CN108875436A - A kind of R-T unit and card reader - Google Patents
A kind of R-T unit and card reader Download PDFInfo
- Publication number
- CN108875436A CN108875436A CN201810358461.4A CN201810358461A CN108875436A CN 108875436 A CN108875436 A CN 108875436A CN 201810358461 A CN201810358461 A CN 201810358461A CN 108875436 A CN108875436 A CN 108875436A
- Authority
- CN
- China
- Prior art keywords
- circuit
- connect
- unit
- node
- parallel
- 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.)
- Granted
Links
- 230000005540 biological transmission Effects 0.000 claims abstract description 48
- 239000003990 capacitor Substances 0.000 claims description 47
- 238000001514 detection method Methods 0.000 claims description 6
- 230000005611 electricity Effects 0.000 claims description 6
- 238000004891 communication Methods 0.000 abstract description 13
- 230000035945 sensitivity Effects 0.000 abstract description 8
- 230000008878 coupling Effects 0.000 description 8
- 238000010168 coupling process Methods 0.000 description 8
- 238000005859 coupling reaction Methods 0.000 description 8
- 230000008901 benefit Effects 0.000 description 7
- 238000010586 diagram Methods 0.000 description 6
- 238000000034 method Methods 0.000 description 6
- 230000001965 increasing effect Effects 0.000 description 5
- 230000004048 modification Effects 0.000 description 4
- 238000012986 modification Methods 0.000 description 4
- 230000000694 effects Effects 0.000 description 3
- 238000005516 engineering process Methods 0.000 description 2
- 238000001914 filtration Methods 0.000 description 2
- 230000001939 inductive effect Effects 0.000 description 2
- 229910044991 metal oxide Inorganic materials 0.000 description 2
- 150000004706 metal oxides Chemical class 0.000 description 2
- 230000008859 change Effects 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 239000004020 conductor Substances 0.000 description 1
- 230000005674 electromagnetic induction Effects 0.000 description 1
- 230000008569 process Effects 0.000 description 1
- 239000004065 semiconductor Substances 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 230000001052 transient effect Effects 0.000 description 1
Classifications
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06K—GRAPHICAL DATA READING; PRESENTATION OF DATA; RECORD CARRIERS; HANDLING RECORD CARRIERS
- G06K7/00—Methods or arrangements for sensing record carriers, e.g. for reading patterns
- G06K7/10—Methods or arrangements for sensing record carriers, e.g. for reading patterns by electromagnetic radiation, e.g. optical sensing; by corpuscular radiation
- G06K7/10009—Methods or arrangements for sensing record carriers, e.g. for reading patterns by electromagnetic radiation, e.g. optical sensing; by corpuscular radiation sensing by radiation using wavelengths larger than 0.1 mm, e.g. radio-waves or microwaves
- G06K7/10158—Methods or arrangements for sensing record carriers, e.g. for reading patterns by electromagnetic radiation, e.g. optical sensing; by corpuscular radiation sensing by radiation using wavelengths larger than 0.1 mm, e.g. radio-waves or microwaves methods and means used by the interrogation device for reliably powering the wireless record carriers using an electromagnetic interrogation field
- G06K7/10168—Methods or arrangements for sensing record carriers, e.g. for reading patterns by electromagnetic radiation, e.g. optical sensing; by corpuscular radiation sensing by radiation using wavelengths larger than 0.1 mm, e.g. radio-waves or microwaves methods and means used by the interrogation device for reliably powering the wireless record carriers using an electromagnetic interrogation field the powering being adversely affected by environmental influences, e.g. unwanted energy loss in the interrogation signal due to metallic or capacitive objects in the proximity of the interrogation device or in the proximity of the interrogated record carrier
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B5/00—Near-field transmission systems, e.g. inductive or capacitive transmission systems
- H04B5/40—Near-field transmission systems, e.g. inductive or capacitive transmission systems characterised by components specially adapted for near-field transmission
- H04B5/48—Transceivers
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B5/00—Near-field transmission systems, e.g. inductive or capacitive transmission systems
- H04B5/70—Near-field transmission systems, e.g. inductive or capacitive transmission systems specially adapted for specific purposes
- H04B5/77—Near-field transmission systems, e.g. inductive or capacitive transmission systems specially adapted for specific purposes for interrogation
Landscapes
- Engineering & Computer Science (AREA)
- Computer Networks & Wireless Communication (AREA)
- Physics & Mathematics (AREA)
- Signal Processing (AREA)
- Electromagnetism (AREA)
- Health & Medical Sciences (AREA)
- Toxicology (AREA)
- General Health & Medical Sciences (AREA)
- Computer Vision & Pattern Recognition (AREA)
- General Physics & Mathematics (AREA)
- Theoretical Computer Science (AREA)
- Artificial Intelligence (AREA)
- Near-Field Transmission Systems (AREA)
Abstract
The present invention provides a kind of R-T unit and card reader.The R-T unit includes：Micro-control unit, transmission circuit, the first detecting circuit and the second detecting circuit, first detecting circuit is connect with the first node in the transmission circuit, second detecting circuit is connect with the second node in the transmission circuit, the output signal of the first node and the second node is differential signal, the parallel circuit of first detecting circuit and second detecting circuit is connect with the receiving interface of the micro-control unit, and the transmission circuit is connect with the differential transmission interface of the micro-control unit.The invention also discloses the card reader with above-mentioned R-T unit.The present invention can be effectively reduced R-T unit signal carrier in the prior art and interfere scene that is big and influencing R-T unit sensitivity, can effectively improve its communication distance.
