CN111816992B - Method for realizing polarization reconfigurable antenna based on characteristic mode - Google Patents
Method for realizing polarization reconfigurable antenna based on characteristic mode Download PDFInfo
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- CN111816992B CN111816992B CN202010495383.XA CN202010495383A CN111816992B CN 111816992 B CN111816992 B CN 111816992B CN 202010495383 A CN202010495383 A CN 202010495383A CN 111816992 B CN111816992 B CN 111816992B
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- 230000010287 polarization Effects 0.000 title claims abstract description 68
- 238000000034 method Methods 0.000 title claims abstract description 23
- 239000002184 metal Substances 0.000 claims abstract description 47
- 230000005855 radiation Effects 0.000 claims abstract description 15
- 239000003990 capacitor Substances 0.000 claims description 14
- 238000005516 engineering process Methods 0.000 claims description 2
- 238000002955 isolation Methods 0.000 abstract 1
- 238000010586 diagram Methods 0.000 description 13
- 238000004891 communication Methods 0.000 description 5
- 230000009286 beneficial effect Effects 0.000 description 3
- 230000001939 inductive effect Effects 0.000 description 2
- 230000005540 biological transmission Effects 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000004088 simulation Methods 0.000 description 1
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01Q—ANTENNAS, i.e. RADIO AERIALS
- H01Q1/00—Details of, or arrangements associated with, antennas
- H01Q1/36—Structural form of radiating elements, e.g. cone, spiral, umbrella; Particular materials used therewith
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01Q—ANTENNAS, i.e. RADIO AERIALS
- H01Q1/00—Details of, or arrangements associated with, antennas
- H01Q1/50—Structural association of antennas with earthing switches, lead-in devices or lightning protectors
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01Q—ANTENNAS, i.e. RADIO AERIALS
- H01Q15/00—Devices for reflection, refraction, diffraction or polarisation of waves radiated from an antenna, e.g. quasi-optical devices
- H01Q15/24—Polarising devices; Polarisation filters
- H01Q15/242—Polarisation converters
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01Q—ANTENNAS, i.e. RADIO AERIALS
- H01Q9/00—Electrically-short antennas having dimensions not more than twice the operating wavelength and consisting of conductive active radiating elements
- H01Q9/04—Resonant antennas
- H01Q9/0407—Substantially flat resonant element parallel to ground plane, e.g. patch antenna
- H01Q9/0428—Substantially flat resonant element parallel to ground plane, e.g. patch antenna radiating a circular polarised wave
Abstract
The application relates to a method for realizing a polarization reconfigurable antenna based on a characteristic mode, which comprises the following steps: step 10, knowing a rectangular metal ring structure, and setting a midpoint A of any side of the rectangular metal ring structure and two opposite corner points B and C; step 20, setting characteristic mode current distribution corresponding to the rectangular metal ring structure; step 30, setting the side length of the rectangular metal ring structure to be a quarter wavelength of a resonance frequency point; step 40, feeding the antenna at the midpoint A; step 50, feeding power to the rectangular metal ring structure at the midpoint A; and step 60, loading single-pole double-throw switches at the corner points B and C. The invention discloses a method for realizing a polarization reconfigurable antenna based on a characteristic mode, which realizes the polarization reconfigurable antenna design of a radiation unit and realizes the radiation mode switching between left-handed rotation and linear polarization, so that the signal receiving and transmitting of different systems can be realized by one antenna through polarization isolation, and the generation of space interference is prevented.
Description
Technical Field
The application belongs to the technical field of antennas, and particularly relates to a reconfigurable antenna implementation method based on characteristic mode polarization.
