CN106682548A - Multichannel power random change control method for RFID (radio frequency identification) reader collision preventing - Google Patents
Multichannel power random change control method for RFID (radio frequency identification) reader collision preventing Download PDFInfo
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- CN106682548A CN106682548A CN201611223351.4A CN201611223351A CN106682548A CN 106682548 A CN106682548 A CN 106682548A CN 201611223351 A CN201611223351 A CN 201611223351A CN 106682548 A CN106682548 A CN 106682548A
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- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06K—GRAPHICAL DATA READING; PRESENTATION OF DATA; RECORD CARRIERS; HANDLING RECORD CARRIERS
- G06K7/00—Methods or arrangements for sensing record carriers, e.g. for reading patterns
- G06K7/0008—General problems related to the reading of electronic memory record carriers, independent of its reading method, e.g. power transfer
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- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06K—GRAPHICAL DATA READING; PRESENTATION OF DATA; RECORD CARRIERS; HANDLING RECORD CARRIERS
- G06K7/00—Methods or arrangements for sensing record carriers, e.g. for reading patterns
- G06K7/10—Methods or arrangements for sensing record carriers, e.g. for reading patterns by electromagnetic radiation, e.g. optical sensing; by corpuscular radiation
- G06K7/10009—Methods or arrangements for sensing record carriers, e.g. for reading patterns by electromagnetic radiation, e.g. optical sensing; by corpuscular radiation sensing by radiation using wavelengths larger than 0.1 mm, e.g. radio-waves or microwaves
- G06K7/10019—Methods or arrangements for sensing record carriers, e.g. for reading patterns by electromagnetic radiation, e.g. optical sensing; by corpuscular radiation sensing by radiation using wavelengths larger than 0.1 mm, e.g. radio-waves or microwaves resolving collision on the communication channels between simultaneously or concurrently interrogated record carriers.
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Abstract
The invention discloses a multichannel power random change control method for RFID (radio frequency identification) reader collision preventing. The method includes that readers randomly select channels; 'reading rate-output power' characteristics of a single reader are measured when a same tag has different distances with the single reader, an average value of a range with maximum change is selected from a characteristic curve, and change ranges at different distances are averaged as a random change range of output power of the reader; every time when the reader completes reader-label communication, the reader output power random change range is utilized to adjust transmitting power no matter where there is label response or not. By the method, collision of readers can be avoided, and read-label collision can be reduced, so that recognition rate sum of multiple readers when recognizing labels at the same time is increased; the method is suitable for being applied in occasions of multi-reader recognition like warehouse logistics.
Description
Technical field
The present invention relates to super high frequency radio frequency identification (RFID) application, belongs to RFID anticollision technologies, it is particularly a kind of
For the multichannel power change at random control method of RFID reader anticollision.
Background technology
REID (RFID) carries out contactless two-way communication using radiofrequency signal, recognize specific target and from
The corresponding data of Target Acquisition.The technology has identification higher apart from facility remote, swift to operate, good environmental adaptability, safety
The features such as, its lifting for appearing as process of industrialization efficiency provides no small help.From warehouse logisticses to workshop management, penetrate
Frequency technology of identification suffers from being widely applied.
RFID system is mainly made up of three parts：Reader, electronic tag and main frame.When system works, calculate
Machine host controls RFID reader and launches electromagnetic wave to electronic tag according to certain communication protocol, reads when electronic tag is received
After reading the electromagnetic wave signal that device is sent, self-contained information is sent back reading by label while obtaining energy from electromagnetic wave
Device, subsequent reader is processed the information that label is returned, and completes read-write operation.
In the application such as warehouse logisticses, the identification range of reader is limited, therefore usually needs deployment multiple stage reader
The goods for posting electronic tag in monitoring certain area, is to ensure the label all standing in region, the identification between reader
Scope occurs unavoidably overlap, at this moment just there occurs " collision " of electromagnetic wave." collision " be affect recognition efficiency principal element it
One.It is the big key for lifting RFID system performance to solve the problem.
The content of the invention
The purpose of the present invention is directed in RFID system, when a label is located at multiple stage reader read range (see Fig. 1),
Multiple stage reader reads the problem that single label occurs " collision " simultaneously, proposes randomness in a kind of ultrahigh-frequency radio-frequency identification system
Changed power control method, by a series of measurement data the excursion of reader output is set, and exports reader
Power change at random in respective scope, caused by Difference of Output Power institute during changed power between different readers
Capture effect to lift many readers-mono- label condition under total reading efficiency.
