CN103020562B - Ultrahigh frequency radio frequency identification device (RFID) self-adaptive antenna impedance matching method - Google Patents
Ultrahigh frequency radio frequency identification device (RFID) self-adaptive antenna impedance matching method Download PDFInfo
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Abstract
The invention provides an ultrahigh frequency radio frequency identification device (RFID) self-adaptive antenna impedance matching method which includes step1 providing a reader which comprises a reader body, an antenna impedance matching module and an antenna which comprises a digital signal processing control system, a reflection power detection unit and a self-adaptive antenna impedance matching module; step2 providing an RFID label and enabling the reader to transmit an operation command to the RFID label which transmits signals in one frequency to the external; step 3 enabling the reader to receive the signals and the reflection power detection unit to start detecting real-time reflection signals of the antenna and transmit the real-time reflection signals to the digital signal processing control system; step4 enabling the digital signal processing control system to calculate required impedance Z of the self-adaptive impedance matching module according to the real-time reflection signals; and step5 enabling the digital signal processing control system to adjust real-time impedance of the self-adaptive impedance matching module to finish communication.
Description
Technical field
The present invention relates to contactless automatic identification technology, particularly relate to a kind of ultrahigh frequency RFID adaptive antenna impedance matching methods.
Background technology
The automatic recognition system that radio-frequency recognition system (RFID system) is made up of radio-frequency (RF) tag, recognizer and computer network.Usually, recognizer forms electromagnetic field at a field emission energy, radio-frequency (RF) tag sends the data of storage after the signal that this region detects recognizer, the signal that recognizer received RF label sends, and decoding the accuracy of checking data are to reach the object of identification.Conventional has low frequency (LF) (125kHz ~ 134.2KHz), high frequency (HF) (13.56Mhz), ultrahigh frequency (860MHz ~ 960MHz) (UHF, Ultra high frequency), the technology such as passive.
Wherein, in ultrahigh frequency automatic recognition system, UHF RFID antenna is the important component part of radio-frequency recognition system, directly affect its performance and stability, and the physical environment of application scenario (as: metal goods, water etc.) very easily causes the Parameters variation of antenna, this change can produce two disadvantageous consequences: first, the emitted energy of power amplifier module can be reduced, cause module seriously generate heat and damage; Secondly, can reflective power be produced, greatly reduce the signal to noise ratio (S/N ratio) of receiving terminal circuit.Thus adaptive antenna impedance match technique is just adopted effectively to go the change of solution antenna parameter and cause the problem of impedance mismatching.
Ultrahigh frequency RFID adaptive antenna impedance match technique and high-frequency RF ID antenna automatic tuning technology and short wave communication FM radio station listening mode very similar, reached the object of Auto-matching (tuning) by the mode changing tuned cell (match circuit) impedance.To change in fact the impedor in access match circuit by the mode of relay switch and reach the object of tuning (coupling) in high-frequency RF ID.The method has certain effect to high-frequency RF ID antenna automatic tuning, but mainly has the following disadvantages:
1. hands-off tuning (coupling) precision and reliability poor;
2. impedance detection circuit metrical error is large;
3. hands-off tuning (coupling) speed is slow, cannot realize rapid adjustment;
4. tuned cell circuit volume is excessive, cost intensive, existing scientific and technological level is difficult to the microminiaturization realizing relay switch, the frequency of operation of relay support generally only has tens megahertzes in addition, its high frequency distribution parameter influence is serious, easily brings the problems such as Electro Magnetic Compatibility EMC (Electro Magnetic Compatibility)
Summary of the invention
The object of the present invention is to provide a kind of ultrahigh frequency RFID adaptive antenna impedance matching methods, adopt high frequency, at a high speed, high-precision impedance detection circuit, achieve ultrahigh frequency, at a high speed, high-precision Adaptive impedance matching, required element is few, module volume is little, cost is low.