Background
With the rapid development of modern radar and communication systems, more and more antennas are required for airplanes, ships, satellites and the like to achieve the purposes of communication, navigation, guidance, warning, weapon seeking and the like. This makes the weight of load on the platform constantly increase, and the expense that sets up the antenna also constantly rises moreover, and simultaneously, the electromagnetic interference between each antenna is also very big, seriously influences the normal work of antenna. In order to reduce the weight of the antenna loaded on the platform, reduce the cost, and reduce the radar cross section of the platform to achieve good electromagnetic compatibility, it is desirable to implement the functions of multiple antennas by using one antenna. The same antenna or antenna array is adopted, the physical structure or size of the antenna is dynamically changed, so that the antenna has the function of a plurality of antennas, namely, the plurality of antennas share one physical caliber, and the antenna is called as a reconfigurable antenna. As the technology is not mature, the theory of the reconfigurable antenna is still insufficient, and the reconfigurable antenna has less application in a communication system.
The reconfigurable antenna can be divided into a frequency reconfigurable antenna (including broadband realization and multiband realization), a directional diagram reconfigurable antenna, a polarization reconfigurable antenna and a multi-electromagnetic parameter reconfigurable antenna according to functions. By changing the structure of the reconfigurable antenna, one or more of various parameters such as frequency, a directional diagram, a polarization mode and the like of the antenna can be reconfigured. Therefore, the antenna can have a plurality of working modes by switching different states of the antenna, and is beneficial to realizing a plurality of effective diversities in transmission.
The polarization reconfigurable antenna can change own polarization characteristics under the condition that the working frequency and the radiation pattern are not changed, the capacity of a system is increased through frequency multiplexing, the problem of polarization mismatch in communication can be solved, and therefore the communication quality is improved. Polarization reconfigurable antennas are generally divided into three categories: switching between two linear polarizations of orthogonal polarizations; switching between two circular polarizations; switching between circular polarization and linear polarization. The main difficulty of polarization reconstruction is to maintain the frequency characteristics of the antenna stable while achieving polarization reconstruction.
Disclosure of Invention
The technical problem to be solved by the invention is as follows: the method for realizing the polarized reconfigurable antenna based on the characteristic mode aims to solve the defects of antenna functionality and stability in the prior art, and thus, the method for realizing the polarized reconfigurable antenna based on the characteristic mode is multifunctional and interference-proof.
The technical scheme adopted by the invention for solving the technical problem is as follows:
a method for realizing a polarization reconfigurable antenna based on a characteristic mode comprises the following steps:
and step 60, loading single-pole double-throw switches at the corner points B and C according to the step 40 and the step 50.
In one embodiment, in step 50:
and loading capacitors or inductors at the corner points B and C.
In one embodiment, in step 50:
when the reactance elements loaded at the corner points B and C are capacitors, left-handed circular polarization is realized; and when the reactance elements loaded at the corner points B and C are inductors, right-hand circular polarization is realized.
In one embodiment, in step 60:
according to said steps 40 and 50, single pole four throw switches are loaded at said corner points B and C.
In one embodiment, in step 40:
when the midpoint A feeds the antenna, the antenna realizes resonance at a specific frequency, and the current distribution of the resonance is the same-phase superposition result of the first characteristic mode and the second characteristic mode, so that the linear polarization radiation characteristic is realized.
In one embodiment, in step 50:
and tuning the phase of the second characteristic mode by the antenna, and when the phase of the second characteristic mode is ninety degrees different from the phase of the first characteristic mode, feeding to realize the same-frequency circularly polarized radiation characteristic.
In one embodiment, in step 20:
in the first characteristic mode, current flows out from the corner point C of the rectangular metal ring structure, passes through the other two corner points and finally flows into the corner point B.
In one embodiment, in step 20:
in the second characteristic mode, the corner points B and C of the rectangular metal ring structure are points through which current flows halfway.
In one embodiment, the rectangular metal ring structure is square.
In one embodiment, the side length of the rectangular metal ring structure is 200mm, and 8pF capacitor or 40Nh inductor is loaded at the corner points B and C.
The invention has the beneficial effects that: the invention relates to a method for realizing a polarization reconfigurable antenna based on a characteristic mode, which is based on an antenna analysis thought of the characteristic mode, utilizes two inherent same-frequency orthogonal modes of the antenna into two modes for realizing circular polarization, and realizes circular polarization radiation of a single feed radiator by loading a proper feed mode.