The object of the present invention is achieved like this：
A kind of multichannel power change at random control method for RFID reader anticollision, the method includes following tool
Body step：
Step 1：Reader point channel
Reader randomly chooses channel；
Step 2：Random changed power scope is set
First, reader antenna and label are measured into respectively same label with single reading on same level straight line
Under different distance, " reading rate-output " characteristic of reader chooses the maximum scope of change from characteristic curve to device
The derivative of i.e. this section curve is more than the meansigma methodss of whole curve derivative, then the excursion at different distance is averaged, as
The scope of the change at random of the reader output；Subsequently, the random of other reader outputs is determined in described manner
The scope of change；Step 3：Reader reads label
(1) reader sends Select command signals and selects population of tags, concurrently sets the initial frame in the tag recognition cycle
Length is timeslot number, starts the recognition cycle of this secondary label；
(2) a READER-TO-TAG communication is often completed, regardless of whether have label to respond, using reader output
Change at random scope adjustment transmission power；
(3) if frame slot is not 0, recognition cycle is continued, reader continues to read label, until when frame slot number is kept to 0,
This recognition cycle terminates.
Each performance number weight in the range of the change at random of the reader output set by the present invention is identical, work(
The change at random of rate adopts equally distributed mode, and in the range of the changed power of respective setting random fluctuation is carried out；Work as multiple stage
When reader reads same label simultaneously, recognition rate summation gets a promotion.
It is to lift work efficiency to know disclosure is particularly well suited to apply in the larger place of the identification regions such as warehouse logisticses
Other intra-zone administration multiple stage reader reads label simultaneously, touches so that being both avoided that between reader using the method for the present invention
Hit, the recognition rate of label can be accelerated again, there is huge practical value to the application such as Internet of Things.
Description of the drawings
Fig. 1 is capture effect schematic diagram in RFID；
Fig. 2 is flow chart of the present invention；
Fig. 3 is two reader reading rates-characteristics of output power curve chart；
Fig. 4 is the contrast curve of the present invention and constant power control methods reading speed sum.
Specific embodiment
Refering to Fig. 1, capture effect refer to when multiple readers simultaneously to tag reflection signal when, only signal intensity is stronger
Signal just can be normally received by label.In figure, R1, R2 are that other are the same from two readers except transmission power difference,
The signal power of wherein R1 transmittings is larger, and the signal power of R2 transmittings is less, and label T1 is in the common reading range of R1 and R2.
When the signal of reader R1 and R2 transmitting reaches T1 simultaneously, if signal of the signal intensitys of R1 that receive of T1 much larger than R2
Intensity, then the only signal of R1 correctly demodulated by T1, i.e., now only R1 readers can normally read label.
The present invention includes step in detail below：
(1) reader point channel
Before processing many readers and seizing the collision problem of same label, the signal interference first processed between reader is asked
Topic：
Based on EPC Class1 Gen2 agreements, reader works in certain fixed frequency range, it is assumed that for USA frequency ranges, the frequency
50 data channels are had in section, each reader can at random take a data channel when working, due to place between reader
Signal interference (reader quantity is not to be exceeded channel quantity) is not mutually had in different channels, so as to avoid reader it
Between signal collision problem.
(2) random changed power scope is set
After avoiding the interference between reader, in order to reduce many readers while seizing the collision situation of same label.Such as
Shown in accompanying drawing 1, if label T1 is in the common read range of R1 and R2, T1 may simultaneously receive the signal of R1 and R2, two letters
It is superimposed number at T1 so that T1 returns correct correspondence order without normal direction R1 or R2, i.e. R1 and R2 cannot normally read T1.And
When R1 and R2 signal intensity differences are larger, T1 only and stronger signal reader proper communication.Therefore need to make reader defeated
Go out power change at random within the specific limits, so that each reader has an opportunity normally to read label.Experiment learns, reader
Reading rate to have height to have with the intensity of variation of output low, and only when the output of each reader is reading speed
In rate-larger scope of output intensity of variation during change at random, total reading rate of reader just can be larger, because now
Situation of the output far above other readers for certain reader in a certain time slot occur is more easy to, due to depositing for capture effect
The reader is easier to successfully read label under the time slot, and reduces all readers and cannot all read the situation of label occurring.
