CN106898848A - A kind of ultra-wide stop-band low-pass filter of H types open circuit minor matters combination palisading type defect ground structure - Google Patents
A kind of ultra-wide stop-band low-pass filter of H types open circuit minor matters combination palisading type defect ground structure Download PDFInfo
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- CN106898848A CN106898848A CN201710190221.3A CN201710190221A CN106898848A CN 106898848 A CN106898848 A CN 106898848A CN 201710190221 A CN201710190221 A CN 201710190221A CN 106898848 A CN106898848 A CN 106898848A
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- minor matters
- open circuit
- palisading type
- ground structure
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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
- H01P1/2005—Electromagnetic photonic bandgaps [EPB], or photonic bandgaps [PBG]
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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
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- Electromagnetism (AREA)
- Optics & Photonics (AREA)
- Control Of Motors That Do Not Use Commutators (AREA)
Abstract
The present invention relates to a kind of ultra-wide stop-band low-pass filter of H types open circuit minor matters combination palisading type defect ground structure, ultra-wide stop-band low-pass filter needed for radio system can be realized, there is broader stopband compared to traditional DGS wave filters, with preferable degree of roll-offing, and in practical application, based on this design, the microwave filter of small volume can be produced, so as to improve the integrated level of radio-frequency devices and system.
Description
Technical field
The present invention relates to a kind of ultra-wide stop-band low-pass filter of H types open circuit minor matters combination palisading type defect ground structure, category
In Electromagnetic Field and Microwave Technology field.
Background technology
In wireless telecommunication system, microwave filter as a kind of crucial radio-frequency devices with frequency selector, its
The quality of performance decides the quality of whole system communication quality, also can to a certain extent restrict the hair of wireless telecommunication system
Exhibition.Therefore, high-performance, the research of the wave filter of miniaturization are all the time a research emphasis.Lacking with band gap properties
Fall into ground structure（DGS）Possess huge application value in terms of performance of filter is improved, attract the wide of domestic and international researcher
General concern.There is the performance of many uniquenesses, such as single pole and low pass characteristic, Slow-wave effect, with higher feature just because of DGS
Impedance etc. so as to studying as a new study hotspot in microwave circuits for DGS.
In recent years, emerged in an endless stream using the document of defect ground structure design low pass filter, but traditional dumbbell structure
Defect ground（DGS）Intermediate zone decline is shallower, and selectivity is bad, and the overall volume of its microwave device is also than larger, DGS structure lists
The low pass filter stopband that the cycle simple cascade of unit is constituted is not wide enough, it is impossible to effectively suppress higher harmonics, and simply
Level joint conference causes the area of wave filter larger, and uses multilayer technique, there are processing difficulties.
The content of the invention
The technical problems to be solved by the invention are to provide one kind using H-shaped open circuit minor matters, by cascading lateral dimension not
Same palisading type defect ground structure, can realize that the H types open circuit minor matters of ultra-wide stop-band low-pass filter needed for radio system are combined
The ultra-wide stop-band low-pass filter of palisading type defect ground structure.
