CN102437421A - Anti-metal tag antenna applied in RFID (radio frequency identification device) system on UHF (ultra high frequency) band - Google Patents
Anti-metal tag antenna applied in RFID (radio frequency identification device) system on UHF (ultra high frequency) band Download PDFInfo
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- CN102437421A CN102437421A CN 201110264191 CN201110264191A CN102437421A CN 102437421 A CN102437421 A CN 102437421A CN 201110264191 CN201110264191 CN 201110264191 CN 201110264191 A CN201110264191 A CN 201110264191A CN 102437421 A CN102437421 A CN 102437421A
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Abstract
The invention relates to an anti-metal tag antenna applied in an RFID (radio frequency identification device) system on a UHF (ultra high frequency) band, relating to the technical field of a radio frequency identification type electronic tag. The antenna mainly comprises a metal substrate, a dielectric plate and an antenna structure. The antenna structure is arranged on the upper surface of the dielectric plate, the metal substrate is arranged on the lower surface of the dielectric plate, and the antenna structure is communicated with the metal substrate through metal through holes. The antenna structure mainly comprises an asymmetric metal radiating surface and an open circuit line, and the open circuit line is connected with the radiating surface and is arranged parallel to feeder lines. The feeder lines on the two sides of a chip are respectively connected with the metal radiating surface and the metal through holes. Since the radiating surface of the antenna is asymmetric, current paths are different, the dual-band approximation of the antenna to the same resonant point can be achieved, and the bandwidth of the antenna can be broadened. High gain and broad bandwidth can be achieved simultaneously, and the theoretical reading distance is more than 16m in the American frequency band from 902MHz and 928MHz. The anti-metal antenna can be applied in situations with large reading distances, such as license plate identification.
Description
Technical field
The present invention relates to a kind of radio frequency recognizing electronic label, it is characterized in that working in hyper band, be applied on the car plate.
Background technology
Radio frequency identification (Radio Frequency Identification, be called for short RFID) is a kind ofly to carry out contactless bidirectional data communication through wireless radio frequency mode, thus the technology that target is discerned.Radio-frequency recognition system generally is made up of reader (Reader) and electronic tag (Tag).Electronic tag is made up of on-chip antenna and chip, carries out exchanges data through electromagnetic wave and reader, has intelligent read and encrypted communication function.Antenna is a vital device in the rfid system, and rfid system is realized emission, received electromagnetic wave through radio-frequency antenna, thereby realizes the identification of reader to electronic tag.
Radio-frequency recognition system operates mainly in low frequency, high frequency, hyperfrequency and microwave frequency band.Low frequency and high-frequency radio frequency system accomplish identification through the mode of inductance coupling high, and it is near to read distance.And hyperfrequency and microwave radio system accomplish identification through the mode of electromagnetic wave transmission, and it is far away to read distance.At present, the frequency of utilization of international standard recommendation hyperfrequency (Ultra High Frequency is called for short UHF) band RFID equipment is 860MHz～960MHz.Wherein, the frequency range that use the North America is 902MHz～928MHz, and the frequency range that use in Europe is 865MHz～868MHz.China's Ministry of Information Industry has issued uhf band rfid system application specifies in April, 2007, China adopts 840MHz～845MHz and 920MHz～925MHz to use frequency range as the uhf band rfid system, and the power of wireless transmitting device is defined as 2W ERP.Electronic tag is divided into active label and passive label, and the self-contained battery of active label is that itself and reader communication provide energy, and passive label then receives the electromagnetic wave that sends from reader through label antenna and obtains energy activated chip.
The radio frequency of hyper band is very responsive to metal, when the hyperfrequency label is placed on the metal surface, and the reading distance and can reduce rapidly of label, even can not read.This is because the such boundary condition of metal has changed radiation efficiency, impedance matching and the directional diagram of label antenna.And in the super high frequency radio frequency of quite a few application, need label be affixed on the metal surface, like vehicle, container and can or the like.Because plane antenna structure forming label cost is low, be more suitable for large-scale production, so the anti-metal tag antenna of studying plane structure has real value very much.And the recognition distance of the at present existing planar structure label antenna that can be applicable to the metal background is generally in 10m, and it is very low that existing antenna or bandwidth gain well, or the gain high bandwidth is very narrow.How overcoming this problem is research emphasis of the present invention.
