Topological structure, broadband band-pass filter and communication equipment
By designing a specific topology, including multiple microstrip lines and short-circuit stubs, the problem of poor selectivity in miniaturized broadband bandpass filters was solved, and a broadband bandpass filter with high selectivity and high isolation was realized.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-14
- Publication Date
- 2026-03-06
AI Technical Summary
Existing miniaturized broadband bandpass filters suffer from poor selectivity, which hinders their application in modern wireless communication systems.
A specific topology design is adopted, including the input end, output end, multiple microstrip lines and short-circuit stubs, forming seven transmission poles and seven transmission zeros to improve the selectivity and isolation of the filter.
While maintaining miniaturization, high selectivity and high isolation of the broadband bandpass filter are achieved, ensuring passband flatness.
Smart Images
Figure CN223978069U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of topology technology, and in particular to a topology, a broadband bandpass filter, and a communication device. Background Technology
[0002] With the rapid development of modern wireless communication technology, people's demand for broadband communication systems that can realize high-speed data transmission is increasing, and it has become a key research object for practitioners in related fields. Broadband bandpass filters with high selectivity and miniaturization characteristics have attracted the attention of many scholars and engineers, and have been studied in depth.
[0003] In the process of realizing this utility model, the inventors discovered that miniaturized broadband bandpass filters often suffer from poor selectivity, which severely restricts their use in modern wireless communication systems. Utility Model Content
[0004] This utility model provides a topology, a broadband bandpass filter, and a communication device, and the main technical problem it solves is the poor selectivity of current broadband bandpass filters.
[0005] To solve the above-mentioned technical problems, the present invention provides a technical solution as follows: A topology structure is provided, including an input terminal, an output terminal, a first parallel line, a first three-parallel line, a second three-parallel line, a first microstrip line, a second microstrip line, a third microstrip line, a fourth microstrip line, a fifth microstrip line, a sixth microstrip line, a seventh microstrip line, an eighth microstrip line, a first short-circuit stub, a second short-circuit stub, a third short-circuit stub, and a fourth short-circuit stub; wherein, one end of the first parallel line is connected to one end of the first microstrip line, one end of the first three-parallel line, and one end of the third microstrip line, respectively; the other end of the first microstrip line is connected to one end of the second microstrip line; the other end of the second microstrip line is connected to the first short-circuit stub; the other end of the first three-parallel line is connected to the input terminal; and the third microstrip line… The other end of the first parallel line is connected to one end of the fourth microstrip line, and the other end of the fourth microstrip line is connected to the second short-circuit stub. The other end of the first parallel line is connected to one end of the sixth microstrip line, one end of the second parallel three-line, and one end of the eighth microstrip line. The other end of the sixth microstrip line is connected to one end of the fifth microstrip line, and the other end of the fifth microstrip line is connected to the third short-circuit stub. The other end of the third short-circuit stub is connected to the other end of the first short-circuit stub and grounded. The other end of the second parallel three-line is connected to the output terminal. The other end of the eighth microstrip line is connected to one end of the seventh microstrip line, and the other end of the seventh microstrip line is connected to one end of the fourth short-circuit stub. The other end of the fourth short-circuit stub is connected to the second short-circuit stub and grounded.
[0006] Optionally, the first parallel line, the first three parallel lines, the second three parallel lines, the second microstrip line, the fourth microstrip line, the fifth microstrip line, and the seventh microstrip line are parallel to each other.
[0007] Optionally, the first parallel line, the first three parallel lines, the second three parallel lines, the second microstrip line, the fourth microstrip line, the fifth microstrip line, and the seventh microstrip line are all perpendicular to the first microstrip line, the third microstrip line, the sixth microstrip line, the eighth microstrip line, the first short-circuit stub, the second short-circuit stub, the third short-circuit stub, and the fourth short-circuit stub.
[0008] Optionally, the first parallel three lines include a first transmission line, a second transmission line, and a third transmission line that are parallel to each other and equidistant from each other along a first direction; the first parallel line includes a fourth transmission line and a fifth transmission line that are parallel to each other along a first direction; and the second parallel three lines include a sixth transmission line, a seventh transmission line, and an eighth transmission line that are parallel to each other and equidistant from each other along a first direction.