In order to solve the above-mentioned technical problem the present invention uses following technical scheme：The present invention devises a kind of H types open circuit branch
Nodule closes the ultra-wide stop-band low-pass filter of palisading type defect ground structure, including medium substrate, ground metal layer, straight line shaped microstrip
Transmission line, at least three open circuits minor matters line and at least two groups palisading type defect ground structures；Wherein, ground metal layer covering is arranged at
The back side of medium substrate, linear microstrip transmission line is arranged on the front of medium substrate, and linear microstrip transmission line two
End connects with the front edge of medium substrate respectively；Each open circuit minor matters line is respectively arranged on the front of medium substrate, straight line
Midpoint of the shaped microstrip transmission line successively with each open circuit minor matters line is connected, and each open circuit minor matters line is transmitted with straight line shaped microstrip respectively
Line is perpendicular, and keeps default spacing between adjacent open circuit minor matters line；The quantity of palisading type defect ground structure is open circuit minor matters line
Quantity subtract one, each group palisading type defect ground structure respectively it is adjacent with each open circuit minor matters line between gap correspond, each group
Palisading type defect ground structure includes two sub- palisading type ground structures and a connecting line construction, each group palisading type defect ground structure respectively
In sub- palisading type ground structure and connecting line construction be respectively positioned in ground metal layer, and by the etching reality for ground metal layer
It is existing；Using the direction perpendicular to surface where medium substrate as projecting direction is referred to, on reference projecting direction, each group palisading type
In defect ground structure two projected positions of sub- palisading type ground structure be located at respectively between the adjacent open circuit minor matters line of correspondence in gap,
Two sub- palisading type ground structures in the both sides of linear microstrip transmission line, and each group palisading type defect ground structure are with reference to projection
On direction with linear microstrip transmission line as axle axisymmetricly, and with reference on projecting direction, each sub- palisading type ground structure
Edge relative with the edge at the edge of corresponding linear microstrip transmission line around it, open circuit minor matters line respectively connect；Each group grid
Connecting line construction in column type defect ground structure is located between two sub- palisading type ground structures of correspondence, and the two ends of connecting line construction are distinguished
Relative with two sub- palisading type ground structures of correspondence to connect, straight line where connecting line construction mutually hangs down with straight line where linear microstrip transmission line
Directly.
As a preferred technical solution of the present invention：Spacing between described each adjacent open circuit minor matters line, along linear
Straight line where microstrip transmission line is incremented by successively.
As a preferred technical solution of the present invention：In each open circuit minor matters line, passed along the straight line shaped microstrip
In thread transferring direction, the width of two open circuit minor matters lines of head and the tail is respectively less than the width of middle any one open circuit minor matters line.
As a preferred technical solution of the present invention：In each open circuit minor matters line, passed along the straight line shaped microstrip
In thread transferring direction, the width of two open circuit minor matters lines of head and the tail is equal to each other, and the width of middle each open circuit minor matters line is equal to each other.
As a preferred technical solution of the present invention：The quantity of the open circuit minor matters line is four.
A kind of ultra-wide stop-band low-pass filter of H types open circuit minor matters combination palisading type defect ground structure of the present invention is used
Above technical scheme compared with prior art, with following technique effect：The H types open circuit minor matters combination palisading type of present invention design
The ultra-wide stop-band low-pass filter of defect ground structure, can realize ultra-wide stop-band low-pass filter needed for radio system, compared to biography
System DGS wave filters have broader stopband, with preferable degree of roll-offing, and in practical application, based on this design, can manufacture
Go out the microwave filter of small volume, so as to improve the integrated level of radio-frequency devices and system.
Brief description of the drawings
Fig. 1 is the ultra-wide stop-band low-pass filter of H types open circuit minor matters combination palisading type defect ground structure designed by the present invention
Front schematic view；
Fig. 2 is the back of the body of the ultra-wide stop-band low-pass filter of H types open circuit minor matters combination palisading type defect ground structure designed by the present invention
Face schematic diagram.
Wherein, 1. medium substrate, 2. ground metal layer, 3. linear microstrip transmission line, minor matters line of 4. opening a way, 5.
Palisading type defect ground structure, 6. sub- palisading type ground structure, 7. connecting line construction.
Specific embodiment
Specific embodiment of the invention is described in further detail with reference to Figure of description.
