CN106921012B - Highly selective double frequency band-pass filter - Google Patents
Highly selective double frequency band-pass filter Download PDFInfo
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- CN106921012B CN106921012B CN201710162778.6A CN201710162778A CN106921012B CN 106921012 B CN106921012 B CN 106921012B CN 201710162778 A CN201710162778 A CN 201710162778A CN 106921012 B CN106921012 B CN 106921012B
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- microstrip line
- short circuit
- highly selective
- frequency band
- pass filter
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01P—WAVEGUIDES; RESONATORS, LINES, OR OTHER DEVICES OF THE WAVEGUIDE TYPE
- H01P1/00—Auxiliary devices
- H01P1/20—Frequency-selective devices, e.g. filters
- H01P1/201—Filters for transverse electromagnetic waves
- H01P1/203—Strip line filters
- H01P1/20327—Electromagnetic interstage coupling
- H01P1/20354—Non-comb or non-interdigital filters
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Abstract
The present invention provides a kind of highly selective double frequency band-pass filter, two first microstrip lines, input, output end and the second microstrip line including dielectric-slab upper surface is arranged in.The both ends of each first microstrip line are respectively arranged with open-circuited load and short circuit load, and the middle part of two first microstrip lines is connected by the second microstrip line；Wherein on first microstrip line, output end is connected on another first microstrip line for input terminal connection；The both ends of second microstrip line are connected to input, output end respectively and are located in same horizontal line, which is mutually perpendicular to as the first central axis, the second central axis with the first central axis；Short circuit metallic column is arranged in the end of short circuit load, and short circuit metallic column is connect with the ground metal layer that dielectric-slab lower surface is arranged in.Highly selective double frequency band-pass filter of the invention has good inhibitory effect to out of band signal, have it is highly selective, introduce noise it is few, avoid interfering radio-frequency front-end.
Description
Technical field
The present invention relates to frequency microwave field of communication technology more particularly to a kind of highly selective double frequency band-pass filters.
Background technique
A kind of critically important device of the filter as radio-frequency front-end, can filter out out-of-band noise, improve the spirit of circuit system
Sensitivity.Microstrip filter is a kind of device for separating different frequency microwave signal.Its main function is to inhibit not needing
Signal, prevent it from only allowing the signal of needs to pass through by filter.In microwave circuit system, the performance pair of filter
The performance indicator of circuit system has a great impact.Due to the diversity of communications band in Modern Communication System, the prior art
The selectivity of bandpass filter is often inadequate, is not able to satisfy the multifarious demand of communications band, affects entire communication system
Performance.
Summary of the invention
The purpose of the present invention is to provide a kind of highly selective double frequency band-pass filters, it is intended to solve existing bandpass filter
The not high technical problem of selectivity.
To achieve the above object, the present invention provides a kind of highly selective double frequency band-pass filters, including dielectric-slab, etching
In two first microstrip lines, input, output end and the second microstrip line of dielectric-slab upper surface and setting in dielectric-slab following table
The ground metal layer in face, the highly selective double frequency band-pass filter are symmetrical above and below about the first central axis and about in second
Mandrel line bilateral symmetry, in which:
The both ends of each first microstrip line are respectively arranged with an open-circuited load and a short circuit load, four open circuits
Load and four short circuit loads are connected on the second microstrip line by two first microstrip lines, and the middle part of two first microstrip lines is logical
Cross the connection of the second microstrip line；
There is spacing distance between two first microstrip lines, which is equal to the length of the second microstrip line；
It is micro- that one end of one open-circuited load and one end of a short circuit load are connected to first in mutually perpendicular manner
Both ends with line, the spacing distance between less than two first microstrip lines of the distance between two adjacent short circuit loads；
One end of the input terminal is disposed therein the middle part of first microstrip line and the other end of the input terminal extends
To a long edge of dielectric-slab；
One end of the output end is disposed therein the middle part of another first microstrip line and the other end of the output end prolongs
Extend to another long edge of dielectric-slab；
The both ends of second microstrip line are connected to input, output end respectively and are located in same horizontal line, the level
Line is mutually perpendicular to as the first central axis, the second central axis with the first central axis；
The end of the short circuit load is provided with short circuit metallic column, and the short circuit metallic column is penetrated from the upper surface of dielectric-slab
To the lower surface of dielectric-slab, and it is connect with the ground metal layer that dielectric-slab lower surface is arranged in.