For achieving the above object, the invention provides a kind of ultrahigh frequency RFID adaptive antenna impedance matching methods, comprise the following steps:
Step 1, reader is provided, described reader has transmission channel and receiving cable, described reader comprises: reader body, the Antenna Impedance Matching module be electrically connected with this reader body and the antenna be electrically connected with this Antenna Impedance Matching module, described Antenna Impedance Matching module comprises: digital signal processing control system, the reflective power detecting unit be electrically connected with this digital signal processing control system and the Adaptive impedance matching module with digital signal processing control system, described reflective power detecting unit and receiving cable are electrically connected, described Adaptive impedance matching module and transmission channel are electrically connected,
Step 2, provide RFID label tag, described reader is to this RFID label tag transmit operation order, and by the outside radiation carrier signal of transmission channel after sending operational order, described RFID label tag receives this carrier signal and is converted into electric energy, for self work, and outwards launch the signal of a certain frequency;
Step 3, described reader receive the signal that this RFID label tag is launched, and described reflective power detecting unit starts the real-time reflection signals detecting antenna, and this real-time reflection signals is sent to digital signal processing control system;
Step 4, described digital signal processing control system calculate reflection coefficient S according to this real-time reflection signals
11, and according to formula (S
11+ Z
0)/(S
11-Z
0) calculate the impedance Z of required Adaptive impedance matching module, wherein, Z
0for characteristic impedance of antenna;
Step 5, described digital signal processing control system regulate the real-time impedance of Adaptive impedance matching module according to the impedance Z of the required Adaptive impedance matching module calculated, thus complete whole communication process.
Described Antenna Impedance Matching module also comprises an A/D analog to digital converter, described A/D analog to digital converter is electrically connected between reflective power detecting unit and digital signal processing control system, reflective power detecting unit is passed the simulating signal of coming and converts digital signal to, and this digital signal is sent to digital signal processing control system.
Described reflective power detecting unit comprises: directional coupler and the reflected power detector be electrically connected with this directional coupler, described reflected power detector and A/D analog to digital converter are electrically connected.
In described step 2, the signal of a certain frequency that RFID label tag is outwards launched is stored in this RFID label tag in advance.
Reflection coefficient S in described step 4
11calculate according to the antenna real-time reflection signals that the real-time radiation power that reader transmission channel is launched and reflective power detecting unit detect.
Described Adaptive impedance matching module comprises: control and drive system, several electric capacity and several gauge tap, each electric capacity one end described and a gauge tap are electrically connected, this gauge tap other end and antenna are electrically connected, and described gauge tap is also electrically connected with control and drive system.
The described control and drive system other end and digital signal processing control system are electrically connected, and control being turned on or off of each gauge tap according to the control signal that digital signal processing control system sends.
Described several gauge tap is several field effect transistor, each field effect transistor comprises: grid, drain electrode and source electrode, each grid described and control and drive system are electrically connected, and described every one source pole and an electric capacity are electrically connected, and each drain electrode described is electrically connected with antenna.
Beneficial effect of the present invention: the signal power that ultrahigh frequency RFID adaptive antenna impedance matching methods of the present invention adopts directional coupler and reflected power detector detection antenna to receive, and be converted to digital signal by A/D analog to digital converter, digital signal processing control system is according to the reactance of this Digital Signals Adaptive impedance matching module, so that impedance reaches fast automatic and mates between reader with antenna, the method adopts high frequency, at a high speed, high-precision impedance detection circuit, achieve ultrahigh frequency, at a high speed, high-precision Adaptive impedance matching, required element is few, module volume is little, cost is low, also adopt digital control technology, avoid the problems such as Electro Magnetic Compatibility EMC of the prior art.
In order to further understand feature of the present invention and technology contents, refer to following detailed description for the present invention and accompanying drawing, but accompanying drawing only provides reference and explanation use, is not used for being limited the present invention.
Accompanying drawing explanation
Below in conjunction with accompanying drawing, by the specific embodiment of the present invention describe in detail, will make technical scheme of the present invention and other beneficial effect apparent.
In accompanying drawing,
Fig. 1 is the process flow diagram of ultrahigh frequency RFID adaptive antenna impedance matching methods of the present invention;
Fig. 2 is reader and RFID label tag syndeton schematic diagram in ultrahigh frequency RFID adaptive antenna impedance matching methods of the present invention;
Fig. 3 is the structural representation of Adaptive impedance matching module preferred embodiment in Fig. 2.
Embodiment
For further setting forth the technological means and effect thereof that the present invention takes, be described in detail below in conjunction with the preferred embodiments of the present invention and accompanying drawing thereof.
