CN101916907B - Ultrahigh frequency band near field RFID reader-writer antenna - Google Patents
Ultrahigh frequency band near field RFID reader-writer antenna Download PDFInfo
- Publication number
- CN101916907B CN101916907B CN201010221193.5A CN201010221193A CN101916907B CN 101916907 B CN101916907 B CN 101916907B CN 201010221193 A CN201010221193 A CN 201010221193A CN 101916907 B CN101916907 B CN 101916907B
- Authority
- CN
- China
- Prior art keywords
- pcb substrate
- antenna
- coplanar
- base plate
- frequency band
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
Images
Landscapes
- Waveguide Aerials (AREA)
Abstract
The invention discloses an ultrahigh frequency band near field RFID reader-writer antenna. A coaxial connector is connected with one end of a coplanar waveguide on a PCB base plate; the other end of the coplanar waveguide is connected to one end of a coplanar strip line by a balun; the other end of the coplanar strip line is connected with a resistor; the PCB base plate and a metal floor are supported by nylon columns on four corners of the PCB base plate; an air layer is formed between the PCB base plate and the metal floor; and a conduction band width, a gap width between conduction bands, the dielectric constant of the PCB base plate, the thickness of the air layer, the impedance of the balun and the parameters of a resistance value are subject to properly matching the impedance among the coplanar waveguide, the balun, the coplanar strip line and the resistor. The invention has relatively wide frequency band and relatively strong magnetic field, and the antennas with different lengths can be conveniently designed according to the application requirements under different circumstances.
Description
Technical field
The invention belongs to Antenna Construction Design technical field, relate to a kind of rfid interrogator antenna.
Background technology
RFID (Radio Frequency Identification, radio-frequency (RF) identification) technology is a kind of non-contacting automatic identification technology.Reading and writing device antenna plays key effect in rfid system.The frequency of reading and writing device antenna work may have low frequency (135kHz is following), high frequency (13.56MHz), hyperfrequency (860-960MHz) and microwave frequency band (more than 2.4GHz) etc.Reading and writing device antenna is divided according to operating distance, can be divided near field antenna and far field antenna.The near field reading and writing device antenna that works in hyperfrequency is highly suitable for work in narrow space.Because near field antenna is only closely locating just there is stronger electromagnetic field, the intensity of distance electromagnetic fields slightly far away sharply weakens, and the far gain of this antenna is very low, so antenna large-area metal around can't exert an influence to the performance of antenna.
Because ultrahigh frequency band near field RFID reader-writer antenna has a lot of premium properties, a lot of companies and individual have done many correlative studys, and have product to come out.Impinj company has proposed a lot of antennas based on coupling loop; Siemens company has proposed a kind of loop antenna of amounting to; The people such as Daniel M.Dobkin have proposed a kind of loop antenna by lumped capacitor compensation of phase; The common feature of these antenna is to take to make someway the electric current on ring to keep same-phase, and the magnetic field inducing is like this strongest, but above-mentioned these antenna all belongs to resonant antenna, and phase compensation amount is relevant with frequency, so bandwidth is generally narrow.
Summary of the invention
In order to overcome the narrower deficiency of prior art bandwidth, the invention provides a kind of ultrahigh frequency band near field RFID reader-writer antenna.This antenna is a kind of traveling-wave antenna, and frequency band is wider, and magnetic field is stronger.
The technical solution adopted for the present invention to solve the technical problems is: comprise coaxial fitting, PCB substrate, co-planar waveguide, Ba Lun and coplanar striplines, one end of coaxial fitting and co-planar waveguide on PCB substrate is connected, the other end of co-planar waveguide is connected on one end of coplanar striplines by Ba Lun, the other end of coplanar striplines is connected to resistance, between PCB substrate and metal floor, by the nylon column being positioned on four angles of PCB substrate, support, between PCB substrate and metal floor, form an air layer.The parameter of the gap width between selection conduction band width, conduction band, dielectric constant, air layer thickness, Ba Lun impedance and the resistance value of PCB substrate, makes impedance matching between co-planar waveguide, Ba Lun, coplanar striplines and resistance.On metal floor, have reverse image current, air layer is thicker, and reverse image current is far away, and near field is stronger.But air layer is thicker, the size of antenna is larger.
