing dual-passband filter is large.
In order to achieve the above-mentioned purpose, the present utility model proposes a topology structure of a dual-passband filter with a small center frequency ratio, which includes a microstrip line, wherein one end of the microstrip line is symmetrically connected with one end of a first parallel five line and one end of a second parallel five line, and the other end of the microstrip line is symmetrically connected with one end of a first short-circuit branch and one end of a second short-circuit branch; the other end of the first parallel five wires is connected with the input end, the other end of the second parallel five wires is connected with the output end, and the other end of the first short circuit branch and the other end of the second short circuit branch are respectively grounded.
Optionally, the electrical length of the microstrip line, the electrical length of the first parallel five line, the electrical length of the second parallel five line, the electrical length of the first short circuit branch and the electrical length of the second short circuit branch are all equal.
Optionally, the electrical length of the microstrip line, the electrical length of the first parallel five line, the electrical length of the second parallel five line, the electrical length of the first short circuit branch and the electrical length of the second short circuit branch are all set to be a quarter wavelength corresponding to the center frequency of the intermediate stop band of the two pass bands.
Optionally, the first parallel five lines and the second parallel five lines respectively include five transmission lines arranged in parallel with each other.
Optionally, the parameters of the topology structure include a width of the transmission line, a spacing between adjacent transmission lines, a width of the microstrip line, and a width of the first and second short circuit branches.
In order to achieve the above objective, the present utility model further provides a filter, which includes any one of the above topological structure designed filters.
Optionally, the filter further includes a circuit board, where the dielectric constant of the circuit board is 3.38, the dielectric loss is 0.0022, and the thickness is 0.813mm.
Optionally, the circuit board size of the filter is 25.4mm by 12.0mm.
Optionally, the lengths of the first parallel five lines and the second parallel five lines are set to 9.7mm, the lengths of the microstrip lines are set to 10.2mm, and the lengths of the first short circuit branches and the second short circuit branches are set to 10.35mm; the transmission line width of the first parallel five lines and the second parallel five lines is set to be 0.1mm, the transmission line distance of the first parallel five lines and the second parallel five lines is set to be 0.06mm, the width of the microstrip line is set to be 2.2mm, and the width of the first short circuit branch knot and the second short circuit branch knot is set to be 2.0mm.
The utility model has the beneficial effects that: the topological structure of the existing filter is improved, the existing filter comprises a microstrip line, one end of the microstrip line is symmetrically connected with one end of a first parallel five line and one end of a second parallel five line, and the other end of the microstrip line is symmetrically connected with one end of a first short circuit branch and one end of a second short circuit branch; the other end of the first parallel five wires is connected with the input end, the other end of the second parallel five wires is connected with the output end, and the other end of the first short circuit branch and the other end of the second short circuit branch are respectively grounded. The filter designed based on the topological structure has the advantages of wide bandwidth, small insertion loss, high isolation, small size and small passband center frequency ratio.
Drawings
In order to more clearly illustrate the embodiments of the present utility model or the technical solutions in the prior art, the drawings that are required in the embodiments or the description of the prior art will be briefly described, and it is obvious that the drawings in the following description are only some embodiments of the present utility model, and other drawings may be obtained according to the structures shown in these drawings without inventive effort for a person skilled in the art.
FIG. 1 is a topology of a filter of the present utility model;
FIG. 2 is a topology-based filter layout of the present utility model;
FIG. 3 shows the simulation S-parameters of the filter according to the present utility model P Is a variation graph of (2);
FIG. 4 shows the simulation S-parameters of the filter according to the present utility model as w P Is a variation graph of (2);
FIG. 5 shows the simulation S-parameters of the filter according to the present utility model as w varies 1 Is a variation graph of (2);
FIG. 6 shows the simulation S-parameters of the filter according to the present utility model as w varies 2 Is a variation graph of (2);
FIG. 7 is a schematic diagram of the simulation result of the S parameter of the filter according to the present utility model;
the achievement of the objects, functional features and advantages of the present utility model will be further described with reference to the accompanying drawings, in conjunction with the embodiments.
Detailed Description
The following description of the embodiments of the present utility model will be made clearly and fully with reference to the accompanying drawings, in which it is evident that the embodiments described are only some, but not all embodiments of the utility model. All other embodiments, which can be made by those skilled in the art based on the embodiments of the utility model without making any inventive effort, are intended to be within the scope of the utility model.
It should be noted that, if directional indications (such as up, down, left, right, front, and rear … …) are included in the embodiments of the present utility model, the directional indications are merely used to explain the relative positional relationship, movement conditions, etc. between the components in a specific posture (as shown in the drawings), and if the specific posture is changed, the directional indications are correspondingly changed.
