CN103474765B - A kind of circular polarization cross dipole antenna and preparation method thereof - Google Patents
A kind of circular polarization cross dipole antenna and preparation method thereof Download PDFInfo
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- CN103474765B CN103474765B CN201310420597.0A CN201310420597A CN103474765B CN 103474765 B CN103474765 B CN 103474765B CN 201310420597 A CN201310420597 A CN 201310420597A CN 103474765 B CN103474765 B CN 103474765B
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Abstract
The present invention discloses a kind of circular polarization cross dipole antenna and preparation method thereof, described antenna comprises metallic reflection plate, be positioned at the medium substrate above metallic reflection plate, be arranged on the crossed dipoles radiating element of medium substrate upper and lower surface, the coaxial feed unit be connected with crossed dipoles radiating element, described crossed dipoles radiating element comprises the upper dipole and lower dipole that are separately positioned on described medium substrate upper and lower surface, described coaxial feed unit comprises inner wire and outer conductor, described inner wire is through metallic reflection plate, medium substrate is connected with upper dipole, described outer conductor is connected with lower dipole through metallic reflection plate.Cross dipole antenna is incorporated on microband paste by the present invention, circular polarization cross dipole antenna of the present invention is made not only to have microstrip antenna volume little, lightweight and easily and application platform feature conformal, easy of integration, also there is very wide impedance bandwidth and circular polarization bandwidth, gain be high, the feature of low cost of manufacture.
Description
Technical field
The present invention relates to microwave antenna art field, particularly relate to a kind of circular polarization cross dipole antenna and preparation method thereof.
Background technology
The develop rapidly of wireless technology, antenna technology is driven also to obtain tremendous expansion, particularly circular polarized antenna every field is in wireless communications widely used, such as satellite communication, radio frequency identification (RFID), wireless lan (wlan), global positioning system (GPS), and the BEI-DOU position system of China's independent research, all use circular polarized antenna.Apply more extensive, higher to the requirement of antenna performance, all require that antenna impedance bandwidth sum circular polarization bandwidth (axial ratio bandwidth) is all very wide in many applications.The method of broadening circular polarized antenna bandwidth has a lot, such as additional resonance branch, loaded medium resonator, use multi-layer microstrip antenna, the power splitter adding broadband does feeding network etc., but these methods have its shortcoming, complex structure, otherwise size is very large, otherwise gain is very low.Such as, though multilayer micro-strip paster antenna can Bandwidth to a certain extent, but complex structure and manufacturing cost increase; The power splitter in additional resonator and loaded medium resonator and interpolation broadband does the complexity that feeding network both increases Antenna Design, is unfavorable for producing in enormous quantities.
Therefore, prior art has yet to be improved and developed.
Summary of the invention
In view of above-mentioned the deficiencies in the prior art, the object of the present invention is to provide a kind of circular polarization cross dipole antenna and preparation method thereof, be intended to the technical sophistication solving current broadening circular polarized antenna bandwidth, increase the problems such as cost, gain be low.
Technical scheme of the present invention is as follows:
A kind of circular polarization cross dipole antenna, wherein, described antenna comprises metallic reflection plate, be arranged on the medium substrate above described metallic reflection plate, be arranged on the crossed dipoles radiating element of described medium substrate upper and lower surface, the coaxial feed unit be connected with described crossed dipoles radiating element, described crossed dipoles radiating element comprises the upper dipole and lower dipole that are separately positioned on described medium substrate upper and lower surface, described coaxial feed unit comprises inner wire and outer conductor, described inner wire is connected with described upper dipole with medium substrate through described metallic reflection plate, described outer conductor is connected with described lower dipole through described metallic reflection plate.
Described circular polarization cross dipole antenna, wherein, described upper dipole and lower dipole are centrosymmetric and distribute.
Described circular polarization cross dipole antenna, wherein, described upper dipole is identical with size with the shape of lower dipole.
Described circular polarization cross dipole antenna, wherein, described upper dipole and lower dipole comprise two dipole arm respectively, are connected between described two dipole arm by annulus, wherein, have 90 degree of phase differences between described two dipole arm.