Preferably, the ground metal layer is the deposited copper metal layer being laid on dielectric-slab lower surface.
Preferably, two first microstrip lines are arranged in parallel on the upper surface of dielectric-slab and about the second center
Axis bilateral symmetry, the both ends of second microstrip line are vertically connected between two first microstrip lines.
Preferably, one end of the open-circuited load and the quantity of short circuit load are four, each first microstrip line
An open-circuited load and a short circuit load is respectively set in both ends.
Preferably, first microstrip line, the second microstrip line, open-circuited load, short circuit load, input, output end are
The metal copper sheet of strip structure.
Preferably, the length of first microstrip line is 2L1+W=2 × 22.5mm+1.66mm=46.66mm, width is
W1=1.22mm, the length of second microstrip line is L0=9.78mm, width W0=1.35mm, the input terminal and output
It is W=1.66mm that the length at end, which is L=14.4mm, width,.
Preferably, the length of the short circuit load be L2=11mm, width W2=3mm, the length of the open-circuited load
For L3=11mm, width W3=1.7mm.
Preferably, the shape of the short circuit metallic column is column.
Compared to the prior art, highly selective double frequency band-pass filter of the present invention is loaded with four on two microstrip lines
A open-circuited load and four short circuit loads, the length and width by adjusting open-circuited load and short circuit load can be in special frequency band
Transmission zero is formed, so that the microstrip line of script has filtering performance, so that band logical with higher is selective, it can be outer to band
Signal has good inhibitory effect, to passband signal have it is highly selective, introduce less noise, avoid that radio-frequency front-end is caused to do
It disturbs.Relative to existing bandpass filter, four open-circuited loads and four short circuit loads are connected to biography by two first microstrip lines
It unites on microstrip line, and the length and width by changing microstrip line, highly selective double frequency band-pass filter of the present invention can be made
Wave device reaches good matching effect in working frequency range.
Detailed description of the invention
Fig. 1 is the surface structure schematic diagram of the highly selective double frequency band-pass filter of the present invention.
Fig. 2 is the lower surface configuration schematic diagram of the highly selective double frequency band-pass filter of the present invention.
Fig. 3 is that the highly selective double frequency band-pass filter of the present invention is illustrated by the S parameter result that electromagnetic simulation software emulates
Figure.
Specific embodiment
The present invention is described in further detail combined with specific embodiments below, and following embodiment is to solution of the invention
It releases, the invention is not limited to following embodiments.
Refering to what is shown in Fig. 1, Fig. 1 is the surface structure schematic diagram of the highly selective double frequency band-pass filter of the present invention.At this
In embodiment, the highly selective double frequency band-pass filter includes dielectric-slab 1, etching at two first of 1 upper surface of dielectric-slab
Microstrip line 10, input terminal P1, output end P2 and the second microstrip line 11 and the ground metal layer 14 that dielectric-slab lower surface is set
(referring to Fig. 2).The both ends of each first microstrip line 10 are respectively arranged with open-circuited load 12 and short circuit load 13, and two first
The middle part of microstrip line 10 is connected by the second microstrip line 11, and one end of input terminal P1 is disposed therein first microstrip line 10
The other end of middle part and input terminal P1 extend to a long edge of dielectric-slab 1, and one end of output end P2 is disposed therein another
The middle part of the first microstrip line of root 10 and the other end of output end P2 extend to another long edge of pcb board 2.Each short circuit is negative
The end for carrying 13 is provided with short circuit metallic column 130, and the shape of the short circuit metallic column 130 can be column, for example, it is cylindrical or
Strip cylindricality.The specific plate type of the dielectric-slab 1 is Roger RO4350B, and wherein relative dielectric constant 3.66, plate thickness are
0.762mm。
The both ends of second microstrip line 11 are connected to input terminal P1, output end P2 respectively and are located at same horizontal line ab
On, the present embodiment is using horizontal line ab as the first central axis ab.Highly selective double frequency band-pass filter of the present invention about
First central axis ab is symmetrical above and below, and about the second central axis cd bilateral symmetry, the first central axis ab and the second center
Axis cd is mutually perpendicular to.Two first microstrip lines 10 upper surface arranged in parallel in dielectric-slab 1 and about the second central axis
Line cd is symmetrical, and the second microstrip line 11 is mutually connected vertically with two first microstrip lines 10.One end of the open-circuited load 12 and short
One end of road load 13 is arranged in the both ends of each first microstrip line 10 with any angle of intersection and is interconnected.In this implementation
In example, one end of one end of the open-circuited load 12 and short circuit load 13 is first micro- at each with mutually orthogonal angle setting
Both ends with line 10 and be interconnected.
