CN217691593U - Dual-passband adjustable filter attenuator based on graphene - Google Patents
Dual-passband adjustable filter attenuator based on graphene Download PDFInfo
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- CN217691593U CN217691593U CN202221510260.XU CN202221510260U CN217691593U CN 217691593 U CN217691593 U CN 217691593U CN 202221510260 U CN202221510260 U CN 202221510260U CN 217691593 U CN217691593 U CN 217691593U
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Abstract
The utility model belongs to the technical field of electronic information, a dual-passband adjustable filter attenuator based on graphene is disclosed, which comprises a lossy medium layer, wherein a metal ground plate is arranged on one side of the lossy medium layer, and an input microstrip line, an output microstrip line, a first three-mode resonator and a second three-mode resonator are arranged on the other side of the lossy medium layer; an input port is arranged at one end of the input microstrip line, and an output port is arranged at one end of the output microstrip line; the input microstrip line and the output microstrip line are arranged at intervals, a coupling interval is formed between the input microstrip line and the output microstrip line, and the first three-mode resonator and the second three-mode resonator are arranged in the coupling interval at intervals; the first three-mode resonator and the second three-mode resonator respectively comprise three open-circuit branches and a short-circuit branch, a graphene film resistor is arranged between every two adjacent open-circuit branches, and a metal connecting piece connected with a metal grounding plate is arranged on each short-circuit branch. The dual-passband adjustable filter attenuator realizes independent adjustment of two passbands, has a simple structure and is easy to integrate and process.
Description
Technical Field
The utility model belongs to the technical field of electronic information, a dual passband adjustable filter attenuator based on graphite alkene is related to.
Background
With the development of modern microwave devices, versatility and high integration attract more and more attention. The versatility of microwave devices is an effective way to reduce circuit size and enhance versatility. In the modern microwave systems group, tunable microwave attenuators and band pass filters are important components in modern communication systems, the former for adjusting signals to different levels, and the latter being almost the most widely used microwave devices in modern microwave systems. In this case, the band pass filter and attenuator are widely used in combination in certain specific applications, including automatic level or gain control circuits in communication and radar systems.
In a microwave frequency band, one of the remarkable characteristics of graphene is that the surface impedance of graphene can be changed through electric tuning, so that the possibility of applying the graphene to an adjustable microwave device and a circuit is provided for the graphene, a plurality of scholars have studied on the filtering attenuator based on the graphene in recent years, and some feasible structures and design methods are provided, so that the design of the adjustable filtering attenuator with a single passband is realized. However, with the requirement of high integration of circuit size, in the circuit design using a plurality of single-channel adjustable filter attenuators, the number of single-channel adjustable filter attenuators is large, which results in large circuit size and complex structure, and brings more circuit loss.
SUMMERY OF THE UTILITY MODEL
The utility model aims to overcome above-mentioned prior art, in the circuit design who adopts a plurality of single channel adjustable filter attenuator, because single channel adjustable filter attenuator's a great quantity, and then lead to the circuit size great to circuit structure is complicated, therefore can bring more circuit loss's shortcoming, provides a dual passband adjustable filter attenuator based on graphite alkene.
In order to achieve the above purpose, the utility model adopts the following technical scheme to realize:
a graphene-based dual-passband adjustable filter attenuator comprises a lossy dielectric layer, wherein a metal grounding plate is arranged on one side of the lossy dielectric layer, and an input microstrip line, an output microstrip line, a first three-mode resonator and a second three-mode resonator are arranged on the other side of the lossy dielectric layer;
an input port is arranged at one end of the input microstrip line, and an output port is arranged at one end of the output microstrip line; the input microstrip line and the output microstrip line are arranged at intervals, a coupling interval is formed between the input microstrip line and the output microstrip line, and the first three-mode resonator and the second three-mode resonator are arranged in the coupling interval at intervals; the first three-mode resonator and the second three-mode resonator respectively comprise three open-circuit branches and a short-circuit branch, a graphene film resistor is arranged between every two adjacent open-circuit branches, and the side wall of each graphene film resistor is tightly attached to the side wall of the adjacent open-circuit branch; and the short circuit branch is provided with a metal connecting piece connected with the metal grounding plate.
Optionally, the lengths of the three open-circuit branches of the first three-mode resonator or the second three-mode resonator are all the same and are all one quarter of the wavelength of the electromagnetic wave to be filtered; the electrical length of the short circuit branch is 3-5 degrees.
