CN107221739B - RFID reader antenna based on orthogonal slot technology - Google Patents
RFID reader antenna based on orthogonal slot technology Download PDFInfo
- Publication number
- CN107221739B CN107221739B CN201710439409.7A CN201710439409A CN107221739B CN 107221739 B CN107221739 B CN 107221739B CN 201710439409 A CN201710439409 A CN 201710439409A CN 107221739 B CN107221739 B CN 107221739B
- Authority
- CN
- China
- Prior art keywords
- slot
- dielectric substrate
- gap
- orthogonal
- reader antenna
- 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.)
- Active
Links
Images
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01Q—ANTENNAS, i.e. RADIO AERIALS
- H01Q1/00—Details of, or arrangements associated with, antennas
- H01Q1/12—Supports; Mounting means
- H01Q1/22—Supports; Mounting means by structural association with other equipment or articles
- H01Q1/2208—Supports; Mounting means by structural association with other equipment or articles associated with components used in interrogation type services, i.e. in systems for information exchange between an interrogator/reader and a tag/transponder, e.g. in Radio Frequency Identification [RFID] systems
- H01Q1/2225—Supports; Mounting means by structural association with other equipment or articles associated with components used in interrogation type services, i.e. in systems for information exchange between an interrogator/reader and a tag/transponder, e.g. in Radio Frequency Identification [RFID] systems used in active tags, i.e. provided with its own power source or in passive tags, i.e. deriving power from RF signal
-
- 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
- H01Q1/38—Structural form of radiating elements, e.g. cone, spiral, umbrella; Particular materials used therewith formed by a conductive layer on an insulating support
-
- 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
Landscapes
- Waveguide Aerials (AREA)
Abstract
The invention discloses an RFID reader antenna based on an orthogonal slot technology, which comprises a dielectric substrate, wherein a Z-shaped feeder line is printed on the back surface of the dielectric substrate, a first slot, a second slot, a third slot, a fourth slot and a fifth slot are printed on the front surface of the dielectric substrate, the first slot, the second slot and the fifth slot are symmetrical relative to the diagonal line of the dielectric substrate, and the third slot and the fourth slot are symmetrical relative to the diagonal line of the dielectric substrate; the three PIN diodes are respectively arranged at the initial section, the middle section and the end section of the second gap, and the working states of the three PIN diodes are the same. The circularly polarized reader antenna disclosed by the invention covers a universal UHF frequency band and a WLAN frequency band, and has the excellent characteristics of small size, wide bandwidth, insensitivity to polarization and reconfigurable working frequency band.
Description
Technical Field
The invention relates to a reconfigurable dual-frequency circularly polarized antenna, in particular to an RFID reader antenna based on an orthogonal slot technology.
Background
In recent years, the development of RFID technology has been accelerated, and the RFID technology is gradually applied to warehouse management, retail systems, and the like. UHF (ultra high frequency 0.9 GHz) and WLAN (wireless metropolitan area network 2.45 GHz) frequency band RFID (radio frequency identification) systems have the advantages of long detection distance, high reading speed, high data transmission rate and the like, so that the RFID systems have the advantages in many practical applications. UHF frequency bands allocated by various countries are not uniform, so that the antenna needs to cover a universal UHF frequency band of 0.84-0.96 GHz. A typical RFID system consists of a reader antenna and a tag antenna, wherein the tag antenna is usually linearly polarized. Since the polarization of the tag antenna is random, the reader antenna is required to have a circular polarization characteristic so as to avoid a serious polarization mismatch between the reader antenna and the tag antenna.
The challenge in designing RFID circular polarization reader antennas today is to cover both the general UHF band (0.84-0.96 GHz) and the WLAN band (2.4-2.48 GHz) while maintaining a small size. The following are common circular polarization techniques: for the corner cut of the radiation patch, a perturbation unit, a cross dipole antenna, a feed network with 90-degree phase difference and the like are introduced into the square slot. However, these methods have disadvantages of large size and narrow bandwidth. The slot antenna has the advantages of simple structure, low profile, easy impedance matching, wide bandwidth and high radiation efficiency. Therefore, the circularly polarized antenna can be designed by using the slot, and the size can be kept small while the broadband is achieved.
Disclosure of Invention
In order to overcome the defects and shortcomings in the prior art, the invention provides the RFID reader antenna based on the orthogonal slot technology, and the reader antenna has the advantages of wide frequency band, small size, easiness in manufacturing, reconfigurable working frequency band and the like.
The invention adopts the following technical scheme:
an RFID reader antenna based on an orthogonal slot technology comprises a dielectric substrate, wherein a Z-shaped feeder line is printed on the back surface of the dielectric substrate, a first slot, a second slot, a third slot, a fourth slot and a fifth slot are printed on the front surface of the dielectric substrate, the first slot, the second slot and the fifth slot are symmetrical relative to a diagonal of the dielectric substrate, and the third slot and the fourth slot are symmetrical relative to the diagonal of the dielectric substrate;
the three PIN diodes are respectively arranged at the initial section, the middle section and the end section of the second gap, and the working states of the three PIN diodes are the same.