As depicted in figs. 1 and 2, the present invention devises a kind of ultra-wide of H types open circuit minor matters combination palisading type defect ground structure
Stop-band low-pass filter, in actual applications, specifically include medium substrate 1, ground metal layer 2, linear microstrip transmission line 3,
At least three open circuit minor matters lines 4 and at least two groups palisading type defect ground structures 5；Wherein, the covering of ground metal layer 2 is arranged at medium
The back side of substrate 1, linear microstrip transmission line 3 is arranged on the front of medium substrate 1, and linear microstrip transmission line 3 two
The front edge respectively with medium substrate 1 is held to connect；Each open circuit minor matters line 4 is respectively arranged on the front of medium substrate 1, directly
Midpoint of the linear microstrip transmission line 3 successively with each open circuit minor matters line 4 is connected, and each open circuit minor matters line 4 is micro- with linear respectively
Band transmission line 3 is perpendicular, and keeps default spacing between adjacent open circuit minor matters line 4；The quantity of palisading type defect ground structure 5 is to open
The quantity of road minor matters line 4 subtracts one, the gap one between open circuit minor matters line 4 adjacent with each respectively of each group palisading type defect ground structure 5
One correspondence, each group palisading type defect ground structure 5 includes two sub- palisading type ground structures 6 and a connecting line construction 7, each group grid respectively
Sub- palisading type ground structure 6 and connecting line construction 7 in column type defect ground structure 5 are respectively positioned in ground metal layer 2, and by being directed to
The etching of ground metal layer 2 is realized；Using the direction perpendicular to the place surface of medium substrate 1 as projecting direction is referred to, in reference
On projecting direction, two projected positions of sub- palisading type ground structure 6 are located at correspondence phase respectively in each group palisading type defect ground structure 5
Between neighbour's open circuit minor matters line 4 in gap, in the both sides of linear microstrip transmission line 3, and each group palisading type defect ground structure 5 two
Individual sub- palisading type ground structure 6 with reference on projecting direction with linear microstrip transmission line 3 be axle axisymmetricly, and with reference to throwing
On shadow direction, each edge of sub- palisading type ground structure 6 respectively the edge of linear microstrip transmission line 3 corresponding with around it,
The edge of open circuit minor matters line 4 is relative to be connect；Connecting line construction 7 in each group palisading type defect ground structure 5 is located at two sub- fence of correspondence
Between type ground structure 6, and connecting line construction 7 two ends it is relative with two sub- palisading type ground structures 6 of correspondence respectively connect, connecting line construction 7
Place straight line is perpendicular with the place straight line of linear microstrip transmission line 3.
On the basis of above-mentioned designed technical scheme, in the middle of actual application, specifically designed as follows, for opening
The quantity of road minor matters line 4, is set as four；Spacing between each adjacent open circuit minor matters line 4, along the institute of linear microstrip transmission line 3
It is incremented by successively in straight line；In each open circuit minor matters line 4, along the direction of linear microstrip transmission line 3, two open circuit branches of head and the tail
The width of nodel line 4 is equal to each other, and the width of middle two open circuit minor matters line 4 is equal to each other, and two open circuit minor matters lines 4 of head and the tail
Width be respectively less than the width of middle any one open circuit minor matters line 4.
The present invention devises a kind of ultra-wide stop-band low-pass filter of H types open circuit minor matters combination palisading type defect ground structure,
In actual applications, as depicted in figs. 1 and 2, each group palisading type defect ground structure 5 includes two sub- palisading type ground structures 6 respectively
With a connecting line construction 7, specifically, each sub- palisading type ground structure 6 is respectively by lateral etching region and longitudinal etch areas
Composition, each group palisading type defect ground structure 5 can be simple in parallel with Approximate Equivalent as oneLCResonance circuit,LWithCRepresent fence
The inductance and electric capacity of type defect ground structure 5 itself, in each group palisading type defect ground structure 5, transmit positioned at straight line shaped microstrip respectively
Two area equivalents of sub- palisading type ground structure 6 of the line about 3 are inductance, and its value is horizontal with two sub- palisading type ground structures 6
The number and lateral etching peak width of etch areas are directly proportional；Two connecting line constructions 7 of sub- palisading type ground structure 6 of centre connection
An electric capacity can be then equivalent to, its size is inversely proportional with the width of connecting line construction 7.The physics chi of each group palisading type defect ground structure 5
Very little change can influence the frequency of fadings of linear microstrip transmission line 3, in order to the with needed for realizing hinders characteristic, can be by appropriate
The length in the lateral etching region of the neutron palisading type ground structure 6 of regulation each group palisading type defect ground structure 5 and number or longitudinal direction
The size for etching width obtains required resonant frequency, i.e., the length in lateral etching region subtracts in group palisading type ground structure 6
When small or number reduces, its frequency of fadings can increase therewith；The longitudinal direction etching in lateral etching region in sub- palisading type ground structure 6
When width increases, its frequency of fadings can reduce therewith.