In addition, if there is a description of "first", "second", etc. in the embodiments of the present utility model, the description of "first", "second", etc. is for descriptive purposes only and is not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include at least one such feature. In addition, if the meaning of "and/or" is presented throughout this document, it is intended to include three schemes in parallel, taking "a and/or B" as an example, including a scheme, or B scheme, or a scheme where a and B meet simultaneously. In addition, the technical solutions of the embodiments may be combined with each other, but it is necessary to base that the technical solutions can be realized by those skilled in the art, and when the technical solutions are contradictory or cannot be realized, the combination of the technical solutions should be considered to be absent and not within the scope of protection claimed in the present utility model.
An embodiment of the present utility model proposes a topology structure of a dual-passband filter with a small center frequency ratio, referring to fig. 1, the topology structure includes a microstrip line, one end of the microstrip line is symmetrically connected with one end of a first parallel five line and one end of a second parallel five line, and the other end of the microstrip line is symmetrically connected with one end of a first short-circuit branch and one end of a second short-circuit branch; the other end of the first parallel five wires is connected with the input end, the other end of the second parallel five wires is connected with the output end, and the other end of the first short circuit branch and the other end of the second short circuit branch are respectively grounded. In this embodiment, as shown in fig. 1, the topology structure is set in a symmetrical structure, the first parallel five lines and the second parallel five lines are identical, and the first parallel five lines and the second parallel five lines are symmetrically arranged based on the microstrip lines, the first short-circuit branch and the second short-circuit branch are identical, and the first short-circuit branch and the second short-circuit branch are symmetrically arranged based on the microstrip lines, thereby forming the topology structure of the dual-passband filter.
Further, the electrical length of the microstrip line, the electrical length of the first parallel five line, the electrical length of the second parallel five line, the electrical length of the first short circuit branch and the electrical length of the second short circuit branch are equal. Specifically, the electrical length of the microstrip line, the electrical length of the first parallel five lines, the electrical length of the second parallel five lines, the electrical length of the first short circuit branch and the electrical length of the second short circuit branch are respectively set to be a quarter wavelength corresponding to the center frequency of the intermediate stop band of the two pass bands.
Further, the first parallel five lines and the second parallel five lines respectively include five transmission lines which are arranged in parallel with each other. The common knowledge of microwaves shows that the values of the physical length of the parallel five lines, the physical length of the microstrip line and the physical length of the short circuit branch can be changed synchronously and equivalently, and the working frequency ranges of the two pass bands can be adjusted in an inverse proportion and linear mode. In this embodiment, in order to ensure that the filter designed based on the topology structure has the advantages of wide bandwidth, small insertion loss, high isolation, small size, and small passband center frequency ratio, the design parameters of the topology structure of this embodiment include the width of the transmission line, the distance between adjacent transmission lines, the width of the microstrip line, and the widths of the first short circuit branch and the second short circuit branch. The width of the microstrip line is slightly greater than or equal to the width of the first short circuit branch and the width of the second short circuit branch. The filter characteristics designed based on the topology of the present embodiment will be described in detail in the filter of another embodiment.
Another embodiment of the present utility model further provides a filter including any one of the above-described topologically designed filters. The filter also included a circuit board having a dielectric constant of 3.38, a dielectric loss of 0.0022, and a thickness of 0.813mm. The circuit board of the filter is 25.4mm by 12.0mm.
Further, referring to fig. 2, the lengths of the first and second parallel five lines are set to l P =9.7 mm, the length of the microstrip line is set to l 1 =10.2 mm, the lengths of the first and second short circuit branches are set to l 2 =10.35 mm; the transmission line width of the first parallel five line and the second parallel five line is set to w P Transmission line spacing of the first and second parallel five lines is set to s =0.1 mm P =0.06 mm, the width of the microstrip line being set to w 1 =2.2 mm, the widths of the first and second short circuit branches are set to w 2 ＝2.0mm。
It should be noted that, in the above embodiment, the design parameters of the topology structure affecting the filter performance include the width of the transmission line, the distance between adjacent transmission lines, the width of the microstrip line, and the widths of the first short circuit branch and the second short circuit branch, so in this embodiment, the influence of each parameter on the filter performance will be described in detail;
referring to fig. 3, the adjacent transmission line spacing s of the constituent parallel five lines is changed P The value of (2) does not change the ratio of the bandwidth of the dual passband filter to the center frequency of the two passbands, but by adjusting the spacing s between adjacent transmission lines that make up the parallel five lines P The reflection coefficient and insertion loss flatness within the passband can be optimized.
Referring to fig. 4, a distance s between the transmission lines connected to the five parallel lines p The influence on the performance of the dual-passband filter is similar, and the width w of the transmission line of the parallel five lines is changed P The value of (2) does not change the ratio of the bandwidth of the dual passband filter to the center frequency of the two passbands, but by adjusting the width w of the transmission lines making up the parallel five lines P The reflection coefficient and insertion loss flatness within the passband can be optimized.
