CN102196605B - Mobile radio frequency device, radio frequency IC (Integrated Circuit) card and radio frequency storage card - Google Patents

Mobile radio frequency device, radio frequency IC (Integrated Circuit) card and radio frequency storage card Download PDF

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CN102196605B
CN102196605B CN201010124327.1A CN201010124327A CN102196605B CN 102196605 B CN102196605 B CN 102196605B CN 201010124327 A CN201010124327 A CN 201010124327A CN 102196605 B CN102196605 B CN 102196605B
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frequency
low
card
circuit
mobile radio
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CN102196605A (en
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沈爱民
余运波
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Nationz Technologies Inc
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Nationz Technologies Inc
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Priority to CN201010124327.1A priority Critical patent/CN102196605B/en
Priority to PCT/CN2010/071416 priority patent/WO2011113216A1/en
Priority to ARP110100802A priority patent/AR080399A1/en
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    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06Q—INFORMATION AND COMMUNICATION TECHNOLOGY [ICT] SPECIALLY ADAPTED FOR ADMINISTRATIVE, COMMERCIAL, FINANCIAL, MANAGERIAL OR SUPERVISORY PURPOSES; SYSTEMS OR METHODS SPECIALLY ADAPTED FOR ADMINISTRATIVE, COMMERCIAL, FINANCIAL, MANAGERIAL OR SUPERVISORY PURPOSES, NOT OTHERWISE PROVIDED FOR
    • G06Q20/00—Payment architectures, schemes or protocols
    • G06Q20/30—Payment architectures, schemes or protocols characterised by the use of specific devices or networks
    • G06Q20/32—Payment architectures, schemes or protocols characterised by the use of specific devices or networks using wireless devices
    • G06Q20/327—Short range or proximity payments by means of M-devices
    • G06Q20/3278—RFID or NFC payments by means of M-devices
    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06K—GRAPHICAL DATA READING; PRESENTATION OF DATA; RECORD CARRIERS; HANDLING RECORD CARRIERS
    • G06K19/00—Record carriers for use with machines and with at least a part designed to carry digital markings
    • G06K19/06—Record carriers for use with machines and with at least a part designed to carry digital markings characterised by the kind of the digital marking, e.g. shape, nature, code
    • G06K19/067—Record carriers with conductive marks, printed circuits or semiconductor circuit elements, e.g. credit or identity cards also with resonating or responding marks without active components
    • G06K19/07—Record carriers with conductive marks, printed circuits or semiconductor circuit elements, e.g. credit or identity cards also with resonating or responding marks without active components with integrated circuit chips
    • G06K19/0723—Record carriers with conductive marks, printed circuits or semiconductor circuit elements, e.g. credit or identity cards also with resonating or responding marks without active components with integrated circuit chips the record carrier comprising an arrangement for non-contact communication, e.g. wireless communication circuits on transponder cards, non-contact smart cards or RFIDs
    • G06K19/0724—Record carriers with conductive marks, printed circuits or semiconductor circuit elements, e.g. credit or identity cards also with resonating or responding marks without active components with integrated circuit chips the record carrier comprising an arrangement for non-contact communication, e.g. wireless communication circuits on transponder cards, non-contact smart cards or RFIDs the arrangement being a circuit for communicating at a plurality of frequencies, e.g. for managing time multiplexed communication over at least two antennas of different types
    • 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
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01Q—ANTENNAS, i.e. RADIO AERIALS
    • H01Q7/00—Loop antennas with a substantially uniform current distribution around the loop and having a directional radiation pattern in a plane perpendicular to the plane of the loop

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  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Theoretical Computer Science (AREA)
  • Business, Economics & Management (AREA)
  • Computer Hardware Design (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • Accounting & Taxation (AREA)
  • Strategic Management (AREA)
  • General Business, Economics & Management (AREA)
  • Near-Field Transmission Systems (AREA)

Abstract

The invention relates to a mobile radio frequency device, a radio frequency IC (Integrated Circuit) card and a radio frequency storage card, wherein the mobile radio frequency device comprises at least one low-frequency magnetic induction circuit, at least one low-frequency amplifying circuit, at least one threshold judging and demodulating circuit, at least one second main processor, at least one radio frequency transceiver circuit and at least one radio frequency antenna, wherein the low-frequency magnetic induction circuit, the low-frequency amplifying circuit, the threshold judging and demodulating circuit, the second main processor, the radio frequency transceiver circuit and the radio frequency antenna are sequentially connected in series; and a low-frequency receiving link formed by the low-frequency magnetic induction circuit, the low-frequency amplifying circuit and the threshold judging and demodulating circuit works at the frequency below the highest frequency f0 of the calibration-free work of a previously selected system. The mobile radio frequency device can ensure that a mobile terminal provided with the mobile radio frequency device realizes card swiped transactions, i.e. electronic payment and the like.

Description

Mobile radio device, RF IC card and radio frequency storage card
Technical field
The present invention relates to the communications field, relate in particular to a kind of mobile radio device, RF IC card and radio frequency storage card.
Background technology
Universal along with mobile terminal, utilizes mobile terminal to carry out the application demand of mobile terminal payment very urgent, has had at present multiple implementation, but has respectively had shortcoming.Current, there is the subscriber identification module SIM(Subscriber Identity Module in mobile terminal) increase radio-frequency enabled (being called radio-frequency SIM card) on card or on Mobile terminal main board, increase the method that proximity communication module is realized mobile terminal short-range communication, the latter is called NFC (Near Field Communication, near-field communication), the appearance of these methods make mobile terminal become one can supplement with money, consume, the super intelligent terminal of transaction and authentication, greatly met the active demand in market.
Wherein, mobile terminal based on radio-frequency SIM card closely solution is simple with it, without advantages such as change mobile terminals, paid close attention to widely, in this scheme, radio-frequency SIM card adopts UHF(Ultra High Frequency, hyperfrequency) technology, because UHF particularly adopts (the i.e. industry of 2.4GHz ISM common frequency band, science and medical frequency range) radio-frequency SIM card, its operating frequency is very high, antenna small-sized, in SIM card, place small-sized antenna and just can launch the signal of sufficient intensity, even if radio-frequency SIM card is embedded in mobile terminal internal radio frequency, signal still can transmit from mobile terminal, in card reader, adopt RF (the Radio Frequency of industry main flow, radio frequency) transceiving chip can be without the extra reliable reception that amplifies to the radiofrequency signal of most mobile terminals, thereby needn't carrying out any structural change to existing mobile terminal, realization just can make mobile terminal possess short-range communication function.But, because internal structure difference causes radiofrequency signal transmission effects, there is very large difference in different mobile terminal, strong its radio-frequency SIM card radio frequency communication distance of mobile terminal of transmission may reach the distance of several meters far away, and its communication distance of radio frequency SIM card of mobile terminal a little less than transmission is only to reach several centimetres.Radio-frequency SIM card is the greatest differences to RF signal attenuation for fear of different mobile terminal, must calibrate mobile terminal, namely the attenuation parameter of mobile terminal must be recorded in card before use.Needing calibration is the subject matter of radio-frequency SIM card.
The non-contact card Technology Evolution of the technology NFC of another mobile payment based on ISO14443 standard, both basic points are all to adopt the magnetic field of 13.56MHz to transmit signal and energy.The subject matter of NFC technology has:
1. mobile terminal must be transformed and reliable two-way data communication could be realized, the field coil of NFC can not be integrated into SIM card or SD card (Secure Digital Memory Card, in the card of the used for mobile terminal such as safety digital storage card)/TF (TransFLash, flash memory) card.
Under 13.56MHz frequency, between card reader and card, adopt the mode interactive signal of inductance coil coupling and transmit energy, card reader needs transferring energy and 13.56MHz amplitude-modulated signal simultaneously to the direction of card, to blocking the dimensioned area of upper receiving coil, all has higher requirements; Snap into the direction of card reader, the mode that the load-modulate mode of card dependence short circuit and the upper coil of open circuit card rather than dependence external energy directly send field intensity is to card reader transmission of information, due to the more high information that is more beneficial to the transmission of card reader decoding card of coupling coefficient that load modulation signal requires to block coil and card reader coil, this mode has further improved blocking the requirement of upper antenna size and area.On the one hand, because 13.56MHz frequency is lower, the size of coupling coil is relatively large in addition.Amid all these factors, NFC requires the aerial coil in mobile terminal enough large, this size can not be put into the card of the used for mobile terminal such as SIM card or SD/TF card completely, moreover, reception and the load-modulate effect of the metal on mobile terminal and other conductive body meeting severe jamming antenna, in order to reach the communication effect that near-field communication is good, the transformation that must customize mobile phone, makes the effect of antenna reach best.Transformation point for example, is put into the multiturn antenna of card on the cell rear cover of mobile terminal, or by flexible PCB, antenna is guided to cell backside from terminal mainboard, and the area of antenna is suitable with common batteries size, and in addition, the bonnet of mobile phone can not be metal material.
The 13.56MHz frequency that 2.NFC is used need to be calibrated and could control for distance.
Even if there is the antenna of a kind of NFC can change in any mobile terminal, because it uses 13.56MHz frequency, this frequency signal is running into metal and the strong eddy current effect of other conducting objects cognition formation, signal strength signal intensity can change along with mobile terminal structure, thereby on NFC card reception antenna, form the huge fluctuation of field intensity, cannot carry out controlling without the distance of calibration.
Fig. 1 is that coil receiving circuit is put into various mobile terminals, voltage-the distance Curve of testing the in the situation that of keeping 13.56MHz carrier wave constant on same 14443POS machine, wherein signal strength values is the value of reception antenna induced voltage after necessary amplification, it is constant that multiplication factor keeps, and only needs to pay close attention to the relative variation of intensity distance.Can find out, the field intensity difference >30dB that different terminals receives, the field intensity of same terminal from 1cm to 10cm is changed to 25dB left and right, the field intensity that mobile phone difference causes changes and to 10cm, apart from the field intensity in control range, changes at 1cm over terminal, therefore cannot adopt same thresholding to carry out distance to each terminal and control, namely cannot realize without calibrated distance and controlling.
Summary of the invention
Technical problem to be solved by this invention is to provide a kind of mobile radio device, and the mobile terminal that makes to be provided with this mobile radio device can be realized paying by mails and wait the transaction of swiping the card.
For solving the problems of the technologies described above, the present invention proposes a kind of mobile radio device, comprise at least one low-frequency magnetic sensor circuit, at least one low-frequency amplifier circuit, at least one thresholding judgement and demodulator circuit, at least one second primary processor, at least one radio-frequency (RF) transmit-receive circuit and at least one radio-frequency antenna, described low-frequency magnetic sensor circuit, low-frequency amplifier circuit, thresholding judgement and demodulator circuit, the second primary processor, radio-frequency (RF) transmit-receive circuit, radio-frequency antenna connection in sequential series; Wherein, the low frequency receiver that described low-frequency magnetic sensor circuit, low-frequency amplifier circuit, thresholding judgement and demodulator circuit form works in previously selected system without the frequency below the highest frequency f0 of calibration operation.
Further, above-mentioned mobile radio device also can have following characteristics, described low-frequency magnetic sensor circuit is coil, low-frequency magnetic sensor circuit conversion gain is to swipe the card farthest apart from corresponding systemic presupposition value with the applied system of mobile radio device place mobile terminal with the product of the multiplication factor of low-frequency amplifier circuit, the volume of described low frequency receiver depends on the multiplication factor of described low-frequency magnetic sensor circuit conversion gain and low-frequency amplifier circuit, the volume of low frequency receiver increases with the increase of low-frequency magnetic sensor circuit conversion gain, or the minimizing with low-frequency amplifier circuit multiplication factor increases.