Described circular polarization cross dipole antenna, wherein, described dipole arm is the dipole arm of terminal open circuit.
Described circular polarization cross dipole antenna, wherein, described upper dipole is identical with the annular radii of lower dipole, and described annulus is for cutting the annulus of 1/4th girths.
Described circular polarization cross dipole antenna, wherein, all has 90 degree of phase differences between arbitrary neighborhood two dipole arm of four dipole arm of described upper and lower dipole.
Described circular polarization cross dipole antenna, wherein, described medium substrate and metallic reflection plate are be arranged in parallel up and down and are fixed together by fulcrum pin.
A preparation method for circular polarization cross dipole antenna as above, wherein, said method comprising the steps of:
A, prepare medium substrate, and in described medium substrate upper and lower surface, the identical upper dipole of shape size and lower dipole are set respectively according to Central Symmetry principle, wherein, described upper dipole is provided with two dipole arm be connected by annulus with lower dipole, regulates the radius of described annulus to make to have 90 degree of phase differences between dipole and two dipole arm of lower dipole respectively;
B, preparation metallic reflection plate, be arranged in parallel the medium substrate and metallic reflection plate that are provided with upper and lower dipole up and down and fixed by fulcrum pin;
C, on described metallic reflection plate and medium substrate, be drilled with coaxial aperture, inner wire and the outer conductor of described coaxial feed unit are set in described coaxial aperture, wherein, described inner wire is connected with described upper dipole, and described outer conductor is connected with described lower dipole.
A kind of electronic installation, have wireless transmission function, wherein, described electronic installation comprises the circular polarization cross dipole antenna prepared by method described above.
Beneficial effect: the invention provides a kind of circular polarization cross dipole antenna and preparation method thereof, cross dipole antenna is incorporated on microband paste by the present invention, circular polarization cross dipole antenna of the present invention is made not only to have microstrip antenna volume little, lightweight and easily and application platform feature conformal, easy of integration, also there is very wide impedance bandwidth and circular polarization bandwidth (axial ratio bandwidth), the feature that gain is high, manufacturing cost also reduces further simultaneously.
Accompanying drawing explanation
Fig. 1 is the structural representation of circular polarization cross dipole antenna of the present invention.
Fig. 2 is the cross section structure schematic diagram of circular polarization cross dipole antenna of the present invention.
Fig. 3 is the structure for amplifying schematic diagram that in Fig. 2, A refers to region.
Fig. 4 is circular polarization cross dipole antenna preparation method flow chart of the present invention.
Fig. 5 is the return loss emulation experiment datagram of circular polarization cross dipole antenna of the present invention.
Fig. 6 is the axial ratio emulation experiment datagram of circular polarization cross dipole antenna of the present invention.
Fig. 7 is the gain emulation experiment datagram of circular polarization cross dipole antenna of the present invention.
Fig. 8 is that circular polarization cross dipole antenna of the present invention is at 2.45GHz place Phi=0
oleft-right-hand circular polarization directional diagram.
Fig. 9 is that circular polarization cross dipole antenna of the present invention is at 2.45GHz place Phi=90
oleft-right-hand circular polarization directional diagram.
Embodiment
The invention provides a kind of circular polarization cross dipole antenna and preparation method thereof, for making object of the present invention, technical scheme and effect clearly, clearly, the present invention is described in more detail below.Should be appreciated that specific embodiment described herein only in order to explain the present invention, be not intended to limit the present invention.
As Fig. 1, Fig. 2, a kind of circular polarization cross dipole antenna shown in Fig. 3, this antenna applications is in ISM band radio communication, wherein, described antenna comprises metallic reflection plate 100, be arranged on the medium substrate 200 above described metallic reflection plate 100, be arranged on the crossed dipoles radiating element of described medium substrate 200 upper and lower surface, the coaxial feed unit 400 be connected with described crossed dipoles radiating element, described crossed dipoles radiating element comprises the upper dipole 310 of the similar microstrip antenna being printed on described medium substrate upper and lower surface respectively and lower dipole 320, described coaxial feed unit 400 comprises inner wire 410 and outer conductor 420, described inner wire 410 is connected with described upper dipole 310 with medium substrate through described metallic reflection plate, described outer conductor 420 is connected 320 through described metallic reflection plate with described lower dipole.