Referring to fig. 5, the microstrip line width w is changed 1 The values of (a) do not change the position of the lower passband side of the first passband, but do change the positions of the upper passband side of the first passband, the lower passband side of the second passband, and the upper passband side of the second passband. In other words, the microstrip line width w is changed 1 Not only will the bandwidth of the two pass bands be changed, but also the ratio of the center frequencies of the two pass bands will be changed. With microstrip line width w 1 The value of (2) becomes larger, the bandwidths of the two pass bands become smaller, but the ratio of the center frequencies of the two pass bands becomes larger. Furthermore, by varying the microstrip line width w 1 The reflection coefficient and insertion loss flatness in the pass band can be optimized.
Referring to fig. 6, a short circuit branch width w is varied 2 The values of (2) do not change the positions of the lower passband side of the first passband, the upper passband side of the second passband, but change the position of the passband side of the second passband, in other words the width w of the short circuit branch 2 Only the bandwidth of the second passband and the ratio of the center frequencies of the two passbands will be changed without affecting the bandwidth of the first passband. Along with the width w of the short circuit branch 2 The value of (2) becomes larger, the bandwidth of the second passband becomes larger, but the ratio of the center frequencies of the two passbands becomes smaller. In addition, by varying the short circuit branch width w 2 The reflection coefficient in the passband and the flatness of the insertion loss in the passband can also be optimized.
From the above analysis, the ratio of passband bandwidth to center frequency of the wide dual-passband filter designed based on the topology of the present utility model is determined by the parameter w 1 And w 2 Control, adjustment of parameters s P And w P The passband internal reflection coefficient and insertion loss flatness can be optimized independently without affecting the passband bandwidth and center frequency ratio. But no matter how the parameter s is changed P 、w P 、w 1 、w 2 The filter designed based on this topology can only be a dual-passband filter.
Referring to fig. 7, in this embodiment, the lengths of the first parallel five line and the second parallel five line are set to be l, corresponding to the simulation result, for the design parameters based on the topology structure adopted by the filter in this embodiment P =9.7 mm, the length of the microstrip line is set to l 1 =10.2 mm, the lengths of the first and second short circuit branches are set to l 2 =10.35 mm; the transmission line width of the first parallel five line and the second parallel five line is set to w P Transmission line spacing of the first and second parallel five lines is set to s =0.1 mm P =0.06 mm, the width of the microstrip line being set to w 1 =2.2 mm, the widths of the first and second short circuit branches are set to w 2 ＝2.0mm。
As can be seen from fig. 7, in the first passband, the impedance bandwidth range with the reflection coefficient smaller than-10 dB is 1.546 to 3.728GHz, the passband center frequency is 2.637GHz, the passband absolute bandwidth is 2.182GHz, and the passband relative bandwidth is 82.7%; in the second passband, the impedance bandwidth range with the reflection coefficient smaller than-10 dB is 5.994 to 8.664GHz, the passband center frequency is 7.329GHz, the passband absolute bandwidth is 2.67GHz, and the passband relative bandwidth is 36.4%. In addition, there are two transmission poles within the first passband, respectively at 1.661,2.723,3.348ghz; three transmission poles are also arranged in the second passband and are respectively positioned at 6.578,7.102 and 8.518GHz, and the six transmission poles can ensure the flatness in the passband.
In the stopband between the two passband, the stopband bandwidth with the isolation degree larger than 15dB is in the range of 4.538 to 5.262GHz, the center frequency of the stopband is 4.9GHz, the absolute bandwidth of the stopband is 0.724GHz, and the relative bandwidth of the stopband is 14.8%. Six transmission zeros are also located in the stop band at 0,4.744,5.203, 10.378, 10.501, 10.785GHz, respectively. The six transmission zeroes ensure not only high selectivity of the wide double-passband filter, but also high isolation of the stop band.
As shown by comprehensive simulation results, for the dual-passband filter with the relative bandwidth of the first passband of 82.7% and the relative bandwidth of the second passband of 36.4%, the center frequency ratio of the two passbands is only 2.78, and the dual-passband filter has the characteristic of small center frequency ratio of the passbands.
The foregoing description is only of the optional embodiments of the present utility model, and is not intended to limit the scope of the utility model, and all the equivalent structural changes made by the description of the present utility model and the accompanying drawings or the direct/indirect application in other related technical fields are included in the scope of the utility model.
Claims (9)
1. The topological structure of the dual-passband filter with the small center frequency ratio is characterized by comprising a microstrip line, wherein one end of the microstrip line is symmetrically connected with one end of a first parallel five line and one end of a second parallel five line, and the other end of the microstrip line is symmetrically connected with one end of a first short circuit branch and one end of a second short circuit branch; the other end of the first parallel five wires is connected with the input end, the other end of the second parallel five wires is connected with the output end, and the other end of the first short circuit branch and the other end of the second short circuit branch are respectively grounded.