Further, above-mentioned mobile radio device also can have following characteristics, described system without the highest frequency f0 of calibration operation in ultra-low frequency frequency range or very low frequency frequency range or low frequency frequency range, the frequency range of described ultra-low frequency frequency range is 300Hz～3000Hz, the frequency range of described very low frequency frequency range is 3KHz～30KHz, and the frequency range of described low frequency frequency range is 30KHz～300KHz.
Further, above-mentioned mobile radio device also can have following characteristics, and described system is 300Hz～50KHz without the residing frequency range of highest frequency f0 of calibration operation.
Further, above-mentioned mobile radio device also can have following characteristics, and described system is 500Hz, 1KHz, 1.5KHz, 2KHz, 2.5KHz, 3KHz, 4KHz, 5KHz, 10KHz, 20KHz or 30KHz without the highest frequency f0 of calibration operation.
Further, above-mentioned mobile radio device also can have following characteristics, and described thresholding judgement and demodulator circuit are comprised of interconnective comparison circuit and decoding circuit.
Further, above-mentioned mobile radio device also can have following characteristics, and described thresholding judgement and demodulator circuit are comprised of the comparison circuit being connected in turn, demodulator circuit and decoding circuit.
Further, above-mentioned mobile radio device also can have following characteristics, and described low-frequency magnetic sensor circuit is PCB coil, enamel wire coil, hall device or giant reluctivity device.
Further, above-mentioned mobile radio device also can have following characteristics, and described mobile radio device is placed in mobile terminal.
Further, above-mentioned mobile radio device also can have following characteristics, and described mobile radio device is placed in SIM card, UIM card, usim card, TF card, SD card or the mmc card in mobile terminal.
Further, above-mentioned mobile radio device also can have following characteristics, and the processor in described the second primary processor and SIM/UIM/USIM/TF/SD/MMC card is same common processor.
Further, above-mentioned mobile radio device also can have following characteristics, and described mobile terminal is mobile phone, personal digital assistant PDA or notebook computer.
For solving the problems of the technologies described above, the invention allows for a kind of RF IC card, comprise the mobile radio device described in above-mentioned any one.
For solving the problems of the technologies described above, the invention allows for a kind of radio frequency storage card, comprise the mobile radio device described in above-mentioned any one.
Mobile radio device of the present invention, can make the mobile terminal realization E-Payment that is provided with this mobile radio device wait the transaction of swiping the card.
Accompanying drawing explanation
Fig. 1 is that coil receiving circuit is put into various mobile terminals, the voltage-distance Curve of testing the in the situation that of keeping 13.56MHz carrier wave constant on same 14443POS machine;
Fig. 2 be near field communication method of the present invention system without the selective system structured flowchart of the highest frequency f0 of calibration operation;
Fig. 3 serves as reasons and determines that apart from controlling target (Din, Dv) the total reception of system detects scope range of the fluctuation of voltage δ aschematic diagram;
Fig. 4 is δ schematic diagram between exemplary terminal and barrier voltage distances curve and wave zone thereof;
Fig. 5 is the voltage distances curve of frequency f 5 kinds of typical mobile terminals while being 3.3KHz;
The voltage oscillogram of receiver voltage signal when Fig. 6 is receiver voltage signal during direct baseband transmission without modulation that detects of mobile radio device inside and sinusoidal wave FSK modulation;
Fig. 7 is the computational methods schematic diagram of reference voltage distance Curve;
Fig. 8 is the structure chart of near field communication system in the embodiment of the present invention;
Fig. 9 is card reader low frequencies part schematic diagram;
Figure 10 is card reader low-frequency data frame format schematic diagram;
Figure 11 is that coil receiving circuit is put into various mobile terminals, launches the voltage distances curve of testing under constant 1KHz magnetic field condition by signal source by low frequencies coil;
Figure 12 is the structure chart of RF IC card in the embodiment of the present invention;
Figure 13 is the 4 circle pcb copper sheet coil antenna structure views that are applied to SIM card;
Figure 14 is the different manchester encoding form of 5bit data 11010 and field intensity, coil receiver voltage oscillogram;
Figure 15 is the constant amplitude figure that the interior sim clamping of the low frequency magnetic field mobile terminal of 1KHz is received;
Figure 16 is the 4 circle pcb coil antenna structure schematic diagrames that are applied to TF card;
Figure 17 is error control system block diagram.
Embodiment
At this, first illustrate, below the terminal that occurred herein refers to be mounted with the terminal of mobile radio device under default situations, and refer to the terminal that can move, it is mobile terminal, as mobile phone etc., distance refers to the distance between card reader and mobile radio device, is also the distance between card reader and the terminal that is mounted with mobile radio device.
The present invention is directed to radio-frequency unit and (be especially built in the radio-frequency card in terminal, as radio-frequency SIM card) distance control of closely concluding the business with card reader arrangement, proposed a kind of by the card reader with low frequency alternating magnetic field emission function and radiofrequency signal transmission-receiving function and the near field communication system of the corresponding mobile radio installation composition with low frequency alternating magnetic field induction receiving function and radiofrequency signal transmission-receiving function with it, and the near field communication method corresponding with this system.The present invention utilizes low frequency alternating magnetic field to penetrate feature that different terminals difference in attenuation is little to carry out distance and control, and utilizes high-frequency radio frequency can effectively penetrate terminal and completes high-speed bidirectional communication and conclude the business.The distance that system completes without calibration by pre-set thresholding decision method detects and controls, be that card reader is according to default emission parameter transmitting low frequency alternating magnetic field signal, mobile radio device detects this field signal and is enlarged into the voltage signal of the constant amplitude corresponding with distance in each range points, and then judge by predefined voltage threshold Vt whether terminal enters predefined coverage interval (coverage interval also allows the scope of swiping the card), this voltage threshold Vt is identical to all terminals, without calibration.The present invention completes unique binding of card reader and mobile radio device by the method for low frequency one-way communication and the combination of RF both-way communication, complete the communication of two-way high speed big data quantity after binding by radio-frequency channel.System of the present invention can realize the terminal that the contains mobile radio device mobile phone of radio-frequency SIM card (as be equipped with) and be controlled in prescribed limit reliably with the data communication distance (also i.e. transaction distance) of card reader, and without terminal is calibrated.
Below in conjunction with accompanying drawing, principle of the present invention and feature are described, example, only for explaining the present invention, is not intended to limit scope of the present invention.
Near field communication method of the present invention, be applied to comprise the near field communication system of at least one card reader and at least one mobile radio device, comprise following step a, step b, step c and four steps of steps d, respectively each step be specifically described below:
Step a, card reader is according to default emission parameter transmitting low frequency alternating magnetic field signal, in this low frequency alternating magnetic field signal, carry the identification information of this card reader, wherein, emission parameter comprises the frequency of low frequency alternating magnetic field signal, and this frequency is equal to or less than system without the highest frequency f0 of calibration operation; Wherein, identification information can be identification code ID.
Here it should be noted that, the frequency of this step medium and low frequency alternating magnetic field signal refers to that the high-end frequency cutoff of three dB bandwidth on the frequency spectrum of described low-frequency alternating signal puts corresponding frequency.
Low frequency alternating magnetic field frequency is lower, less through the difference decaying after various types of terminals, utilizes this characteristic, and in frequency selective system (as shown in Figure 2), the selected enough little frequency of difference, controls to realize without calibrated distance.Adopt standard signal source to send low frequency alternating magnetic field signal by the emission of magnetic field coil of standard, at each typical mobile terminal and inner this low frequency alternating magnetic field signal that receives of barrier, adjust tranmitting frequency until find frequency f0, make the voltage that mobile radio device (being loaded in mobile terminal) receives (this voltage be the constant amplitude corresponding with distance that obtained after amplifying by low frequency alternating magnetic field signal voltage signal) under range transmission coil plane central point same distance condition, field intensity difference between different terminals and barrier is substantially equal to the fluctuation range δ of setting tthis frequency f0 and be that system is without the frequency range of calibration operation lower than the frequency range of this frequency f0, do not need to calibrate any terminal in any system, working frequency points (being the frequency of aforesaid low frequency alternating magnetic field signal) is higher than f0, system needs calibration, conventionally working frequency points is more higher than f0, needs the terminal of calibration more, and the complexity of calibration is higher.Frequency is selected is disposable work, once selected, in use without change.
Fig. 2 be near field communication method of the present invention system without the selective system structured flowchart of the highest frequency f0 of calibration operation, as shown in Figure 2, consisting of of frequency selective system: transmitting system is comprised of signal source 505 and low frequency magnetic field transmitting coil 504, receiving system is by typical mobile terminal 501 and barrier, signal strength test instrument 503(voltmeter, oscilloscope, frequency spectrograph etc.) form, mobile terminal 501 inside have low frequency receiver module 502.Signal source 505 can produce the signal of various frequencies, waveform and amplitude accurately.The principle that frequency is selected is: signal source 505 produces the sine wave signal that fixed amplitude frequency is f, by transmitting coil 504, send, low frequency receiver module 502 is placed on selected typical mobile terminal 501 or barrier is inner, the low frequency signal receiving is received signal strength tester 503 by dedicated signal lines, the voltage that 503 tests of signal strength test instrument receive.The distance that changes mobile terminal can obtain this mobile terminal or the detection voltage of barrier under frequency f condition with the curve (hereinafter referred to as voltage distances curve) of variable in distance, change the curve that mobile terminal or barrier can obtain a plurality of terminals, change frequency f and also can obtain different curves.
In step a, system is determined by following step without the highest frequency f0 of calibration operation:
Step 101, determines distance control target (Din, Dv), wherein Din represents that within the scope of 0～Din, all terminals are guaranteed to swipe the card, Dv represents apart from fluctuation range, in the scope that distance is Din～(Din+Dv), all allows to swipe the card, and distance is greater than Din+Dv scope and does not allow to swipe the card;
For example the following all terminals of (5cm, 5cm) expression 5cm are guaranteed to swipe the card, and 5cm～10cm allows to swipe the card, and surpassing 10cm can not swipe the card.Distance is controlled target and is determined by concrete application.(0～Din+Dv) is called apart from control range.
Step 102, determines the interior fluctuation range δ that detects voltage of mobile radio device that card reader causes r;
The fluctuation of card reader low frequencies circuit parameter forms the fluctuation of transmitting field intensity, causes the fluctuation that detects voltage in mobile radio device, and this parameter comprises the fluctuation of transmitting driving voltage, coil parameter fluctuation, temperature impact etc.δ rby Reader Design and production link, controlled, this fluctuation can be calibrated at production link, because low frequencies circuit work frequency is very low, and common δ rcan controlledly make fine, for example, in 4dB.
Step 103, determines the fluctuation range δ of the detection voltage that mobile radio device causes itself c;
The fluctuation of the final detection output voltage that the low frequency receiving circuit of mobile radio device parameter fluctuation own causes, this parameter comprises reception antenna error, amplifier gain error, comparator or AD error, temperature impact and noise etc.δ cby mobile radio device, designed and production link is controlled, this fluctuation can be calibrated at production link, because mobile radio device low frequency receiving circuit operating frequency is very low, and δ conventionally ccan controlledly make fine, for example, in 4dB.