Summary of the invention
In order to overcome the deficiency of prior art, the concrete application that the present invention is directed to car plate proposes the hyperfrequency anti-metal tag antenna of a kind of broadband, high-gain.This anti-metal antenna has broadband, high gain characteristics, and it can place high 3mm, plane sizes is the metallic cavity of 90mm*65mm.This antenna can form the resonance double frequency, and-three dB bandwidth is 900MHz～944MHz, and the gain at the 915MHz place reaches 4.77dBi.Adopt suitable read write line, the theory recognition distance of the anti-metal antenna of the present invention in U.S. 902MHz～928MHz frequency range is greater than 16 meters.
The technical solution adopted for the present invention to solve the technical problems is a anti-metal tag antenna that is applied to the uhf band rfid system of design, and it comprises metal base plate, dielectric-slab, metallic vias and antenna structure.Antenna structure is at the dielectric-slab upper surface, and metal base plate is at the lower surface of dielectric-slab, and antenna structure is communicated with through metallic vias and metal base plate.Wherein, antenna structure comprises asymmetric metal radiating surface, first feeder line, second feeder line, connects radiating surface and is parallel to two sections open-circuit lines of feeder line.The first feeder line right side is connected label chip with second feeder line left side, and first feeder line passes on left hole knockout and realizes short circuit, and the second feeder line right side connects asymmetric radiating surface.The radiating surface of antenna is asymmetric, makes current path different, thereby makes the double frequency of antenna approach same resonance point, has enlarged the beamwidth of antenna.Near two sections open-circuit lines through the adding feeder line have increased current path, are of value to the expansion of antenna radiation pattern.
Compared with prior art, the present invention has following advantage and beneficial effect:
(1) a anti-metal tag antenna that is applied to the uhf band rfid system of the present invention is with the asymmetric mode of radiating surface, makes current path different, makes the double frequency of antenna approach near the same resonance point through adjusting, enlarged the beamwidth of antenna.
(2) a anti-metal tag antenna that is applied to the uhf band rfid system of the present invention connects plane antenna structure and metal ground plate through metallic vias, has increased antenna gain.
(3) a anti-metal tag antenna that is applied to the uhf band rfid system of the present invention is applied in the metallic cavity, has characteristics such as volume is little, simple in structure.
(4) a theory of anti-metal tag antenna in the 900MHz-940MHz scope that is applied to the uhf band rfid system of the present invention reads distance greater than 16m, in the vehicle identification system that can be applicable to run at high speed.
Description of drawings
Below in conjunction with accompanying drawing and embodiment the present invention is further specified.
Fig. 1 is a uhf band rfid system anti-metal tag antenna structural representation that is applied to;
Fig. 2 is a uhf band rfid system anti-metal tag antenna vertical view that is applied to;
Fig. 3 is a uhf band rfid system anti-metal tag antenna end view that is applied to;
Fig. 4 is a impedance plot that is applied to uhf band rfid system anti-metal tag antenna, and solid line is represented resistance among the figure, and dotted line is represented reactance;
Fig. 5 is a reflection coefficient chart that is applied to uhf band rfid system anti-metal tag antenna;
Fig. 6 is that a gain that is applied to uhf band rfid system anti-metal tag antenna is with frequency variation curve figure;
Fig. 7 is that a theory that is applied to uhf band rfid system anti-metal tag antenna reads distance with frequency variation curve figure;
Among the figure, 1 is radiating surface, and 2,3 is open-circuit line in the groove, and 4 is second feeder line, and 5 is first feeder line, and 6 is metallic vias, and 7 is label chip, and 8 is metal base plate, and 9 is antenna stack, and 10 is dielectric-slab.
Embodiment
This programme is for covering U.S.'s super high frequency radio frequency identification frequency, being applied to distinguish the anti-metal tag antenna of distance greater than the car plate identification occasion of 16m.Label antenna of the present invention is realized the design of hyperfrequency anti-metal tag antenna through adopting closed stub, and label chip adopts NXP G2 model ultrahigh-frequency radio-frequency tag, and the impedance of chip when 915MHz is (16-j*148) Ohm.Be directed against anti-metal tag antenna of the present invention below and combine accompanying drawing to be elaborated.