2. The topology of a dual passband filter of small center frequency ratio of claim 1, where the electrical length of the microstrip line, the electrical length of the first parallel five line, the electrical length of the second parallel five line, the electrical length of the first shorting stub, and the electrical length of the second shorting stub are all equal.
3. The topology of a dual-passband filter of small center frequency ratio of claim 2, wherein the electrical length of the microstrip line, the electrical length of the first parallel five lines, the electrical length of the second parallel five lines, the electrical length of the first shorting stub, and the electrical length of the second shorting stub are each set to a corresponding quarter wavelength at the center frequency of the two passband intermediate stop bands.
4. The topology of a dual passband filter of small center frequency ratio of claim 1, wherein said first and second parallel five lines each comprise five transmission lines arranged in parallel with each other.
5. The topology of a small center frequency ratio dual band filter of claim 4, wherein parameters of topology include a width of said transmission lines, a spacing between adjacent ones of said transmission lines, a width of said microstrip lines, and a width of said first and second shorting stubs.
6. A filter comprising a topologically designed filter as claimed in any one of claims 1 to 5.
7. The filter of claim 6, further comprising a circuit board having a dielectric constant of 3.38, a dielectric loss of 0.0022, and a thickness of 0.813mm.
8. The filter of claim 7, wherein the filter has a circuit board size of 25.4mm by 12.0mm.
9. The filter of claim 6, wherein the lengths of the first and second parallel five lines are set to 9.7mm, the length of the microstrip line is set to 10.2mm, and the lengths of the first and second shorting stubs are set to 10.35mm; the transmission line width of the first parallel five lines and the second parallel five lines is set to be 0.1mm, the transmission line distance of the first parallel five lines and the second parallel five lines is set to be 0.06mm, the width of the microstrip line is set to be 2.2mm, and the width of the first short circuit branch knot and the second short circuit branch knot is set to be 2.0mm.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202322303411.5U CN220797045U (en) | 2023-08-24 | 2023-08-24 | Topological structure of dual-passband filter with small center frequency ratio and filter |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202322303411.5U CN220797045U (en) | 2023-08-24 | 2023-08-24 | Topological structure of dual-passband filter with small center frequency ratio and filter |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN220797045U true CN220797045U (en) | 2024-04-16 |
Family
ID=90656932
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202322303411.5U Active CN220797045U (en) | 2023-08-24 | 2023-08-24 | Topological structure of dual-passband filter with small center frequency ratio and filter |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN220797045U (en) |
-
2023
- 2023-08-24 CN CN202322303411.5U patent/CN220797045U/en active Active
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN110034361B (en) | Miniaturized ultra-wideband filtering power division feed network for 5G communication and design method thereof | |
| CN108270061B (en) | Differential power divider with filtering characteristic | |
| CN111384534A (en) | Three-way band-pass power division filter | |
| CN117317551A (en) | Filter and communication equipment | |
| CN220797045U (en) | Topological structure of dual-passband filter with small center frequency ratio and filter | |
| CN116937092A (en) | Topological structure of dual-passband filter with small center frequency ratio and filter | |
| CN221239780U (en) | Topological structure of high-selectivity compact ultra-wideband filter and filter | |
| CN220628194U (en) | Topological structure of compact type wide passband filter and filter | |
| CN221102374U (en) | Wide double-passband filter based on parallel five lines | |
| CN220895819U (en) | Topological structure of broadband band-stop filter with narrow pass characteristic and filter | |
| CN221176617U (en) | Filter topological structure and three-mode-width double-passband filter | |
| CN220798234U (en) | Topological structure, filter and communication equipment | |
| CN220895818U (en) | Topological structure of small-sized high-selectivity broadband band-stop filter and filter | |
| CN220672826U (en) | Notch-controllable filter and communication equipment | |
| Gu et al. | Miniaturization and harmonic suppression open-loop resonator bandpass filter with capacitive terminations | |
| CN221176618U (en) | Topological structure and five-order miniaturized wide passband filter | |
| CN220963707U (en) | Topological structure, band elimination filter and communication equipment | |
| CN220474867U (en) | Topological structure of high-selectivity broadband band-stop filter and filter | |
| CN111682292A (en) | Four-way band-pass power division filter based on four-mode resonator | |
| CN117096560A (en) | Wide double-passband filter based on parallel five lines | |
| CN220692296U (en) | Filter and communication equipment | |
| CN110518315B (en) | Multi-frequency band elimination filter based on asymmetric tree-shaped branch knot loaded multimode resonator | |
| CN220672827U (en) | Dual-passband filter and communication equipment | |
| CN221226534U (en) | Filter and communication equipment | |
| CN117239376A (en) | Topological structure, dual-passband filter and communication equipment |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant | ||
| GR01 | Patent grant |