So, first respective output change at random scope is set to each reader：
First, reader antenna and label are put on same level straight line, same label is measured respectively with single reading
Under different distance, " reading rate-output " characteristic of reader chooses the maximum scope of change from characteristic curve to device
(meansigma methodss of the derivative of i.e. this section curve more than whole curve derivative), then the excursion at different distance is averaged, make
For the scope of the change at random of the reader output.Subsequently determine according to the method again other reader outputs with
The scope of machine change.
Each performance number weight in the range of set changed power is identical, therefore the change at random of power is using uniform
The mode of distribution, in the range of the changed power of respective setting random fluctuation is carried out.Performance number weight is identical be in order that each
The almost identical chance that reader has reads label, i.e., as reader R1, in lower-wattage, R2 is in the general of higher-wattage
Rate should in lower-wattage, probability of the R1 in higher-wattage be equal with R2, so can just make full use of capture effect to be lifted and read
Read device recognition rate summation.
After setting the random changed power scope of reader, reader starts to read label.Reading process is as follows：
First, reader sends Select command signals and selects population of tags, concurrently sets initial in the tag recognition cycle
Frame length (i.e. timeslot number), starts the recognition cycle of this secondary label.
Secondly, a READER-TO-TAG communication is often completed, regardless of whether have label to respond, using reader output work
Rate change at random scope adjusts transmission power.
If frame slot is not 0, continue recognition cycle, reader continues to read label, until when frame slot number is kept to 0, this
Secondary recognition cycle terminates.
When last comparative reading device adopts the present invention with reader for constant power value, the reader under different label positions
The situation of reading rate sum, it can be seen that lifted can reader reading rate sum using the present invention.
Embodiment
Refering to Fig. 2, the present embodiment includes step in detail below：
Step 1, based on EPC Class1 Gen2 agreements；Choose UHF RFID USA frequency ranges, i.e. 902.75-
927.25MHz, this frequency range one has 50 channels, and channel spacing is 500KHz.Reader randomly chooses one in frequency range used
Individual channel N, then communication frequency (902.75+N*0.5) MHz of this channel, under the few application scenario of reader quantity, adopts
The method of this kind of frequency division multiplexing, the collision that can be prevented effectively between reader.
Step 2, by measurement obtain random changed power scope.
Step 3, reader send Select command signals and select population of tags, concurrently set initial in the tag recognition cycle
Frame length (i.e. timeslot number), starts the recognition cycle of this secondary label.
Step 4, in RFID system, each inside tags has a time slot counter, when label receives reader
During QueryRep inquiry commands, enumerator subtracts 1.When the enumerator of certain label reduces to 0, the label returns data to read immediately
Read device, complete once to communicate.Regardless of whether have label to respond, using the random changed power scope adjustment transmitting work(of reader
Rate.
Step 5, repeat step 3, until when frame slot number is kept to 0, this recognition cycle terminates.
During reader and label communication, reader adjusts transmission power using random changed power scope.Each
The changed power scope of reader is demarcated by the following method.
The radio frequency chip output of the RFID reader that the present embodiment is used can enter in the range of -19dB~0dB
Row is adjusted, radio frequency chip external power amplifier and antenna again.Experiment uses two readers and a label, two readers
Antenna and label are put on same level straight line, and wherein A readers are located at 0cm, and B readers are located at 240cm, and label is read positioned at two
Read between device antenna.
First, label is put at 60cm, " reading when the now reader of A, B two individually reads the label is measured respectively
Speed-output " characteristic curve；Label is put at 100cm again, the now reader of A, B two is measured respectively, and individually reading should
" reading rate-output " characteristic curve during label；Change label position is continued thereafter with, above-mentioned measurement is carried out, finally
The curve for arriving is as shown in Figure 3.
(derivative of i.e. this section curve is more than whole to choose the maximum scope of A curvilinear motions in each subgraph respectively from Fig. 3
The meansigma methodss of curve derivative), then the A reader maximum changing ranges under different label positions are averaged, it is defeated as A readers
Go out the change at random scope of power.Subsequently determine the output change at random scope of B readers by above-mentioned steps again.Finally set
The output constant interval for determining A readers is [- 11, -7] dB, and the output constant interval of B readers is [- 19, -4]
dB。
When Fig. 4 illustrates the present invention with constant power, the contrast of reader reading rate sum.As can be seen from Figure using this
Invention has a certain upgrade to the reading rate of reader.
According to experiment test, as shown in figure 4, (x, y) represents that A reader outputs take fixed value x (dB) and B reads in figure
Read device output take definite value y (dB), i.e. comparative reading device adopt the present invention with reader for constant power value when, reader reading
Take the situation of speed sum.