A uhf band rfid system anti-metal tag antenna that is applied to of the present invention, antenna structure comprises: 1, radiating surface 2, open-circuit line 3, open-circuit line 4, second feeder line 5, first feeder line 6, metallic vias 7, label chip.Form groove between radiating surface 1 and feeder line 4 and 5, regulate the insert depth of groove and resonance frequency and the matching degree that width can change antenna.There is metallic vias 6 on the right side of first feeder line, passes dielectric-slab 10 and is communicated with metal base plate 8.The radiating surface of antenna is asymmetric about feeder line 4 and 5, makes current path different, through size adjustment, can DFS double frequency shift to same resonance point with antenna near, thereby enlarge the beamwidth of antenna.And in the groove with two sections open-circuit lines on feeder line plane, increased current path, benefit the expansion of antenna radiation pattern.
A uhf band rfid system anti-metal tag antenna that is applied to of the present invention, medium substrate adopts polytetrafluoroethylmaterial material, and relative dielectric constant is 3.38, and loss angle tangent is 0.002, and dielectric-slab thickness is 3.04mm.1, radiating surface 2, open-circuit line 3, open-circuit line 4, second feeder line 5, first feeder line 7, label chip belong to the upper surface of medium substrate 10, and metal base plate 8 belongs to the lower surface of medium substrate 10.Upper and lower surface is communicated with through metallic vias 6.
For super high frequency radio frequency identification label, its chip impedance generally is a plural number.In order to realize the ceiling capacity transmission between antenna and the chip, need the input impedance and the chip impedance conjugate impedance match of antenna, promptly real part is equal, imaginary part is opposite.This also just requires the real part and the imaginary part of the input impedance of label antenna that certain regulating power is all arranged.For this anti-metal tag antenna, it belongs to the microband paste structure, the one section closed stub of having connected.Can know by radio circuit knowledge,, can change the position of short dot, thereby regulate reactive component through regulating the length of second feeder line 5.And the insert depth of groove and width all have considerable influence to the impedance of this antenna, so can realize the coupling of antenna and chip through regulating above structure.
A total length that is applied to the radiating surface 1 of uhf band rfid system anti-metal tag antenna of the present invention is 86mm, and width is 57mm.Groove insert depth in the radiating surface is 30mm, and width is 14mm.The length of first feeder line is 4.6mm, and width is 3mm.The length of second feeder line is 22.4mm, and width is 3mm.Open- circuit line 3 and 4 length are 19mm, and width is 1mm.The radiating surface of this anti-metal tag antenna has adopted asymmetric structure, is beneficial to the bandwidth expansion like this.Through the HFSS Electromagnetic Simulation, the impedance curve of antenna, reflection coefficient curve are respectively like Figure 4 and 5.As can be seen from the figure, antenna has formed the resonance double frequency near 915MHz, from impedance operator, mainly is because near the fluctuation up and down this frequency of reactance curve.This anti-metal antenna-three dB bandwidth is 900MHz～944MHz, meets the requirement of U.S. RFID frequency range.The gain of antenna can find out that with change curve such as Fig. 6 of frequency at U.S. frequency range 902MHz～928MHz, gain is more than 4.5dBi.
A uhf band rfid system anti-metal tag antenna that is applied to of the present invention is placed in the car plate, and height all around is 3mm, can think to be operated in the metallic cavity of 3mm insert depth.The reading and writing device antenna that adopts GSIT company to produce, its antenna gain is the 12dBi horizontal polarization, inserts antenna power 0.5W.Consider that this anti-metal antenna polarization mode also is linear polarization, so, just can reduce the energy loss of bringing by polarization as long as the position of placing is reasonable.Fig. 7 has provided when not considering polarization loss, and the theory of this anti-metal antenna reads distance.Can find out that in U.S. 902MHz～928MHz frequency range, the recognition of this antenna distance is greater than 16 meters.
Such scheme is a kind of embodiment of the present invention, multiple different application scheme can be arranged under characteristic according to the invention, but these application schemes needs only characteristic according to the invention, all should belong to rights protection scope of the present invention.
Claims (6)
1. a anti-metal tag antenna that is applied to the uhf band rfid system is characterized in that comprising upper strata antenna structure, middle level dielectric-slab and lower metal base plate, and the antenna on upper strata is communicated with the base plate of lower floor through metallic vias (6).The antenna structure on upper strata comprises asymmetric metal radiating surface (1), first feeder line (5), second feeder line (4), connect radiating surface and be parallel to two sections open-circuit lines (2) and (3) of feeder line.Look from feed, the radiating surface of this antenna is asymmetric, makes that like this current path of antenna is asymmetric, thereby has increased the radiation mode of antenna.Form groove in the middle of the asymmetric radiating surface (1), regulate the insert depth and the width of groove and can regulate antenna resonant frequency and matching degree.First feeder line (5) and the middle label chip (7), the other end short circuit of first feeder line (5) of being connected of second feeder line (6).
