TWI261787B - RFID device - Google Patents

RFID device Download PDF

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Publication number
TWI261787B
TWI261787B TW91134229A TW91134229A TWI261787B TW I261787 B TWI261787 B TW I261787B TW 91134229 A TW91134229 A TW 91134229A TW 91134229 A TW91134229 A TW 91134229A TW I261787 B TWI261787 B TW I261787B
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TW
Taiwan
Prior art keywords
time slot
signal
sensor
random
radio frequency
Prior art date
Application number
TW91134229A
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Chinese (zh)
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TW200300045A (en
Inventor
Mao-Song Chen
Chin-Te Ho
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Winbond Electronics Corp
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Priority to TW91134229A priority Critical patent/TWI261787B/en
Publication of TW200300045A publication Critical patent/TW200300045A/en
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Publication of TWI261787B publication Critical patent/TWI261787B/en

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    • GPHYSICS
    • G06COMPUTING; CALCULATING; COUNTING
    • G06KRECOGNITION OF DATA; PRESENTATION OF DATA; RECORD CARRIERS; HANDLING RECORD CARRIERS
    • G06K7/00Methods or arrangements for sensing record carriers, e.g. for reading patterns
    • G06K7/10Methods or arrangements for sensing record carriers, e.g. for reading patterns by electromagnetic radiation, e.g. optical sensing; by corpuscular radiation
    • G06K7/10009Methods 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
    • G06K7/10019Methods 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.
    • G06K7/10029Methods 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. the collision being resolved in the time domain, e.g. using binary tree search or RFID responses allocated to a random time slot
    • G06K7/10039Methods 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. the collision being resolved in the time domain, e.g. using binary tree search or RFID responses allocated to a random time slot interrogator driven, i.e. synchronous
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01SRADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S13/00Systems using the reflection or reradiation of radio waves, e.g. radar systems; Analogous systems using reflection or reradiation of waves whose nature or wavelength is irrelevant or unspecified
    • G01S13/74Systems using reradiation of radio waves, e.g. secondary radar systems; Analogous systems
    • G01S13/82Systems using reradiation of radio waves, e.g. secondary radar systems; Analogous systems wherein continuous-type signals are transmitted
    • GPHYSICS
    • G06COMPUTING; CALCULATING; COUNTING
    • G06KRECOGNITION OF DATA; PRESENTATION OF DATA; RECORD CARRIERS; HANDLING RECORD CARRIERS
    • G06K7/00Methods or arrangements for sensing record carriers, e.g. for reading patterns
    • G06K7/0008General problems related to the reading of electronic memory record carriers, independent of its reading method, e.g. power transfer

Abstract

A RFID (radio frequency identification) device, comprising a detector and several identification tags. The detector transmits a time slot cycle signal; each of time slot cycle of the signal has been divided into several slots. The identification tags are used to receive the time slot cycle signal, and each of the tags respectively contains a random generator to generate random numbers. Individual identification tag responds to the detector at assigned time slot corresponding to a random number generated by the random generator in each single time slot cycle.

Description

1261787 V. INSTRUCTION DESCRIPTION (T) 1. FIELD OF THE INVENTION The present invention relates to radio frequency identification devices, and more particularly to a radio frequency identification device that can identify tags having the same identification code. 2. [Prior Art] A Radio Frequency Identification eat tag (RF ID tag) is used to identify an application known to a user or a substance. In general, when the tag milk is 'modulated' and has an identification code (identifying the modulation (excited), the frequency of the magnetic field (magnef.CQde) may be generated in some cases. It is an electric field (electric Π le field), which is an active tag that contains a power supply itself, or is a dry, or . tag that can be read or placed in a sensor (for general purpose) When the passive range is within the range, the external excitation, such as the sense of the reader, is required. Generally speaking, when the passive tag approaches the sensing gate, the gate 'channel, etc. The emitted excitation frequency signal will produce a modulated residual = The transmitting antenna is then connected to the receiving antenna of the transmitting antenna to connect to the field or the electric field, and the sign is used to identify the label - 虼玲, and the label may further contain different identification semaphores < identiiication Code), It is used to distinguish between the products and the products. For example, the identification tags worn by the employees and the identification tags of the same kind are respectively implanted with different identification codes, so that they can be worn by each of them ("," use At the same time of sensing the door, according to the sensor, the identification of the % % Μ 使 126 126 126 126 126 126 126 126 126 126 126 126 126 126 126 126 126 126 126 126 126 126 126 126 126 126 126 126 126 126 126 126 126 126 126 126 126 126 The labels of different identification codes pass through the sensing range of the sensor. However, the sensor cannot recognize the number of labels with the same identification code in the sensing range at the same time. For example, the goods in the warehouse are labeled with labels for identification, different types. The goods labels have different identification codes, and the warehouse personnel use the sensors to scan the warehouse but only get the number of types of goods, but cannot know the quantity of each type in the warehouse. Therefore, it is necessary to improve the conventional wireless frequency identification. The system enables the sensor to detect the tag with the same identification code in the sensing range, and can instantly detect the change of the number of all the tags in the sensing range. [Invention] In view of the above invention background Many disadvantages caused by conventional radio frequency identification devices. The present invention provides a tag that can identify tags with the same identification code. Frequency identification device for overcoming conventionally derived problems - The main object of the present invention is to provide a radio frequency identification device that can identify tags having the same identification code. Another object of the present invention is to detect in real time in the sensing range. All labels