[0009] Optionally, the electrical lengths of the first parallel line, the first three parallel lines, and the second three parallel lines are equal; the electrical lengths of the first microstrip line, the third microstrip line, the sixth microstrip line, and the eighth microstrip line are equal; the electrical lengths of the second microstrip line and the seventh microstrip line are equal; the electrical lengths of the fourth microstrip line and the fifth microstrip line are equal; the electrical lengths of the first short-circuit stub and the fourth short-circuit stub are equal; and the electrical lengths of the second short-circuit stub and the third short-circuit stub are equal.
[0010] Optionally, the electrical lengths of the first parallel line, the first three parallel lines, and the second three parallel lines are all equal to a quarter wavelength corresponding to the center frequency of the broadband bandpass filter.
[0011] Optionally, the sum of the electrical length of the second microstrip line and the electrical length of the first short-circuit stub is equal to the sum of the electrical length of the fifth microstrip line and the electrical length of the third short-circuit stub; the sum of the electrical lengths of the first microstrip line, the second microstrip line, and the first short-circuit stub is greater than a quarter wavelength corresponding to the center frequency of the broadband bandpass filter.
[0012] Optionally, the characteristic impedances of the first microstrip line, the second microstrip line, the third microstrip line, the fourth microstrip line, the fifth microstrip line, the sixth microstrip line, the seventh microstrip line, the eighth microstrip line, the first short-circuit stub, the second short-circuit stub, the third short-circuit stub, and the fourth short-circuit stub are all equal.
[0013] To solve the above-mentioned technical problems, another technical solution adopted by this utility model is to provide a broadband bandpass filter, which is obtained through the above-mentioned topology design.
[0014] To solve the above-mentioned technical problems, another technical solution adopted by this utility model is to provide a communication device, including the above-mentioned broadband bandpass filter.
[0015] The beneficial effects of this utility model embodiment are as follows: Unlike the prior art, this utility model embodiment provides a topology, a broadband bandpass filter, and a communication device, including: an input terminal, an output terminal, a first parallel line, a first three-parallel line, a second three-parallel line, a first microstrip line, a second microstrip line, a third microstrip line, a fourth microstrip line, a fifth microstrip line, a sixth microstrip line, a seventh microstrip line, an eighth microstrip line, a first short-circuit stub, a second short-circuit stub, a third short-circuit stub, and a fourth short-circuit stub; wherein, one end of the first parallel line is connected to one end of the first microstrip line, one end of the first three-parallel line, and one end of the third microstrip line, respectively; the other end of the first microstrip line is connected to one end of the second microstrip line; the other end of the second microstrip line is connected to the first short-circuit stub; and the other end of the first three-parallel line is connected to the input... The first parallel line is connected to one end of the sixth microstrip line, one end of the second parallel three-line, and one end of the eighth microstrip line. The other end of the sixth microstrip line is connected to one end of the fifth microstrip line, and the other end of the fifth microstrip line is connected to the third short-circuit stub. The other end of the third short-circuit stub is connected to the other end of the first short-circuit stub and grounded. The other end of the second parallel three-line is connected to the output terminal. The other end of the eighth microstrip line is connected to one end of the seventh microstrip line, and the other end of the seventh microstrip line is connected to one end of the fourth short-circuit stub. The other end of the fourth short-circuit stub is connected to the second short-circuit stub and grounded. Based on the above topology, a broadband bandpass filter has seven transmission poles in its passband, ensuring passband flatness. It also has seven transmission zeros in its stopband, ensuring high selectivity and high isolation. This allows broadband bandpass filters to maintain a small size while still possessing high selectivity. Attached Figure Description
[0016] To more clearly illustrate the technical solutions of the embodiments of this application, the drawings used in the embodiments of this application will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on the drawings without creative effort.