Description
Technical field
The present invention relates to the communications fields, relate more specifically to a kind of R-T unit and the card reader with the R-T unit.
Background technique
Near-field communication is also known as wireless near field communication, is a kind of short-range high frequency wireless communication technology, and electronics is allowed to set
Contactless Point-to-Point Data Transmission, exchange data are carried out between standby, are by contact-free formula RF identification (Radio
Frequency Identification, RFID) it is evolved, basis is RFID and interconnection technique.Radio-frequency recognition system packet
Include RFID electronic label and RFID card reader.Radio frequency letter is realized by coupling element between RFID electronic label and RFID card reader
Number space it is (contactless) coupling.In coupling channel, according to sequential relationship, the transmitting of energy and the exchange of data are realized.
RFID card reader is carried out wireless communication by antenna and RFID electronic label, may be implemented to tag recognition code and internal storage data
Read or write operation.
The basic functional principle of RFID is：After RFID electronic label enters magnetic field, the radio frequency that RFID card reader issues is received
Signal sends out the product information (Passive being stored in RFID electronic label chip by induced current energy obtained
Tag, passive label or passive tag), after RFID card reader reads information and decodes, send to Central Information System and carry out related number
According to processing.
Since RFID card reader needs to receive RFID while transmission power can provide enough energy to passive label
The faint reaction signal of electronic tag, the transmission power of RFID card reader and R-T unit sensitivity require it is relatively high, especially
Be require big card reading apart from when, RFID card reader card reading distance, transmission power and R-T unit sensitivity
It can not be linearly to improve, it is required that exponential other raising.
Between RFID card reader and RFID electronic label there are two types of the coupling types of radiofrequency signal：
(1) inductive coupling is realized by spatial high-frequency alternating magnetic field and is coupled according to the law of electromagnetic induction；
(2) electromagnetic backscatter couples, and according to the spatial rule of electromagnetic wave, the electromagnetic wave launched encounters mesh
Back reflection is marked, while carrying back target information.
In the prior art, when the radiofrequency signal between RFID card reader and RFID electronic label is inductive coupling, exist
The larger problem of interference of the carrier signal that transmitter itself issues to R-T unit itself.
Summary of the invention
The present invention is proposed, in view of the above problems in order to provide a kind of R-T unit at least being partially solved the above problem
And the card reader with the R-T unit.
According to one aspect of the invention, it provides a kind of R-T units, wherein including：Micro-control unit, transmission circuit,
First detecting circuit and the second detecting circuit,
First detecting circuit is connect with the first node in the transmission circuit, second detecting circuit with it is described
The output signal of second node connection in transmission circuit, the first node and the second node is differential signal, described
The parallel circuit of first detecting circuit and second detecting circuit is connect with the receiving interface of the micro-control unit,
The transmission circuit is connect with the differential transmission interface of the micro-control unit.
Illustratively, first detecting circuit includes the first coupled capacitor being connected in series, the first filter circuit and the
One one-way conduction circuit, second detecting circuit include the second coupled capacitor being connected in series, the second filter circuit and second
One-way conduction circuit.
Illustratively, the first end of first one-way conduction circuit is unidirectionally led to second end forward conduction, described second
The first end of circuit passband connects to second end forward conduction, the first end of first one-way conduction circuit and the first node
It connects, the first end of second one-way conduction circuit is connect with the second node.
Illustratively, first filter circuit includes the first parallel connection of the first filter capacitor and the first load resistance composition
Circuit, and/or, second filter circuit includes the second parallel circuit of the second filter capacitor and the second load resistance composition.
Illustratively, the first end of the first end of first coupled capacitor and second coupled capacitor and the reception
Interface connection,
First one-way conduction circuit include the first detector diode, first detector diode anode with it is described
First node connection, the cathode of first detector diode are connect with the first end of first parallel circuit, and described first
The first end of parallel circuit is also connect with the second end of first coupled capacitor, the second termination of first parallel circuit
Ground；And
Second one-way conduction circuit include the second detector diode, second detector diode anode with it is described
Second node connection, the cathode of second detector diode are connect with the first end of second parallel circuit, and described second
The first end of parallel circuit is also connect with the second end of second coupled capacitor, the second termination of second parallel circuit
Ground.