The first gap is formed by two L-shaped branches, the long sides of the two L-shaped branches are connected in an orthogonal mode and are symmetrical about the diagonal of the medium substrate, and openings are formed in the short sides of the two L-shaped branches.
The second slit is formed by two orthogonal L-shaped branches, and the second slit is positioned in an area surrounded by the two L-shaped branches of the first slit.
The third and fourth slits are both rectangular.
The fifth slot is formed by two mutually orthogonal rectangular branches.
And the PIN diode positioned in the middle section of the second slot is specifically arranged at the position of the front surface of the dielectric substrate corresponding to the top end branch in the Z-shaped feeder line.
The invention has the beneficial effects that:
(1) Compared with the existing antenna design applying the RFID circularly polarized reader, the bending, opening and orthogonal gaps provided by the invention can effectively reduce the size of the antenna;
(2) In the invention, the circular polarization bandwidth is effectively increased by etching the slots which are symmetrical about the diagonal line of the antenna, so that the universal UHF frequency band (0.84-0.96 GHz) and the WLAN frequency band (2.4-2.48 GHz) can be covered;
(3) The two working frequency bands can be independently adjusted, and cannot influence each other;
(4) The working frequency band can be switched by controlling the states of the 3 PIN diodes.
Drawings
FIG. 1 is a schematic structural view of the present invention;
FIG. 2 is a dimensional schematic of an embodiment of the invention;
FIG. 3 is a return loss plot of a simulation of an embodiment of the antenna of FIG. 1 after installation;
fig. 4 is an axial ratio diagram of a simulation of the implementation example of fig. 1 after the antenna is installed.
Detailed Description
The present invention will be described in further detail with reference to examples and drawings, but the embodiments of the present invention are not limited thereto.
Examples
As shown in fig. 1 and fig. 2, an RFID reader antenna based on orthogonal slot technology includes a dielectric substrate, the back of the dielectric substrate is printed with a Z-shaped feeder 6, the front of the dielectric substrate 8 is printed with a first, a second, a third, a fourth and a fifth slots 1, 2, 3, 4, 5, the first slot 1, the second slot 2 and the fifth slot 5 are symmetrical with respect to the diagonal of the dielectric substrate, the third slot 3 and the fourth slot 4 are symmetrical with respect to the diagonal of the dielectric substrate, the diagonal of the dielectric substrate is the same, the diagonal of the dielectric substrate in this embodiment is the diagonal of the dielectric substrate which is obtuse angle with the positive direction of the horizontal plane, and the circular polarization bandwidth of the antenna is effectively increased.
The three PIN diodes are arranged at the initial section 7a, the middle section 7b and the final section 7c of the second gap respectively, are in the same working state, are closed or simultaneously open, and correspond to working modes of a UHF frequency band and a WLAN frequency band respectively, so that the reconstruction of the working frequency band is realized.
The third gap 4 and the fourth gap 3 are both rectangular, the two gaps are symmetrical with respect to the diagonal line of the medium substrate, the third gap is arranged in the horizontal direction and is connected with the left side edge of the medium substrate, and the fourth gap is arranged in the vertical direction and is connected with the upper side edge of the medium substrate.
The fifth gap is formed by two mutually orthogonal rectangular branches, and the fifth gap is positioned at the tail part of a diagonal line of the medium substrate.
The Z-shaped feed line 6 is composed of three sequentially vertical branches, and a PIN diode is arranged at a position where the front surface of the dielectric substrate corresponding to the top branch of the Z-shaped feed line coincides with the middle section of the second slot, so that a broadband circularly polarized bandwidth and an impedance bandwidth are generated.
The technical scheme of the invention is realized as follows:
firstly, the circular polarization characteristic covering the general UHF frequency band is realized. The front surface of the dielectric substrate is printed with a first slot which is opened, bent and orthogonal to form a main body of UHF frequency band circular polarization radiation, the back surface of the dielectric substrate is printed with a Z-shaped feeder line, the feeder line passes through the vicinity of the center of the first slot, and the current on two orthogonal arms of the first slot forms a phase difference of 90 degrees, so that circular polarization is realized. And then, printing a third gap, a fourth gap and a fifth gap which are symmetrical and orthogonal with respect to the diagonal line of the antenna on the front surface of the dielectric substrate, so that the circularly polarized bandwidth covers the universal UHF frequency band.
Secondly, the circularly polarized characteristic of the WLAN frequency band is realized, a second gap with an opening, a bend and an orthogonal is printed to form a main body of the circularly polarized radiation of the WLAN frequency band, and the Z-shaped feeder passes through the vicinity of the center of the second gap, so that the circularly polarized characteristic of the WLAN frequency band is realized.