Optionally, among the three open-circuit branches of the first or second three-mode resonator, the open-circuit branches at two sides are symmetrically bent, and the input microstrip line and the output microstrip line are arranged in parallel.
Optionally, internal devices of the first or second three-mode resonators are symmetrically distributed about the short-circuit stub.
Optionally, the graphene film resistor further comprises an external voltage source, wherein the external voltage source is connected with the graphene film resistor and is used for providing variable external voltage for the graphene film resistor.
Optionally, the SMA engine further includes an input SMA port and an output SMA port; the input SMA port is connected with the input port, and the output SMA port is connected with the output port.
Optionally, the graphene sheet resistor is square or circular in shape.
Optionally, the dielectric substrate of the lossy dielectric layer is Rogers RO4003 or Rogers RO5880; the metal grounding plate is a metal electroplating film made of silver, copper or aluminum.
Optionally, the metal connecting piece is a metal through hole or a metal cylinder.
Compared with the prior art, the utility model discloses following beneficial effect has:
the utility model discloses dual passband adjustable filter attenuator based on graphite alkene adopts first three mode syntonizers and the three mode syntonizers of second to realize the dual passband filtering, compares in the structure of a plurality of resonant cavity couplings and saves space, and the volume is littleer. And moreover, the filtering attenuator is realized through the graphene film resistor, the welding of lumped resistors is avoided, the manufacturing cost is reduced, and meanwhile, the controllability of the surface resistance of the graphene film resistor is realized through an external voltage mode, so that the attenuation of the filter is adjustable. Meanwhile, the two passbands of the filter are connected in parallel through the input microstrip line and the output microstrip line, and the two passbands are arranged at intervals and can not interfere with each other, so that the attenuation of the two passbands of the filter is independently adjustable. According to the graphene-based dual-passband adjustable filter attenuator, a dual-passband filter and an adjustable attenuator are combined together, the versatility and the high integration degree of a microwave device are realized, the circuit structure is simplified, the circuit size is reduced, the processing and the realization are easy, and an automatic level or gain control circuit in a communication and radar system has great potential application.
Drawings
Fig. 1 is a schematic view of a two-passband adjustable filter attenuator in a top view according to the present invention;
fig. 2 is a schematic side view of the dual-passband adjustable filter attenuator based on graphene according to the present invention;
fig. 3 is a schematic top view of a first three-mode resonator according to the present invention;
fig. 4 is a schematic diagram of an equivalent circuit of a dual-passband adjustable filter attenuator based on graphene according to the present invention;
fig. 5 is the utility model discloses a bi-pass band adjustable filter attenuator S parameter result sketch map under graphite alkene film resistor' S different resistances based on graphite alkene.
Wherein: 11-first open circuit branch; 12-second open circuit minor matters; 13-third open branch knot; 14-short circuit branch; 2-graphene sheet resistance; 3-a lossy dielectric layer; 4-a metal connector; 51-a first three-mode resonator; 52-a second third mode resonator; 61-input port; 62-output port; 71-input microstrip line; 72-an output microstrip line; 8-metal ground plate.
Detailed Description
In order to make the technical solution of the present invention better understood, the technical solution of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by a person skilled in the art without creative efforts shall fall within the protection scope of the present invention.
It should be noted that the terms "first," "second," and the like in the description and claims of the present invention and in the drawings described above are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It is to be understood that the data so used is interchangeable under appropriate circumstances such that the embodiments of the invention described herein are capable of operation in sequences other than those illustrated or otherwise described herein. Furthermore, the terms "comprises," "comprising," and "having," and any variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements expressly listed, but may include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus.
The present invention will be described in further detail with reference to the accompanying drawings:
referring to fig. 1 to 3, in an embodiment of the present invention, a dual-passband adjustable filter attenuator based on graphene is provided, which realizes independent and adjustable two passbands, has a simple structure, is easy to be integrated and processed, can be used in the filter design of modern communication system, and can realize the versatility and high integration of microwave devices.
