CN104700145A - Near field communication chip, and near field communication antenna selecting method and device - Google Patents
Near field communication chip, and near field communication antenna selecting method and device Download PDFInfo
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- CN104700145A CN104700145A CN201510147551.5A CN201510147551A CN104700145A CN 104700145 A CN104700145 A CN 104700145A CN 201510147551 A CN201510147551 A CN 201510147551A CN 104700145 A CN104700145 A CN 104700145A
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Abstract
The invention provides a near field communication chip, and a near field communication antenna selecting method and device. The method comprises the steps of S1, driving each antenna through preset signals in turn before performing near field communication; S2, measuring at least one electrical parameters generated by each antenna during driving; S3, selecting the optimal antenna with the optimal near field communication effect according to at least one electrical parameters of each antenna. According to the scheme, the method has the advantages that the optimal antenna for near field communication has a good communication effect and also has high market application value.
Description
Technical field
The present invention relates near field communication technology, in particular, a kind of near-field communication chip, near field communication antenna system of selection and device.
Background technology
NFC (Near Field Communication, near-field communication) is a kind of Near Field Communication technology, can at mobile device, consumption electronic product, to carry out communication between PC and intelligent artifact mutual.NFC has simply, the advantage of low cost, strong security, uses also very simple and convenient, is widely used at present in mobile payment, identification, intelligent appliance control.
Current NFC technique is widely applied, relate to the international standards such as ISO14443, ISO15693, ISO18092, these standards, except defining communication data Frame Protocol, have also carried out specification to technical specifications relevant to antenna physical characteristic such as operating distance, frequency, coupling scheme emphatically.In order to realize NFC communication, need antenna, this Antenna Operation, under 13.56MHz frequency, is the coil antenna of about 40mm × 30mm in typical case, generally has multiturn.
NFC coil antenna enters in the alternating magnetic field of read write line generation, and the interaction between NFC antenna and reading and writing device antenna is just similar to transformer, and both coils are equivalent to primary coil and the secondary coil of transformer; The resonant tank formed by NFC coil antenna comprises coil inductance L, stray capacitance Cp and the shunt capacitance C2 ' of antenna, and its resonance frequency is:
In formula, C is the parallel equivalent electric capacity of Cp and C2 '.NFC application system realizes two-way data communication by this frequency carrier.The outward appearance of conventional ID1 type non-contact IC card is a small-sized plastic clip (85.72mm × 54.03mm × 0.76mm), and aerial coil resonant operational frequency is generally 13.56MHz; Develop the minimum short distance RFID application system for 0.4mm × 0.4mm coil antenna of area at present.
Some application requires that NFC antenna coil shape is very little, and needs certain operating distance, as the RFID for animal identification.If coil shape is little, namely its area is little, and the aerial coil mutual induction amount M between NFC and read write line just obviously can not meet actual use.Usually the Ferrite Material with high permeability μ is inserted in NFC antenna coil inside, to increase mutual induction amount, thus the problem that compensating coil xsect reduces.
For NFC card reader, the design of antenna is more exquisite, and better antenna performance will provide the performance of product, ease for use and customer experience greatly.At present in a lot of occasion, single antenna can not meet the demands, and has progressively occurred the card reader with many antennas, and this has just occurred the problem how using these antenna.
NFC antenna needs resonance on 13.56MHz, if simple for many antennas in parallel or series connection, so due to overall electric capacity or inductance excessive, resonance frequency will step-down, can not meet the demands, select to connect one of them antenna according to current situation when common scheme is each communication, therefore how to select optimal antenna extremely important.
But prior art fails to solve the problem.
Summary of the invention
Technical matters to be solved by this invention is to provide a kind of new near-field communication chip, near field communication antenna system of selection and device.
Technical scheme of the present invention is as follows: a kind of near field communication antenna system of selection, and it comprises the following steps: S1, before carrying out near-field communication, uses preset signals to drive each antenna in turn; S2, measures at least one electric parameter that in driving process, each antenna produces; S3, according at least one electric parameter of each antenna, selects the optimal antenna with near-field communication optimal effectiveness.