Step 104, under f frequency, test the voltage distances curve of each exemplary terminal and barrier, wherein f frequency is the arbitrary frequency in ultra-low frequency frequency range or very low frequency frequency range or low frequency frequency range, the frequency range of ultra-low frequency frequency range is 300Hz～3000Hz, the frequency range of very low frequency frequency range is 3KHz～30KHz, and the frequency range of low frequency frequency range is 30KHz～300KHz;
Before carrying out this step 104, first to do a preparation, i.e. selected exemplary terminal and typical barrier.The number of the selection principle Main Basis terminal metal of exemplary terminal or conductive structure is chosen, metal is more, decay larger, such as choosing plastic casing, metal shell, thick metal-back, thin metal-back, large scale terminal, small-sized terminals etc., the quantity of exemplary terminal is strictly restriction not, and choosing of exemplary terminal can cover the decay feature of terminal to low frequency alternating magnetic field signal substantially.Too large for fear of indivedual mobile terminal difference, can in application, add the authentication of mobile terminal model, the mobile terminal that every kind of needs support is paid to application has a go at the test of swiping the card, and confirms that the mobile terminal attenuation characteristic of this model meets the requirements.Typical case's barrier can be selected the mobile terminal common materials such as plastics, aluminium, copper, iron, stainless steel of the standard shape of unlike material, is placed on a kind of equivalent barrier as mobile terminal attenuation characteristic between card reader and mobile radio device and measures attenuating.
Step 105, controls target (Din, Dv) by distance and determines the fluctuation range δ that detects voltage in mobile radio device a, δ aequal on the voltage distances curve with average field-strength attenuation curve slope that the voltage distances curve by each exemplary terminal and barrier obtains the corresponding magnitude of voltage of Din point and (Din+Dv) put the poor of corresponding magnitude of voltage;
Fig. 3 serves as reasons and determines that apart from controlling target (Din, Dv) the total reception of system detects scope range of the fluctuation of voltage δ aschematic diagram.As shown in Figure 3, (Din+Dv) putting corresponding magnitude of voltage is V2, and the corresponding magnitude of voltage of Din point is V1, δ a=V1-V2.
Step 106, determines the fluctuation range δ that detects voltage in the mobile radio device being caused by terminal t, parameter δ trepresent interior scope range of the fluctuation of voltage, the δ of detecting of mobile radio device that terminal attenuation characteristic causes t=δ a-δ r-δ c;
Step 107, calculates between each exemplary terminal and barrier the maximum field strength difference δ (being called between wave zone again) in each range points in apart from control range, if δ is greater than δ t, reduce frequency f, go to step a4; If δ is less than δ t, improve frequency f, go to step a4; If δ equals δ t, current test frequency f equals system without the highest frequency f0 of calibration operation.
Fig. 4 is δ schematic diagram between exemplary terminal and barrier voltage distances curve and wave zone thereof.As shown in Figure 4, the voltage distances curve that maximum attenuation terminal or barrier are corresponding is called maximum attenuation curve, the voltage distances curve that minimal attenuation terminal or barrier are corresponding is called minimal attenuation curve, the region that maximum and minimal attenuation curve surround is called exemplary terminal and barrier voltage distances curve distribution is interval, any distance D corresponding voltage on minimal attenuation curve is V3, voltage corresponding on maximum attenuation curve is V4, δ=V3-V4.
So far, in the situation that limiting distance control target, system has just been decided without the highest frequency f0 of calibration operation.System can adopt the mode of modulation, also can adopt the mode of direct transmission baseband signal, as long as the highest f0 that is not more than of main frequency component of system works, distance is controlled just without calibration.
Illustrate the deterministic process of f0.Fig. 5 is the voltage distances curve of frequency f 5 kinds of typical mobile terminals while being 3.3KHz.As shown in Figure 5, system is (5cm, 5cm) apart from controlling target, and between system 0～10cm distance regions, the excursion of voltage is about 40dB, detects voltage fluctuation and is 4dB, be i.e. δ in the mobile radio device that card reader and mobile radio device cause r=δ c=4dB, δ a=20dB, δ t=δ a-δ r-δ c=12dB.Suppose all terminals that 5 kinds of terminals can representative system be used, check that the maximum fluctuation of curve in each range points approximates 12dB, so this system can be defined as f0=3.3KHz without the highest frequency f0 of calibration operation.
In step a, emission parameter can also comprise modulation system, coded system and transmitting magnetic flux density amplitude Br.The selected basic principle of emission parameter be guarantee the low frequency alternating magnetic field input that mobile radio device is launched card reader in each range points and amplify after signal be the voltage signal of the constant amplitude corresponding with distance.The voltage oscillogram of receiver voltage signal when Fig. 6 is receiver voltage signal during direct baseband transmission without modulation that detects of mobile radio device inside and sinusoidal wave FSK modulation, wherein, receiver voltage signal waveforms when a is the direct baseband transmission of nothing modulation, receiver voltage signal waveforms when b is sinusoidal wave FSK modulation.As shown in Figure 6, detectable voltage signals is the variation voltage signal that comprises demodulating information, this signal can be the ac voltage signal without DC component, can be also the voltage signal that has DC component, and constant amplitude refers to that the variation amplitude peak of alternating current component is constant between different transmission symbols.
Modulation system in emission parameter, coded system and transmitting magnetic flux density amplitude Br are selected to step a13 by following step a11:
Step a11, selected any one coded system without average DC component, Manchester code for example, Difference Manchester code, NRZ etc.;
Step a12, selection is without modulation system or the unconverted carrier modulation mode of amplitude, carrier modulation mode can be selected the unconverted modulation system of any one amplitude, such as carrier wave, can adopt sine wave, pulse, triangular wave etc., modulation system can be elected on-off keying method (OOK), phase-shift keying or frequency shift keying (FSK) etc. as; Employing is during without modulation system, and the baseband signal after coding directly drives and launched by transmitting coil through drive circuit;
Step a13, selected transmitting magnetic flux density amplitude Br, method is: in the selected operating frequency that is less than f0, under modulation system and coded system, the gain parameter that in the mobile radio device of first selecting pink noise terminal and being easy to realize, magnetic detects and amplifies, it is that distance control target farthest is Din+Dv distance that the mobile terminal that comprises mobile radio device is placed on from card reader, if mobile radio device adopts hall device, the magnetic conduction circuitry that giant reluctivity device etc. detect field strength values receives, card reader is launched the constant field signal of magnetic flux density amplitude of variation, if mobile radio device adopts the sensor circuit of the detection change rate of magnetic density such as coil to receive, card reader is launched the constant field signal of magnetic flux density rate of change amplitude (being differential amplitude), test card reader does not send the intrinsic noise voltage amplitude Vn that detects voltage under low frequency alternating magnetic field signal conditioning in mobile radio-frequency unit, then measure card reader and send the detection voltage Vr in the moving radio-frequency unit of low frequency alternating magnetic field time shift signal with selected modulation coding mode, select transmitting range value Bgate or differential range value B_RATEgate, make Vr/Vn>SNR, SNR is the signal to noise ratio of mobile radio device.The selection of SNR value is the bigger the better conventionally, it is excessive that but too conference causes card reader transmitted power, realize difficulty, it is definite that representative value can select SNR=10. to work as SNR, Br has just determined by the way, the magnetic conduction circuitry type difference of selecting according to system, and Br parameter value is divided into two kinds, hall device and giant reluctivity device receiving system are magnetic flux density amplitude thresholding Bgate, and coil receiving system is magnetic flux density rate of change amplitude thresholding B_RATEgate.
Step b, mobile radio device in each range points, receive, detect described low frequency alternating magnetic field signal and be enlarged into constant amplitude corresponding to distance voltage signal, and then it is interval whether to have entered default coverage by the terminal that default voltage threshold Vt judgement is mounted with described mobile radio device, described voltage threshold Vt is identical to being mounted with all terminals of described mobile radio device;
In step b, default voltage threshold Vt is definite to step 203 by following step 201, and prerequisite is determine that it is pulsation-free that card reader transmitting and mobile radio device receive, or the reception that both cause to detect voltage fluctuation much smaller than δ rand δ c:
Step 201, under selected emission parameter, measures the voltage distances curve of each exemplary terminal and barrier, and wherein, emission parameter comprises frequency, modulation system, coded system and the transmitting magnetic flux density amplitude Br of low frequency alternating magnetic field signal;
Step 202, asks for reference voltage distance Curve, and reference voltage distance Curve is the median of exemplary terminal and barrier curve, and it is all δ apart from the coboundary of exemplary terminal curve and the voltage amplitude of lower boundary t/ 2, as shown in Figure 7;
Step 203, detects voltage threshold Vt in selected mobile radio device, Vt value equals distance control target Din and (Din+Dv) and between corresponding magnitude of voltage, take respectively the median of the magnitude of voltage that dBmV is unit.As shown in Figure 7, the voltage corresponding to Din in reference voltage distance Curve is V5(dBmV), corresponding to the magnitude of voltage of (Din+Dv) point, be V6(dBmV), Vt=V5-(V5-V6)/2(dBmV).
Step c, if the voltage signal corresponding with the low frequency alternating magnetic field signal receiving is more than or equal to default voltage threshold Vt, the terminal that is mounted with mobile radio device has entered the default interval of effectively swiping the card, mobile radio device obtains the identification information of card reader from the low frequency alternating magnetic field signal receiving, and the identification information together with self sends card reader to by radio-frequency channel by it;
Steps d, card reader receives the information that mobile radio device transmits by radio-frequency channel, relatively in this information, whether the identification information of card reader is consistent with the identification information of self, if consistent with self identification information and the identification information of mobile radio device be combined as combination of address, with mobile radio device by the radio-frequency channel transaction of swiping the card.Herein, swiping the card transaction does not singly refer to pay by mails, can also be other communication processs that undertaken by radio-frequency channel, such as supplementing with money, consumption, authentication etc., the communication that the transaction general reference of swiping the card is herein undertaken by radio-frequency channel, especially refers to the communication of being undertaken by radio-frequency channel in short-range communication.
In the present invention, the frequency of low frequency alternating magnetic field signal is in ultra-low frequency frequency range or very low frequency frequency range or low frequency frequency range, and wherein, the frequency range of ultra-low frequency frequency range is 300Hz～3000Hz, the frequency range of very low frequency frequency range is 3KHz～30KHz, and the frequency range of low frequency frequency range is 30KHz～300KHz.Preferably, the frequency of low frequency alternating magnetic field signal can be 300Hz～50KHz.Preferably, the frequency of low frequency alternating magnetic field signal can be 500Hz, 1KHz, 1.5KHz, 2KHz, 2.5KHz, 3KHz, 4KHz, 5KHz, 10KHz, 20KHz or 30KHz.
Near field communication method of the present invention adopts the combination of low frequency magnetic field one-way communication and radio frequency electromagnetic field high-speed bidirectional communication, thereby has avoided adopting unique 13.56MHz frequency both-way communication and distance to control in NFC system and bring antenna problem and the problem such as terminal signaling difference in attenuation is large.In this method, it is aforesaid identification information by self unique ID r(that card reader is utilized low frequency half-duplex channel) pass to mobile radio device, mobile radio device returns to card reader after self unique ID c being attached to IDr by RF bidirectional passage, the correctness of the IDr that card reader relatively returns, and then realized unique binding of card reader and mobile radio device.After binding, card reader and mobile radio device adopt RF bidirectional passage to realize the communication of high speed big data quantity, until this transaction completes.
Near field communication method of the present invention has been realized the radio communication terminal that the contains mobile radio device mobile phone of radio-frequency SIM card (as be equipped with) and has been controlled in prescribed limit reliably with the data communication distance (also i.e. transaction distance) of card reader, and without terminal is calibrated.