Illustratively, further include：
Input resistance, the first end of the input resistance are connect with the receiving interface, the second end of the input resistance
It is connect with the parallel connected end of first detecting circuit and second detecting circuit.
Illustratively, further include partially installing capacitor, the partially installing capacitor with it is inclined in the biasing circuit of the micro-control unit
Set resistor coupled in parallel.
Illustratively, the micro-control unit is provided with biasing interface, and the biasing resistor is arranged in the microcontroller list
First outside is simultaneously connected between the biasing interface and the receiving interface, and the biasing resistor is for biasing the microcontroller list
The input direct-current of member.
Illustratively, the transmission circuit includes Electro Magnetic Compatibility filter unit, match circuit and antenna.
Illustratively, the match circuit is balun/transformer matching circuitry.
According to one aspect of the invention, it provides a kind of card reader, the card reader includes above-mentioned R-T unit.
The present invention reduces R-T unit circuit by improving the signal quality of traditional detecting circuit using differential signal
Performance requirement.Near-field communication R-T unit signal carrier interference in the prior art, which can be effectively reduced, influences transmitting-receiving dress greatly
The scene of sensitivity is set, the communication distance of R-T unit can be effectively improved.
The above description is only an overview of the technical scheme of the present invention, in order to better understand the technical means of the present invention,
And it can be implemented in accordance with the contents of the specification, and in order to allow above and other objects of the present invention, feature and advantage can
It is clearer and more comprehensible, the followings are specific embodiments of the present invention.
Detailed description of the invention
The embodiment of the present invention is described in more detail in conjunction with the accompanying drawings, the above and other purposes of the present invention,
Feature and advantage will be apparent.Attached drawing is used to provide to further understand the embodiment of the present invention, and constitutes explanation
A part of book, is used to explain the present invention together with the embodiment of the present invention, is not construed as limiting the invention.In the accompanying drawings,
Identical reference label typically represents same parts or step.
Fig. 1 shows the block diagram of the R-T unit of one embodiment of the invention；
Fig. 2, Fig. 3 show two schematic circuits of the R-T unit of Fig. 1；
Fig. 4 shows the circuit diagram of the R-T unit of another embodiment of the present invention；
Fig. 5 shows the circuit diagram of the R-T unit of further embodiment of this invention；
Fig. 6 shows the circuit diagram of the R-T unit of yet another embodiment of the invention.
Specific embodiment
In order to enable the object, technical solutions and advantages of the present invention become apparent, root is described in detail below with reference to accompanying drawings
According to example embodiments of the present invention.Obviously, described embodiment is only a part of the embodiments of the present invention, rather than this hair
Bright whole embodiments, it should be appreciated that the present invention is not limited by example embodiment described herein.
In order to solve problem as described above, the embodiment of the present invention provides a kind of R-T unit and with the R-T unit
Card reader.
Existing R-T unit front end can realize mentioning for baseband envelope signal simply by diode detection circuit
It takes.Amplitude-modulated wave is passed through into detector diode.Due to the unilateal conduction characteristic of detector diode, the negative-going portion of amplitude-modulated signal is cut
It goes, only leaves its positive part.It is such as averaged (low-pass filtering) in each signal period of amplitude-modulated signal at this time, gained is to adjust
The wave packet (envelope) of width signal, as base band low frequency signal realize demodulation (detection) function.But there is hair in the prior art
Penetrate the larger problem of interference of the carrier signal to R-T unit itself of machine itself sending.The present invention one is shown referring to Fig. 1, Fig. 1
The block diagram of the R-T unit of a embodiment.R-T unit of the invention, including：Micro-control unit 1, transmission circuit 2, the first detection
Circuit 3 and the second detecting circuit 4.The micro-control unit 1 for example can be card reader chip, and micro-control unit 1 includes connecing
Mouthful RX and differential transmission interface TX includes first node V in transmission circuit 2EMC_pWith second node VEMC_n, wherein described first
First node V in detecting circuit 3 and the transmission circuit 2EMC_pConnection, second detecting circuit 4 and the transmission circuit 2
In second node VEMC_nConnection, the first node VEMC_pWith the second node VEMC_nOutput signal be differential signal,
The receiving interface RX of the parallel circuit of first detecting circuit 3 and second detecting circuit 4 and the micro-control unit 1 connects
It connects, the transmission circuit 2 is connect with the differential transmission interface TX of the micro-control unit 1.Wherein, the differential transmission interface TX packet
Include the first differential transmission interface TX1 and the second differential transmission interface TX2, first node VEMC_pIt is connect positioned at the first differential transmission
On the transmission circuit of mouth TX1 connection, second node VEMC_nOn the transmission circuit being connect with the first differential transmission interface TX2.