[0017] Figure 1 This is a schematic diagram of the topology provided in an embodiment of the present utility model;
[0018] Figure 2 This is a schematic diagram of the layout of a broadband bandpass filter based on topology design provided in an embodiment of the present invention;
[0019] Figure 3 This is a schematic diagram of the layout of a broadband bandpass filter based on topology design provided in this embodiment of the present invention.
[0020] Figure 4 This is a simulation result diagram of the S-parameters of a broadband bandpass filter based on topology design provided in this embodiment of the present invention. Detailed Implementation
[0021] To facilitate understanding of this utility model, a more detailed description is provided below with reference to the accompanying drawings and specific embodiments. It should be noted that when an element is described as being "fixed to" another element, it can be directly on the other element, or one or more intermediate elements may exist between them. When an element is described as being "connected" to another element, it can be directly connected to the other element, or one or more intermediate elements may exist between them. The terms "vertical," "horizontal," "left," "right," and similar expressions used in this specification are for illustrative purposes only.
[0022] Unless otherwise defined, all technical and scientific terms used in this specification have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to limit the scope of the invention. The term "and / or" as used in this specification includes any and all combinations of one or more of the associated listed items.
[0023] Please see Figure 1The topology 100 includes: an input terminal 101, an output terminal 102, a first parallel line 103, a first three-parallel line 104, a second three-parallel line 105, a first microstrip line 106, a second microstrip line 107, a third microstrip line 108, a fourth microstrip line 109, a fifth microstrip line 110, a sixth microstrip line 111, a seventh microstrip line 112, an eighth microstrip line 113, a first short-circuit stub 114, a second short-circuit stub 115, a third short-circuit stub 116, and a fourth short-circuit stub 117. One end of the first parallel line 103 is connected to one end of the first microstrip line 106, one end of the first three-parallel line 104, and one end of the third microstrip line 108, respectively. The other end of the first microstrip line 106 is connected to one end of the second microstrip line 107. The other end of the second microstrip line 107 is connected to the first short-circuit stub 114. The other end of the first three-parallel line 104 is connected to the input terminal 101. The other end of the third microstrip line 108 is connected to one end of the fourth microstrip line 109. The other end of the fourth microstrip line 109 is connected to the second short-circuit stub 115. The other end of the first parallel line 103 is connected to one end of the sixth microstrip line 111, one end of the second parallel three-line 105, and one end of the eighth microstrip line 113, respectively. The other end of the sixth microstrip line 111 is connected to one end of the fifth microstrip line 110. The other end of the fifth microstrip line 110 is connected to the third short-circuit stub 116. The other end of the third short-circuit stub 116 is connected to the other end of the first short-circuit stub 114 and grounded. The other end of the second parallel three-line 105 is connected to the output terminal 102. The other end of the eighth microstrip line 113 is connected to one end of the seventh microstrip line 112. The other end of the seventh microstrip line 112 is connected to one end of the fourth short-circuit stub 117. The other end of the fourth short-circuit stub 117 is connected to the second short-circuit stub 115 and grounded.
[0024] In some embodiments, the first parallel line 103, the first parallel tri-line 104, the second parallel tri-line 105, the second microstrip line 107, the fourth microstrip line 109, the fifth microstrip line 110, and the seventh microstrip line 112 are parallel to each other.
[0025] Furthermore, the first parallel line 103, the first parallel triple line 104, the second parallel triple line 105, the second microstrip line 107, the fourth microstrip line 109, the fifth microstrip line 110, and the seventh microstrip line 112 are all perpendicular to the first microstrip line 106, the third microstrip line 108, the sixth microstrip line 111, the eighth microstrip line 113, the first short-circuit stub 114, the second short-circuit stub 115, the third short-circuit stub 116, and the fourth short-circuit stub 117.
[0026] In some embodiments, the first parallel tri-line 104 includes a first transmission line 1041, a second transmission line 1042, and a third transmission line 1043 that are parallel to and equidistantly spaced along the first direction X; the first parallel line 103 includes a fourth transmission line 1031 and a fifth transmission line 1032 that are parallel to and equidistant along the first direction X; and the second parallel tri-line 105 includes a sixth transmission line 1051, a seventh transmission line 1052, and an eighth transmission line 1053 that are parallel to and equidistant along the first direction X.