In order to realize above-mentioned near field communication method, the invention allows for a kind of near field communication system.Near field communication system of the present invention comprises at least one card reader and at least one mobile radio device, wherein:
Card reader is for the emission parameter transmitting low frequency alternating magnetic field signal according to default, in this low frequency alternating magnetic field signal, carry the identification information of this card reader, wherein, emission parameter comprises the frequency of low frequency alternating magnetic field signal, and this frequency is equal to or less than system without the highest frequency f0 of calibration operation; The information that card reader also transmits by radio-frequency channel for receiving mobile radio device, relatively in this information, whether the identification information of card reader is consistent with the identification information of self, if consistent with self identification information and the identification information of mobile radio device be combined as combination of address, with mobile radio device by the radio-frequency channel transaction of swiping the card;
Mobile radio device, for in each range points, receive, detect the low frequency alternating magnetic field signal of card reader transmitting and be enlarged into the constant amplitude corresponding with distance voltage signal, and then judge by default voltage threshold Vt whether the terminal that is mounted with this mobile radio device has entered default coverage interval, wherein, voltage threshold Vt is identical to being mounted with all terminals of this mobile radio device; When mobile radio device is also more than or equal to default voltage threshold Vt for voltage signal corresponding to low frequency alternating magnetic field signal with receiving, from the low frequency alternating magnetic field signal receiving, obtain the identification information of card reader, and the identification information together with self sends card reader to by radio-frequency channel by it; Mobile radio device also for card reader by the radio-frequency channel transaction of swiping the card.
Wherein, identification information can be identification code ID.
From above-mentioned, card reader near field communication system of the present invention has low frequencies function and such two basic functions of radio-frequency receiving-transmitting function, also can say that the card reader near field communication system of the present invention has low frequencies module and such two basic modules of radio-frequency (RF) receiving and transmission module; Mobile radio device near field communication system of the present invention has low frequency receiving function and such two basic functions of radio-frequency receiving-transmitting function, also can say that the mobile radio device near field communication system of the present invention has low frequency receiver module and such two basic modules of radio-frequency (RF) receiving and transmission module.
Further, above-mentioned near field communication system can be realized by following physical circuit: card reader comprises at least one low frequencies coil, at least one drive circuit, at least one coding circuit, at least one first primary processor, at least one radio-frequency (RF) transmit-receive circuit and at least one radio-frequency antenna, wherein, low frequencies coil, drive circuit, coding circuit, the first primary processor, radio-frequency (RF) transmit-receive circuit, radio-frequency antenna, connection in sequential series; Mobile radio device comprises at least one low-frequency magnetic sensor circuit, at least one low-frequency amplifier circuit, at least one thresholding judgement and demodulator circuit, at least one second primary processor, at least one radio-frequency (RF) transmit-receive circuit and at least one radio-frequency antenna, wherein, low-frequency magnetic sensor circuit, low-frequency amplifier circuit, thresholding judgement and demodulator circuit, the second primary processor, radio-frequency (RF) transmit-receive circuit, radio-frequency antenna connection in sequential series.Preferably, in above-mentioned specific implementation circuit, between the drive circuit of card reader and coding circuit, can also be provided with modulation circuit.
In above-mentioned specific implementation circuit, low frequencies coil, drive circuit and coding circuit in card reader is (during band modulation circuit, also comprise modulation circuit) can think the part of low frequencies module, the first primary processor, radio-frequency (RF) transmit-receive circuit and the radio-frequency antenna in card reader can be thought the part of radio-frequency (RF) receiving and transmission module in card reader; Low-frequency magnetic sensor circuit in mobile radio device, low-frequency amplifier circuit and thresholding judgement and demodulator circuit can be thought the part of low frequency receiver module, and the second primary processor in mobile radio device, radio-frequency (RF) transmit-receive circuit, radio-frequency antenna can be thought the part of radio-frequency (RF) receiving and transmission module in mobile radio device.
Preferably, in above-mentioned specific implementation circuit, low frequencies coil can be enamel wire coil or PCB coil.Further, the number of turn of low frequencies coil can be greater than 10 circles.Preferably, the number of turn of low frequencies coil is 50～500 circles.Preferably, in low frequencies coil, filling has FERRITE CORE or iron core.Preferably, cross section the widest part of low frequencies area that coil surrounds is greater than the cross-sectional width of mobile radio terminal.Preferably, the cross section of low frequencies area that coil surrounds at least comprises the square region of border circular areas or the 3cm*3cm of diameter 3cm.
Preferably, above-mentioned low-frequency magnetic inductive circuit can be PCB coil, enamel wire coil, hall device or giant reluctivity device.
In the present invention, mobile radio device can be placed in mobile terminal, also can be placed in SIM card, UIM card, usim card, TF card or SD card in mobile terminal.Wherein, mobile terminal can be mobile phone, personal digital assistant PDA or notebook computer etc.
Below the principle of near field communication system of the present invention is described:
1, system is described in the content of aforementioned near field communication method without method for selecting and the device of the highest frequency f0 of calibration operation, repeats no more herein;
2, to realize principle as follows for range measurement and control:
Card reader is controlled target according to distance, with the continual circulation of emission parameter of setting, send not higher than the low frequency alternating magnetic field signal of selecting frequency f 0, in this signal, in the mode of modulation or directly base band transmission, carry Frame, the unique identifier Idr(that comprises card reader in Frame can certainly be other identification information).When being mounted with the mobile terminal of mobile radio device, be placed in around card reader, low frequency alternating magnetic field signal penetrates this terminal and arrives its inner mobile radio device, mobile radio device in each range points, detect this field signal and be enlarged into constant amplitude corresponding to distance voltage signal, when the amplitude of voltage lower than card in default receiver voltage threshold value Vt, represent that terminal does not enter the distance range of effectively swiping the card, do not allow to swipe the card; When the amplitude of voltage higher than card in default receiver voltage threshold value Vt, represent that terminal enters the predetermined scope of effectively swiping the card of card reader, low frequency receiving circuit in mobile radio device (referring to aforesaid low-frequency magnetic sensor circuit, low-frequency amplifier circuit and thresholding judgement and demodulator circuit) starts decode procedure, obtains the unique identification code IDr of card reader.On the other hand, there is one-to-one relationship in the voltage signal after the conversion of mobile radio device internal magnetic field and the distance between card reader and mobile radio device, this relation is determined by voltage distances change curve, according to this corresponding relation, can determine the distance between mobile radio device and card reader by this voltage, thereby indirectly determine the distance of mobile terminal and card reader.The setting of Vt and emission parameter is one action, once set in use without change.
3, the Principle of Process of mobile radio device access card reader:
Mobile radio device access card reader mainly comprises unique binding procedure of card reader and mobile radio device.Here illustrate this binding procedure: solve card reader unique identifier IDr in mobile radio device from low frequency signal after, be sent to the second main processing block in mobile radio device, this second main processing block by the unique identifier IDc of mobile radio device together with the IDr receiving, by RF transceiver module, send to card reader, card reader is received the (IDr that mobile radio device returns, IDc) after, confirming the correct identification code IDr that has returned to card reader of mobile radio device that identification code is IDc, is unique communicating terminal of this transaction.Because IDr coding has guaranteed this card reader, around the identification code of other card reader is not identical in this moment, so the identification code mobile radio device that is IDc has confirmed that the card reader that itself and identification code are IDr set up unique communication.So far, mobile radio device and card reader have realized unique binding, and both sides are by the unique identification the other side of (IDr, IDc) combination of address.Communication process after binding adopts RF passage to carry out can not producing mistake alternately.Mobile radio device completes apart from control procedure after accessing successfully, can on RF passage, carry out follow-up process of exchange, until closing the transaction.
4, process of exchange:
Card reader and mobile radio device by RF Path Setup reliable unique communication link, in this link basis, both sides can realize the process that authentication that exchange needs and other exchanges need.All these processes all complete by RF passage fast, and because completing of aforementioned process guaranteed to complete access in predetermined distance range, therefore whole process of exchange is also the Near Field Communication in limited range.
Below by embodiment, the invention will be further described.
Fig. 8 is the structure chart of near field communication system in the embodiment of the present invention.As shown in Figure 8, this system is comprised of 2 parts: card reader arrangement 100 and mobile radio device 200, and this mobile radio device 200 is placed on mobile terminal inside, and by mobile terminal communication interface and terminal interaction.
Card reader 100 is comprised of following module: the first primary processor 101, and control and other protocol processes of responsible card reader low frequency and high frequency, the first primary processor 101 is by interface circuit 102 or be directly connected to external communication interface; Coding circuit 108, be responsible for low-frequency frame data to carry out by bits of encoded, modulation circuit 107 is responsible for that the symbol stream of coding output is modulated to formation modulation signal to carrier wave and is given drive circuit 106, and the signal while not needing to modulate after coding is directly given drive circuit 106; Drive circuit 106, is responsible for driving low frequencies coil 105, produces low frequency alternating magnetic field 301; The low frequencies module being formed by low frequencies coil 105, drive circuit 106, modulation circuit 107 and coding circuit 108, its transmitting field intensity value can be changed and set; Low frequencies coil 105 consists of the coil of more number of turn given shape conventionally; RF transmission circuit 103, receives and transmitting RF signal by RF antenna 104.
Mobile radio device is comprised of following module: the second primary processor 201, and control and other protocol processes of responsible low frequency and radio-frequency module, be also responsible for the communication with mobile terminal; The SIM/TF/SD card body module that SIM/TF/SD card module 202 is mobile terminal, specifically which kind of module is determined by Card Type; Low-frequency magnetic sensor circuit 207, the circuit element being changed by PCB coil, enamel wire coil, hall device or other energy induced fields forms, and is responsible for induction low frequency alternating magnetic field signal 301 and is also converted to the signal of telecommunication; The signal of telecommunication that the responsible amplification low-frequency magnetic of low-frequency amplifier circuit 206 sensor circuit detects obtains low-frequency magnetic detectable voltage signals 303; Thresholding judgement and demodulator circuit 205, be responsible for low-frequency magnetic detectable voltage signals 303 to adjudicate according to default thresholding Vt, do not reach not demodulation of thresholding Vt and also do not allow to swipe the card, reach thresholding Vt signal is carried out to demodulation, the signal after demodulation is given the second primary processor 201; RF transmission circuit 203 is responsible for completing RF both-way communication with the RF transceiver module of card reader by RF antenna 204.
The distance that system completes without calibration by pre-set thresholding decision method detects and controls, be that card reader 100 is according to default emission parameter transmitting low frequency alternating magnetic field signal 301, mobile radio device 200 receives this field signal and is converted to low-frequency magnetic detectable voltage signals 303, and it is interval by predefined thresholding Vt, to judge whether terminal enters predefined coverage, this thresholding Vt is identical to all terminals, without revise (i.e. so-called calibration) for different terminals.By the method for low frequency one-way communication and the combination of RF both-way communication, complete unique binding of card reader 100 and mobile radio device 200, be that card reader 100 utilizes low frequency half-duplex channel that self unique ID r is passed to mobile radio device 200, mobile radio device 200 returns to card reader 100 after card self unique ID c being attached to IDr by RF bidirectional passage, card reader 100 relatively returns the correctness of IDr, and then has realized the unique binding of card reader 100 with mobile radio device 200.After binding, by radio-frequency channel, complete the communication of two-way high speed big data quantity.
In the present embodiment, the specific works flow process of near field communication system is as follows:
(1) first, the basic parameter of selecting system work, comprises RF frequency, without calibration low frequency frequency f0, card reader emission parameter, the receiver voltage thresholding Vt of mobile radio device.
1.RF frequency is selected
The frequency of above-mentioned RF communication adopts 2400～2483MH2.4G ISM band conventionally, to realize communication and the good penetration to terminal at a high speed, also can adopt other frequency, 433MHz for example, 900MHz, 5GHz etc.
2. without calibration low frequency frequency f0, select
Adopt preceding method to determine that system low frequency is without calibration operation frequency f0, for typical GSM communication terminal, realize the distance of 0～10cm scope and control, f0 frequency is less than 10KHz conventionally, representative value comprises 500Hz, 1KHz, 1.5KHz, 2KHz, 2.5KHz, 3KHz, 5KHz etc.
3. the selection of card reader emission parameter
Emission parameter mainly comprises modulation system, coded system and transmitting magnetic flux density amplitude Br.