The R-T unit improves the signal quality of detecting circuit using differential signal, is conducive to the robustness of increase system entirety.And
And it can also be effectively reduced influence of the signal carrier interference to R-T unit sensitivity, and then effectively improve R-T unit
Communication distance.
Referring to fig. 2 and Fig. 3, Fig. 2, Fig. 3 show two schematic circuits of the R-T unit according to Fig. 1.The present embodiment
Micro-control unit can be realized by card reader chip.Card reader chip may include multiple interfaces.Wherein, RX is receiving interface,
TX1, TX2 are the first, second differential transmission interface respectively, and GND is ground terminal.TVSS is transient voltage pulses suppressor interface.
VTX1、VTX2、VEMC_P、VEMC_n、VANT_P、VANT_N、VEVP_P、VEVP_n、VCombNode respectively in circuit.Inductance LEMCAnd capacitor
CEMCCollectively constitute Electro Magnetic Compatibility filter unit 21.Capacitor CSERWith capacitor CPARCollectively constitute match circuit 22.Rightmost side dotted line
Capacitor, inductance and resistance in frame collectively constitute antenna 23.It can see the Electro Magnetic Compatibility filter unit of output by Fig. 2, Fig. 3
21 and match circuit 22 be symmetrical differential configuration, and receiving circuit is single-ended reception.
Referring to Fig. 3, in one embodiment, first detecting circuit 3 includes the first coupled capacitor being connected in series
CRX_p, the first filter circuit and the first one-way conduction circuit, second detecting circuit 4 includes the second coupling electricity being connected in series
Hold CRX_n, the second filter circuit and the second one-way conduction circuit.
In one embodiment, the first end of first one-way conduction circuit is to second end forward conduction, and described second
The first end of one-way conduction circuit is to second end forward conduction.The first end of first one-way conduction circuit and the first segment
Point VEMC_pConnection, the first end of second one-way conduction circuit and the second node VEMC_nConnection.Alternatively, first, second
One-way conduction circuit also can be reversed conducting, i.e., the first end of described first one-way conduction circuit to second end reverse-conducting, institute
The first end of the second one-way conduction circuit is stated to second end reverse-conducting.First, second one-way conduction circuit forward conduction is anti-
To conducting, substantial effect is had no to the realization of technical effect.
First one-way conduction circuit or the second one-way conduction circuit can be using diode, triode or metal oxides half
The device of the specific one-way conduction function such as conductor (Metal Oxide Semiconductor, MOS) pipe is realized, can also be used
The combinational circuit of multiple element composition with one-way conduction function is realized.One-way conduction electricity is described by taking diode as an example below
Road.
In one embodiment, the first filter circuit includes the first filter capacitor CFILT_pWith the first load resistance RFILT_pGroup
At the first parallel circuit, and/or, the second filter circuit include the second filter capacitor CFILT_nWith the second load resistance RFILT_nGroup
At the second parallel circuit.It should be understood that above are only an example of filter circuit, the filter circuit in the present embodiment can be with
For other circuits with filter function, for example, it is also possible to carry out equivalent variations to above-mentioned filter circuit to obtain other structures
Filter circuit.For example, the first load resistance RFILT_pSeries circuit, the series circuit are formed with a capacitor (not shown)
With the first filter capacitor CFILT_pThe parallel circuit of composition can also be used as the first filter circuit, can also similarly obtain second
Filter circuit, details are not described herein again.
In one embodiment, as shown in figure 3, the first coupled capacitor CRX_pFirst end, it is described second coupling electricity
Hold CRX_nFirst end connect with the receiving interface RX.First one-way conduction circuit includes the first detector diode Dp, the
When the first end and second end forward conduction of one one-way conduction circuit, the first detector diode DpAnode with described first
Node VEMC_pConnection, the first detector diode DpCathode connect with the first end of first parallel circuit, alternatively,
When the first end and second end reverse-conducting of one one-way conduction circuit, the first detector diode DpCathode and described first
Node VEMC_pConnection, the first detector diode DpAnode connect with the first end of first parallel circuit.Described
The first end of one parallel circuit also with the first coupled capacitor CRX_pSecond end connection, the second of first parallel circuit
End ground connection.All GND indicate ground terminal in attached drawing.Second one-way conduction circuit includes the second detector diode DN, the
When the first end and second end forward conduction of two one-way conduction circuits, the second detector diode DNAnode with described second
Node VEMC_nConnection, the second detector diode DNCathode connect with the first end of second parallel circuit, alternatively,
When the first end and second end reverse-conducting of two one-way conduction circuits, the second detector diode DNCathode and described second
Node VEMC_nConnection, the second detector diode DNAnode connect with the first end of second parallel circuit.Described
The first end of two parallel circuits also with the second coupled capacitor CRX_nSecond end connection, the second of second parallel circuit
End ground connection.Above-mentioned first detector diode DpWith the second detector diode DNIt is respectively used to realize the first one-way conduction circuit and the
The one-way conduction function of two one-way conduction circuits.Realize that one-way conduction function makes the realization of R-T unit simpler using diode
Single, cost is less expensive.