Preferably, in described near field communication antenna system of selection, after step S3, also perform following steps S4, adopt described optimal antenna to carry out near-field communication.
Preferably, in described near field communication antenna system of selection, before step S1, also perform following steps S10, respond to outside near-field communication device.
Preferably, in described near field communication antenna system of selection, in step S4, described optimal antenna and described near-field communication device is adopted to carry out near-field communication.
Preferably, in described near field communication antenna system of selection, in step S4, adopt multi-way switch switching mode, select described optimal antenna.
Preferably, in described near field communication antenna system of selection, in step S1, when using preset signals to drive each antenna in turn, by multi-way switch, described preset signals is driven on each antenna successively.
The another technical scheme of the present invention is as follows: a kind of near field communication antenna selecting arrangement, and it comprises signal generating circuit, multi-way switch, metering circuit, control circuit; Described control circuit connects described signal generating circuit, described metering circuit respectively; Described signal generating circuit, described metering circuit connect described multi-way switch respectively; Described multi-way switch is for connecting outside some antennas.
Preferably, in described near field communication antenna selecting arrangement, described control circuit is also for reception control signal, transmission indicator signal; Described multi-way switch is also for external transceiving data.
Preferably, described near field communication antenna selecting arrangement also comprises described some antennas.
Another technical scheme of the present invention is as follows: a kind of near-field communication chip, and it comprises arbitrary above-mentioned near field communication antenna selecting arrangement.
Adopt such scheme, the present invention adopts described optimal antenna to carry out near-field communication, and communication effect is better, has very high market using value.
Accompanying drawing explanation
Fig. 1 is the schematic diagram of an embodiment of near field communication antenna selecting arrangement of the present invention;
Fig. 2 is NFC antenna Measuring Time schematic diagram of the present invention;
Fig. 3 is the schematic diagram of another embodiment of near field communication antenna selecting arrangement of the present invention;
Fig. 4 is the schematic diagram of another embodiment of near field communication antenna selecting arrangement of the present invention.
Embodiment
For the ease of understanding the present invention, below in conjunction with the drawings and specific embodiments, the present invention will be described in more detail.Give preferred embodiment of the present invention in this instructions and accompanying drawing thereof, but the present invention can realize in many different forms, is not limited to the embodiment described by this instructions.On the contrary, provide the object of these embodiments be make the understanding of disclosure of the present invention more comprehensively thorough.
It should be noted that, when a certain element is fixed on another element, comprise and this element is directly fixed on this another element, or this element is fixed on this another element by least one other element placed in the middle.When an element connects another element, comprise and this element is directly connected to this another element, or this element is connected to this another element by least one other element placed in the middle.
One embodiment of the present of invention are, a kind of near field communication antenna system of selection, and it comprises the following steps: S1, before carrying out near-field communication, use preset signals to drive each antenna in turn; S2, measures at least one electric parameter that in driving process, each antenna produces; S3, according at least one electric parameter of each antenna, selects the optimal antenna with near-field communication optimal effectiveness.Such as, in step S1, preset signals adopts experience arrange or in use adjust.And for example, in step S2, only measure the electric parameter that in driving process, each antenna produces, such as, described electric parameter is electric current, and and for example, in step S3, first according to the size of current of each antenna, the antenna selecting electric current maximum is as described optimal antenna; Or when the electric current of at least two antennas is identical, selection any antenna is wherein as described optimal antenna.And for example, in step S2, adopt the modes such as current detecting, voltage detecting, inductance detection and/or power detection, measure at least one electric parameter that in driving process, each antenna produces.And for example, in step S3, according to the size of current of each antenna, select the optimal antenna with near-field communication optimal effectiveness; Such as, the antenna selecting electric current maximum is as described optimal antenna.And for example, in step S3, first according to the size of current of each antenna, the antenna selecting electric current maximum is as described optimal antenna; When electric current is identical, according to the voltage swing of each antenna, the antenna selecting voltage maximum is as described optimal antenna; And for example, when electric current and the voltage homogeneous phase of at least two antennas while, selection any antenna is wherein as described optimal antenna; And for example, when electric current and the voltage homogeneous phase of some antennas while, selection any antenna is wherein as described optimal antenna; And for example, when electric current and the voltage homogeneous phase of some antennas while, the antenna selecting inductance maximum is as described optimal antenna.Wherein, detection or the measurement of each electric parameter all can adopt existing techniques in realizing, and the present invention and each embodiment thereof are effectively applied at this, can realize the technique effect selecting optimal antenna.