The invention has the beneficial effects as follows: antenna of the present invention is a kind of traveling-wave structure, and frequency band is wider; Between PCB substrate and metal floor, there is an air layer, both reduced the requirement to PCB substrate dielectric constant precision, weakened again the impact of metal floor retrodirective mirror image current, so magnetic field is stronger; This antenna is a kind of traveling-wave structure, and the length that changes antenna is little to performance change, so can, according to the needs of different applications, design easily the antenna of different length.
Below in conjunction with drawings and Examples, the present invention is further described.
Accompanying drawing explanation
Fig. 1 is ultrahigh frequency band near field RFID reader-writer antenna structural representation of the present invention.
Fig. 2 is the top view of Fig. 1.
Fig. 3 is the A-A cutaway view of Fig. 1.
In figure, 1, coaxial fitting, 2, co-planar waveguide, 3, Ba Lun, 4, coplanar striplines, 5, PCB substrate, 6, resistance, 7, air layer, 8, metal floor, 9, nylon column.
Embodiment
With reference to Fig. 1～3, the present invention is comprised of coaxial fitting 1, co-planar waveguide 2, Ba Lun 3, coplanar striplines 4, PCB substrate 5, resistance 6, air layer 7, metal floor 8 and nylon column 9.
Co-planar waveguide 2 and coplanar striplines 4 adopt the technology modes such as etching to be arranged on the upper surface of PCB substrate 5.The side that coaxial fitting 1 is close to PCB substrate 5 is welded on co-planar waveguide 2.Ba Lun 3 is welded between co-planar waveguide 2 and coplanar striplines 4.Resistance 6 is welded on the opposite side top of coplanar striplines 4.Between PCB substrate 5 and metal floor 8, by the nylon column 9 on four angles, support, in centre, form an air layer 7.
Embodiment mono-
The length of PCB substrate 5 and metal floor 8 and the size of width are 110mm and 50mm respectively; It is the FR4 dielectric-slab that 1.5mm, relative dielectric constant are 4.4 that PCB substrate 5 adopts thickness; The thickness of air layer 7 is 5mm.
Central guiding bandwidth and the gap width of selecting co-planar waveguide 2, making its characteristic impedance is 50 Ω, so that and coaxial fitting 1 coupling.Adopt the Ba Lun of 1: 4 impedance ratio.Ba Lun 3 is 50 Ω in the port Impedance of co-planar waveguide 2 one sides, in the port Impedance of coplanar striplines 4 one sides, is 200 Ω.The conduction band width of selecting coplanar striplines 4 is that the distance between 5mm and conduction band is 10mm, and making its characteristic impedance is 200 Ω.The impedance of resistance 6 is 200 Ω, and the characteristic impedance of coplanar striplines 4 coupling.
From coaxial fitting 1, through co-planar waveguide 2, Ba Lun 3, coplanar striplines 4, until resistance 6, impedance is all mated.Therefore be a kind of traveling-wave structure, frequency band is wider.
Opposite current on two conduction bands of coplanar striplines 4.On two conduction bands, the electric current of opposite direction can form the magnetic field perpendicular to PCB substrate 5 in the same way between two conduction bands.
Because this antenna is a traveling-wave antenna, coplanar striplines 4 is uniform transmission line, so can be according to the needs of different applications, change the length of coplanar striplines 4, other parameter constant, designs the antenna of different length, easily to obtain the different antenna zones of action.
Embodiment bis-
The increase of the reduction of coplanar striplines 4 characteristic impedances and air layer 7 thickness all can increase magnetic field intensity, further expands the operating distance of antenna.
The length of PCB substrate 5 and metal floor 8 and the size of width are 110mm and 80mm respectively; It is the FR4 dielectric-slab that 1.5mm, relative dielectric constant are 4.4 that PCB substrate 5 adopts thickness; The thickness of air layer 7 is 10mm.