In another embodiment, R-T unit may also include input resistance RRX.First detecting circuit, 3 He in the R-T unit
Second detecting circuit 4 is via input resistance RRXIt is connect with receiving interface RX.The input resistance RRXFirst end and the reception
Interface RX connection.The input resistance RRXSecond end and first detecting circuit 3 and second detecting circuit 4 it is in parallel
End connection.Specifically, i.e. input resistance RRXSecond end and the first coupled capacitor CRX_pWith the second coupled capacitor CRX_nThe two
Parallel connected end connection.The first coupled capacitor C in Fig. 3RX_P, the second coupled capacitor CRX_NThe circuit formed with internal bias resistance,
It functions as a high-pass filter, for filtering out direct current caused by the first detecting circuit 3 and the second detecting circuit 4
Pressure.
Transmission circuit 2 can be the existing transmission circuit for card reader or the following transmitting-receiving for card reader occurred
Circuit not limits this in the present embodiment.For example, the transmission circuit 2 includes Electro Magnetic Compatibility filter unit 21, matching electricity
Road 22 and antenna 23.For example, Electro Magnetic Compatibility filter cell 21, match circuit 22 and antenna 23 are connected in series.First node
VEMC_pWith second node VEMC_nBetween Electro Magnetic Compatibility filter unit 21 and match circuit 22.
In one embodiment, the Electro Magnetic Compatibility filter unit 21 includes two filter capacitor CEMCIt is filtered with two
Inductance LEMC, two filter inductance LEMCOne end connect respectively with the first differential transmission interface TX1 and the second differential transmission interface TX2
It connects, two filter inductance LEMCThe respective other end respectively with two filter capacitor CEMCFirst end connection, two filter capacitors
CEMCSecond end ground connection.Each filter capacitor CEMCFirst end also connect with a first end of match circuit 22, matching electricity
Two second ends on road 22 and two ports of antenna connect.The first node VEMC_pIt is connect positioned at first differential transmission
The filter inductance L of mouth TX1 connectionEMCWith with filter inductance LEMCThe filter capacitor C of connectionEMCBetween, the second node VEMC_n
Positioned at the filter inductance L being connect with the second differential transmission interface TX2EMCWith with filter inductance LEMCThe filter capacitor of connection
CEMCBetween.
In addition, transmission circuit 2 can not also include Electro Magnetic Compatibility filter unit 21.For example, for the differential transmission of MCU
The case where what interface TX was issued is sine wave, differential transmission interface TX can directly be connect with match circuit 22.At this point, first segment
Point VEMC_pWith second node VEMC_nBetween differential transmission interface and match circuit 22.
The R-T unit improves the signal quality of detecting circuit using differential signal it can be seen from Fig. 2 and Fig. 3, drop
The low performance requirement to circuit.
Different with common detecting circuit to be, the present invention takes full advantage of the symmetry of match circuit and transmit circuit.
R-T unit port RX passes through CRX_pAnd CRX_nV is converged toCombEnd, the present invention provide difference to single-ended reception circuit in this way
The structure of high frequency carrier detecting circuit signal input, can bring the following benefits on the basis of increasing seldom device：Subtract
Small carrier wave ripple interference；The ripple frequency of detection is increased, it is made to be more easier to be filtered out by next stage baseband amplifier；And it mentions
The high sensitivity of R-T unit.
Referring to fig. 4, circuit diagram in accordance with another embodiment of the present invention is shown.In the present embodiment, other portions
The composition and connection relationship of parallel circuit are identical as embodiment illustrated in fig. 3, and difference is that the present embodiment further includes partially installing capacitor
Cbias, the partially installing capacitor CbiasWith the biasing resistor R in the biasing circuit of the micro-control unit 1biasIt is in parallel.Wherein, micro-control
The biasing circuit of unit 1 processed can be set in inside, can also realize in outside.The biasing resistor R of the present embodimentbiasSetting exists
Outside the micro-control unit 1, the micro-control unit 1 is provided with biasing interface Bias, the biasing resistor RbiasIt is connected to institute
State biasing interface BiasBetween the receiving interface RX.The biasing resistor RbiasFor biasing the defeated of the micro-control unit 1
Enter direct current, partially installing capacitor CbiasWith input resistance RRXRealize low-pass filter together to further filter out ripple interference.This reality
It applies in example, the first coupled capacitor CRX_P, the second coupled capacitor CRX_NWith biasing resistor RbiasHigh-pass filter can be formed, with filter
The DC voltage generated except detecting circuit.