In practical application, the width of specific design linear microstrip transmission line 3 is the length of 1.8mm, length and medium substrate 1
Degree is identical, to obtain 50 ohm of characteristic impedance；The open circuit minor matters line 4 at the two ends of each group palisading type defect ground structure 5 is carried in, is
In order to strengthen the coupled capacitor between linear microstrip transmission line 3 and each group palisading type defect ground structure 5, so as to further expand
The bandwidth of rejection of each group palisading type defect ground structure 5.
The present invention devises a kind of ultra-wide stop-band low-pass filter of H types open circuit minor matters combination palisading type defect ground structure,
Microelectronic technique, laser technology or printed circuit technology can be used in manufacturing process.Wherein, ground metal layer 2, linear
Microstrip transmission line 3, at least three open circuit minor matters lines 4 and at least two groups palisading type defect ground structures 5 are all good by electric conductivity
Conductor material is constituted；It is 3.55 that medium substrate 1 can use dielectric constant, and thickness of dielectric layers is the two-sided deposited copper coin of 0.8mm
（Rogers RO4003）.
To sum up, the ultra-wide stop-band low-pass filter of the designed H types open circuit minor matters combination palisading type defect ground structure of the present invention,
Ultra-wide stop-band low-pass filter needed for radio system can be realized, there is broader stopband compared to traditional DGS wave filters, with compared with
Good degree of roll-offing, and in practical application, based on this design, the microwave filter of small volume can be produced, so as to improve penetrate
The integrated level of frequency device and system.
Embodiments of the present invention are explained in detail above in conjunction with accompanying drawing, but the present invention is not limited to above-mentioned implementation
Mode, in the ken that those of ordinary skill in the art possess, can also be on the premise of present inventive concept not be departed from
Make a variety of changes.
Claims (5)
1. a kind of H types are opened a way the ultra-wide stop-band low-pass filter of minor matters combination palisading type defect ground structure, it is characterised in that：Including
Medium substrate（1）, ground metal layer（2）, linear microstrip transmission line（3）, at least three open circuit minor matters lines（4）At least two groups
Palisading type defect ground structure（5）；Wherein, ground metal layer（2）Covering is arranged at medium substrate（1）The back side, straight line shaped microstrip
Transmission line（3）It is arranged at medium substrate（1）Front on, and linear microstrip transmission line（3）Two ends respectively with medium substrate
（1）Front edge connect；Each open circuit minor matters line（4）It is respectively arranged at medium substrate（1）Front on, straight line shaped microstrip pass
Defeated line（3）Successively with each open circuit minor matters line（4）Midpoint be connected, each open circuit minor matters line（4）Passed with straight line shaped microstrip respectively
Defeated line（3）It is perpendicular, and adjacent open circuit minor matters line（4）Between keep default spacing；Palisading type defect ground structure（5）Quantity be
Open circuit minor matters line（4）Quantity subtract one, each group palisading type defect ground structure（5）Respectively it is adjacent with each open circuit minor matters line（4）It
Between gap correspond, each group palisading type defect ground structure（5）Include two sub- palisading type ground structures respectively（6）With a line
Structure（7）, each group palisading type defect ground structure（5）In sub- palisading type ground structure（6）And connecting line construction（7）It is respectively positioned on ground connection gold
Category layer（2）On, and by for ground metal layer（2）Etching realize；With perpendicular to medium substrate（1）The side on place surface
To as projecting direction is referred to, on reference projecting direction, each group palisading type defect ground structure（5）In two sub- palisading type ground knots