Fig. 9 is card reader low frequencies part schematic diagram.Referring to Fig. 8, card reader low frequencies circuit consists of drive circuit 106, modulation circuit 107 and coding circuit 108, and the low-frequency modulation signal that drive circuit 106 drives outputs to low frequencies coil 105.
Modulation circuit 107 can adopt Different Modulations:
1) carrier modulation mode is modulated: the baseband signal that coding circuit 108 produces is modulated by 107 pairs of carrier waves of modulation circuit, carrier wave can be sine wave, square wave and triangular wave etc., modulation can adopt switch frequency shift keying OOK, phase shift keying, frequency shift keying fsk etc., and the signal after modulation is loaded on low frequencies coil 105 by drive circuit 106;
2) the direct baseband transmission of carrierfree: the baseband signal that coding circuit 108 produces, is directly loaded on low frequencies coil 105 by drive circuit 106;
3) other modulation systems: control because system of the present invention adopts the mode of thresholding judgement to carry out distance, therefore modulation system should not adopt amplitude modulation(PAM), and in every process of transmitting, can keep detecting the substantially invariable modulation system of voltage amplitude in mobile radio device all can be near field communication system of the present invention;
Coding circuit 108 can adopt Multi-encoding mode:
1) Manchester's code: bit 1 is encoded to two symbols 01, and bit 0 is encoded to 10.
2) Differential Manchester Encoding: have two kinds of bit symbol sequences: 01 and 10, it is different from a upper symbol sebolic addressing that bit 1 is encoded to, and 0 of bit is identical, or coding also can conversely.
3) other coded systems: control because system of the present invention adopts the mode of thresholding judgement to carry out distance, therefore low-frequency modulation signal must keep equal value stabilization, sequence after coding can not contain DC component, and every coding afterwards average DC component is that zero coded system all can be near field communication system of the present invention.
Determine after modulation system and coded system, adopt preceding method, determine card reader transmitting magnetic flux density amplitude Br.The process of adjusting Br is actually adjustment coil turn, wire diameter, the isoparametric process of shape.
4. the selection of mobile radio device receiver voltage thresholding Vt
Adopt preceding method to determine clamping receipts threshold voltage Vt.
The selected of above-mentioned parameter is disposable, once selected, in work without change.
(2) secondly, the working-flow after running parameter is determined is as follows:
Steps A 100: range measurement and control procedure.The first primary processor 101 of card reader 100 produces the Frame of the unique identifier IDr that comprises card reader, give coding circuit 108 and complete coding, signal after coding is modulated by modulation circuit 107 or is directly given drive circuit 106 without modulation, modulation voltage gives low frequencies coil 105 transmittings, by pre-set frame format, modulation coding mode and driving force, the intensity Br continual low frequency alternating magnetic field signal 301 that according to above-mentioned frame format circulation send designated parameter of transmitting coil 105 to set.Around mobile terminal is placed in card reader, low-frequency alternating magnetic field signal 301 penetrates this terminal and arrives inner mobile radio device 200, low-frequency magnetic sensor circuit 207 in mobile radio device 200 detects low-frequency magnetic signal, be converted to after the signal of telecommunication amplifies by low-frequency amplifier circuit 206 and obtain low-frequency magnetic detection voltage 303, when the amplitude of voltage is less than (or being greater than) in default receiver voltage threshold value Vt, do not allow to swipe the card; When the amplitude of voltage is more than or equal in (or being less than or equal to) default receiver voltage threshold value Vt, represent that terminal enters the predetermined scope of effectively swiping the card of card reader, low frequency receiving circuit starts decode procedure, obtains the unique identification code IDr of card reader.On the other hand, there is one-to-one relationship in the voltage signal after described mobile radio device internal magnetic field conversion and the distance between card reader and mobile radio device, this relation is determined by voltage-variable in distance curve, according to this corresponding relation, can be determined by this voltage the distance of mobile radio device and card reader, thereby indirectly determine the distance of mobile terminal and card reader.Above-mentioned threshold value Vt is all identical to all terminals, and without for each end correction, namely without knowing calibration, thereby said process is a kind of range measurement and control procedure without calibration;
Frame format in steps A 100 is defined as follows:
Figure 10 is card reader low-frequency data frame format schematic diagram, and as shown in figure 10, the every frame of card reader low-frequency data frame is divided into following territory:
Synchronous code: 8 bits, are generally FFH, for frame synchronization;
Control domain: 8 bits, for the solution frame information of frame data is provided, as length, data type etc., can stay and retain position for expansion;
IDr:N bit, card reader unique identifier, is specified by control domain;
CRC: to control domain, IDr carries out verification, can adopt CRC check and or other modes.
Above described frame format only as a kind of example, do not limit the frame format of the actual employing of the present invention, in principle any comprise can unique identification card reader frame format all can use.Unique identifier can adopt the random number of sufficient length, also can adopt the mode of all card reader manual allocation unique codes, or the identification code that produces of other modes.
Steps A 200: the process of mobile radio device access card reader: mobile radio device access card reader mainly comprises unique binding procedure of card reader 100 and mobile radio device 200, in fact represents unique binding procedure of card reader and mobile radio device place mobile terminal.The inner low frequency receiving circuit of mobile radio device 200 is sent to the first primary processor 201 in mobile radio device after solving card reader unique identifier Idr, this module by the unique identifier Idc of mobile radio device self together with the Idr receiving, by RF transmission circuit 203 in mobile radio device and RF antenna 204, send to card reader 100, card reader internal RF antenna 103 and RF transmission circuit 104 are received the (IDr that mobile radio device returns, IDc) after, sending the first primary processor 101 to processes, the first primary processor 101 confirm mobile radio device that identification codes are IDc correct returned to card reader IDr, it is unique communicating terminal of this transaction.Because IDr coding has guaranteed this card reader, around the identification code of other card reader is not identical in this moment, so the identification code card that is IDc has confirmed that the card reader that itself and identification code are IDr set up unique communication.So far, mobile radio device and card reader have realized unique binding, and both sides are by the unique identification the other side of (IDr, IDc) combination of address.Communication process after binding adopts RF passage to carry out can not producing mistake alternately.Mobile radio device successfully accesses after card reader, apart from control procedure, completes, and can on RF passage, carry out follow-up process of exchange;
Mobile radio device unique identifier IDc in steps A 200, be pre-stored in mobile radio device inner nonvolatile memory the unique identifier of (NVM), or by the sufficiently long random number producing in mobile radio device.
Steps A 300: process of exchange.Card reader 100 and mobile radio device 200 by RF Path Setup reliable unique communication link, in this link basis, both sides can realize the process that authentication that exchange needs and other exchanges need.All these processes all complete by RF passage fast, until this closing the transaction.Because completing of abovementioned steps A100～A200 guaranteed mobile radio device 200, can only in predetermined distance range, complete access, therefore whole process of exchange is also just can complete transaction in limiting distance range.Process of exchange is ripe POS machine handling process, and the present invention is not described in detail.
Mobile radio device 200 medium and low frequency signal deteching circuits 207 can use PCB coil, enamel wire coil or hall device to form conventionally, this testing circuit is not limited in these several elements, any transducer that changes of magnetic field can be changed into the signal of telecommunication may be used to this module in principle, and unique restriction is to put into card inside.
System of the present invention is utilized low frequency alternating magnetic field to realize distance and is detected and control, and realize the one-way communication of card reader and mobile radio device, utilize RF passage in conjunction with low frequency communication, to realize the reliable binding of terminal, utilize RF passage to realize the data communication of high speed between card reader and mobile radio device simultaneously.It has following features point: 1. can only need to change SIM card/TF/SD card of terminal inner without transformation mobile terminal, can realize reliable two-way range communication; 2 card reader transmitting low frequency alternating magnetic field signals, mobile radio device only need receive this field signal, owing to being one-way communication, and by magnetic field, provide energy without card reader, therefore can, by receiving coil or other receiving circuit miniaturizations, be enough to mobile radio device to put into SIM card/TF/SD card; Due to receive signal a little less than, in mobile radio device, need to increase amplifying circuit.In mobile radio device, place RF transmission circuit in addition simultaneously, realize bidirectional high speed communication with the RF transmission circuit in card reader, as previously described, the antenna of RF circuit is very little, can be integrated into easily in SIM card/TF/SD card.
According to the selected frequency f0 of the method for the invention, system is worked below frequency without calibration at this, as a kind of expansion, system works, neither be not on your life more than f0 frequency, and possible effect is that performance reduces, the precision that distance is controlled reduces, may need to be aided with simple calibration, these application fundamentally do not conflict with principle of the present invention simultaneously, are a kind of extension application of performance change.
Near field communication system of the present invention has realized the radio communication terminal that the contains mobile radio device mobile phone of radio-frequency SIM card (as be equipped with) and has been controlled in prescribed limit reliably with the data communication distance (also i.e. transaction distance) of card reader, and without terminal is calibrated.
Adopt system and method for the present invention, select the suitable high frequency points f0 without calibration operation, use the low frequency alternating magnetic field lower than f0 to carry out range measurement and control, within between mobile terminal, the impact of architectural difference can be reduced to the desired fluctuation range of distance control target, thereby realize, without calibrated distance, control.Figure 11 is that coil receiving circuit is put into various mobile terminals, launches the voltage distances curve of testing under constant 1KHz magnetic field condition by signal source by low frequencies coil.As shown in figure 11, be the voltage distances curve example of system a plurality of exemplary terminal under 1KHz frequency.Wherein signal strength values is the value of reception antenna induced voltage after necessary amplification, and it is constant that multiplication factor keeps, and only needs to pay close attention to the relative variation of intensity distance.As can be seen from Figure 11, field intensity difference <5dB between terminal, and each terminal reaches 40dB in the field intensity excursion of 1～10cm scope, do not consider the error of card reader transmitting field strength fluctuation and mobile radio device testing circuit, mobile radio device end adopts unified thresholding Vt to judge that each terminal is whether within target range scope, the difference of the error that distance is controlled between terminal is roughly 1cm scope, meets the requirement of controlling without calibrated distance completely.
RF IC card, radio frequency storage card
A side as short-range communication, mobile radio device is normally placed in IC-card (such as SIM card, UIM card, usim card etc.) in mobile terminal or storage card (for example TF card, SD card, MMC(Multi Media Card, multimedia card) card etc.) in, we are called RF IC card and radio frequency storage card by the IC-card and the storage card that are equipped with mobile radio device.
Figure 12 is the structure chart of RF IC card in the embodiment of the present invention.As shown in figure 12, in the present embodiment, RF IC card 1200 is comprised of mobile radio device and SIM/UIM/USIM card module (can be referred to as IC-card module) 1202 and interface module 1207.In Figure 12, mobile radio device comprises at least one low-frequency magnetic sensor circuit 1206, at least one low-frequency amplifier circuit 1215, at least one comparison circuit 1225, at least one demodulator circuit 1235, at least one decoding circuit 1245, at least one second primary processor 1201, at least one RF(radio frequency) transmission circuit 1203 and at least one RF(radio frequency) antenna 1204, wherein low-frequency magnetic sensor circuit 1206, low-frequency amplifier circuit 1215, comparison circuit 1225, demodulator circuit 1235, decoding circuit 1245, the second primary processor 1201, RF transmission circuit 1203, RF antenna 1204 connection in sequential series.Wherein, comparison circuit 1225, demodulator circuit 1235 and decoding circuit 1245 have formed thresholding judgement and the demodulator circuit of mobile radio device.In other embodiments of the invention, in the judgement of the thresholding of mobile radio device and demodulator circuit, also can not comprise demodulator circuit 1235, and only by comparison circuit 1225 and decoding circuit 1245, be formed.In Figure 12, low-frequency amplifier circuit 1215, comparison circuit 1225, demodulator circuit 1235 and decoding circuit 1245 form low frequency signal and receive and processing module 1205.Wherein, the second primary processor 1201 is identical with the second primary processor in aforesaid mobile radio device.Wherein, the low frequency receiver that low-frequency magnetic sensor circuit 1206, low-frequency amplifier circuit 1215, thresholding judgement and demodulator circuit (comprising comparison circuit 1225, demodulator circuit 1235 and decoding circuit 1245) form works in previously selected system without the frequency below the highest frequency f0 of calibration operation.System is described before definite method of the highest frequency f0 of calibration operation, repeats no more herein.Low frequency receiver is converted to the low frequency alternating magnetic field of constant amplitude or differential constant amplitude the detection voltage of constant amplitude through magnetoelectricity, the error of this amplitude is δ c dB.