And finally, realizing the reconfiguration of the working frequency band. And the three PIN diodes on the front surface of the dielectric substrate are respectively positioned at two ends of the second gap and above the microstrip line, and the three PIN diodes are in a closed state or an open state at the same time and respectively correspond to working modes of a UHF frequency band and a WLAN frequency band, so that the reconstruction of the working frequency band is realized.
In order to verify the effectiveness of the present solution, specific examples are given below for explanation.
In this example, an FR4 dielectric substrate having a relative dielectric constant of 4.4, a loss tangent of 0.02 and a thickness of 0.8mm was selected, and the planar dimensions of the dielectric substrate were L × L, where L =98mm. The distance from the apex of the first slit to the left of the substrate is L1=59mm, the length of the third and fourth slits is L2=43.5mm, and the length of one side of the fifth slit is L3=42mm. The first slit has a maximum width W1=11mm, and the second, third and fourth slits have widths W2=5mm, W3=8mm, and W4=10mm, respectively. In practical implementation, a coaxial line of 50 ohms is used for direct feeding, the inner conductor of the coaxial line is connected with the microstrip feed line, and the outer conductor is connected with the radiation patch.
The simulated return loss and axial ratio results for the RFID reader antenna fabricated with the dimensions shown in fig. 2 above are shown in fig. 3 and 4, respectively. As can be seen from the figure, the RFID reader antenna has the return loss of less than-10 dB and the axial ratio of less than 3dB within 0.75-1.1GHz and 2.36-2.7GHz, and covers the common UHF frequency band (0.84-0.96 GHz) and the WLAN frequency band (2.4-2.48 GHz).
The above embodiments are preferred embodiments of the present invention, but the present invention is not limited to the above embodiments, and any other changes, modifications, substitutions, combinations, and simplifications which do not depart from the spirit and principle of the present invention should be construed as equivalents thereof, and all such changes, modifications, substitutions, combinations, and simplifications are intended to be included in the scope of the present invention.
Claims (3)
1. An RFID reader antenna based on an orthogonal slot technology is characterized by comprising a dielectric substrate, wherein a Z-shaped feeder line is printed on the back surface of the dielectric substrate, a first slot, a second slot, a third slot, a fourth slot and a fifth slot are printed on the front surface of the dielectric substrate, the first slot, the second slot and the fifth slot are symmetrical about a diagonal of the dielectric substrate, and the third slot and the fourth slot are symmetrical about the diagonal of the dielectric substrate;
the three PIN diodes are respectively arranged at the initial section, the middle section and the end section of the second gap, and the working states of the three PIN diodes are the same;
the first gap is formed by two L-shaped branches, long sides of the two L-shaped branches are connected in an orthogonal mode and are symmetrical about the diagonal line of the medium substrate, and openings are formed in the short sides of the two L-shaped branches;
the second gap is formed by two orthogonal L-shaped branches and is positioned in an area surrounded by the two L-shaped branches of the first gap;
the PIN diode is positioned in the middle section of the second gap and arranged on the position, corresponding to the front surface of the dielectric substrate, of the top end branch in the Z-shaped feeder line;
the Z-shaped feed line passes near the center of the first slot and current formation 90 occurs on the two orthogonal arms of the first slot 0 Phase difference, thereby realizing circular polarization.