Central guiding bandwidth and the gap width of selecting co-planar waveguide 2, making its characteristic impedance is 50 Ω, so that and coaxial fitting 1 coupling.Adopt the Ba Lun of 1: 2 impedance ratio.Ba Lun 3 is 50 Ω in the port Impedance of co-planar waveguide 2 one sides, in the port Impedance of coplanar striplines 4 one sides, is 100 Ω.The conduction band width of selecting coplanar striplines 4 is that the distance between 35mm and conduction band is 10mm, and making its characteristic impedance is 100 Ω.The impedance of resistance 6 is 100 Ω, and the characteristic impedance of coplanar striplines 4 coupling.From coaxial fitting 1, through co-planar waveguide 2, Ba Lun 3, coplanar striplines 4, until resistance 6, impedance is all mated.
Compare with embodiment mono-, in the present embodiment, the impedance of Ba Lun 3, coplanar striplines 4 and resistance 6 is all reduced to 100 Ω from 200 Ω.Because impedance reduces, the electric current on coplanar striplines 4 increases, so magnetic field strengthens.Compare with embodiment mono-, in the present embodiment, the thickness of air layer 7 is increased to 10mm from 5mm, on metal floor 8, the distance of retrodirective mirror image current has increased 10mm, so magnetic field strengthens.This antenna is the in the situation that of input power 1W, and operating distance is 5cm.Compare some increase of the antenna size of the present embodiment with embodiment mono-.In this embodiment, the operation principle of antenna is identical with embodiment mono-, repeats no more here.
Claims (1)
1. a ultrahigh frequency band near field RFID reader-writer antenna, comprise coaxial fitting, PCB substrate, co-planar waveguide, Ba Lun and coplanar striplines, it is characterized in that: one end of coaxial fitting and co-planar waveguide on PCB substrate is connected, the other end of co-planar waveguide is connected on one end of coplanar striplines by Ba Lun, the other end of coplanar striplines is connected to resistance, between PCB substrate and metal floor, by the nylon column being positioned on four angles of PCB substrate, support, between PCB substrate and metal floor, form an air layer; The parameter of the dielectric constant of the gap width between the width of co-planar waveguide and coplanar striplines, co-planar waveguide and coplanar striplines, PCB substrate, air layer thickness, Ba Lun impedance and resistance value so that between co-planar waveguide, Ba Lun, coplanar striplines and resistance impedance matching be as the criterion.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201010221193.5A CN101916907B (en) | 2010-07-08 | 2010-07-08 | Ultrahigh frequency band near field RFID reader-writer antenna |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201010221193.5A CN101916907B (en) | 2010-07-08 | 2010-07-08 | Ultrahigh frequency band near field RFID reader-writer antenna |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN101916907A CN101916907A (en) | 2010-12-15 |
| CN101916907B true CN101916907B (en) | 2014-04-02 |
Family
ID=43324341
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201010221193.5A Expired - Fee Related CN101916907B (en) | 2010-07-08 | 2010-07-08 | Ultrahigh frequency band near field RFID reader-writer antenna |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN101916907B (en) |
Families Citing this family (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102567775B (en) * | 2010-12-24 | 2016-06-08 | 上海曜传信息科技有限公司 | The UHF_RFID label of a kind of multimedium structure and antenna |
| CN102299413A (en) * | 2011-06-02 | 2011-12-28 | 西北工业大学 | UHF (ultra high frequency) RFID (radio frequency identification) reader-writer antenna of smart shelf |
| CN102820536B (en) * | 2012-08-22 | 2015-11-04 | 北京中欧美经济技术发展中心 | The radio frequency discrimination RFID reading and writing device antenna of hyperfrequency UHF |
| CN103050778B (en) * | 2013-01-18 | 2014-09-17 | 北京邮电大学 | Radio frequency identification near-field antenna integrated with plane impedance matching balun |