Described upper dipole is identical with size with the shape of lower dipole, described upper dipole and lower dipole are centrosymmetric and distribute, namely descend dipole to be equivalent to dipole around medium substrate central rotation 180 degree, then to moving down a dielectric substrate thickness, be namely printed on the lower surface of medium substrate.Described upper dipole and lower dipole comprise two dipole arm respectively, connected by annulus 330 between described two dipole arm, preferably, described upper dipole is identical with the annular radii of lower dipole, described annulus is for cutting the annulus of 1/4th girths, namely described annulus is the annulus with complete circle 3/4 girth, wherein, between described two dipole arm, there are 90 degree of phase differences, these 90 degree of phase differences are by regulating the radius of described annulus to realize to during certain value, when arranging the annulus of correct radial, namely make the girth of annulus equal or be approximately equal to four/radius for the moment of aerial radiation wavelength.Annulus just becomes the phase delay line of 90 °, thus make the phase difference between dipole two dipole arm with 90 degree, then circular polarization radiation is produced, in addition, regulate the width of described annulus, the impedance of antenna can be changed, when arranging the annulus of suitable width, can the impedance bandwidth of broadening antenna.Upper and lower dipole all makes to have 90 degree of phase differences and broadening impedance bandwidth between dipole arm by as above arranging.To be connected with coaxial outer conductor by lower dipole and upper dipole is connected with coaxial inner wire, make the electric current of upper and lower dipole contrary, there is between two dipole arm again in conjunction with upper and lower dipole the setting of 90 degree of phase differences, make, between arbitrary neighborhood two dipole arm in four dipole arm of described upper and lower dipole, all there are 90 degree of phase differences.Like this, with regard to whole antenna, further broadening circular polarization bandwidth, and, adopt the wide dipole arm of terminal open circuit also to contribute to regulating impedance bandwidth and circular polarization bandwidth.
Described medium substrate 200 is be arranged in parallel with metallic reflection plate about 100 and is fixed together by the fulcrum pin 500 that four angles are arranged.
The preparation method of circular polarization cross dipole antenna as shown in Figure 4, wherein, said method comprising the steps of:
S100, prepare medium substrate, and in described medium substrate upper and lower surface, the identical upper dipole of shape size and lower dipole are set respectively according to Central Symmetry principle, wherein, described upper dipole is provided with two dipole arm be connected by annulus with lower dipole, regulates the radius of described annulus to make to have 90 degree of phase differences between dipole and two dipole arm of lower dipole respectively;
S200, preparation metallic reflection plate, be arranged in parallel the medium substrate and metallic reflection plate that are provided with upper and lower dipole up and down and fixed by fulcrum pin;
S300, on described metallic reflection plate and medium substrate, be drilled with coaxial aperture, inner wire and the outer conductor of described coaxial feed unit are set in described coaxial aperture, wherein, described inner wire is connected with described upper dipole, and described outer conductor is connected with described lower dipole.
In actual fabrication process, by regulating the size of circular polarization cross dipole antenna each several part, make this antenna can be applied to each frequency range.
A kind of electronic installation, have wireless transmission function, wherein, described electronic installation comprises the circular polarization cross dipole antenna prepared by method described above, and described circular polarization cross dipole antenna sends for the reception of wireless signal.
As shown in figures 5-9, the centre frequency of described circular polarization cross dipole antenna work is 2.45GHz, and the lateral dimension of antenna is 55mm × 55mm, longitudinal direction is highly 29.6mm; Above-mentioned antenna is in frequency range 2.02GHz-3.19GHz, and return loss is less than-10dB, and impedance bandwidth is 47.7%.Antenna axial ratio is less than 3dB in 2.30GHz-3.15GHz, and circular polarization bandwidth (axial ratio bandwidth) reaches 34.7%; Antenna meets return loss simultaneously, and to be less than the frequency band range that-10dB and axial ratio be less than 3dB be 2.30GHz-3.15GHz.Antenna reaches maximum gain 7.05dBi at 2.35GHz place, and the average gain within the scope of 2.30GHz-3.15GHz is 6.4dBi.