Specifically, the graphene-based dual-passband adjustable filter attenuator comprises a lossy dielectric layer 3, wherein a metal ground plate 8 is arranged on one side of the lossy dielectric layer 3, an input microstrip line 71, an output microstrip line 72, a first three-mode resonator 51 and a second three-mode resonator 52 are arranged on the other side of the lossy dielectric layer, an input port 61 is arranged at one end of the input microstrip line 71, and an output port 62 is arranged at one end of the output microstrip line 72; the input microstrip line 71 and the output microstrip line 72 are arranged at intervals, a coupling interval is formed between the input microstrip line 71 and the output microstrip line 72, and the first three-mode resonator 51 and the second three-mode resonator 52 are arranged in the coupling interval at intervals; the first three-mode resonator 51 and the second three-mode resonator 52 both comprise three open-circuit branches and a short-circuit branch 14, a graphene thin-film resistor 2 is arranged between every two adjacent open-circuit branches, and the side wall of the graphene thin-film resistor 2 is tightly attached to the side wall of the adjacent open-circuit branch; the short circuit branch section 14 is provided with a metal connecting piece 4 connected with the metal grounding plate 8.
The graphene film resistor 2 is made of a two-dimensional carbon material, has excellent flexibility and conductivity, has negligible surface reactance in a microwave frequency range and dominant surface resistance, and can realize the controllability of the surface resistance in an external voltage mode, so that the attenuation of the filter can be adjusted.
Specifically, the utility model discloses dual passband adjustable filter attenuator based on graphite alkene adopts first three mode syntonizers 51 and second three mode syntonizers 52 to realize the dual passband filtering, compares in the structure of a plurality of resonant cavity couplings and saves space, and the volume is littleer. In addition, the filtering attenuator is realized through the graphene film resistor 2, welding of lumped resistors is avoided, manufacturing cost is reduced, and meanwhile, the surface resistance of the graphene film resistor 2 is controllable in an external voltage mode, so that attenuation of the filter is adjustable. Meanwhile, the two pass bands of the filter are connected in parallel through the input microstrip line 71 and the output microstrip line 72, and the two pass bands can be arranged at intervals without mutual interference, so that the two pass bands of the filter are independently adjustable in attenuation. The graphene-based dual-passband adjustable filter attenuator combines a dual-passband filter and an adjustable attenuator together, realizes the versatility and high integration of a microwave device, simplifies the circuit structure, reduces the circuit size, is easy to process and realize, and has great potential application in automatic level or gain control circuits in communication and radar systems.
In a possible embodiment, each of the first and second three- mode resonators 51 and 52 includes four metal branches, including three open-circuit branches with a quarter wavelength, which are the first open-circuit branch 11, the second open-circuit branch 12, the third open-circuit branch 13, and the shorter short-circuit branch 14, where the length of the short-circuit branch 14 affects the passband bandwidth, and the electrical length of the short-circuit branch 14 in this embodiment is about 3 ° to 5 ° for adjusting the bandwidth, where the electrical length is the ratio of the physical length of the microstrip transmission line to the wavelength of the transmitted electromagnetic wave, and the short-circuit branch 14 implements short circuit through the metal connecting member 4 communicated with the bottom metal ground plate 8, and optionally, the metal connecting member 4 is a metal through hole or a metal cylinder, and the short-circuit branch 14 can select one metal connecting member 4 according to the branch width.
In a possible embodiment, of the three open-circuit branches of the first or second third- mode resonator 51 or 52, the open-circuit branches on both sides are symmetrically bent, and the input microstrip line 71 and the output microstrip line 72 are arranged in parallel. Specifically, the first three-mode resonator 51 or the second three-mode resonator 52 bends two symmetrical open-circuit branches, that is, the first open-circuit branch 11 and the third open-circuit branch 13, so that the first three-mode resonator 51 and the second three-mode resonator 52 can be coupled by the same pair of parallel input microstrip line 71 and output microstrip line 72, and the external coupling structure becomes very simple; graphene film resistors 2 are added between the bent first open-circuit branch 11 and the bent third open-circuit branch 13 and the middle second open-circuit branch 12, and the external voltage of the graphene film resistors 2 is changed to change the resistance of the graphene film resistors 2, so that the attenuation of the filter attenuator is adjustable.
The two pass bands of the dual-band adjustable filter attenuator are coupled with the output micro-strip line 72 in a double-path mode through the input micro-strip line 71, so that the attenuation of the two pass bands is independently adjustable, but the input micro-strip line 71 and the output micro-strip line 72 are not limited to be arranged in parallel, and the rest parts of the input micro-strip line 71 and the output micro-strip line 72 can be bent under the condition that the input coupling of the first three-mode resonator 51 and the second three-mode resonator 52 is met.