Drawings
The technical solution of the present application is further explained below with reference to the drawings and the embodiments.
Fig. 1 is a schematic structural diagram of a rectangular metal ring structure according to an embodiment of the present application;
FIG. 2 is a first characteristic pattern current profile of an embodiment of the present application;
FIG. 3 is a second characteristic pattern current profile of an embodiment of the present application;
FIG. 4 is a schematic diagram of a left-hand circular polarization S11 during inductive loading according to an embodiment of the present application;
FIG. 5 is a schematic diagram of left-hand circular polarization axial ratio when inductively loaded according to an embodiment of the present application;
FIG. 6 is a schematic illustration of a 0 ohm linear polarization S11 for an embodiment of the present application;
FIG. 7 is a 0 ohm linear polarization axis ratio schematic of an embodiment of the present application;
FIG. 8 is a schematic diagram of right hand circular polarization S11 when the capacitor is loaded according to an embodiment of the present application;
FIG. 9 is a schematic diagram of right hand circular polarization axial ratio when the capacitor is loaded according to an embodiment of the present application;
fig. 10 is a schematic flowchart of a method for implementing a polarization reconfigurable antenna based on a characteristic mode according to an embodiment of the present application.
Detailed Description
It should be noted that, in the present application, the embodiments and features of the embodiments may be combined with each other without conflict.
In the description of the present application, it is to be understood that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," and the like are used in the orientation or positional relationship indicated in the drawings for convenience in describing the present application and for simplicity in description, and are not intended to indicate or imply that the referenced devices or elements must have a particular orientation, be constructed in a particular orientation, and be operated in a particular manner, and are not to be considered limiting of the scope of the present application. Furthermore, the terms "first", "second", etc. are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first," "second," etc. may explicitly or implicitly include one or more of that feature. In the description of the invention, the meaning of "a plurality" is two or more unless otherwise specified.
In the description of the present application, it should be noted that, unless otherwise explicitly stated or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be, for example, a fixed connection, a detachable connection, or an integral connection; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present application can be understood by those of ordinary skill in the art through specific situations.
The technical solutions of the present application will be described in detail below with reference to the accompanying drawings in conjunction with embodiments.
Fig. 1 is a schematic structural diagram of a rectangular metal ring structure according to an embodiment of the present application; FIG. 2 is a first characteristic pattern current profile of an embodiment of the present application; FIG. 3 is a second characteristic pattern current profile of an embodiment of the present application; FIG. 4 is a schematic diagram of a left-hand circular polarization S11 during inductive loading according to an embodiment of the present application; FIG. 5 is a schematic diagram of left-hand circular polarization axial ratio when inductively loaded according to an embodiment of the present application; FIG. 6 is a schematic diagram of a 0 ohm linear polarization S11 of an embodiment of the present application; FIG. 7 is a 0 ohm linear polarization axis ratio schematic of an embodiment of the present application; FIG. 8 is a schematic diagram of right hand circular polarization S11 when capacitively loaded according to an embodiment of the present application; FIG. 9 is a schematic diagram of right hand circular polarization axial ratio when the capacitor is loaded according to an embodiment of the present application; fig. 10 is a schematic flowchart of a method for implementing a polarization reconfigurable antenna based on a characteristic mode according to an embodiment of the present application.
Referring to fig. 1 and fig. 10, a method for implementing a polarization reconfigurable antenna based on a characteristic mode includes the following steps:
In one embodiment, step 50:
and loading capacitance or inductance at corner points B and C.
In one embodiment, step 50:
when the reactance elements loaded at the corner points B and C are capacitors, left-handed circular polarization is realized; and when the reactance elements loaded at the corner points B and C are inductors, right-hand circular polarization is realized.
In one embodiment, step 60:
single pole four throw switches are loaded at corner points B and C, according to steps 40 and 50. Left and right hand circular polarization can be achieved if B, C is a capacitor and B, C is an inductor, respectively. Therefore, if a single pole four throw switch is placed at B, C, the conversion between left-handed right-handed and linear polarization can also be achieved.