Such as, a kind of near field communication antenna system of selection, it comprises the following steps: S1, before carrying out near-field communication, uses preset signals to drive each antenna in turn; S2, measures at least one electric parameter that in driving process, each antenna produces; S3, according at least one electric parameter of each antenna, selects the optimal antenna with near-field communication optimal effectiveness; S4, adopts described optimal antenna to carry out near-field communication.As shown in Figure 2, for NFC antenna Measuring Time schematic diagram of the present invention, the order from card reader should be able to be responded in 5ms after the card that NFC standard specifies is placed on magnetic field, in figure, t0 to t1 is exactly this time, and the method for the invention and device are exactly the selection realizing optimal antenna in this time.Preferably, in step S4, carrying out in near-field communication process, continuing to perform step S1 by predetermined period; Such as, described predetermined period adjusts according to practical application, or described predetermined period is 50% of the averaged communication time value of near-field communication; Preferably, carry out near-field communication at every turn, then record its communication time value, such as 100ms, 500ms, 1200ms etc.; Then the mean time value of nearest X time is added up; Wherein, X carries out arranging or adjusting according to practical application; Such as, X=5 or 10.Then at interval of the time of predetermined period, a step S1 and subsequent step thereof is performed; Such as, mean time value is 800ms, and predetermined period is 400ms; Like this, carry out the near-field communication time longer time, the better antenna of signal can be changed.And for example, X is that described mean time value rounds acquisition divided by after the difference of twice predetermined period; Like this, predetermined period can flexibly according to service condition adjustment, laminating applied environment, and such as business is super, mobile phone, telepilot etc.
And for example, a kind of near field communication antenna system of selection, it comprises the following steps: S10, responds to outside near-field communication device; S1, before carrying out near-field communication, uses preset signals to drive each antenna in turn; Preferably, in step S1, when using preset signals to drive each antenna in turn, by multi-way switch, described preset signals is driven on each antenna successively; S2, measures at least one electric parameter that in driving process, each antenna produces; S3, according at least one electric parameter of each antenna, selects the optimal antenna with near-field communication optimal effectiveness; S4, adopts described optimal antenna to carry out near-field communication.Such as, in step S10, when sensing near-field communication device, then performing step S1, before carrying out near-field communication, using preset signals to drive each antenna in turn; Such as, induction module or multi-way switch is adopted to respond to described near-field communication device.Preferably, in step S4, described optimal antenna and described near-field communication device is adopted to carry out near-field communication.Preferably, in step S4, adopt multi-way switch switching mode, select described optimal antenna; Such as, adopt data selector module to switch and select described optimal antenna.