Structure（6）Projected position respectively be located at correspondence it is adjacent open circuit minor matters line（4）Between in gap, linear microstrip transmission line（3）'s
Both sides, and each group palisading type defect ground structure（5）In two sub- palisading type ground structures（6）With straight line on reference projecting direction
Shaped microstrip transmission line（3）For axle axisymmetricly, and on reference projecting direction, each sub- palisading type ground structure（6）Edge
Linear microstrip transmission line corresponding with around it respectively（3）Edge, open circuit minor matters line（4）Edge relative connect；Each group grid
Column type defect ground structure（5）In connecting line construction（7）Positioned at two sub- palisading type ground structures of correspondence（6）Between, and connecting line construction
（7）Two ends respectively with corresponding two sub- palisading type ground structures（6）It is relative to connect, connecting line construction（7）Place straight line is micro- with linear
Band transmission line（3）Place straight line is perpendicular.
2. a kind of H types are opened a way the ultra-wide stopband LPF of minor matters combination palisading type defect ground structure according to claim 1
Device, it is characterised in that：Described each adjacent open circuit minor matters line（4）Between spacing, along linear microstrip transmission line（3）Place straight line
It is incremented by successively.
3. a kind of H types according to claim 1 or claim 2 are opened a way the ultra-wide stopband low pass filtered of minor matters combination palisading type defect ground structure
Ripple device, it is characterised in that：Each open circuit minor matters line（4）In, along the linear microstrip transmission line（3）On direction, head and the tail
Two open circuit minor matters lines（4）Width be respectively less than middle any one open circuit minor matters line（4）Width.
4. a kind of H types are opened a way the ultra-wide stopband LPF of minor matters combination palisading type defect ground structure according to claim 3
Device, it is characterised in that：Each open circuit minor matters line（4）In, along the linear microstrip transmission line（3）On direction, head and the tail two
Root open circuit minor matters line（4）Width be equal to each other, middle each open circuit minor matters line（4）Width be equal to each other.
5. a kind of H types are opened a way the ultra-wide stopband LPF of minor matters combination palisading type defect ground structure according to claim 4
Device, it is characterised in that：The open circuit minor matters line（4）Quantity be four.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710190221.3A CN106898848B (en) | 2017-03-28 | 2017-03-28 | A kind of ultra-wide stop-band low-pass filter of H-type open circuit minor matters combination palisading type defect ground structure |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710190221.3A CN106898848B (en) | 2017-03-28 | 2017-03-28 | A kind of ultra-wide stop-band low-pass filter of H-type open circuit minor matters combination palisading type defect ground structure |
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| CN106898848A true CN106898848A (en) | 2017-06-27 |
| CN106898848B CN106898848B (en) | 2019-01-18 |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN115513621A (en) * | 2022-09-23 | 2022-12-23 | 中国科学院物理研究所 | Microstrip graphic layer, preparation method thereof and low-pass band-pass filter thereof |
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| CN102723542A (en) * | 2012-06-14 | 2012-10-10 | 重庆大学 | Ultra-broad stopband microstrip low-pass filter |
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Cited By (2)
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| CN115513621A (en) * | 2022-09-23 | 2022-12-23 | 中国科学院物理研究所 | Microstrip graphic layer, preparation method thereof and low-pass band-pass filter thereof |
| CN115513621B (en) * | 2022-09-23 | 2023-12-15 | 中国科学院物理研究所 | Microstrip pattern layer, preparation method thereof and low pass band pass filter thereof |
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| Publication number | Publication date |
|---|---|
| CN106898848B (en) | 2019-01-18 |
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