[0027] Please refer to the following for details. Figure 2 One end of the first transmission line 1041 and one end of the third transmission line 1043 are both connected to the input terminal 101. One end of the second transmission line 1042 is connected to one end of the first microstrip line 106, one end of the third microstrip line 108, and one end of the fourth transmission line 1031. The other end of the first microstrip line 106 is connected to the second microstrip line 107 and the first short-circuit stub 114 in sequence. The other end of the third microstrip line 108 is connected to the fourth microstrip line 109 and the second short-circuit stub 115 in sequence. One end of the fifth transmission line 1032 is connected to one end of the sixth microstrip line 111 and the eighth microstrip line 1042. One end of the microstrip line 113 is connected to one end of the seventh transmission line 1052; one end of the eighth transmission line 1053 and one end of the sixth transmission line 1051 are both connected to the output terminal 102; the other end of the sixth microstrip line 111 is connected to the fifth microstrip line 110 and the third microstrip line 108 in sequence, and the third short-circuit stub 116 and the first short-circuit stub 114 are connected and grounded together; the other end of the eighth microstrip line 113 is connected to the seventh microstrip line 112 and the fourth short-circuit stub 117 in sequence, and the fourth short-circuit stub 117 and the second short-circuit stub 115 are connected and grounded together.
[0028] In some embodiments, the electrical lengths of the first parallel line 103, the first parallel tri-line 104, and the second parallel tri-line 105 are equal; the electrical lengths of the first microstrip line 106, the third microstrip line 108, the sixth microstrip line 111, and the eighth microstrip line 113 are equal; the electrical lengths of the second microstrip line 107 and the seventh microstrip line 112 are equal; the electrical lengths of the fourth microstrip line 109 and the fifth microstrip line 110 are equal; the electrical lengths of the first short-circuit stub 114 and the fourth short-circuit stub 117 are equal; and the electrical lengths of the second short-circuit stub 115 and the third short-circuit stub 116 are equal.
[0029] Furthermore, the electrical lengths of the first parallel line 103, the first parallel triple line 104, and the second parallel triple line 105 are all equal to a quarter wavelength corresponding to the center frequency of the broadband bandpass filter. The sum of the electrical lengths of the second microstrip line 107 and the first short-circuit stub 114 is equal to the sum of the electrical lengths of the fifth microstrip line 110 and the third short-circuit stub 116; the sum of the electrical lengths of the first microstrip line 106, the second microstrip line 107, and the first short-circuit stub 114 is greater than a quarter wavelength corresponding to the center frequency of the broadband bandpass filter.
[0030] In some embodiments, the characteristic impedances of the first microstrip line 106, the second microstrip line 107, the third microstrip line 108, the fourth microstrip line 109, the fifth microstrip line 110, the sixth microstrip line 111, the seventh microstrip line 112, the eighth microstrip line 113, the first short-circuit stub 114, the second short-circuit stub 115, the third short-circuit stub 116, and the fourth short-circuit stub 117 are all equal.
[0031] To facilitate understanding, this utility model also provides a simulation experiment embodiment of a broadband bandpass filter obtained based on the above-described topology 100. The broadband bandpass filter is mounted on a circuit board with a dielectric constant of 3.38, a dielectric loss of 0.0022, and a thickness of 0.813 mm.
[0032] The layout of a broadband bandpass filter, such as... Figure 2 and Figure 3 As shown. The specified layout size is 34mm * 13.1mm, and the specific dimensions of the broadband bandpass filter are: l T =9.8mm,s T =0.1mm,w T =0.2mm,l p =9.8mm,s p =0.1mm,w p =0.2mm, l1=5.8mm, l2=3.65mm, l3=3.95mm, l4=0.9mm, l5=1.2mm, w1=0.5mm.
[0033] in:
[0034] l T This indicates the physical length of the first parallel tri-line 104 or the physical length of the second parallel tri-line 105;
[0035] s TThis represents the spacing between any two adjacent pairs of the first transmission line 1041, the second transmission line 1042, and the third transmission line 1043, or the spacing between any two adjacent pairs of the sixth transmission line 1051, the seventh transmission line 1052, and the eighth transmission line 1053.