By selecting the multiplication factor of different low-frequency magnetic sensor circuits and low-frequency amplifier circuit can select the volume of different low frequency receivers, thereby mobile radio device can select to put into the carrier of different volumes requirement.If low-frequency magnetic sensor circuit is coil, the volume of low frequency receiver depends on the multiplication factor of low-frequency magnetic sensor circuit conversion gain and low-frequency amplifier circuit.Magnetoelectricity conversion gain conversion formula is: K*A=Vt/B_RATEgate, wherein B_RATEgate is the threshold value of magnetic flux density rate of change, magnetic flux density rate of change B_RATE=dBr/dt, the multiplication factor that A is low-frequency amplifier circuit, K is low-frequency magnetic sensor circuit conversion gain; Low-frequency magnetic sensor circuit conversion gain is to swipe the card farthest apart from corresponding systemic presupposition value with the applied system of mobile terminal with the product of the multiplication factor of low-frequency amplifier circuit, the distance of swiping the card is farthest B_RATEgate at this distance card reader transmitting field intensity parameter value, the voltage of the inner detection of mobile device is simultaneously just threshold value Vt, now allow to swipe the card, surpass this range transmission field intensity continuous decrement and be less than B_RATEgate, the inner voltage that detects of mobile device is less than Vt, does not allow to swipe the card.In above-mentioned relation formula, Vt and B_RATEgate are the values of being determined by system, therefore K*A value is determined, the volume of coil is mainly determined by K value, coil turn is more, K is larger, volume is larger, and the size of A value is on the volume of low-frequency amplifier circuit substantially without impact, so the distribution of magnetoelectricity conversion overall gain between K and A will determine the volume of low frequency receiver.For example, if mobile radio device is placed in SIM card, select coil turn easily to place and enter the winding volume in card at 1～20 circle range content, therefore first determined magnetic conduction circuitry conversion gain, then selected the gain that low-frequency amplifier circuit is larger.If mobile radio device is placed on terminal mainboard, this can increase coil turn and area, and amplifier gain can reduce, and benefit is that signal to noise ratio has lifting, and harm is that low frequency receiver volume becomes greatly.When low-frequency magnetic sensor circuit is coil, in the situation that the magnetoelectricity conversion gain A*K of low frequency receiver is preset value, the gain that changes A and K distributes, the signal to noise ratio that can change volume and the reception signal of low frequency receiver, increases K, reduces A, volume increases, and signal to noise ratio increases; Reduce K, increase A, volume reduces, and signal to noise ratio reduces.
If magnetic conduction circuitry is hall device or giant reluctivity device, the multiplication factor relation of the volume of low frequency receiver and described low-frequency magnetic sensor circuit conversion gain and low-frequency amplifier circuit is little.
In Figure 12, the second primary processor 1201, SIM/UIM/USIM card module 1202, RF transceiver module 1203, low frequency signal receive and processing module 1205, interface module 1207 can be by being integrated into an IC(integrated circuit) inner circuit and peripheral passive device form, also can combination in any enter behind different IC inside, add that peripheral passive device forms.
Wherein, RF antenna 1204, can not be integrated into IC inside, can use PCB antenna, the copper sheet printed wiring of PCB, consists of.
Low-frequency magnetic sensor circuit 1206 is for receiving low frequency magnetic field signal, gives low-frequency amplifier circuit 1215 below after low frequency magnetic field signal is transformed to corresponding voltage signal.Low-frequency magnetic sensor circuit 1206 can be by realizations such as PCB coil, enamel wire coil, hall device, giant reluctivity devices.Generally, between low-frequency magnetic sensor circuit 1206 signals 1302 of output and the low frequency magnetic field signal strength signal 1301 of its environment of living in or low frequency magnetic field signal strength signal rate of change 1301, be fixing linear ratio relation, be 1302=1301*K, wherein K is constant, and K depends on the characterisitic parameter of low-frequency magnetic sensor circuit 1206.The signal 1302 of low-frequency magnetic sensor circuit 1206 outputs can be voltage signal, can be also other signals such as electric current, and generally signal 1302 is voltage signals.If low-frequency magnetic sensor circuit 1206 is used hall device or giant reluctivity device to form, voltage signal 1302 is directly proportional to low frequency magnetic field signal strength signal intensity 1301.If low-frequency magnetic sensor circuit 1206 is used PCB coil or enamel wire coil to form, voltage signal 1302 is directly proportional to low frequency magnetic field signal strength signal rate of change 1301.Typical antenna be the ring-type differential constant amplitude induction antenna along the outmost turns N circle pcb copper sheet composition of card, output be voltage signal 1302.For example, be applied to SIM card 4 circle pcb copper sheet coil antennas a kind of structure as shown in figure 13.
The second primary processor 1201 is realized the coordination of whole RF IC card 1200 and is controlled processing, and various control hardwares, program module and memory are contained in the second primary processor 1201 the insides.The second primary processor 1201 is realized by IC and peripheral passive component, and major function is realized by IC, and peripheral cell only helps out.
SIM/UIM/USIM card module 1202 is connected with the second primary processor 1201, and between the second primary processor 1201, has the mutual of application data.SIM/UIM/USIM card module 1202 is mainly realized by IC.The second primary processor can with SIM/UIM/USIM/TF/SD/MMC card in processor be same common processor.With a shared processor, do the work that the processor in the second processor and SIM/UIM/USIM/TF/SD/MMC card will be done simultaneously.
Interface module 1207 is connected with the second primary processor 1201, and the second primary processor 1201 is connected with the communication interface of mobile terminal by interface module 1207, and carries out data interaction with mobile terminal.Interface module 1207 is realized by IC, and generally the second primary processor 1201 and interface module 1207 are integrated in same a slice IC inside.SIM/UIM/USIM card module 1202 can carry out data interaction with mobile terminal by the second primary processor 1201 and interface module 1207, completes due function.
Low frequency signal receives and processing module 1205 is connected with the second primary processor 1201, is also connected with low-frequency magnetic sensor circuit 1206.Low frequency signal receives and processing module 1205 receives the low frequency magnetic field signal 1302 sending from low-frequency magnetic sensor circuit 1206, low frequency magnetic field signal 1302 is amplified to A and obtain signal 1303 after doubly, be i.e. signal 1303=A* signal 302.Low frequency signal receives and whether processing module 1205 comparison signals 1303 are greater than the thresholding Vt of setting, and comparative result is sent to the second primary processor 1201.Low frequency signal receives and processing module 1205 also decodes out by data message in signal 1303, gives the second primary processor 1201.Low frequency signal reception and processing module 1205 are accepted the control of the second primary processors 1201, receive the control informations such as thresholding Vt that the second primary processor 1201 is brought.
RF transmission circuit 1203 is connected with the second primary processor 1201.RF transmission circuit 1203 is connected with RF antenna 1204, by the aerial radiofrequency signal 400 of RF antenna 1204 transmitting-receiving.RF transceiver module 1203 under the control of the second primary processor 1201, completes the rf data communication with card reader together with RF antenna 1204.
Low-frequency magnetic sensor circuit 1206 receives with low frequency signal and processing module 1205 is connected, and receives the low frequency magnetic field signal 1301 of aerial card reader transmitting, is transformed to low frequency magnetic field signal 1302, gives low frequency signal reception and processing module 1205 and processes.
Low frequency signal receives and processing module 1205 is comprised of low-frequency amplifier circuit 1215, comparison circuit 1225, decoding circuit 1245 and optional demodulator circuit 1235.Demodulator circuit 1235 is optional, while not carrying out modulation /demodulation when the digital signal of low frequency magnetic field transmission is only carried out to baseband coding, does not need to use demodulator circuit 1235, otherwise need to use demodulator circuit 1235.
Low-frequency amplifier circuit 1215 receives the low frequency magnetic field signal 1302 that low-frequency magnetic sensor circuits 1206 are sent here, low frequency magnetic field signal 1302 is amplified to A and obtain signal 1303 after doubly.Signal 1303 is given comparison circuit 1225 and is processed.Signal 1303 is also given demodulator circuit 1235 and is processed, if there is no demodulator circuit 1235, signal 1303 is directly given decoding circuit 1245 and processed.Allow the transduction factor K of the magnetic flux density thresholding Bgate that swipes the card or magnetic flux density rate of change thresholding B_RATEgate, low-frequency magnetic sensor circuit 1206, the multiplication factor A of low-frequency amplifier circuit 1215, between the threshold voltage signal Vt arranging, must meet following relationship, i.e. Bgate*K*A=Vt or B_RATEgate*K*A=Vt.Wherein, the multiplication factor A of low-frequency amplifier circuit 1215 can arrange by software.
Comparison circuit 1225 is connected with the second primary processor 1201, the signal 1303 that reception is brought from low-frequency amplifier circuit 1215, whether comparison signal 1303 surpasses thresholding Vt, if signal 1303 relatively changes with thresholding Vt, just the information of situation of change is sent to the second primary processor 1201.Thresholding Vt is arranged by the second primary processor 1201, and is stored in comparison circuit 1225.When comparison circuit 1225 compares signal 1303 with Vt, Vt value also can arrange by software.
Demodulator circuit 1235 is connected with decoding circuit 1245, receives the signal 1303 of sending here from low-frequency amplifier circuit 1215, and the baseband signal after demodulation is given decoding circuit 1245.
Decoding circuit 1245 is connected with the second primary processor 1201, receives the baseband signal that low-frequency amplifier circuit 1215 or demodulator circuit 1235 are sent here, obtains the information that card reader sends over by low frequency magnetic field after decoding, gives the second primary processor 1201.Decoding circuit 1245 can be realized by the technology of difference manchester decoder.
Radio frequency storage card is comprised of mobile radio device and TF/SD/MMC card module (can be referred to as memory card module) and interface module.In Figure 12, only the SIM/UIM/USIM card module 1202 of RF IC card need be replaced by TF/SD/MMC card module can obtain radio frequency storage card.Other parts of radio frequency storage card are consistent with RF IC card, radio frequency storage card repeated no more herein.Figure 16 is the 4 circle pcb coil antenna structure schematic diagrames that are applied to TF card.
Utilize above-mentioned RF IC card/radio frequency storage card, can realize function below:
1, low frequency magnetic field one-way data communication function
RF IC card/radio frequency storage card of the present invention, can receive the data message in low frequency magnetic field.The code modulation mode of data message can be used existing various mature technology.For example can use different manchester encoding technology, use low frequency magnetic field rate of change directly to transmit the different manchester encoding baseband signal after coding.
The cycle of each set time length is transmitted a data bit(bit), in the middle moment during the transmission of a bit, level must change, but two boundary moment that different bit transmit, level can change, and also can not change.So the middle code word constantly during a bit transmits only has two: 01,10.Send bit 1, adopt and a upper code word that code word is different.Send bit 0, adopt and a upper code word that code word is identical.Figure 14 is the different manchester encoding form of 5bit data 11010 and field intensity, coil receiver voltage oscillogram.In Figure 14, be the different manchester encoding format chart of 5bit data 11010, b is the field strength pattern that a is corresponding, and c is the corresponding voltage oscillogram that coil receives.As seen from Figure 14, in different manchester encoding, difference represents 1, identically represents 0.