Refer to Fig. 1 to 3, the invention provides a kind of ultrahigh frequency RFID adaptive antenna impedance matching methods, comprise the following steps:
Step 1, reader 20 is provided, described reader 20 has transmission channel and receiving cable, described reader 20 comprises: reader body 24, the Antenna Impedance Matching module 22 be electrically connected with this reader body 24 and the antenna 26 be electrically connected with this Antenna Impedance Matching module 22, described Antenna Impedance Matching module 22 comprises: digital signal processing control system 25, the reflective power detecting unit 29 be electrically connected with this digital signal processing control system 25 and the Adaptive impedance matching module 27 with digital signal processing control system 25, described reflective power detecting unit 29 is electrically connected with receiving cable, described Adaptive impedance matching module 27 is electrically connected with transmission channel,
Described reader 20 works and to be made up of transmission channel and receiving cable, described reader body 24 carries out radio communication by antenna 26 and RFID label tag 40, can realize the reading to RFID label tag 40 identification code and internal storage data or write operation, it generally includes the modules such as high-frequency model (transmitter and receiver) and control module.
Described Antenna Impedance Matching module 22 also comprises an A/D analog to digital converter 28, described A/D analog to digital converter 28 is electrically connected between reflective power detecting unit 29 and digital signal processing control system 25, reflective power detecting unit 29 is passed the simulating signal of coming and converts digital signal to, and this digital signal is sent to digital signal processing control system 25.Described reflective power detecting unit 29 comprises: directional coupler 292 and the reflected power detector 294 be electrically connected with this directional coupler 292, and described reflected power detector 294 is electrically connected with A/D analog to digital converter 28.The Signal separator of a certain frequency adopting directional coupler 292 to be launched by the described RFID label tag 40 that antenna 26 receives by reader body 24 out, is delivered to reflected power detector 294, is carried out power detection.Adopt digital measuring circuit have high frequency, at a high speed, the advantage such as high precision.
Described Adaptive impedance matching module 27 comprises: control and drive system 272, several electric capacity C and several gauge tap K, described each electric capacity C one end and a gauge tap K are electrically connected, this gauge tap K other end and antenna 26 are electrically connected, and described gauge tap K is also electrically connected with control and drive system 272.Described control and drive system 272 can control separately conducting or the cut-off of each gauge tap K, thus makes this Adaptive impedance matching module 27 produce required reactance.This Adaptive impedance matching module 27 adopts up-to-date UltraCMOS technical matters to produce, can realize ultrahigh frequency, at a high speed, high-precision Adaptive impedance matching.Described control and drive system 272 other end and digital signal processing control system 25 are electrically connected, and control being turned on or off of each gauge tap K according to the control signal that digital signal processing control system 25 sends, and then regulate the output impedance of Adaptive impedance matching module 27.In this preferred embodiment, described several gauge tap K is several field effect transistor Q, safe and reliable, long service life.Each field effect transistor Q comprises: grid g, drain electrode d and source electrode s, and preferably, described each grid g and control and drive system 272 are electrically connected, and a described every one source pole s and electric capacity C is electrically connected, and each drain electrode d described and antenna 26 are electrically connected.
Step 2, provide RFID label tag 40, described reader 20 is to this RFID label tag 40 transmit operation order, and by the outside radiation carrier signal of transmission channel after sending operational order, described RFID label tag 40 receives this carrier signal and is converted into electric energy, for self work, and outwards launch the signal of a certain frequency;
The signal of the outside a certain frequency of launching of described RFID label tag 40 is stored in this RFID label tag 40 in advance in this step, after described reader 20 passes through to read this signal, through processing thus can identifying this RFID label tag 40.Described RFID label tag 40 is passive label, is converted to electric energy, and then carries out work by receiving the carrier signal of the non-modulated of reader 20 radiation.
Step 3, described reader 20 receive the signal that this RFID label tag 40 is launched, and described reflective power detecting unit 29 starts the real-time reflection signals detecting antenna, and this real-time reflection signals is sent to digital signal processing control system 25;
In this step, described reflective power detecting unit 29 starts the real-time reflection signals detecting antenna 26, by A/D analog to digital converter 28, simulating signal is converted to digital signal, achieves high speed, high precision test.
Step 4, described digital signal processing control system 25 calculate reflection coefficient S according to this real-time reflection signals
11, and according to formula (S
11+ Z
0)/(S
11-Z
0) calculate the impedance Z of required Adaptive impedance matching module 27, wherein, Z
0for characteristic impedance of antenna;
Described reflection coefficient S
11calculate according to antenna real-time reflection signals r (t) that real-time radiation power x (t) that reader 20 transmission channel is launched and reflective power detecting unit 29 detect, this computing rule is stored in described digital signal processing control system 25 in advance, in computation process, directly call.