[0036] w T This indicates the physical width of the first transmission line 1041, the second transmission line 1042, or the third transmission line 1043, or the physical width of the sixth transmission line 1051, the seventh transmission line 1052, or the eighth transmission line 1053.
[0037] l p This indicates the physical length of the first parallel line 103;
[0038] s p This indicates the spacing between the fourth transmission line 1031 and the fifth transmission line 1032;
[0039] w p This indicates the physical width of the fourth transmission line 1031 and the fifth transmission line 1032;
[0040] l1 represents the physical length of the first microstrip line 106 or the third microstrip line 108, the physical length of the sixth microstrip line 111 or the physical length of the eighth microstrip line 113.
[0041] l2 represents the physical length of the second microstrip line 107 or the physical length of the seventh microstrip line 112;
[0042] l3 represents the physical length of the fourth microstrip line 109 or the physical length of the fifth microstrip line 110;
[0043] l4 represents the physical length of the second short-circuit stub 115 or the physical length of the third short-circuit stub 116;
[0044] l5 represents the physical length of the first short-circuit stub 114 or the physical length of the fourth short-circuit stub 117;
[0045] w1 represents the physical width of the first microstrip line 106, the second microstrip line 107, the third microstrip line 108, the fourth microstrip line 109, the fifth microstrip line 110, the sixth microstrip line 111, the seventh microstrip line 112, the eighth microstrip line 113, the first short-circuit stub 114, the second short-circuit stub 115, the third short-circuit stub 116, or the fourth short-circuit stub 117.
[0046] Combination Figure 4The S-parameter simulation results are shown in the figure. The broadband bandpass filter has a reflection coefficient better than -10dB in the passband range from 2.17GHz to 7.45GHz, a center frequency of 4.81GHz, an absolute bandwidth of 5.28GHz, and a relative bandwidth of 109.8%. Furthermore, there are seven transmission poles in the passband, located at 2.24GHz, 2.51GHz, 3.44GHz, 4.14GHz, 5.55GHz, 6.4GHz, and 7.29GHz, which ensure the flatness of the passband. There are seven transmission zeros in the stopband, located at 0GHz, 0.2GHz, 0.96GHz, 7.84GHz, 8.58GHz, 9.05GHz, and 10.69GHz, which ensure the filter's high selectivity and high isolation.
[0047] Through the simulation examples of the above topology 100, it can be demonstrated that the broadband bandpass filter designed based on the above topology 100 has high selectivity while maintaining its miniaturization characteristics.
[0048] This utility model also provides an embodiment of a communication device, which includes the above-mentioned broadband bandpass filter. For the specific structure and function of the above-mentioned broadband bandpass filter, please refer to the above embodiments, which will not be repeated here.
[0049] It should be noted that while the preferred embodiments of this utility model are provided in the specification and accompanying drawings, this utility model can be implemented in many different forms and is not limited to the embodiments described herein. These embodiments are not intended to impose additional limitations on the content of this utility model; their purpose is to provide a more thorough and comprehensive understanding of the disclosure of this utility model. Furthermore, the above-described technical features can be combined with each other to form various embodiments not listed above, all of which are considered to be within the scope of this utility model specification. Moreover, those skilled in the art can make improvements or modifications based on the above description, and all such improvements and modifications should fall within the protection scope of the appended claims.