It should be noted that the long edge that this implementation defines dielectric-slab 1 refers to the medium parallel with the second central axis cd
Two edges of plate 1.It is separated with interval between two first microstrip lines 10, which is equal to the length of the second microstrip line 11.
When one end of open-circuited load 12 and one end of short circuit load 13 are connected to the both ends of the first microstrip line 10 in mutually perpendicular manner,
Spacing distance between less than two first microstrip lines 10 of the distance between two adjacent short circuit loads 13.Due to two it is first micro-
Both ends with line 10 are provided with an open-circuited load 12 and a short circuit load 13, therefore highly selective double frequency of the present invention
There are four open-circuited load 12 and four short circuit loads 13 for bandpass filter tool.Four open-circuited loads 12 and four short circuit loads 13 make
Highly selective double frequency band-pass filter of the present invention is gathered around in any working frequency range there are two stopband so that of the invention
The highly selective double frequency band-pass filter has dual frequency characteristics, band logical selectivity with higher.
In the present embodiment, the first microstrip line 10, the second microstrip line 11, open-circuited load 12, short circuit load 13, input terminal
P1, output end P2 are the metal copper sheet of strip structure.Highly selective double frequency band-pass filter of the present invention is relative to existing
Bandpass filter, four open-circuited loads 12 and four short circuit loads 13 are connected to the second microstrip line by two first microstrip lines 12
On 11, designer is designed by changing the length and width of microstrip line, can make highly selective double frequency band-pass filter of the present invention
Wave device reaches good matching effect in working frequency range.
The present invention realizes double frequency with working band in 2.61GHz to 3.23GHz and in 4.75GHz to 5.02GHz
For characteristic, by be arranged in for specific embodiment the first microstrip line 10 of 1 upper surface of dielectric-slab, the second microstrip line 11,
The length and width of open-circuited load 12, short circuit load 13, input terminal P1, output end P2.In the present embodiment, the first microstrip line 10
Length be 2L1+W=2 × 22.5mm+1.66mm=46.66mm, the width of the first microstrip line 10 is W1=1.22mm.Second
The length of microstrip line 11 is L0=9.78mm, and the width of the second microstrip line 11 is W0=1.35mm.The input terminal P1 and output
The length of end P2 is that the width of L=14.4mm, input terminal P1 and output end P2 are W=1.66mm.The open-circuited load 12
Length be L3=11mm, the width of open-circuited load 12 is W3=1.7mm；The length of short circuit load 13 is L2=11mm, short circuit
The width of load 13 is W2=3mm.It should be noted that the metal copper thickness being arranged on pcb board is generally um grades, therefore
The present invention is not to the first microstrip line 10, the second microstrip line 11, open-circuited load 12, short circuit load 13, input terminal P1, output end P2
Metal copper thickness limit, have no effect on the characteristic of highly selective double frequency band-pass filter of the present invention.
Refering to what is shown in Fig. 2, Fig. 2 is the lower surface configuration schematic diagram of the highly selective double frequency band-pass filter of the present invention.At this
In embodiment, the short circuit metallic column 130 of each 13 end of short circuit load is penetrated from the upper surface of dielectric-slab 1 to dielectric-slab 1
Lower surface is connected to the ground metal layer 14 of 1 lower surface of dielectric-slab, which is 1 lower surface of dielectric-slab that is laid in
Deposited copper metal layer.
Highly selective double frequency band-pass filter of the present invention is by said structure design, by conventional microstrip line
Four open-circuited loads 12 and four short circuit loads 13 are loaded with, by the length and width that adjust open-circuited load 12 and short circuit load 13
Degree can form transmission zero in particular job frequency band, so that the microstrip line of script has filtering performance, it can be to out of band signal
Have good inhibitory effect, to passband signal have it is highly selective, introduce less noise, avoid interfering radio-frequency front-end.