| CN103746173B (en) * | 2013-12-27 | 2016-06-08 | 青岛中科软件股份有限公司 | Plate carries the 485MHz radio-frequency module of PCB antenna |
| CN105891611B (en) * | 2016-04-08 | 2018-03-02 | 北京航空航天大学 | A kind of wide band miniature near field electrical field test probe |
| CN105717466B (en) * | 2016-04-08 | 2018-03-02 | 北京航空航天大学 | A kind of wide band miniature near field measurement of magnetic field probe |
| US10511097B2 (en) * | 2017-05-12 | 2019-12-17 | Energous Corporation | Near-field antennas for accumulating energy at a near-field distance with minimal far-field gain |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN201758174U (en) * | 2010-07-08 | 2011-03-09 | 西北工业大学 | Ultra-high frequency range near field FRID reader-writer antenna |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6046704A (en) * | 1999-01-06 | 2000-04-04 | Marconi Aerospace Systems Inc. Advanced Systems Division | Stamp-and-bend double-tuned radiating elements and antennas |
| WO2007097282A1 (en) * | 2006-02-23 | 2007-08-30 | Murata Manufacturing Co., Ltd. | Antenna device, array antenna, multisector antenna, and high frequency transceiver |
| GB2448551B (en) * | 2007-04-20 | 2010-03-31 | Iti Scotland Ltd | Ultra wideband antenna |
| TWI497821B (en) * | 2008-10-22 | 2015-08-21 | Sibeam Inc | A planar antenna |
-
2010
- 2010-07-08 CN CN201010221193.5A patent/CN101916907B/en not_active Expired - Fee Related
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN201758174U (en) * | 2010-07-08 | 2011-03-09 | 西北工业大学 | Ultra-high frequency range near field FRID reader-writer antenna |
Also Published As
| Publication number | Publication date |
|---|---|
| CN101916907A (en) | 2010-12-15 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN101916907B (en) | Ultrahigh frequency band near field RFID reader-writer antenna | |
| US8678295B2 (en) | Miniaturized radio-frequency identification tag and microstrip patch antenna thereof | |
| US10205232B2 (en) | Multi-antenna and radio apparatus including thereof | |
| CN205029009U (en) | Two wireless radio frequency identification antennas of circular polarization in broadband | |
| EP2797165A1 (en) | Rfid tag aerial with ultra-thin dual-frequency microstrip patch aerial array | |
| CN202205889U (en) | Microwave frequency band RFID (Radio Frequency Identification Device) tag antenna applied to nonmetal surface | |
| CN102110872A (en) | Radio frequency identification tag antenna applicable to non-metallic surface | |
| CN104733846A (en) | Small UHF meander-line dipole anti-metallic RFID label antenna | |
| WO2011034205A1 (en) | High frequency coupler | |
| WO2016127595A1 (en) | Radio frequency identification (rfid) tag antenna | |
| CN104241824A (en) | Combined type general reader antenna | |
| CN103715499B (en) | Annular UHF near-field RFID reader-writer antenna | |
| CN110718742A (en) | Miniaturized high-gain RFID reader-writer antenna | |
| CN201758174U (en) | Ultra-high frequency range near field FRID reader-writer antenna | |
| CN109149092B (en) | Compact single-feed broadband circularly polarized RFID reader antenna | |
| US8632009B2 (en) | Near field magnetic coupling antenna and RFID reader having the same | |
| CN109599671A (en) | A kind of coplanar wave guide feedback Dual-band circular polarization antenna | |
| CN112701449A (en) | Ultrahigh frequency high-gain double dipole tag antenna with low profile | |
| CN110247179B (en) | UHF near field RFID reader antenna capable of identifying randomly placed tags | |
| JP2007527174A (en) | Antenna structure for RFID tag | |
| CN108923111B (en) | UHF RFID near field reader antenna applied to liquid environment | |
| CN101867093B (en) | Ultrahigh frequency broadband quasi circular polarization micro-strip patch antenna | |
| CN108847522B (en) | Compact RFID antenna | |
| CN208336508U (en) | A kind of double open circuit parallel resonance short-range communication antennas | |
| US5818307A (en) | Directional coupler having inductor crossing microstrip transmission line |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20140402 Termination date: 20150708 |
|
| EXPY | Termination of patent right or utility model |