In a possible implementation, the internal devices of the first or second three- mode resonators 51 and 52 are symmetrically distributed about the short-circuit branch 14. Specifically, the whole first three-mode resonator 51 or the whole second three-mode resonator 52 is symmetrical about the short-circuit stub 14, and the first three-mode resonator 51 or the second three-mode resonator 52 has three resonance points through the odd-even mode analysis, so that different resonance frequencies can be realized by changing the lengths of the stubs, and different pass bands can be realized by the first three-mode resonator 51 or the second three-mode resonator 52.
In a possible embodiment, the open branches of the first three-mode resonator 51 and the second three-mode resonator 52 may be bent according to actual requirements to make the filter structure more compact, and the widths of the branches of the first three-mode resonator 51 and the second three-mode resonator 52 may be changed according to actual situations.
In a possible implementation manner, the device further comprises an external voltage source, wherein the external voltage source is connected with the graphene thin-film resistor 2 and is used for providing a variable external voltage for the graphene thin-film resistor 2. Variable external voltage is provided for the graphene film resistor 2 by setting an external voltage source, and then the resistance of the graphene film resistor 2 is changed.
In one possible embodiment, the system further comprises an input SMA port and an output SMA port; the input SMA port is connected with the input port 61, the output SMA port is connected with the output port 62, the input port 61 and the output port 62 are located on the side face of the lossy medium layer 3, and the input SMA port and the input port 61 as well as the output SMA port and the output port 62 can be connected in a welding mode.
In a possible implementation manner, the graphene sheet resistor 2 functions to affect the impedance of the microstrip line and attenuate the electromagnetic wave transmitted in the microstrip line, and the shape of the graphene sheet resistor 2 may be any shape such as a square shape or a circular shape on the basis of meeting the design requirement.
In a possible embodiment, the dielectric substrate of the lossy dielectric layer 3 can be a dielectric with any dielectric constant, and when selecting the dielectric, the substrate with a large dielectric constant can make the model size smaller, the loss with a small loss angle is smaller but the dielectric plate is more expensive, for example, rogers RO4003 can be adopted, and Rogers RO5880 can be selected to reduce the loss. The metal microstrip line and the metal grounding plate 8 can be made of metal plating films made of any materials according to actual requirements, the common metal materials are silver, copper or aluminum, the conductivity is sequentially reduced, and the cost is also sequentially reduced.
The utility model discloses dual passband adjustable filter attenuator based on graphite alkene, the equivalent circuit diagram of loading graphite alkene film resistor's single syntonizer 5 in the example is shown in FIG. 4, and graphite alkene film resistor 2 equivalence is parallelly connected at the variable resistance on both sides of microstrip line, and resistance is less, and microstrip line transmission's electromagnetic wave is less more, and signal attenuation is big more to realize that resistance value changes the control signal level attenuation and changes.
The utility model discloses dual passband adjustable filter attenuator's working process based on graphite alkene is as follows:
after an input signal enters the dual-passband adjustable filter attenuator from the input port 61, the input signal is coupled to the first three-mode resonator 51 and the second three-mode resonator 52 through the input microstrip line 71, and due to the filtering characteristics of the three-mode resonators, only two electromagnetic signals with frequencies in the two passbands can be transmitted through the dual-passband adjustable filter attenuator, so that dual-passband filtering is realized. When the external voltage is 0V, the resistance value of the graphene thin-film resistor 2 is the largest, and the graphene thin-film resistor 2 is connected into the resonator in parallel, so that the signal can pass through the two pass bands almost completely without attenuation. When the external voltage is increased, the resistance value of the graphene film resistor 2 is reduced, and the signal attenuation is increased, so that the adjustable attenuation of the dual-passband filter is realized. Meanwhile, because the mutual influence of the two pass bands of the dual-pass-band adjustable filter attenuator is very small, when the external voltage of the graphene film resistors 2 on the two three-mode resonators is controlled respectively, the attenuation of the two pass bands of the dual-pass-band adjustable filter attenuator can be controlled respectively.
Referring to fig. 5, showing the utility model discloses dual passband adjustable filter attenuator based on graphite alkene, adopt the equivalent circuit that fig. 4 shows after the simulation test, the S parameter result of the dual passband adjustable filter attenuator who obtains, wherein, the lines of taking the triangle-shaped mark are dual passband adjustable filter attenuator 'S when graphene sheet resistance 2' S surface resistance is 70 omega and 300 omega (70 omega is 1.2GHz passband, 300 omega is 2.1GHz passband), the lines of taking the square mark are dual passband adjustable filter attenuator 'S when graphene sheet resistance 2' S surface resistance is 150 omega and 600 omega S parameter result, the lines of taking the circular mark are dual passband adjustable filter attenuator 'S when graphene sheet resistance 2' S surface resistance is 300 omega and 1200 omega S parameter result.