2, the low frequency alternating magnetic field of constant amplitude or differential constant amplitude is converted to the detection voltage of constant amplitude through magnetoelectricity, and carries out thresholding comparing function and control function of swiping card
Constant amplitude low frequency alternating magnetic field is the low frequency alternating magnetic field that magnetic flux density amplitude of variation is constant, for example square wave and sine wave.
Differential constant amplitude low frequency alternating magnetic field refers to the constant low frequency alternating magnetic field of amplitude of variation of the rate of change of magnetic flux density, and for example triangle involves sine wave.
Constant amplitude (or differential constant amplitude) signal 1301 is transformed to low frequency magnetic field voltage signal 1302 through low-frequency magnetic sensor circuit piece 1206, and establishing 1301 magnetic flux density is Br, and magnetic conduction circuitry receiving sensitivity is K; Voltage signal 1302=K*Br or K*dBr/dt.
Low-frequency amplifier circuit 1215 amplifies A doubly by voltage signal 1302, obtains voltage signal 1303: voltage signal 1303=A* voltage signal 1302.
So, voltage signal 1303=K*A*Br or K*A*dBr/dt.
As long as record voltage signal 1303, just can be scaled corresponding constant amplitude (or differential constant amplitude) signal 1301.
Whether comparison circuit 1225 comparative voltage signals 1303 are greater than Vt, and give the second primary processor 1201 by comparative result information.The second primary processor 1201 determines whether to allow to swipe the card according to comparative result information.
And the low frequency receiver of mobile radio device is measured field intensity and had error, this error equals the error of RF IC card/radio frequency storage card substantially, source of error in following a)～e) 5 aspects:
A) the error ratio eK (db) of transducer (low-frequency magnetic sensor circuit) conversion coefficient K;
B) the error ratio eA (db) of amplifier (low-frequency amplifier circuit) multiplication factor A;
C) comparator (comparison circuit) error ratio eO (db);
D) amplifier (low-frequency amplifier circuit) allows equivalent input noise coefficient eN (db);
E) other error e C (db);
These 5 errors have all comprised due to temperature, the error that the Working Environments such as voltage cause.
The system consisting of the mobile terminal of card reader and built-in mobile radio device is in order to reach the target of controlling without calibrated distance, links to the fluctuation of detection voltage in system distributes, and is assigned to the admissible fluctuation of mobile radio device itself and is called the low frequency detection scope range of the fluctuation of voltage δ c (db) that mobile radio device causes.The summation of the error factor of above-mentioned five mobile radio device RF IC card/radio frequency storage cards must be less than system assignment to the error criterion δ c (db) of card.That is:
eK(db)+eA(db)+eO(db)+eN(db)+eC(db)<δc(db)
Low-frequency amplifier circuit 1215 is integrated in card chip internal, generally the working power voltage of chip internal is the order of magnitude of 1 volt, so, take constant amplitude testing circuit as example, corresponding Vt should be at the order of magnitude of 1 volt, so, Bgate*K*A should be about 1V, requires like this K*A=Vt/Bgate=1 volt/Bgate.And the multiplication factor A of low-frequency amplifier circuit, during by chip design, design is determined, can there is in theory very large scope freely to select, once but Bgate determines and transducer determines that K is also with regard to after determining, the size of A has also just been determined, A=Vt/Bgate/K, generally Vt can get 1V, and A can value be 1V/Bgate/K.So, the size of A, is determined by other parameters, but the span of K just can allow a wider scope, and consequently the selection of low-frequency magnetic sensor circuit 1206 has just had very large flexibility.
Because the selection of low-frequency magnetic sensor circuit 1206 can have the larger degree of freedom, therefore can be chosen in the 4 circle pcb coils that are easy in engineering to realize as low-frequency magnetic sensor circuit 1206 on card, see Figure 13.Can certainly select the transducer of other parameters.Use 4 circle pcb coil pickoffs to have following advantage: 1, to be easy to realize, not increase the structure on card, on card, originally just needed pcb; 2, do not increase the volume of card.Thereby the antenna of this scheme can be realized on card, do not need to be connected on card antenna in addition.
The distribution design of the error surplus δ c (db) of RF IC card/radio frequency storage card is also an important content of card.Use the design of this programme, error surplus δ c (db) need to be assigned in following 5 factors:
A) the error ratio eK (db) of transducer (low-frequency magnetic sensor circuit) conversion coefficient K;
B) the error ratio eA (db) of amplifier (low-frequency amplifier circuit) multiplication factor A;
C) comparator (comparison circuit) error ratio eO (db);
D) amplifier (low-frequency amplifier circuit) allows equivalent input noise coefficient eN (db);
E) other error e C (db).
Such as, if allow farthest to swipe the card, distance B max requires as 10cm, the distance B min that must swipe the card is recently 5cm, so as can be seen from Figure 15 the peak signal of 10cm is 12db, the weak signal of 5cm is 28db, so total error surplus has 28-12=16db, wherein only distributes the error surplus of 4db to card, so δ c (db)=4db.EK (db), eA (db), eO (db), eO (db), eC (db) mean allocation, each has 0.8db.And low-frequency magnetic sensor circuit 1206 is used the words of 4 circle pcb coils, because PCB production technology is very ripe, its scale error is in 0.1mm, and its K value error depends mainly on the area error of coil, the percentage error that can calculate K is about 0.1mm*0.1mm/25mm/15mm, general is 2.67*10-5, and being scaled db number is 20log(1+2.67*10-5)=0.0023db.Its numerical value is far smaller than 0.8db.The error ratio eA of low-frequency amplifier circuit multiplication factor A is decided by the resistance ratio in integrated circuit technology, the error of its ratio, under existing process conditions, is easy to just can accomplish below 1%, being scaled db number should be 20log(1+0.01)=0.086db, be also far smaller than 0.8db.Comparison circuit error and other errors are no longer analyzed.Above error distribution and analytic explanation, used this programme can be easy to realize the target that distance is controlled.
In order to reach, do not change mobile terminal, only need to change the SIM/UIM/USIM/SD/TF/MMC card in mobile terminal, realize paying by mails and wait the transaction of swiping the card, the present invention proposes a kind of low frequency alternating magnetic field apart from control method, be applied to the various mobile terminals that comprise above-mentioned mobile radio device, comprise the steps:
Prerequisite: mobile device works in previously selected system without the frequency below calibration operation frequency f0.
Step a, carries out magnetoelectricity conversion to the low frequency alternating magnetic field signal Br receiving, and low frequency alternating magnetic field signal is converted to signal of telecommunication Vo.If the low frequency magnetic field signal that Br is constant amplitude, magnetoelectricity conversion formula is Vo=A*K*Br; If Br is the low frequency magnetic field signal of differential constant amplitude, magnetoelectricity conversion formula is Vo=A*K*dBr/dt, and wherein K is magnetic conduction circuitry gain, the gain of A low-frequency amplifier circuit, A*K is magnetoelectricity conversion gain, this gain presets, in use without change; There is error in magnetoelectricity conversion, namely Vo exists fluctuation, and fluctuation range is δ c (db);
Step b, if the signal of telecommunication Vo of low-frequency magnetic induced magnetism signal conversion is greater than default comparative voltage signalc threshold Vt, decode the identification sign IDr of card reader, enter radio-frequency communication, by radio-frequency channel, together with the unique identifier IDc of mobile device itself, together send IDr to card reader, continue monitoring low-frequency magnetic induced signal simultaneously;
Step c, carrying out radio-frequency communication, is a plurality of packet gradation transmitting-receivings by radio-frequency communication Data Division, if each radio frequency packet receiving or give out a contract for a project and all check whether Vo is greater than Vt and continues radio-frequency communication until closing the transaction, otherwise finish the radio-frequency communication of this transaction, return to step a.
In step a, definite method of magnetoelectricity conversion gain is as follows:
Step a1, determines magnetic induction gain K.On the carrier of selected mobile radio device place, be easy to the magnetic conduction circuitry of Project Realization, as coil, hall device and giant reluctivity device, thus selected magnetic induction gain K;
Step a2, the gain A of arbitrarily selected low-frequency amplifier circuit under following principle
1) the magnetic induction density B r that mobile device locates to receive is at an arbitrary position less than the value of system safety code requirement;
2) mobile device is positioned in one or more carriers (such as mobile terminal) of system appointment, and in the distance of system requirements, control target farthest can receiving range place, the Signal-to-Noise of magnetic induction signal after magnetoelectricity conversion is greater than SNR.Common SNR>5;
3), if low-frequency magnetic sensor circuit is hall device or giant reluctivity device, for detection of the low frequency alternating magnetic field signal of constant amplitude: A*K=Vt/Bgate, wherein Bgate is magnetic flux density thresholding; If magnetic conduction circuitry is coil, for detection of the low frequency alternating magnetic field signal of differential constant amplitude: A*K=Vt/B_RATEgate, wherein B_RATEgate is the threshold value of magnetic flux density rate of change, magnetic flux density rate of change B_RATE=dBr/dt.
If low-frequency magnetic sensor circuit is coil, mobile radio device is placed in SIM, UIM card, usim card, TF card, SD card or mmc card, and the number of turn of coil can be 1～20 circle, and amplifier gain A is greater than 100; If low-frequency magnetic sensor circuit is coil, mobile device is placed in mobile terminal, is meeting under the condition of above-mentioned magnetoelectricity conversion gain system of selection, and coil turn is unrestricted, and the gain A of low-frequency amplifier circuit is unrestricted.
In step a, selection and the control method of the fluctuation range δ c of mobile radio device detection voltage are as follows:
The system of selection of δ c is as follows: δ c is that the system that forms of the mobile terminal by card reader and built-in mobile radio device is in order to reach the target of controlling without calibrated distance, links to the fluctuation of detection voltage in system distributes, and is assigned to the admissible fluctuation of mobile radio device itself and is called the low frequency detection scope range of the fluctuation of voltage δ c (db) that mobile radio device causes.Because the working frequency points of low frequency receiver is very low, cause the factor that detects voltage fluctuation: low-frequency magnetic sensor circuit gain error, low frequency amplifier multiplication factor error, comparison circuit error, circuit noise, the impact such as the error that circuit temperature coefficient causes is very little, and therefore the fluctuation range of card is confirmable smaller, for example 2～6dB.
The control method of δ c is as follows: for solving the difference problem that detects field intensity between a plurality of mobile radio devices, the present invention proposes based on the error control method of error control system as shown in figure 17, be applied to above-mentioned mobile radio device.In Figure 17, the transmitting coil 504 in standard card reader 505 is to the mobile radio device 501 in fixed range and the standard barrier 502 transmitting constant amplitude that are in a fixed position or the low frequency magnetic field signal of differential constant amplitude.Mobile radio device 501 is by being connected with PC with the device 503 of cartoon news.The control method of δ c comprises the steps:
Suppose that the applied various mobile terminals of mobile device are δ T to the maximum fluctuation scope of the decay of low frequency alternating magnetic field signal, error control system Plays barrier decay to δ T/2, the effect of this barrier is that to make the decay of the low frequency alternating magnetic field that mobile radio device receives be the median of various terminals decay.
Step 601: as Figure 17, standard card reader is launched the low frequency alternating magnetic field signal of constant amplitude or differential constant amplitude on fixed range and position, and under this system, the magnitude of voltage of the magnetic field of range value Bgate or differential range value B_RATEgate after magnetoelectricity is changed should be amplitude near voltage signal Vo Vt;
Step 602: determine a rational Vo value range=(Vt-δ cx/2, Vt-δ cx/2), wherein δ cx< δ c, this is because δ c comprises multiple fluctuating factor, for simplification error control system and method, some factors can not be measured completely, such as temperature error etc.;
Step 603: measure the output electrical signals Vo of mobile radio device medium and low frequency amplifying circuit, if Vo exceeds (Vt-δ cx/2, Vt-δ cx/2) scope, by software, the multiplication factor A that adjusts low-frequency amplifier circuit is set, until Vo is in above-mentioned scope;
Step 604: the Vt value that mobile radio device is set by software is that step 603 is adjusted the output electrical signals Vo after A.