Wherein, the impedance Z=(S of described formula Adaptive impedance matching module
11+ Z
0)/(S
11-Z
0) be obtain according to transmission theory, being turned on or off of several electric capacity C in control signal adjustment Adaptive impedance matching module 27 is exported by digital processing control system 25 according to the Z value calculated, and then the output reactance of adjustment Adaptive impedance matching module 27, make S
11minimum.
Step 5, described digital signal processing control system 25 regulate the real-time impedance of Adaptive impedance matching module 27 according to the impedance Z of Adaptive impedance matching module 27 needed for calculating, thus complete whole communication process.
In whole communication process, antenna 26 real-time reflection signals that described digital signal processing control system 25 detects according to reflective power detecting unit 29, repeatedly regulate the output reactance of Adaptive impedance matching module 27, to allow impedance between reader 20 with antenna 26 reach fast automatic mate, make S
11remain on minimum value, Auto-matching speed is fast.
The element needed for circuit module that ultrahigh frequency RFID adaptive antenna impedance matching methods of the present invention realizes adaptation function is few, and the fast volume of module is little, and can realize microminiaturization, cost is low; Also adopt digital control technology, avoid the problems such as Electro Magnetic Compatibility EMC of the prior art.
In sum, the invention provides a kind of ultrahigh frequency RFID adaptive antenna impedance matching methods, adopt the reflected signal that directional coupler and reflected power detector detection antenna receive, and be converted to digital signal by A/D analog to digital converter, digital signal processing control system is according to the reactance of this Digital Signals Adaptive impedance matching module, so that impedance reaches fast automatic and mates between reader with antenna, the method adopts high frequency, at a high speed, high-precision impedance detection circuit, achieve ultrahigh frequency, at a high speed, high-precision Adaptive impedance matching, required element is few, module volume is little, cost is low, also adopt digital control technology, avoid the problems such as Electro Magnetic Compatibility EMC of the prior art.
The above, for the person of ordinary skill of the art, can make other various corresponding change and distortion according to technical scheme of the present invention and technical conceive, and all these change and be out of shape the protection domain that all should belong to the claims in the present invention.。
Claims (5)
1. a ultrahigh frequency RFID adaptive antenna impedance matching methods, is characterized in that, comprises the following steps:
Step 1, reader is provided, described reader has transmission channel and receiving cable, described reader comprises: reader body, the Antenna Impedance Matching module be electrically connected with this reader body and the antenna be electrically connected with this Antenna Impedance Matching module, described Antenna Impedance Matching module comprises: digital signal processing control system, the reflective power detecting unit be electrically connected with this digital signal processing control system and the Adaptive impedance matching module with digital signal processing control system, described reflective power detecting unit and receiving cable are electrically connected, described Adaptive impedance matching module and transmission channel are electrically connected,
Step 2, provide RFID label tag, described reader is to this RFID label tag transmit operation order, and by the outside radiation carrier signal of transmission channel after sending operational order, described RFID label tag receives this carrier signal and is converted into electric energy, for self work, and outwards launch the signal of a certain frequency;
Step 3, described reader receive the signal that this RFID label tag is launched, and described reflective power detecting unit starts the real-time reflection signals detecting antenna, and this real-time reflection signals is sent to digital signal processing control system;
Step 4, described digital signal processing control system calculate reflection coefficient S11 according to this real-time reflection signals, and the impedance Z of required Adaptive impedance matching module is calculated according to formula (S11+Z0)/(S11-Z0), wherein, Z0 is characteristic impedance of antenna;
Step 5, described digital signal processing control system regulate the real-time impedance of Adaptive impedance matching module according to the impedance Z of the required Adaptive impedance matching module calculated, thus complete whole communication process;
Described Antenna Impedance Matching module also comprises an A/D analog to digital converter, described A/D analog to digital converter is electrically connected between reflective power detecting unit and digital signal processing control system, reflective power detecting unit is passed the simulating signal of coming and converts digital signal to, and this digital signal is sent to digital signal processing control system;
Described reflective power detecting unit comprises: directional coupler and the reflected power detector be electrically connected with this directional coupler, described reflected power detector and A/D analog to digital converter are electrically connected.