Claims
1. A topology, characterized in that, The topology structure comprises: an input terminal, an output terminal, a first parallel line, a first parallel three-line, a second parallel three-line, a first microstrip line, a second microstrip line, a third microstrip line, a fourth microstrip line, a fifth microstrip line, a sixth microstrip line, a seventh microstrip line, an eighth microstrip line, a first short-circuit stub, a second short-circuit stub, a third short-circuit stub and a fourth short-circuit stub; wherein one end of the first parallel line is connected to one end of the first microstrip line, one end of the first parallel three-line and one end of the third microstrip line respectively, the other end of the first microstrip line is connected to one end of the second microstrip line, the other end of the second microstrip line is connected to the first short-circuit stub, the other end of the first parallel three-line is connected to the input terminal, the other end of the third microstrip line is connected to one end of the fourth microstrip line, the other end of the fourth microstrip line is connected to the second short-circuit stub, the other end of the first parallel line is connected to one end of the sixth microstrip line, one end of the second parallel three-line and one end of the eighth microstrip line respectively, the other end of the sixth microstrip line is connected to one end of the fifth microstrip line, the other end of the fifth microstrip line is connected to the third short-circuit stub, the other end of the third short-circuit stub is connected to the other end of the first short-circuit stub and grounded, the other end of the second parallel three-line is connected to the output terminal, the other end of the eighth microstrip line is connected to one end of the seventh microstrip line, the other end of the seventh microstrip line is connected to one end of the fourth short-circuit stub, the other end of the fourth short-circuit stub is connected to the second short-circuit stub and grounded.
2. The topology structure according to claim 1, wherein: the first parallel line, the first parallel three-line, the second parallel three-line, the second microstrip line, the fourth microstrip line, the fifth microstrip line and the seventh microstrip line are parallel to each other.
3. The topology structure according to claim 2, wherein: the first parallel line, the first parallel three-line, the second parallel three-line, the second microstrip line, the fourth microstrip line, the fifth microstrip line and the seventh microstrip line are perpendicular to the first microstrip line, the third microstrip line, the sixth microstrip line, the eighth microstrip line, the first short-circuit stub, the second short-circuit stub, the third short-circuit stub and the fourth short-circuit stub.
4. The topology structure according to claim 1, wherein: the first parallel three-line comprises a first transmission line, a second transmission line and a third transmission line which are parallel and equally spaced in a first direction; the first parallel line comprises a fourth transmission line and a fifth transmission line which are parallel in the first direction; the second parallel three-line comprises a sixth transmission line, a seventh transmission line and an eighth transmission line which are parallel and equally spaced in the first direction.
5. The topology structure according to claim 1, wherein: an electrical length of the first parallel line, an electrical length of the first parallel three-line and an electrical length of the second parallel three-line are equal; an electrical length of the first microstrip line, an electrical length of the third microstrip line, an electrical length of the sixth microstrip line and an electrical length of the eighth microstrip line are equal; an electrical length of the second microstrip line is equal to an electrical length of the seventh microstrip line; an electrical length of the fourth microstrip line is equal to an electrical length of the fifth microstrip line; an electrical length of the first short-circuit stub is equal to an electrical length of the fourth short-circuit stub; an electrical length of the second short-circuit stub is equal to an electrical length of the third short-circuit stub.
6. The topology of claim 5, wherein, an electrical length of the first parallel line, an electrical length of the first parallel three-line, and an electrical length of the second parallel three-line are all equal to a corresponding quarter wavelength at a center frequency of the wideband bandpass filter.
7. The topology of claim 5, wherein, a sum of an electrical length of the second microstrip line and an electrical length of the first short-circuit stub is equal to a sum of an electrical length of the fifth microstrip line and an electrical length of the third short-circuit stub; a sum of an electrical length of the first microstrip line, an electrical length of the second microstrip line, and an electrical length of the first short-circuit stub is greater than a corresponding quarter wavelength at a center frequency of the wideband bandpass filter.
8. The topology of any one of claims 1-7, wherein, a characteristic impedance of the first microstrip line, a characteristic impedance of the second microstrip line, a characteristic impedance of the third microstrip line, a characteristic impedance of the fourth microstrip line, a characteristic impedance of the fifth microstrip line, a characteristic impedance of the sixth microstrip line, a characteristic impedance of the seventh microstrip line, a characteristic impedance of the eighth microstrip line, a characteristic impedance of the first short-circuit stub, a characteristic impedance of the second short-circuit stub, a characteristic impedance of the third short-circuit stub, and a characteristic impedance of the fourth short-circuit stub are all equal.
9. A wideband bandpass filter, characterized by, is designed by the topology of any one of claims 1-8.
10. A communication device comprising the wideband bandpass filter of claim 9.