2. a anti-metal tag antenna that is applied to the uhf band rfid system according to claim 1 is characterized in that, this antenna first feeder line (5) is communicated with through metallic vias and metal base plate, has formed closed stub.
3. a anti-metal tag antenna that is applied to the uhf band rfid system according to claim 1; It is characterized in that radiating surface (1) is asymmetric about feed, through regulating the shape and the size of radiating surface; The resonance double frequency is transferred near the same resonance frequency, enlarge the bandwidth of antenna.
4. a anti-metal tag antenna that is applied to the uhf band rfid system according to claim 1 is characterized in that, forms groove in the middle of the asymmetric radiating surface (1), in groove, increases by two open-circuit lines, has increased coupling, has improved match condition.
5. a anti-metal tag antenna that is applied to the uhf band rfid system according to claim 1 is characterized in that, can adjust the thickness of dielectric-slab according to practical situations, and antenna and application object is integrated.
6. a anti-metal tag antenna that is applied to the uhf band rfid system according to claim 1 is characterized in that, the visual concrete applicable cases in the position of feed and adjusting.
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| Application Number | Priority Date | Filing Date | Title |
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| CN 201110264191 CN102437421A (en) | 2011-09-07 | 2011-09-07 | Anti-metal tag antenna applied in RFID (radio frequency identification device) system on UHF (ultra high frequency) band |
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| Application Number | Priority Date | Filing Date | Title |
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| CN 201110264191 CN102437421A (en) | 2011-09-07 | 2011-09-07 | Anti-metal tag antenna applied in RFID (radio frequency identification device) system on UHF (ultra high frequency) band |
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| CN102437421A true CN102437421A (en) | 2012-05-02 |
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Cited By (18)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104600424A (en) * | 2015-01-06 | 2015-05-06 | 西安电子科技大学 | Circularly polarized anti-metal tag antenna |
| CN105226383A (en) * | 2015-10-08 | 2016-01-06 | 徐利 | A kind of low section ultrahigh frequency RFID anti-metal tag antenna |
| RU173877U1 (en) * | 2016-12-05 | 2017-09-15 | Олег Николаевич Гашников | RFID REGISTRATION LABEL |
| CN107545298A (en) * | 2017-08-11 | 2018-01-05 | 电子科技大学 | A kind of flexible anti-metal tag |
| CN107634333A (en) * | 2017-09-22 | 2018-01-26 | 北京邮电大学 | A UHF radio frequency identification anti-metal circular polarisation label antenna |
| CN107658559A (en) * | 2017-10-20 | 2018-02-02 | 杭州泽济电子科技有限公司 | Miniaturization anti-metal antenna and label |
| CN107946759A (en) * | 2017-11-15 | 2018-04-20 | 北京工业大学 | A kind of array strain transducer based on microstrip antenna formula RFID tag |
| RU2654081C1 (en) * | 2016-12-05 | 2018-05-16 | Олег Николаевич Гашников | Rfid tag of registration mark |
| CN108345932A (en) * | 2018-05-21 | 2018-07-31 | 宜兴启明星物联技术有限公司 | Double frequency anti-metal tag |
| CN108593713A (en) * | 2018-04-20 | 2018-09-28 | 武汉理工大学 | Passive and wireless paster antenna sensor based on RFID technique and wireless measurement method |
| CN108899647A (en) * | 2018-07-04 | 2018-11-27 | 北京宏诚创新科技有限公司 | Novel passive ultrahigh-frequency tag antenna applied to printing |
| CN109159506A (en) * | 2018-07-27 | 2019-01-08 | 中国人民解放军陆军装甲兵学院 | A kind of flexibility UHF RFID anti-metal tag |