Referring to Fig. 5 and Fig. 6, referring also to Fig. 4, in Fig. 5 and Fig. 6 embodiment, the Nomenclature Composition and Structure of Complexes of other parts circuit with
Embodiment shown in Fig. 4 is identical, in Fig. 5, with embodiment illustrated in fig. 4 the difference is that, of transmission circuit 2 in the present embodiment
It is transformer matching circuitry with circuit 22, such as the match circuit 22 can be 5 match circuit of balun or transformer.In Fig. 6,
Difference with embodiment illustrated in fig. 5 is, is connected between balun or 5 match circuit of transformer and EMC filter unit by transmission line 6
It connects, which for example can be parallel double conducting wire, parallel more conducting wires, coaxial line or strip line, can select according to actual needs
It selects, it is without limitation, to facilitate the case where needing more distantly located antenna, so that the present invention is using more flexible and convenient.
According to a further aspect of the invention, a kind of card reader is additionally provided.It includes above-mentioned R-T unit, and the card reader is for example
For near-field communication (Near Field Communication, NFC) card reader, high frequency RFID card reader or card reader of ID card
Deng.Compared to the prior art, the card reader with above-mentioned R-T unit can effectively increase card reading under the premise of power is constant
Distance.
The present invention reduces the property of R-T unit circuit by improving the signal quality of detecting circuit using differential signal
It can require.As shown in Fig. 4, Fig. 5 and Fig. 6, the detecting circuit in the present invention is equivalent to while including that a high-pass filter comes
The DC voltage of detecting circuit generation is filtered out, while increasing a low-pass filter to further filter out ripple interference signal,
Near-field communication R-T unit signal carrier in the prior art can be effectively reduced and interfere feelings that are big and influencing R-T unit sensitivity
Scape.Unlike the prior art, the present invention takes full advantage of the symmetry of match circuit and EMC filter circuit, it can be seen that
Receiving interface RX passes through CRX_pAnd CRX_nV is converged toCombEnd, above structure of the invention is in the base for increasing seldom component
Following effect is brought on plinth：
Reduce the interference of carrier wave ripple；Balance output and received load；The ripple frequency of detection is increased one times,
It is more easier to be filtered out by next stage baseband amplifier；And improve the sensitivity of R-T unit.It thus can effectively improve transmitting-receiving
The communication distance of device allows the card reading distance of card reader to reach operating distance of the RFID in minimum power.
It should be noted that, in two element " connections ", the two elements can directly connect in above each embodiment description
It connects, can also be connected indirectly by one or more intermediary element/media.The mode of two elements connection may include contact side
Formula or cordless.Those skilled in the art can carry out equivalencing or modification to example described above connection type,
Such substitution or modification is each fallen in the protection scope of the application.
Although describing example embodiment by reference to attached drawing here, it should be understood that above example embodiment are only exemplary
, and be not intended to limit the scope of the invention to this.Those of ordinary skill in the art can be it is characterized in that carry out each
Kind changes and modification, is made without departing from the scope of the present invention and spiritual.All such changes and modifications are intended to be included in appended power
Benefit requires within required the scope of the present invention.
In the instructions provided here, numerous specific details are set forth.It is to be appreciated, however, that implementation of the invention
Example can be practiced without these specific details.In some instances, well known method, structure is not been shown in detail
And technology, so as not to obscure the understanding of this specification.
It will be understood to those skilled in the art that any combination pair can be used other than mutually exclusive between feature
All features disclosed in this specification (including adjoint claim, abstract and attached drawing) and so disclosed any method
Or all process or units of equipment are combined.Unless expressly stated otherwise, this specification (is wanted including adjoint right
Ask, make a summary and attached drawing) disclosed in each feature can be replaced with an alternative feature that provides the same, equivalent, or similar purpose.
In addition, it will be appreciated by those of skill in the art that although some embodiments described herein include other embodiments
In included certain features rather than other feature, but the combination of the feature of different embodiments mean it is of the invention
Within the scope of and form different embodiments.For example, in detail in the claims, embodiment claimed it is one of any
Can in any combination mode come using.
It should be noted that the above-mentioned embodiments illustrate rather than limit the invention, and ability
Field technique personnel can be designed alternative embodiment without departing from the scope of the appended claims.In the claims,
Any reference symbol between parentheses should not be configured to limitations on claims.Word "comprising" does not exclude the presence of not
Element or step listed in the claims.Word "a" or "an" located in front of the element does not exclude the presence of multiple such
Element.The present invention can be by means of including the hardware of several different elements and being come by means of properly programmed computer real
It is existing.In the unit claims listing several devices, several in these devices can be through the same hardware branch
To embody.The use of word first, second, and third does not indicate any sequence.These words can be explained and be run after fame
Claim.