And for example, a kind of NFC antenna system of selection, comprise the steps: to adopt near field communication antenna selecting arrangement described in any embodiment, before carrying out near-field communication, a preset signals is produced by its signal generating circuit, then use preset signals to be driven on each antenna successively by multi-way switch, drive each antenna in turn; Then measure at least one electric parameter that in driving process, each antenna produces, such as, metering circuit measures the electric parameter in driving process simultaneously; Afterwards according at least one electric parameter of each antenna, select the optimal antenna with near-field communication optimal effectiveness; Such as, judge according to electric parameter and select optimal antenna.Like this, while use one preset signals driving N FC antenna, measure the electric parameter in driving process.Preset signals can rule of thumb be arranged or according to practical application adjustment, various embodiments of the present invention all do not impose any restrictions this, such as, adopt the type of drive of prior art, only need it can realize driving N FC antenna.Multiple NFC antenna is used to be improve a kind of important method of NFC communication effect, the each related embodiment of the present invention provides the method that can be used for selecting optimal antenna from multiple antenna, such as, described near field communication antenna system of selection comprises the certain signal of use, i.e. preset signals, drives each antenna in turn, measures the electric parameter in driving process simultaneously, thus judge which antenna and communication the opposing party have best communication effect, then select this antenna and communication the opposing party to carry out communication.
And for example, a kind ofly to select and the method being connected optimum N FC antenna when there is multiple NFC antenna, described NFC antenna system of selection uses certain electric signal, drives each NFC antenna in turn by multi-way switch, measure the electric parameter in the process of motivation simultaneously, carry out analyzing, differentiating, thus selected optimal antenna.Such as, exciting circuit produces preset signals, is driven on each antenna successively by multi-way switch, and metering circuit measures the electric parameter in driving process simultaneously, then judges according to electric parameter and selects optimal antenna.And for example, the present invention proposes the device realizing described NFC antenna system of selection, comprising the signal generating circuit producing pumping signal, comprising the multi-way switch for connecting respective antenna, comprise the metering circuit measuring electric parameter in driving process, and realize the control circuit of measuring process.
Adopt near field communication antenna system of selection described in above-mentioned any embodiment, further embodiment of this invention is as follows: a kind of near field communication antenna selecting arrangement, and it comprises signal generating circuit, multi-way switch, metering circuit, control circuit; Described control circuit connects described signal generating circuit, described metering circuit respectively; Described signal generating circuit, described metering circuit connect described multi-way switch respectively; Described multi-way switch is for connecting outside some antennas.Preferably, described control circuit also connects described multi-way switch.Preferably, described signal generating circuit adopts exciting circuit to realize; Or described signal generating circuit is exciting circuit; Such as, exciting circuit load have electric current by time, realize corona discharge, thus before carrying out near-field communication, use preset signals to drive each antenna in turn.Preferably, described near field communication antenna selecting arrangement also comprises described some antennas.Preferably, described multi-way switch is a data selector module.Such as, the generation of signal generating circuit, multi-way switch or the communication of control circuit inductive near field is adopted.And for example, the generation of the independent inductive near field communication of induction module is adopted.
Such as, a kind of near field communication antenna selecting arrangement, it adopts near field communication antenna system of selection described in above-mentioned any embodiment to realize.
Such as, a kind of near field communication antenna selecting arrangement, it comprises signal generating circuit, multi-way switch, metering circuit, control circuit; Described control circuit connects described signal generating circuit, described metering circuit respectively, for before carrying out near-field communication, controls described signal generating circuit and drives each antenna in turn; Described signal generating circuit, described metering circuit connect described multi-way switch respectively; Described multi-way switch is for connecting outside some antennas; Described signal generating circuit is for being driven into each antenna by described multi-way switch successively by described preset signals; At least one electric parameter that described metering circuit produces for measuring each antenna in driving process.Preferably, in described near field communication antenna selecting arrangement, described control circuit is also for reception control signal, transmission indicator signal; Described multi-way switch is also for external transceiving data.