2. The RFID reader antenna of claim 1, wherein the third and fourth slots are each rectangular.
3. The RFID reader antenna of claim 1, wherein the fifth slot is formed by two mutually orthogonal rectangular branches.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN201710439409.7A CN107221739B (en) | 2017-06-12 | 2017-06-12 | RFID reader antenna based on orthogonal slot technology |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN201710439409.7A CN107221739B (en) | 2017-06-12 | 2017-06-12 | RFID reader antenna based on orthogonal slot technology |
Publications (2)
Publication Number | Publication Date |
---|---|
CN107221739A CN107221739A (en) | 2017-09-29 |
CN107221739B true CN107221739B (en) | 2023-02-14 |
Family
ID=59948730
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
CN201710439409.7A Active CN107221739B (en) | 2017-06-12 | 2017-06-12 | RFID reader antenna based on orthogonal slot technology |
Country Status (1)
Country | Link |
---|---|
CN (1) | CN107221739B (en) |
Families Citing this family (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN113131182B (en) * | 2019-12-30 | 2023-06-20 | 华为技术有限公司 | Antenna and electronic equipment |
Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB8804708D0 (en) * | 1988-02-29 | 1990-11-21 | Stc Plc | Crossed slot antenna |
EP0831547A2 (en) * | 1996-09-20 | 1998-03-25 | Murata Manufacturing Co., Ltd. | Microstrip antenna |
WO2008113171A1 (en) * | 2007-03-19 | 2008-09-25 | Research In Motion Limited | Multi-band slot-strip antenna |
FR2943185A1 (en) * | 2009-03-13 | 2010-09-17 | Thales Sa | Reconfigurable polarization patch antenna, has rectangular slits coupling microstrip patch with printed line to polarize patch according to directions, which are associated with rectangular slits |
CN102544722A (en) * | 2012-01-04 | 2012-07-04 | 电子科技大学 | Polarization reconfigurable high-gain panel antenna |
CN102832450A (en) * | 2012-07-02 | 2012-12-19 | 上海大学 | Novel dual-frequency and polarization reconfigurable antenna |
Family Cites Families (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US7812783B2 (en) * | 2006-12-18 | 2010-10-12 | Hong Kong Applied Science And Technology Research Institute Co., Ltd. | Miniaturized orthogonal antenna system |
JP2013232833A (en) * | 2012-05-01 | 2013-11-14 | Fujitsu Ltd | Antenna device |
TWI563804B (en) * | 2015-01-21 | 2016-12-21 | Wistron Neweb Corp | Microstrip antenna transceiver |
-
2017
- 2017-06-12 CN CN201710439409.7A patent/CN107221739B/en active Active
Patent Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB8804708D0 (en) * | 1988-02-29 | 1990-11-21 | Stc Plc | Crossed slot antenna |
EP0831547A2 (en) * | 1996-09-20 | 1998-03-25 | Murata Manufacturing Co., Ltd. | Microstrip antenna |
WO2008113171A1 (en) * | 2007-03-19 | 2008-09-25 | Research In Motion Limited | Multi-band slot-strip antenna |
FR2943185A1 (en) * | 2009-03-13 | 2010-09-17 | Thales Sa | Reconfigurable polarization patch antenna, has rectangular slits coupling microstrip patch with printed line to polarize patch according to directions, which are associated with rectangular slits |
CN102544722A (en) * | 2012-01-04 | 2012-07-04 | 电子科技大学 | Polarization reconfigurable high-gain panel antenna |
CN102832450A (en) * | 2012-07-02 | 2012-12-19 | 上海大学 | Novel dual-frequency and polarization reconfigurable antenna |
Also Published As
Publication number | Publication date |
---|---|
CN107221739A (en) | 2017-09-29 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
KR100848237B1 (en) | Wireless tag and antenna for wireless tag | |
CN106207444B (en) | Dual-polarized high-gain and broadband complementary antenna | |
CN111864368B (en) | Low-profile broadband circularly polarized antenna for 5G communication and design method thereof | |
CN102610908A (en) | Ultra wide band four-tape circularly polarized antenna | |
CN111653869B (en) | Patch loaded broadband dual-polarized base station antenna | |
EP1193796A1 (en) | Dipole feed arrangement for corner reflector antenna | |
CN104701628A (en) | Broadband circularly polarized micostrip antenna | |
CN110783704A (en) | Dual-via-hole probe feed integrated substrate gap waveguide circularly polarized antenna | |
Kumar et al. | Design of multi‐polarised quad‐band planar antenna with parasitic multistubs for multiband wireless communication | |
US8106832B2 (en) | Circularly polarized patch antenna with single supply point | |
US20120261478A1 (en) | Rfid tag | |
Midya et al. | Triple‐band dual‐sense circularly polarised planar monopole antenna | |
CN116864975A (en) | SIW-based broadband millimeter wave plane circularly polarized magnetic dipole antenna | |
CN110718742A (en) | Miniaturized high-gain RFID reader-writer antenna | |
Kannadhasan et al. | Performance improvement of slot antenna using various parameters and band pass filter | |
CN112909529B (en) | Two-dimensional multi-beam super-surface antenna capable of realizing wide-band and wide-angle scanning | |
CN107221739B (en) | RFID reader antenna based on orthogonal slot technology | |
CN108808253B (en) | Back cavity type slot antenna of substrate integrated waveguide based on loading short-circuit nails | |
KR101064418B1 (en) | Circularly polarized tag antenna having ground surface | |
CN207038706U (en) | A kind of Broadband circularly polarized antenna based on V-type gap | |
KR20100002558A (en) | Dual-band antenna using slots | |
CN108808254B (en) | Back cavity type slot antenna of substrate integrated waveguide based on loading short-circuit nails | |
CN113383464B (en) | Dual-frequency dual-polarized antenna and electronic equipment | |
CN107221746A (en) | A kind of Broadband circularly polarized antenna based on V-type gap | |
CN112054289B (en) | Electronic device |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
PB01 | Publication | ||
PB01 | Publication | ||
SE01 | Entry into force of request for substantive examination | ||
SE01 | Entry into force of request for substantive examination | ||
GR01 | Patent grant | ||
GR01 | Patent grant |