| CN111211399A (en) * | 2020-03-04 | 2020-05-29 | 电子科技大学 | Metal-resistant ultrahigh frequency electronic tag antenna conformal to petroleum pipe sleeve wall |
| CN111446543A (en) * | 2020-02-16 | 2020-07-24 | 西安电子科技大学 | Single-feed dual-circular polarization directional antenna with extremely-low frequency ratio and antenna system |
| CN111639737A (en) * | 2019-09-27 | 2020-09-08 | 深圳锐驰物联科技有限公司 | Novel ultrahigh frequency anti-metal label production method |
| CN112292784A (en) * | 2018-07-02 | 2021-01-29 | 斯道拉恩索公司 | Metal container comprising UHF RFID tag |
| CN112563737A (en) * | 2020-11-02 | 2021-03-26 | 中山大学 | Dual-frequency antenna comprising periodic leaky-wave structure and manufacturing method thereof |
| TWI741523B (en) * | 2020-03-06 | 2021-10-01 | 遠創智慧股份有限公司 | Electronic tag |
-
2011
- 2011-09-07 CN CN 201110264191 patent/CN102437421A/en active Pending
Cited By (21)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104600424A (en) * | 2015-01-06 | 2015-05-06 | 西安电子科技大学 | Circularly polarized anti-metal tag antenna |
| CN105226383A (en) * | 2015-10-08 | 2016-01-06 | 徐利 | A kind of low section ultrahigh frequency RFID anti-metal tag antenna |
| RU173877U1 (en) * | 2016-12-05 | 2017-09-15 | Олег Николаевич Гашников | RFID REGISTRATION LABEL |
| RU2654081C1 (en) * | 2016-12-05 | 2018-05-16 | Олег Николаевич Гашников | Rfid tag of registration mark |
| CN107545298A (en) * | 2017-08-11 | 2018-01-05 | 电子科技大学 | A kind of flexible anti-metal tag |
| CN107545298B (en) * | 2017-08-11 | 2019-11-26 | 电子科技大学 | A kind of flexibility anti-metal tag |
| CN107634333A (en) * | 2017-09-22 | 2018-01-26 | 北京邮电大学 | A UHF radio frequency identification anti-metal circular polarisation label antenna |
| CN107658559A (en) * | 2017-10-20 | 2018-02-02 | 杭州泽济电子科技有限公司 | Miniaturization anti-metal antenna and label |
| CN107658559B (en) * | 2017-10-20 | 2024-03-08 | 杭州泽济电子科技有限公司 | Miniaturized anti-metal antenna and tag |
| CN107946759A (en) * | 2017-11-15 | 2018-04-20 | 北京工业大学 | A kind of array strain transducer based on microstrip antenna formula RFID tag |
| CN108593713A (en) * | 2018-04-20 | 2018-09-28 | 武汉理工大学 | Passive and wireless paster antenna sensor based on RFID technique and wireless measurement method |
| CN108345932A (en) * | 2018-05-21 | 2018-07-31 | 宜兴启明星物联技术有限公司 | Double frequency anti-metal tag |
| CN112292784A (en) * | 2018-07-02 | 2021-01-29 | 斯道拉恩索公司 | Metal container comprising UHF RFID tag |
| CN108899647A (en) * | 2018-07-04 | 2018-11-27 | 北京宏诚创新科技有限公司 | Novel passive ultrahigh-frequency tag antenna applied to printing |
| CN109159506B (en) * | 2018-07-27 | 2020-11-24 | 中国人民解放军陆军装甲兵学院 | Flexible UHF RFID anti-metal label |
| CN109159506A (en) * | 2018-07-27 | 2019-01-08 | 中国人民解放军陆军装甲兵学院 | A kind of flexibility UHF RFID anti-metal tag |
| CN111639737A (en) * | 2019-09-27 | 2020-09-08 | 深圳锐驰物联科技有限公司 | Novel ultrahigh frequency anti-metal label production method |
| CN111446543A (en) * | 2020-02-16 | 2020-07-24 | 西安电子科技大学 | Single-feed dual-circular polarization directional antenna with extremely-low frequency ratio and antenna system |
| CN111211399A (en) * | 2020-03-04 | 2020-05-29 | 电子科技大学 | Metal-resistant ultrahigh frequency electronic tag antenna conformal to petroleum pipe sleeve wall |
| TWI741523B (en) * | 2020-03-06 | 2021-10-01 | 遠創智慧股份有限公司 | Electronic tag |
| CN112563737A (en) * | 2020-11-02 | 2021-03-26 | 中山大学 | Dual-frequency antenna comprising periodic leaky-wave structure and manufacturing method thereof |
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Application publication date: 20120502 |