As shown in Figure 1, an embodiment of near field communication antenna selecting arrangement of the present invention is, a kind of NFC antenna selecting arrangement, it comprises the exciting circuit producing pumping signal, comprise the multi-way switch for connecting respective antenna, comprise the metering circuit measuring electric parameter in driving process, and realize the control circuit of measuring process; Described control circuit connects described exciting circuit, described metering circuit, described multi-way switch respectively; Described exciting circuit, described metering circuit connect described multi-way switch respectively; Described multi-way switch connects outside some antennas.Preferably, described near field communication antenna selecting arrangement also comprises described some antennas.Like this, just achieving by using certain excitation to be applied in NFC antenna, measuring respective electric parameter to select the device of optimal antenna simultaneously.Such as, wherein, metering circuit is measurement of electric parameter circuit or measurement of electric parameter decision circuitry.Like this, can be used for selecting optimal antenna from multiple antenna, realize preferably communication effect.And for example, described exciting circuit comprises control module and under the control of described control module, produces the level shift module encouraging control signal, preferably, described exciting circuit also comprises signal-applying module, for the steering order according to described control module, excitation control signal is applied to each antenna.And for example, described exciting circuit comprises the impact damper U, electric capacity C, P raceway groove isolated gate FET Q and sensor T that are linked in sequence; One diode D is set between impact damper U and electric capacity C, its plus earth; The grid of P raceway groove isolated gate FET Q connects electric capacity C, and also a resistance R in parallel is at the grid of P raceway groove isolated gate FET Q and source electrode, and the drain electrode of P raceway groove isolated gate FET Q is by sensor T ground connection.Between the source electrode of resistance R and P raceway groove isolated gate FET Q, a pumping signal end is set.
Another embodiment of the present invention is as follows: a kind of near-field communication chip, and it comprises arbitrary above-mentioned near field communication antenna selecting arrangement; As shown in Figure 3, an independently near-field communication chip made by described near field communication antenna selecting arrangement, it comprises exciting circuit, multi-way switch, metering circuit and control circuit, make an independent chip or module, outside control signal startup work is received during work, carry out the selection of optimal antenna by near field communication antenna system of selection described in arbitrary related embodiment, externally provide indicator signal in the process, so that the outside duty understanding current whole antenna selection circuit.
Antenna selection circuit is operated in t0 to the t1 time shown in Fig. 2, such as, the order from card reader should be able to be responded in 5ms after the card that NFC standard specifies is placed on magnetic field, in figure, t0 to t1 is exactly this time, and near field communication antenna system of selection and device described in various embodiments of the present invention are exactly the selection realizing optimal antenna in this time.
After completing day line options, antenna selection circuit provides signal designation, antenna selection circuit entry communication state, and the data to be sent that external circuit is sent here are delivered on selected antenna by multi-way switch.Selected antenna receives signal also can deliver to external circuit by multi-way switch.
Shown in Fig. 4, near field communication antenna selecting arrangement described in various embodiments of the present invention is incorporated in a complete near-field communication chip, which illustrates this device as the situation being incorporated into complete chip inside; Described device comprises exciting circuit, multi-way switch, metering circuit and control circuit, module integrated to chip internal as one, become a complete chip, circuit sending control signal during work beyond NFC antenna selection circuit starts antenna selection circuit work, by near field communication antenna system of selection described in arbitrary related embodiment, carry out the selection of optimal antenna, externally provide indicator signal in the process, so that the outside duty understanding current whole antenna selection circuit.
Antenna selection circuit is operated in t0 to the t1 time shown in Fig. 2, realizes the selection of optimal antenna in this time.After completing day line options, antenna selection circuit provides signal designation, antenna selection circuit entry communication state, and the data to be sent that external circuit is sent here are delivered on selected antenna by multi-way switch.Selected antenna receives signal also can deliver to external circuit by multi-way switch.
Further, embodiments of the invention also comprise, each technical characteristic of the various embodiments described above, the near-field communication chip be mutually combined to form, near field communication antenna system of selection and device, such as it is applied in NFC antenna by using certain excitation, measure respective electric parameter to select optimal antenna simultaneously, thus effectively can promote the accuracy of day line options, thus improve efficiency and the accuracy rate of near-field communication.It should be noted that, above-mentioned each technical characteristic continues combination mutually, is formed not in above-named various embodiment, is all considered as the scope that instructions of the present invention is recorded; Further, for those of ordinary skills, can be improved according to the above description or convert, and all these improve and convert the protection domain that all should belong to claims of the present invention.