The invention provides a kind of circular polarization cross dipole antenna and preparation method thereof, cross dipole antenna is incorporated on microband paste by the present invention, circular polarization cross dipole antenna of the present invention is made not only to have microstrip antenna volume little, lightweight and easily and application platform feature conformal, easy of integration, also there is very wide impedance bandwidth and circular polarization bandwidth (axial ratio bandwidth), the feature that gain is high, manufacturing cost also reduces further simultaneously.
In sum, these are only the embodiment selected by the present invention, be not intended to limit protection scope of the present invention.Within the spirit and principles in the present invention all, any amendment done, equivalent replacement, improvement etc., all should be included within protection scope of the present invention.
Claims (3)
1. a circular polarization cross dipole antenna, it is characterized in that, described antenna comprises metallic reflection plate, be arranged on the medium substrate above described metallic reflection plate, be arranged on the crossed dipoles radiating element of described medium substrate upper and lower surface, the coaxial feed unit be connected with described crossed dipoles radiating element, described crossed dipoles radiating element comprises the upper dipole and lower dipole that are separately positioned on described medium substrate upper and lower surface, described coaxial feed unit comprises inner wire and outer conductor, described inner wire is connected with described upper dipole with medium substrate through described metallic reflection plate, described outer conductor is connected with described lower dipole through described metallic reflection plate,
Described upper dipole is identical with the annular radii of lower dipole, and described annulus is for cutting the annulus of 1/4th girths;
Between arbitrary neighborhood two dipole arm of four dipole arm of described upper and lower dipole, all there are 90 degree of phase differences;
Described medium substrate and metallic reflection plate are be arranged in parallel up and down and are fixed together by fulcrum pin;
Described circular polarization cross dipole antenna is applied to ISM band radio communication;
Described upper dipole and lower dipole are centrosymmetric and distribute;
Described upper dipole is identical with size with the shape of lower dipole;
Described upper dipole and lower dipole comprise two dipole arm respectively, are connected between described two dipole arm by annulus, wherein, have 90 degree of phase differences between described two dipole arm;
Described dipole arm is the dipole arm of terminal open circuit.
2. a preparation method for circular polarization cross dipole antenna as claimed in claim 1, is characterized in that, said method comprising the steps of:
A, prepare medium substrate, and in described medium substrate upper and lower surface, the identical upper dipole of shape size and lower dipole are set respectively according to Central Symmetry principle, wherein, described upper dipole is provided with two dipole arm be connected by annulus with lower dipole, regulates the radius of described annulus to make to have 90 degree of phase differences between dipole and two dipole arm of lower dipole respectively;
B, preparation metallic reflection plate, be arranged in parallel the medium substrate and metallic reflection plate that are provided with upper and lower dipole up and down and fixed by fulcrum pin;
C, on described metallic reflection plate and medium substrate, be drilled with coaxial aperture, inner wire and the outer conductor of described coaxial feed unit are set in described coaxial aperture, wherein, described inner wire is connected with described upper dipole, and described outer conductor is connected with described lower dipole.
3. an electronic installation, has wireless transmission function, it is characterized in that, described electronic installation comprises the circular polarization cross dipole antenna using method as claimed in claim 2 to prepare.
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN106384883A (en) * | 2016-10-26 | 2017-02-08 | 复旦大学 | Meta-material cross dipole circularly-polarized antenna |
| CN107317099A (en) * | 2017-03-27 | 2017-11-03 | 广东顺德中山大学卡内基梅隆大学国际联合研究院 | A kind of multiband circular polarisation wideband cross dipole antenna |
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| CN107317099A (en) * | 2017-03-27 | 2017-11-03 | 广东顺德中山大学卡内基梅隆大学国际联合研究院 | A kind of multiband circular polarisation wideband cross dipole antenna |
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