Refering to what is shown in Fig. 3, Fig. 3 is the S that the highly selective double frequency band-pass filter of the present invention is emulated by electromagnetic simulation software
Parametric results schematic diagram.Generally, generally, bandpass filter allows different frequency bands signal to enter system, filters out out of band signal
Or noise.From figure 3, it can be seen that in 2.61GHz to 3.23GHz and in 4.75GHz to 5.02GHz, it is of the present invention
Highly selective double frequency band-pass filter reflection coefficient (| S11 |) in -10dB hereinafter, illustrating highly selective double frequency band-pass filter
Wave device can work in 2.61GHz to 3.23GHz and in 4.75GHz to 5.02GHz, therefore can realize dual frequency characteristics.
At 2.13GHz, the transmission characteristic of highly selective double frequency band-pass filter of the present invention (| S21 |) it can reach -35.8dB,
At 4.13GHz, | S21 | it can reach -50.6dB, at 5.27GHz, | S21 | it can reach -34dB, so Gao Xuan of the present invention
Selecting property double frequency band-pass filter has highly selective.It follows that highly selective double frequency band-pass filter of the invention can be right
Out of band signal has good inhibitory effect, to passband signal have it is highly selective, introduce less noise, avoid making radio-frequency front-end
At interference, therefore the performance of microwave circuit can be greatly improved.
Highly selective double frequency band-pass filter of the present invention is loaded with four 12 Hes of open-circuited load on two microstrip lines
Four short circuit loads 13, the length and width by adjusting open-circuited load 12 and short circuit load 13 can form biography in special frequency band
Defeated zero point, so that the microstrip line of script has filtering performance, so that band logical with higher is selective.High selection of the present invention
Property double frequency band-pass filter relative to existing bandpass filter, four open-circuited loads 12 and four short circuit loads 13 are passed through two
First microstrip line 12 is connected on conventional microstrip line, and the length and width by changing microstrip line, can make institute of the present invention
It states highly selective double frequency band-pass filter and reaches good matching effect in working frequency range.
The above is only a preferred embodiment of the present invention, is not intended to limit the scope of the invention, all to utilize this hair
Equivalent structure or equivalent flow shift made by bright specification and accompanying drawing content is applied directly or indirectly in other relevant skills
Art field, is included within the scope of the present invention.
Claims (7)
1. a kind of highly selective double frequency band-pass filter, including dielectric-slab, etching dielectric-slab upper surface two first micro-strips
Line, input, output end and the second microstrip line and the ground metal layer that dielectric-slab lower surface is set, which is characterized in that institute
State highly selective double frequency band-pass filter it is symmetrical above and below about the first central axis and about the second central axis bilateral symmetry,
In:
The both ends of each first microstrip line are respectively arranged with an open-circuited load and a short circuit load, four open-circuited loads
It is connected on the second microstrip line with four short circuit loads by two first microstrip lines, the middle parts of two first microstrip lines passes through the
The connection of two microstrip lines；
There is spacing distance between two first microstrip lines, which is equal to the length of the second microstrip line；
One end of one open-circuited load and one end of a short circuit load are connected to the first microstrip line in mutually perpendicular manner
Both ends, the spacing distance between less than two first microstrip lines of the distance between two adjacent short circuit loads；
One end of the input terminal is disposed therein the middle part of first microstrip line and the other end of the input terminal extends to Jie
One long edge of scutum；
One end of the output end is disposed therein the middle part of another first microstrip line and the other end of the output end extends to
Another long edge of dielectric-slab；
The both ends of second microstrip line are connected to input, output end respectively and are located in same horizontal line, which makees
For the first central axis, the second central axis is mutually perpendicular to the first central axis；
The end of the short circuit load is provided with short circuit metallic column, and the short circuit metallic column is penetrated from the upper surface of dielectric-slab to Jie
The lower surface of scutum, and connect with the ground metal layer that dielectric-slab lower surface is arranged in.
2. highly selective double frequency band-pass filter according to claim 1, which is characterized in that the ground metal layer is deposited
The deposited copper metal layer being located on dielectric-slab lower surface.
3. highly selective double frequency band-pass filter according to claim 1, which is characterized in that two first microstrip lines
It is arranged in parallel on the upper surface of dielectric-slab and about the second central axis bilateral symmetry, the both ends of second microstrip line
It is vertically connected between two first microstrip lines.
4. highly selective double frequency band-pass filter according to claim 1, which is characterized in that first microstrip line,
Two microstrip lines, open-circuited load, short circuit load, input, output end are the metal copper sheet of strip structure.