The above description is merely a specific embodiment or to the explanation of specific embodiment, protection of the invention
Range is not limited thereto, and anyone skilled in the art in the technical scope disclosed by the present invention, can be easily
Expect change or replacement, should be covered by the protection scope of the present invention.Protection scope of the present invention should be with claim
Subject to protection scope.
Claims (11)
1. a kind of R-T unit, which is characterized in that including：Micro-control unit, transmission circuit, the first detecting circuit and the second detection
Circuit,
First detecting circuit is connect with the first node in the transmission circuit, second detecting circuit and the transmitting-receiving
Second node connection in circuit, the output signal of the first node and the second node are differential signal, described first
The parallel circuit of detecting circuit and second detecting circuit is connect with the receiving interface of the micro-control unit,
The transmission circuit is connect with the differential transmission interface of the micro-control unit.
2. R-T unit according to claim 1, which is characterized in that first detecting circuit includes the be connected in series
One coupled capacitor, the first filter circuit and the first one-way conduction circuit, second detecting circuit include second be connected in series
Coupled capacitor, the second filter circuit and the second one-way conduction circuit.
3. R-T unit according to claim 2, which is characterized in that the first end of first one-way conduction circuit to
Two end forward conductions, the first end of second one-way conduction circuit to second end forward conduction, the first one-way conduction electricity
The first end on road is connect with the first node, and the first end of second one-way conduction circuit is connect with the second node.
4. R-T unit according to claim 3, which is characterized in that first filter circuit includes the first filter capacitor
The first parallel circuit formed with the first load resistance, and/or, second filter circuit includes the second filter capacitor and second
Second parallel circuit of load resistance composition.
5. R-T unit according to claim 4, which is characterized in that the first end of first coupled capacitor and described
The first end of two coupled capacitors is connect with the receiving interface,
First one-way conduction circuit includes the first detector diode, the anode and described first of first detector diode
Node connection, the cathode of first detector diode are connect with the first end of first parallel circuit, and described first is in parallel
The first end of circuit is also connect with the second end of first coupled capacitor, the second end ground connection of first parallel circuit；With
And
Second one-way conduction circuit includes the second detector diode, the anode and described second of second detector diode
Node connection, the cathode of second detector diode are connect with the first end of second parallel circuit, and described second is in parallel
The first end of circuit is also connect with the second end of second coupled capacitor, the second end ground connection of second parallel circuit.
6. R-T unit according to any one of claim 1 to 5, which is characterized in that further include：
Input resistance, the first end of the input resistance are connect with the receiving interface, the second end of the input resistance and institute
The first detecting circuit is stated to connect with the parallel connected end of second detecting circuit.
7. R-T unit according to any one of claim 1 to 5, which is characterized in that it further include partially installing capacitor, it is described inclined
It is in parallel with the biasing resistor in the biasing circuit of the micro-control unit to set capacitor.
8. R-T unit according to claim 7, which is characterized in that the micro-control unit is provided with biasing interface, institute
Biasing resistor is stated to be arranged outside the micro-control unit and be connected between the biasing interface and the receiving interface, it is described
Biasing resistor is used to bias the input direct-current of the micro-control unit.
9. R-T unit according to any one of claim 1 to 5, which is characterized in that the transmission circuit includes electromagnetism
Compatible filter unit, match circuit and antenna.
10. R-T unit according to any one of claim 1 to 5, which is characterized in that the match circuit be balun/
Transformer matching circuitry.