Darker curve is the reader reading rate sum of A, B two obtained using the present invention in figure, and lighter curve is read for A, B
Reading rate sum when reading device output is constant, it is known that lifted using the reader reading rate sum of the present invention.
Claims (1)
1. a kind of multichannel power change at random control method for RFID reader anticollision, it is characterised in that the method bag
Include step in detail below：
Step 1：Reader point channel
Reader randomly chooses channel；
Step 2：Random changed power scope is set
First, reader antenna and label are measured respectively same label and is existed with single reader on same level straight line
Under different distance, " reading rate-output " characteristic of reader is chosen the maximum scope of change from characteristic curve and i.e. should
The derivative of section curve is more than the meansigma methodss of whole curve derivative, then the excursion at different distance is averaged, and reads as this
Read the scope of the change at random of device output；Subsequently, the change at random of other reader outputs is determined in described manner
Scope；
Step 3：Reader reads label
（1）Reader sends Select command signals and selects population of tags, concurrently sets the initial frame length in the tag recognition cycle
I.e. timeslot number, starts the recognition cycle of this secondary label；
（2）Often complete the communication of READER-TO-TAG, regardless of whether there is label to respond, using reader output with
The scope adjustment transmission power of machine change；
（3）If frame slot is not 0, continue recognition cycle, reader continues to read label, until when frame slot number is kept to 0, this
Recognition cycle terminates.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201611223351.4A CN106682548A (en) | 2016-12-27 | 2016-12-27 | Multichannel power random change control method for RFID (radio frequency identification) reader collision preventing |
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| Application Number | Priority Date | Filing Date | Title |
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| CN201611223351.4A CN106682548A (en) | 2016-12-27 | 2016-12-27 | Multichannel power random change control method for RFID (radio frequency identification) reader collision preventing |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107451635A (en) * | 2017-08-25 | 2017-12-08 | 广东顺德中山大学卡内基梅隆大学国际联合研究院 | A kind of ultrahigh frequency RFID system |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101136053A (en) * | 2006-10-11 | 2008-03-05 | 中兴通讯股份有限公司 | Multiple labels anti-collision method used for radio frequency recognizing |
| CN102663328A (en) * | 2012-05-25 | 2012-09-12 | 中山大学 | Method for improving electron label reading efficiency based on power control |
| WO2012131461A1 (en) * | 2011-03-25 | 2012-10-04 | Leung Victor Chung Ming | Methods and apparatuses for the simultaneous detection of multiple radio frequency identification tags |
| CN103116734A (en) * | 2013-03-19 | 2013-05-22 | 天津工业大学 | Anti-collision method of RFID (Radio Frequency Identification) system based on power control |
| CN106096476A (en) * | 2016-06-06 | 2016-11-09 | 西北工业大学 | Based on multi channel reader collision avoidance method in a kind of rfid system |
-
2016
- 2016-12-27 CN CN201611223351.4A patent/CN106682548A/en not_active Withdrawn
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101136053A (en) * | 2006-10-11 | 2008-03-05 | 中兴通讯股份有限公司 | Multiple labels anti-collision method used for radio frequency recognizing |
| WO2012131461A1 (en) * | 2011-03-25 | 2012-10-04 | Leung Victor Chung Ming | Methods and apparatuses for the simultaneous detection of multiple radio frequency identification tags |
| CN102663328A (en) * | 2012-05-25 | 2012-09-12 | 中山大学 | Method for improving electron label reading efficiency based on power control |
| CN103116734A (en) * | 2013-03-19 | 2013-05-22 | 天津工业大学 | Anti-collision method of RFID (Radio Frequency Identification) system based on power control |
| CN106096476A (en) * | 2016-06-06 | 2016-11-09 | 西北工业大学 | Based on multi channel reader collision avoidance method in a kind of rfid system |
Non-Patent Citations (1)
| Title |
|---|
| 李雪等: "RFID系统多阅读器防碰撞问题研究", 《重庆交通大学学报(自然科学版)》 * |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107451635A (en) * | 2017-08-25 | 2017-12-08 | 广东顺德中山大学卡内基梅隆大学国际联合研究院 | A kind of ultrahigh frequency RFID system |
| CN107451635B (en) * | 2017-08-25 | 2020-06-05 | 广东顺德中山大学卡内基梅隆大学国际联合研究院 | Ultrahigh frequency RFID system |
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