Claims (10)
1. a near field communication antenna system of selection, is characterized in that, comprises the following steps:
S1, before carrying out near-field communication, uses preset signals to drive each antenna in turn;
S2, measures at least one electric parameter that in driving process, each antenna produces;
S3, according at least one electric parameter of each antenna, selects the optimal antenna with near-field communication optimal effectiveness.
2. near field communication antenna system of selection according to claim 1, is characterized in that, after step S3, also performs following steps S4, adopts described optimal antenna to carry out near-field communication.
3. near field communication antenna system of selection according to claim 2, is characterized in that, before step S1, also performs following steps S10, responds to outside near-field communication device.
4. near field communication antenna system of selection according to claim 3, is characterized in that, in step S4, adopts described optimal antenna and described near-field communication device to carry out near-field communication.
5. near field communication antenna system of selection according to claim 4, is characterized in that, in step S4, adopts multi-way switch switching mode, selects described optimal antenna.
6. near field communication antenna system of selection according to claim 5, is characterized in that, in step S1, when using preset signals to drive each antenna in turn, described preset signals is driven into successively on each antenna by multi-way switch.
7. a near field communication antenna selecting arrangement, is characterized in that, comprises signal generating circuit, multi-way switch, metering circuit, control circuit;
Described control circuit connects described signal generating circuit, described metering circuit respectively;
Described signal generating circuit, described metering circuit connect described multi-way switch respectively;
Described multi-way switch is for connecting outside some antennas.
8. near field communication antenna selecting arrangement according to claim 7, is characterized in that, described control circuit also for reception control signal, send indicator signal; Described multi-way switch is also for external transceiving data.
9. near field communication antenna selecting arrangement according to claim 8, is characterized in that, also comprise described some antennas.
10. a near-field communication chip, is characterized in that, comprise as arbitrary in claim 7 to 9 as described near field communication antenna selecting arrangement.
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| CN201510147551.5A CN104700145A (en) | 2015-03-31 | 2015-03-31 | Near field communication chip, and near field communication antenna selecting method and device |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN108696303A (en) * | 2017-03-30 | 2018-10-23 | 京瓷办公信息系统株式会社 | Antenna substrate and image forming apparatus |
| CN111525265A (en) * | 2020-05-22 | 2020-08-11 | 闻泰通讯股份有限公司 | Antenna tuning system, electronic equipment and antenna tuning method |
| CN112448146A (en) * | 2019-08-30 | 2021-03-05 | Oppo广东移动通信有限公司 | Antenna device, electronic equipment and antenna switching method |
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| CN103414507A (en) * | 2013-07-26 | 2013-11-27 | 北京小米科技有限责任公司 | Mobile terminal and method and device for switching antennas of mobile terminal |
| US20140197991A1 (en) * | 2013-01-15 | 2014-07-17 | Disney Enterprises, Inc. | Spatial recognition of rfid tag placement using antenna multiplexing |
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| US20140197991A1 (en) * | 2013-01-15 | 2014-07-17 | Disney Enterprises, Inc. | Spatial recognition of rfid tag placement using antenna multiplexing |
| CN103414507A (en) * | 2013-07-26 | 2013-11-27 | 北京小米科技有限责任公司 | Mobile terminal and method and device for switching antennas of mobile terminal |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN108696303A (en) * | 2017-03-30 | 2018-10-23 | 京瓷办公信息系统株式会社 | Antenna substrate and image forming apparatus |
| CN112448146A (en) * | 2019-08-30 | 2021-03-05 | Oppo广东移动通信有限公司 | Antenna device, electronic equipment and antenna switching method |
| US11329374B2 (en) | 2019-08-30 | 2022-05-10 | Guangdong Oppo Mobile Telecommunications Corp., Ltd. | Antenna device, electronic apparatus and method for antenna switching |
| CN111525265A (en) * | 2020-05-22 | 2020-08-11 | 闻泰通讯股份有限公司 | Antenna tuning system, electronic equipment and antenna tuning method |
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