It can be seen that in two passbands of 1.2-1.3 GHz and 2-2.2 GHz, the S21 parameter of the dual-passband adjustable filter attenuator is attenuated continuously along with the reduction of the sheet resistance of the graphene, so that the attenuation from-3 dB to-10 dB is realized; the return loss S11 is continuously increased along with the increase of attenuation, but is less than-10 dB in the bandwidth, and the adjustable attenuation of the dual-passband filter is realized.
The above contents are only for explaining the technical idea of the present invention, and the protection scope of the present invention cannot be limited thereby, and any modification made on the basis of the technical solution according to the technical idea of the present invention all fall within the protection scope of the claims of the present invention.
Claims (9)
1. A dual-passband adjustable filter attenuator based on graphene is characterized by comprising a lossy dielectric layer (3), wherein a metal grounding plate (8) is arranged on one side of the lossy dielectric layer (3), and an input microstrip line (71), an output microstrip line (72), a first three-mode resonator (51) and a second three-mode resonator (52) are arranged on the other side of the lossy dielectric layer;
an input port (61) is arranged at one end of the input microstrip line (71), and an output port (62) is arranged at one end of the output microstrip line (72); the input microstrip line (71) and the output microstrip line (72) are arranged at intervals, a coupling interval is formed between the input microstrip line (71) and the output microstrip line (72), and the first three-mode resonator (51) and the second three-mode resonator (52) are arranged in the coupling interval at intervals; the first three-mode resonator (51) and the second three-mode resonator (52) respectively comprise three open-circuit branches and a short-circuit branch (14), a graphene thin film resistor (2) is arranged between every two adjacent open-circuit branches, and the side wall of the graphene thin film resistor (2) is tightly attached to the side wall of the adjacent open-circuit branch; and the short circuit branch knot (14) is provided with a metal connecting piece (4) connected with the metal grounding plate (8).
2. The graphene-based dual-passband adjustable filter attenuator according to claim 1, wherein the three open-circuit branches of the first mode resonator (51) or the second mode resonator (52) are all the same in length and are all one quarter of the wavelength of the electromagnetic wave to be filtered; the electrical length of the short circuit branch (14) is 3-5 degrees.
3. The graphene-based dual-passband adjustable filter attenuator according to claim 1, wherein the open-circuit branches at two sides of the three open-circuit branches of the first three-mode resonator (51) or the second three-mode resonator (52) are symmetrically bent, and the input microstrip line (71) and the output microstrip line (72) are arranged in parallel.
4. The graphene-based dual-passband adjustable filter attenuator according to claim 1, wherein the internal devices of the first or second three-mode resonators (51, 52) are symmetrically distributed about the shorting stub (14).
5. The graphene-based dual-passband adjustable filter attenuator according to claim 1, further comprising an external voltage source, wherein the external voltage source is connected to the graphene thin film resistor (2) and is configured to provide a variable external voltage to the graphene thin film resistor (2).
6. The graphene-based dual-passband adjustable filter attenuator according to claim 1, further comprising an input SMA port and an output SMA port; the input SMA port is connected to the input port (61), and the output SMA port is connected to the output port (62).
7. The graphene-based dual-passband adjustable filter attenuator according to claim 1, wherein the graphene sheet resistor (2) is square or circular in shape.
8. The graphene-based dual-passband adjustable filter attenuator according to claim 1, wherein the dielectric substrate of the lossy dielectric layer (3) is Rogers RO4003 or Rogers RO5880; the metal grounding plate (8) is a metal electroplating film made of silver, copper or aluminum.
9. The graphene-based dual-passband adjustable filter attenuator according to claim 1, wherein the metal connecting pieces (4) are metal through holes or metal cylinders.
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| Application Number | Priority Date | Filing Date | Title |
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| CN202221510260.XU CN217691593U (en) | 2022-06-16 | 2022-06-16 | Dual-passband adjustable filter attenuator based on graphene |
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| CN202221510260.XU CN217691593U (en) | 2022-06-16 | 2022-06-16 | Dual-passband adjustable filter attenuator based on graphene |
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| CN202221510260.XU Active CN217691593U (en) | 2022-06-16 | 2022-06-16 | Dual-passband adjustable filter attenuator based on graphene |
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