11. a kind of card reader, which is characterized in that the card reader includes receipts described in any one of the claims 1-10
Transmitting apparatus.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810358461.4A CN108875436B (en) | 2018-04-20 | 2018-04-20 | Receiving and transmitting device and card reader |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810358461.4A CN108875436B (en) | 2018-04-20 | 2018-04-20 | Receiving and transmitting device and card reader |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN108875436A true CN108875436A (en) | 2018-11-23 |
| CN108875436B CN108875436B (en) | 2024-06-11 |
Family
ID=64326407
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201810358461.4A Active CN108875436B (en) | 2018-04-20 | 2018-04-20 | Receiving and transmitting device and card reader |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN108875436B (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109299626A (en) * | 2018-10-29 | 2019-02-01 | 丁天威 | A kind of RFID card reader R-T unit and system |
Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0264920A2 (en) * | 1986-10-21 | 1988-04-27 | Csk Corporation | Tracking method and apparatus for optical recording medium |
| JP2005044298A (en) * | 2003-07-25 | 2005-02-17 | Fuji Xerox Co Ltd | Tag information reading method and device |
| CN101404067A (en) * | 2008-08-19 | 2009-04-08 | 周必友 | UHF active-mode active electronic label communication system |
| CN101529439A (en) * | 2006-10-19 | 2009-09-09 | Nxp股份有限公司 | Transceiving circuit for contactless communication |
| CN101957908A (en) * | 2010-07-26 | 2011-01-26 | 深圳市远望谷信息技术股份有限公司 | Method and device for RFID (Radio Frequency Identification) reader-writer antenna receiving |
| CN203299838U (en) * | 2013-06-27 | 2013-11-20 | 深圳拓邦股份有限公司 | Card reading circuit and card reader |
| CN106096697A (en) * | 2016-06-17 | 2016-11-09 | 广州中大微电子有限公司 | A kind of RFID Micro Energy Lose high sensitivity demodulator circuit |
| CN208298191U (en) * | 2018-04-20 | 2018-12-28 | 北京旷视科技有限公司 | A kind of R-T unit and card reader |
-
2018
- 2018-04-20 CN CN201810358461.4A patent/CN108875436B/en active Active
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0264920A2 (en) * | 1986-10-21 | 1988-04-27 | Csk Corporation | Tracking method and apparatus for optical recording medium |
| JP2005044298A (en) * | 2003-07-25 | 2005-02-17 | Fuji Xerox Co Ltd | Tag information reading method and device |
| CN101529439A (en) * | 2006-10-19 | 2009-09-09 | Nxp股份有限公司 | Transceiving circuit for contactless communication |
| CN101404067A (en) * | 2008-08-19 | 2009-04-08 | 周必友 | UHF active-mode active electronic label communication system |
| CN101957908A (en) * | 2010-07-26 | 2011-01-26 | 深圳市远望谷信息技术股份有限公司 | Method and device for RFID (Radio Frequency Identification) reader-writer antenna receiving |
| CN203299838U (en) * | 2013-06-27 | 2013-11-20 | 深圳拓邦股份有限公司 | Card reading circuit and card reader |
| CN106096697A (en) * | 2016-06-17 | 2016-11-09 | 广州中大微电子有限公司 | A kind of RFID Micro Energy Lose high sensitivity demodulator circuit |
| CN208298191U (en) * | 2018-04-20 | 2018-12-28 | 北京旷视科技有限公司 | A kind of R-T unit and card reader |
Non-Patent Citations (1)
| Title |
|---|
| 丁敬峰: ""基于GaAs工艺的光通信用新型超高速分接器集成电路研究"", 《中国博士学位论文电子期刊信息科技辑》, pages 135 - 30 * |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109299626A (en) * | 2018-10-29 | 2019-02-01 | 丁天威 | A kind of RFID card reader R-T unit and system |
| CN109299626B (en) * | 2018-10-29 | 2022-03-15 | 丁天威 | RFID card reader receiving and sending device and system |
Also Published As
| Publication number | Publication date |
|---|---|
| CN108875436B (en) | 2024-06-11 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| KR101674776B1 (en) | Contactless communication method with negative modulation | |
| CN209419611U (en) | Amplifying circuit, near field communication controller and near-field communication transceiver circuit | |
| US10200091B2 (en) | RF front end module and near field communication device | |
| CN102013927A (en) | Communication equipment and antenna testing device | |
| CN103597660A (en) | Arrangement of antennas transmitting and receiving an electromagnetic field | |
| CN103608827A (en) | Method, circuit, and device for contactless communication with activated transmission | |
| CN101552614B (en) | Single antenna tuning circuit used for near field communication equipment | |
| EP3553958B1 (en) | Rf front end module and near field communication device | |
| CN208298191U (en) | A kind of R-T unit and card reader | |
| CN108875436A (en) | A kind of R-T unit and card reader | |
| CN109327245A (en) | A kind of R-T unit and card reader | |
| CN102622645B (en) | Radio frequency front end of radio frequency identification (RFID) electronic tag | |
| CN104123571A (en) | Carrier wave offset circuit based on RFID reader-writer, and RFID reader-writer | |
| WO2009096815A1 (en) | Connection sensor for identifying the port of a plugboard | |
| CN104899534A (en) | Non-contact type card reader | |
| CN206506524U (en) | A kind of signal sending and receiving equipment | |
| CN201549600U (en) | Single-antenna tuning circuit for near field communication equipment | |
| CN109299626B (en) | RFID card reader receiving and sending device and system | |
| CN214504421U (en) | Novel antenna and reader-writer thereof | |
| CN208384607U (en) | A kind of RFID tag reader and RFID tag read-write system | |
| CN202159357U (en) | Super-small high-frequency radio frequency identification devices (RFID) portable reader-writer module | |
| CN106203207B (en) | Communication device | |
| CN107070481A (en) | A kind of signal sending and receiving equipment | |
| CN109635607B (en) | A kind of millimeter wave fairing realized towards single-chip | |
| CN107491707A (en) | A kind of ultrahigh frequency radio frequency identification (RFID) reader radio circuit |
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 |