2. ultrahigh frequency RFID adaptive antenna impedance matching methods as claimed in claim 1, it is characterized in that, in described step 2, the signal of a certain frequency that RFID label tag is outwards launched is stored in this RFID label tag in advance.
3. ultrahigh frequency RFID adaptive antenna impedance matching methods as claimed in claim 1, it is characterized in that, the antenna real-time reflection signals that in described step 4, reflection coefficient S11 detects according to the real-time radiation power that reader transmission channel is launched and reflective power detecting unit calculates.
4. ultrahigh frequency RFID adaptive antenna impedance matching methods as claimed in claim 1, it is characterized in that, described Adaptive impedance matching module comprises: control and drive system, several electric capacity and several gauge tap, each electric capacity one end described and each gauge tap are electrically connected, and each gauge tap described is also electrically connected with antenna and control and drive system;
Described several gauge tap is several field effect transistor, each field effect transistor comprises: grid, drain electrode and source electrode, each grid described and control and drive system are electrically connected, and one end of described every one source pole and each electric capacity is electrically connected, and each drain electrode described is electrically connected with antenna.
5. ultrahigh frequency RFID adaptive antenna impedance matching methods as claimed in claim 4, it is characterized in that, the described control and drive system other end and digital signal processing control system are electrically connected, and control being turned on or off of each gauge tap according to the control signal that digital signal processing control system sends.
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| CN106203584A (en) * | 2016-06-27 | 2016-12-07 | 华中科技大学 | RFID antenna impedance self-adaptive control method under a kind of bad working environments |
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| CN107682022B (en) * | 2017-09-18 | 2020-02-18 | 珠海市魅族科技有限公司 | Mobile terminal and adjusting method of antenna matching network |
| CN109447223B (en) * | 2018-10-31 | 2021-09-14 | 华大恒芯科技有限公司 | Method for enhancing reflected power of ultrahigh frequency RFID (radio frequency identification) tag |
| CN114584155B (en) * | 2020-12-02 | 2024-04-09 | 杭州海康威视数字技术股份有限公司 | Monitoring device |
| CN113420861B (en) * | 2021-06-02 | 2023-02-07 | 西安电子科技大学 | Radio frequency passive tag capable of activating self-tuning for multiple times in real time and method |
| CN115965037B (en) * | 2023-03-16 | 2023-05-30 | 深圳市明泰智能技术有限公司 | RF tag read-write system adaptive to environment change and data processing method |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20070197180A1 (en) * | 2006-01-14 | 2007-08-23 | Mckinzie William E Iii | Adaptive impedance matching module (AIMM) control architectures |
| CN101145250A (en) * | 2006-09-15 | 2008-03-19 | 财团法人工业技术研究院 | Electric vehicle power management system and method |
| CN102236069A (en) * | 2010-04-27 | 2011-11-09 | 中芯国际集成电路制造(上海)有限公司 | Test system and test method |
| CN202068407U (en) * | 2011-05-06 | 2011-12-07 | 陕西烽火电子股份有限公司 | Vector antenna tuner |
| CN102279939A (en) * | 2011-06-07 | 2011-12-14 | 上海集成电路技术与产业促进中心 | RFID tag simulator |
-
2012
- 2012-12-12 CN CN201210534922.1A patent/CN103020562B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20070197180A1 (en) * | 2006-01-14 | 2007-08-23 | Mckinzie William E Iii | Adaptive impedance matching module (AIMM) control architectures |
| CN101145250A (en) * | 2006-09-15 | 2008-03-19 | 财团法人工业技术研究院 | Electric vehicle power management system and method |
| CN102236069A (en) * | 2010-04-27 | 2011-11-09 | 中芯国际集成电路制造(上海)有限公司 | Test system and test method |
| CN202068407U (en) * | 2011-05-06 | 2011-12-07 | 陕西烽火电子股份有限公司 | Vector antenna tuner |
| CN102279939A (en) * | 2011-06-07 | 2011-12-14 | 上海集成电路技术与产业促进中心 | RFID tag simulator |
Non-Patent Citations (1)
| Title |
|---|
| 无源UHF RFID标签的低成本阻抗匹配网络设计;靳钊等;《固体电子学研究与进展》;20090630;第29卷(第2期);第215-219页 * |
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