In one embodiment, in step 40:
when the midpoint A feeds the antenna, the antenna realizes resonance at a specific frequency, and the current distribution of the whole resonance is the same-phase superposition result of the first characteristic mode and the second characteristic mode, so that the linear polarization radiation characteristic is realized.
In one embodiment, step 50:
and tuning the phase of the second characteristic mode, and when the phase of the second characteristic mode is ninety degrees different from the phase of the first characteristic mode, feeding to realize the same-frequency circularly polarized radiation characteristic. When the rectangular metal ring is fed at A, a specific reactance element is loaded at B, C two points, the antenna can be tuned in the phase of the second characteristic mode, and when the phase of the second characteristic mode is ninety degrees different from that of the first characteristic mode, the feeding can achieve the same-frequency circularly polarized radiation characteristic.
In one embodiment, in step 20:
in the first characteristic mode, current flows out from a corner point C of the rectangular metal ring structure, passes through the other two corner points and finally flows into the corner point B.
In one embodiment, in step 20:
in the second characteristic mode, corner points B and C of the rectangular metal ring structure are points through which current flows halfway.
In one embodiment, the rectangular metal ring structure is square.
In one embodiment, the rectangular metal ring structure has a side length of 200mm, and 8pF capacitor or 40Nh inductor is loaded at corner points B and C. For further verification, simulation results of the present embodiment are given with reference to fig. 4 to 9, in which left-hand circular polarization is achieved when the inductor is loaded at 40Nh and right-hand circular polarization is achieved when the capacitor is loaded at 8 pF.
The invention has the beneficial effects that: the invention relates to a method for realizing a polarization reconfigurable antenna based on a characteristic mode, which is based on an antenna analysis thought of the characteristic mode, utilizes two inherent same-frequency orthogonal modes of the antenna into two modes for realizing circular polarization, and realizes circular polarization radiation of a single feed radiator by loading a proper feed mode.
In light of the foregoing description of the preferred embodiments according to the present application, it is to be understood that various changes and modifications may be made by those skilled in the art without departing from the scope of the invention as defined by the appended claims. The technical scope of the present application is not limited to the contents of the specification, and must be determined according to the scope of the claims.
Claims (9)
1. A method for realizing a polarization reconfigurable antenna based on a characteristic mode is characterized by comprising the following steps:
step 10, knowing a rectangular metal ring structure, and setting a midpoint A of any side of the rectangular metal ring structure and two opposite corner points B and C;
step 20, setting a characteristic mode current distribution corresponding to the rectangular metal ring structure, wherein the characteristic mode current distribution comprises a first characteristic mode and a second characteristic mode, corner points B and C of the rectangular metal ring structure in the first characteristic mode are current maximum points, the other two corner points of the rectangular metal ring structure are current minimum points, the corner points B and C of the rectangular metal ring structure in the second characteristic mode are current minimum points, and the other two corner points of the rectangular metal ring structure are current maximum points;
step 30, setting the side length of the rectangular metal ring structure to be a quarter wavelength of a resonance frequency point, wherein the first characteristic mode and the second characteristic mode are the same frequency and orthogonal modes;
step 40, feeding the antenna at the midpoint A;
step 50, feeding the rectangular metal ring structure at the midpoint A, loading reactance elements at corner points B and C, and tuning the phase of the second characteristic mode of the antenna;
and loading a single-pole double-throw switch or a single-pole four-throw switch at the corner points B and C to switch the steps 40 and 50.
2. The implementation method of the antenna based on characteristic mode polarization reconfigurable antenna according to claim 1, characterized in that in the step 50:
and the reactance elements loaded at the corner points B and C are capacitors or inductors.
3. The implementation method of the antenna based on characteristic mode polarization reconfigurable antenna according to claim 2, characterized in that in the step 50:
when the reactance elements loaded at the corner points B and C are capacitors, left-handed circular polarization is realized; and when the reactance elements loaded at the corner points B and C are inductors, right-hand circular polarization is realized.