5. highly selective double frequency band-pass filter according to claim 4, which is characterized in that the length of first microstrip line
Degree is 2L1+W=2 × 22.5mm+1.66mm=46.66mm, width W1=1.22mm, and the length of second microstrip line is
It is W=that the length of L0=9.78mm, width W0=1.35mm, the input terminal and output end, which is L=14.4mm, width,
1.66mm。
6. highly selective double frequency band-pass filter according to claim 5, which is characterized in that the length of the short circuit load
For L2=11mm, width W2=3mm, the length of the open-circuited load is L3=11mm, width W3=1.7mm.
7. highly selective double frequency band-pass filter according to claim 1, which is characterized in that the shape of the short circuit metallic column
Shape is column.
Priority Applications (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710162778.6A CN106921012B (en) | 2017-03-18 | 2017-03-18 | Highly selective double frequency band-pass filter |
| PCT/CN2017/107192 WO2018171179A1 (en) | 2017-03-18 | 2017-10-21 | Dual-band bandpass filter with high selectivity |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710162778.6A CN106921012B (en) | 2017-03-18 | 2017-03-18 | Highly selective double frequency band-pass filter |
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| Publication Number | Publication Date |
|---|---|
| CN106921012A CN106921012A (en) | 2017-07-04 |
| CN106921012B true CN106921012B (en) | 2019-03-26 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN201710162778.6A Expired - Fee Related CN106921012B (en) | 2017-03-18 | 2017-03-18 | Highly selective double frequency band-pass filter |
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| Country | Link |
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| CN (1) | CN106921012B (en) |
| WO (1) | WO2018171179A1 (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106921012B (en) * | 2017-03-18 | 2019-03-26 | 深圳市景程信息科技有限公司 | Highly selective double frequency band-pass filter |
| CN206673067U (en) * | 2017-03-18 | 2017-11-24 | 深圳市景程信息科技有限公司 | Double frequency band-pass filter based on open-circuited load and short circuit load |
| JPWO2019215970A1 (en) * | 2018-05-08 | 2021-06-24 | ソニーグループ株式会社 | Filter circuit and communication device |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105449323A (en) * | 2016-01-11 | 2016-03-30 | 北京邮电大学 | Planar double-frequency filter with independently adjustable frequency band |
| CN206673067U (en) * | 2017-03-18 | 2017-11-24 | 深圳市景程信息科技有限公司 | Double frequency band-pass filter based on open-circuited load and short circuit load |
Family Cites Families (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP4171015B2 (en) * | 2005-09-29 | 2008-10-22 | 株式会社東芝 | Filter and wireless communication apparatus using the same |
| FR2897987B1 (en) * | 2006-02-28 | 2008-05-02 | Thales Sa | MICROWAVE FREQUENCY BAND FILTER |
| CN103985928B (en) * | 2014-05-09 | 2016-09-28 | 南京航空航天大学 | A kind of ultra broadband balanced filter based on slotted line structure |
| CN104319440A (en) * | 2014-10-29 | 2015-01-28 | 上海大学 | Hairpin type dual passband electrically-tunable microwave filter |
| CN104409808B (en) * | 2014-11-26 | 2017-03-29 | 西安电子科技大学 | Comb filter based on multimode resonator |
| CN105206905A (en) * | 2015-08-25 | 2015-12-30 | 南京理工大学 | Wide-stop-band three-mode dual-passband filter based on cross type multimode resonators |
| CN105514545B (en) * | 2016-01-19 | 2018-04-17 | 南京航空航天大学 | A kind of compact Wide stop bands high selectivity microstrip filter |
| CN106921012B (en) * | 2017-03-18 | 2019-03-26 | 深圳市景程信息科技有限公司 | Highly selective double frequency band-pass filter |
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2017
- 2017-03-18 CN CN201710162778.6A patent/CN106921012B/en not_active Expired - Fee Related
- 2017-10-21 WO PCT/CN2017/107192 patent/WO2018171179A1/en active Application Filing
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|---|---|---|---|---|
| CN105449323A (en) * | 2016-01-11 | 2016-03-30 | 北京邮电大学 | Planar double-frequency filter with independently adjustable frequency band |
| CN206673067U (en) * | 2017-03-18 | 2017-11-24 | 深圳市景程信息科技有限公司 | Double frequency band-pass filter based on open-circuited load and short circuit load |
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| Publication number | Publication date |
|---|---|
| WO2018171179A1 (en) | 2018-09-27 |
| CN106921012A (en) | 2017-07-04 |
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