Application the present invention can realize the mobile terminal payment without calibration, illustrates the Method and Process of realizing without the mobile terminal payment of calibration below in conjunction with example.
Implementation procedure has following precondition:
Precondition 1: the low frequency magnetic field signal strength signal intensity of supporting card reader transmitting is adjusted, and its field intensity spatial distribution has met the requirement that distance is controlled;
Further, the field signal of differential constant amplitude, the magnetic flux density rate of change that allows the field intensity thresholding Bgate that swipes the card is ± 26500A/m/s (the every metre per second (m/s) of 26500 peace), if the field signal of 2KHz, the peak value of magnetic flux density is ± 3.32A/m that its peak-to-peak value magnetic flux density is 6.64A/m, if the field signal of 1KHz, the peak value of magnetic flux density is ± 6.64A/m that its peak-to-peak value magnetic flux density is 13.28A/m;
Precondition 2: RF IC card/radio frequency storage card, before dispatching from the factory, is provided with suitable threshold voltage Vt, the operating distance of swiping the card that this threshold voltage Vt limits corresponding to needs;
Further, threshold voltage Vt is corresponding to the magnetic flux density rate of change of the field intensity thresholding Bgate that allows to swipe the card during for ± 26500A/m/s, and the peak-to-peak value voltage Vt after the output voltage 1302 of low-frequency magnetic sensor circuit amplifies is 1V; Magnetic flux density rate of change is ± during 26500A/m/s, the output voltage peak-to-peak value of low-frequency magnetic sensor circuit is 100uV, multiplication factor A=Vt/100uV=1V/100uV=10000;
Precondition 3: the communication between RF IC card/radio frequency storage card and card reader and the agreement of swiping the card provide;
Further, the data bit flow between RF IC card/radio frequency storage card and card reader can be used the different manchester encoding baseband signal of 2K baud rate to carry out data transmission.Data message be take Frame and is transmitted as unit, and the coded system of Frame bit stream is as follows: every frame data have the synchronous head of 9bit, and synchronous head is 8bit 1, after one 0.In synchronous head data message below, continuous 71 are added one 0 below, for distinguishing data message and synchronous head;
Precondition 4: RF IC card/radio frequency storage card is installed in mobile terminal, and be ready to the operation of swiping the card;
Precondition 5: card reader is ready to, transmitting carries the low frequency magnetic field signal of card reader Frame information Idr digital information continuously;
The channel information of the RF module that further, contains card reader in Frame information Idr; Further, the channel information of the RF module of card reader is that 2480MHz is to a channel between 2483MHz;
Precondition 6: the frequency f0 of low frequency operation determines according to abovementioned steps;
Precondition 7: the method that the multiplication factor A of the low-frequency amplifier circuit of RF IC card/radio frequency storage card and thresholding Vt have controlled according to aforementioned error sets.
Realize RF IC card/radio frequency storage card of the method as previously mentioned.
Realization swipe the card operation process as follows:
1, the mobile terminal that aforementioned RF IC card/radio frequency storage card is housed is during near card reader, and the low-frequency magnetic sensor circuit 1206 of RF IC card/radio frequency storage card is transformed to low frequency magnetic field voltage signal 1302 by the low frequency magnetic field signal 1301 of present position.Low-frequency magnetic sensor circuit 1206, low frequency amplifier circuit 1215 and comparison circuit 1225 are low power consumption modules, and source current consumption during its work is less than 300uA.Low-frequency magnetic sensor circuit 1206, low-frequency amplifier circuit 1215 and comparison circuit 1225 can continuous operations, and the source current of consumption is little, and the battery standby of battery powered mobile terminal is not had to large impact service time.Other module most of the time in RF IC card/radio frequency storage card is in resting state, substantially electric consumption electric current not;
2, low-frequency magnetic sensor circuit 1206 is given the low-frequency amplifier circuit 1215 in low frequency signal reception and processing module 1205 by low frequency magnetic field voltage signal 1302, and the voltage signal 1303 after low-frequency amplifier circuit 1215 amplifies is given comparison circuit 1225 and decoding circuit 1245.Further, if radio frequency sim card, it is shaped as rectangle, its size is 25mm*15mm, by 4 circles, the pcb coil along sim card housing forms low-frequency magnetic sensor circuit 1206, such low-frequency magnetic sensor circuit 1206 in differential constant amplitude is ± magnetic field of 26500A/m/s in, the peak voltage signal of will sense ± 50uV, peak-to-peak value is 100uV;
3, comparison circuit 1225 compares voltage signal 1303 with threshold voltage Vt, and gives the second primary processor 1201 by comparative result.If comparative result is greater than Vt, wake other module of card up and work together, otherwise other module continues dormancy;
If 4 voltage signals 1303 are greater than threshold voltage Vt, the second primary processor 1201 is controlled 1245 pairs of voltage signals of receiving 1303 of decoding circuit and is decoded, and obtains card reader Idr digital information.Decoding circuit 1245 is given the second primary processor 1201 by the card reader Idr digital information decoding;
5, the second primary processor 1201 is received after effective card reader Idr, therefrom find out channel information CH, control RF transmission circuit 1203 and pass through RF antenna 1204 with channel CH and card reader communication, foundation only has the RF communication channel CH that current card reader and RF IC card/radio frequency storage card can communication, and the card reader Idr receiving is sent to card reader by RF communication channel;
Whether the Idr that 6, card reader judgement is received from RF communication channel is the own Idr sending from low frequency magnetic field signal, if not, refusal communication, if correct, starts the communication of follow-up and card until complete the required operation of swiping the card.Operating process RF IC card/radio frequency storage card and the card reader of swiping the card needs RF communication repeatedly, carrying out in RF communication process at every turn, card all will go to judge whether voltage signal 1303 is less than threshold voltage Vt, if be less than Vt, finishes immediately RF communication, finishes the operation of swiping the card also not completing.RF IC card/radio frequency storage card and mobile terminal interaction data in operating process if swiped the card, can realize by interface module 1207.After swiping the card and having operated, except low frequency signal receive and processing module 1205 in low-frequency magnetic sensor circuit 1206, low-frequency amplifier circuit 1215 and comparison circuit 1225 module continue sleep, be continued until that voltage 1303 that next low frequency magnetic field signal is corresponding is from being less than Vt to the operation of swiping the card being greater than the variation of Vt.
7, the realization of the operating function of swiping the card of mobile terminal payment coordinates card reader to complete by the second primary processor 1201, SIM/UIM/USIM/TF/SD/MMC card module, RF transmission circuit 1203 and RF antenna 1204 together;
8, SIM/UIM/USIM/TF/SD/MMC card module completes its due function, when realizing its function, and be by the second primary processor 1201 and interface module 1207 and mobile terminal interaction data.
Adopt the present invention, can realize the short-range communication without calibration, such as paying by mails etc.
The foregoing is only preferred embodiment of the present invention, in order to limit the present invention, within the spirit and principles in the present invention not all, any modification of doing, be equal to replacement, improvement etc., within all should being included in protection scope of the present invention.

Claims (14)

1. a mobile radio device, it is characterized in that, comprise at least one low-frequency magnetic sensor circuit, at least one low-frequency amplifier circuit, at least one thresholding judgement and demodulator circuit, at least one second primary processor, at least one radio-frequency (RF) transmit-receive circuit and at least one radio-frequency antenna, described low-frequency magnetic sensor circuit, low-frequency amplifier circuit, thresholding judgement and demodulator circuit, the second primary processor, radio-frequency (RF) transmit-receive circuit, radio-frequency antenna connection in sequential series;
Wherein, the low frequency receiver that described low-frequency magnetic sensor circuit, low-frequency amplifier circuit, thresholding judgement and demodulator circuit form works in previously selected system without the frequency below the highest frequency f0 of calibration operation.
2. mobile radio device according to claim 1, it is characterized in that, described low-frequency magnetic sensor circuit is coil, low-frequency magnetic sensor circuit conversion gain is to swipe the card farthest apart from corresponding systemic presupposition value with the applied system of mobile radio device place mobile terminal with the product of the multiplication factor of low-frequency amplifier circuit, the volume of described low frequency receiver depends on the multiplication factor of described low-frequency magnetic sensor circuit conversion gain and low-frequency amplifier circuit, the volume of low frequency receiver increases with the increase of low-frequency magnetic sensor circuit conversion gain, or the minimizing with low-frequency amplifier circuit multiplication factor increases.
3. mobile radio device according to claim 1, it is characterized in that, described system without the highest frequency f0 of calibration operation in ultra-low frequency frequency range or very low frequency frequency range or low frequency frequency range, the frequency range of described ultra-low frequency frequency range is 300Hz～3000Hz, the frequency range of described very low frequency frequency range is 3KHz～30KHz, and the frequency range of described low frequency frequency range is 30KHz～300KHz.
4. mobile radio device according to claim 3, is characterized in that, described system is 300Hz～50KHz without the residing frequency range of highest frequency f0 of calibration operation.
5. mobile radio device according to claim 4, is characterized in that, described system is 500Hz, 1KHz, 1.5KHz, 2KHz, 2.5KHz, 3KHz, 4KHz, 5KHz, 10KHz, 20KHz or 30KHz without the highest frequency f0 of calibration operation.
6. mobile radio device according to claim 1, is characterized in that, described thresholding judgement and demodulator circuit are comprised of interconnective comparison circuit and decoding circuit.
7. mobile radio device according to claim 1, is characterized in that, described thresholding judgement and demodulator circuit are comprised of the comparison circuit being connected in turn, demodulator circuit and decoding circuit.
8. mobile radio device according to claim 1, is characterized in that, described low-frequency magnetic sensor circuit is PCB coil, enamel wire coil, hall device or giant reluctivity device.
9. mobile radio device according to claim 1, is characterized in that, described mobile radio device is placed in mobile terminal.
10. mobile radio device according to claim 9, is characterized in that, described mobile radio device is placed in SIM card, UIM card, usim card, TF card, SD card or the mmc card in mobile terminal.
11. mobile radio devices according to claim 10, is characterized in that, the processor in described the second primary processor and SIM/UIM/USIM/TF/SD/MMC card is same common processor.
12. mobile radio devices according to claim 9, is characterized in that, described mobile terminal is mobile phone, personal digital assistant PDA or notebook computer.
13. 1 kinds of RF IC cards, is characterized in that, comprise the mobile radio device described in claim 1 to 12 any one.
14. 1 kinds of radio frequency storage cards, is characterized in that, comprise the mobile radio device described in claim 1 to 12 any one.
CN201010124327.1A 2010-03-15 2010-03-15 Mobile radio frequency device, radio frequency IC (Integrated Circuit) card and radio frequency storage card Active CN102196605B (en)

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CN201010124327.1A CN102196605B (en) 2010-03-15 2010-03-15 Mobile radio frequency device, radio frequency IC (Integrated Circuit) card and radio frequency storage card
PCT/CN2010/071416 WO2011113216A1 (en) 2010-03-15 2010-03-30 Mobile radio frequency apparatus, radio frequency integrated circuit card and radio frequency memory card
ARP110100802A AR080399A1 (en) 2010-03-15 2011-03-14 MOBILE RADIO FREQUENCY DEVICE, INTEGRATED CIRCUIT RADIO FREQUENCY CARD AND RADIO FREQUENCY STORAGE CARD

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