4. The implementation method of the antenna based on characteristic mode polarization reconfigurable antenna according to claim 1, characterized in that in the step 40:
when the midpoint A feeds the antenna, the antenna realizes resonance at a specific frequency, and the current distribution of the resonance is the same-phase superposition result of the first characteristic mode and the second characteristic mode, so that the linear polarization radiation characteristic is realized.
5. The implementation method of the antenna based on characteristic mode polarization reconfigurable antenna according to claim 1, characterized in that in the step 50:
and tuning the phase of the second characteristic mode, and when the phase of the second characteristic mode is ninety degrees different from the phase of the first characteristic mode, feeding to realize the same-frequency circularly polarized radiation characteristic.
6. The implementation method of the antenna based on characteristic mode polarization reconfigurable antenna according to claim 1, characterized in that in the step 20:
in the first characteristic mode, current flows out from the corner point C of the rectangular metal ring structure, passes through the other two corner points and finally flows into the corner point B.
7. The implementation method of the antenna based on characteristic mode polarization reconfigurable method of claim 1, wherein in the step 20:
in the second characteristic mode, the corner points B and C of the rectangular metal ring structure are points through which current flows halfway.
8. The implementation method of the antenna based on the characteristic mode polarization reconfigurable antenna, according to claim 1, wherein the rectangular metal ring structure is square.
9. The implementation method of the antenna based on the characteristic mode polarization reconfigurable technology of claim 1, wherein the side length of the rectangular metal ring structure is 200mm, and 8pF capacitor or 40Nh inductor is loaded at the corner points B and C.
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Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN206301949U (en) * | 2016-12-29 | 2017-07-04 | 深圳天珑无线科技有限公司 | Directional diagram reconstructable aerial and communication apparatus |
| CN108172999A (en) * | 2017-12-27 | 2018-06-15 | 西安电子科技大学 | The design method of the 2 port mimo antenna of directional diagram reconstructable of the feature based theory of modules |
| CN108429001A (en) * | 2018-03-08 | 2018-08-21 | 电子科技大学 | A kind of multipolarization reconfigurable antenna |
| CN110880645A (en) * | 2019-10-09 | 2020-03-13 | 重庆大学 | Polarization reconfigurable method based on super-surface antenna |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP4027967B2 (en) * | 2006-04-14 | 2007-12-26 | 松下電器産業株式会社 | Polarization switching / directivity variable antenna |
| DE102009011542A1 (en) * | 2009-03-03 | 2010-09-09 | Heinz Prof. Dr.-Ing. Lindenmeier | Antenna for receiving circularly in a direction of rotation of the polarization of broadcast satellite radio signals |
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Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN206301949U (en) * | 2016-12-29 | 2017-07-04 | 深圳天珑无线科技有限公司 | Directional diagram reconstructable aerial and communication apparatus |
| CN108172999A (en) * | 2017-12-27 | 2018-06-15 | 西安电子科技大学 | The design method of the 2 port mimo antenna of directional diagram reconstructable of the feature based theory of modules |
| CN108429001A (en) * | 2018-03-08 | 2018-08-21 | 电子科技大学 | A kind of multipolarization reconfigurable antenna |
| CN110880645A (en) * | 2019-10-09 | 2020-03-13 | 重庆大学 | Polarization reconfigurable method based on super-surface antenna |
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Address after: 215300 Room 009, No. 55, Shengchuang Road, Yushan Town, Kunshan, Suzhou, Jiangsu Province Patentee after: KUNSHAN RUIXIANG XUNTONG COMMUNICATION TECHNOLOGY Co.,Ltd. Country or region after: China Address before: 215300 no.1689-5 Zizhu Road, Yushan Town, Kunshan City, Suzhou City, Jiangsu Province Patentee before: KUNSHAN RUIXIANG XUNTONG COMMUNICATION TECHNOLOGY Co.,Ltd. Country or region before: China |