Page 6 1261787 V. Description of invention (3) Changes in quantity increase and decrease. Another object of the invention is to identify the number of tags having the same identification code.

According to the above, the present invention provides a radio frequency identification device comprising an inductor and a plurality of tags. The sensor is configured to emit a time slot period signal, and a time slot period in the time slot period signal is divided into a plurality of time slot positions. A plurality of tags are used to receive the time slot period signal, and the tags each include a random number generator to generate a random random number. The label is in the time slot period, and the signal is sent to the sensor at the time slot corresponding to the random number. The invention further discloses a method for identifying a tag having the same identification code in a radio frequency identification device, comprising the steps of: transmitting a continuous time slot period signal, wherein a time slot period is divided into a plurality of time slots. Detects all the tags in the sensor detection range, and the tag's reply message is in the different time slot position. Calculate the number of reply messages for all tags and compare them with the threshold to confirm the existence of the tag

Fourth Embodiment [Embodiment] A preferred embodiment of the present invention will be described in detail below. However, the present invention may be widely practiced in other embodiments, and the scope of the present invention is not limited by the detailed description, which is subject to the scope of the following patents.

Page 7 1261787 V. INSTRUCTION DESCRIPTION (4) The present invention provides a radio frequency identification device including an inductor and a plurality of tags. The sensor is configured to emit a time slot period signal, and a time slot period in the time slot period signal is divided into a plurality of time slot positions. A plurality of tags are used to receive the time slot periodic signal, and the tags each include a random number generator to generate a random random number. The label is in the time slot period, and the signal is sent to the sensor at the time slot position corresponding to the random random number. The invention further discloses a method for identifying a tag having the same identification code in a radio frequency identification device, comprising the steps of: transmitting a continuous time slot period signal, wherein a time slot period is divided into a plurality of time slots. Detects all the tags in the sensor detection range, and the tag's reply message is in the different time slot position. Calculating the number of reply messages for all tags and comparing them with the threshold value to confirm the presence of the tag. The first figure is a preferred embodiment of the radio frequency identification system of the present invention, wherein the reader generates a frequency of 1 3 The 5 6 MHz electromagnetic wave signal forms a sensing area or a debt measurement area within the signal transmission range. When the tag enters the sensor's full range, the tag receives the signal and synergizes and echoes the signal to the sensor. This reply signal carries the identification code (i d e n t i f i c a t i ο n c 〇 d e) held by the tag. When the sensor senses the reply signal of the tag, the different identification tags are used to identify different tags.

Page 8 1261787 V. Inventive Note (5) In addition, the tag generates a random IL number (r a n d 〇 m n u m b e r), and the tag determines which time slot (t i m e s 1 o t) to reply the signal to the sensor according to the random random number. Therefore, even if the tag with the same identification code exists in the detection range of the sensor at the same time, the sensor can receive the reply signal of the tag according to different time slots, thereby identifying the tag with the same identification code.

The second figure is a timing diagram for explaining the communication between the sensor and the labels A, B, and C in the first figure. The time slot period 2 1 0 (t i m e s 1 〇 t c y c 1 e ) is an electromagnetic wave of a frequency of 13.56 MHz generated by the above-mentioned inductor, or a scanning signal (s c a n s i g n a 1). The time slot period 2 1 0 is cut into 32 time slots, and the time slot is separated from the time slot by a silence signal 2 1 4 (mu te), and the time slot period is 2 1 0 and time. Between the slot periods 2 1 1 , four consecutive silencers are used as the time slot period interval 2 1 2 . The above-mentioned muffling signal 2 1 4 is a short pause of the sensor to emit the electromagnetic wave of 13.56 MHz, resulting in a so-called mute signal 2 1 4 .

When the standard enters the sensing range of the sensor, the antenna receives the electromagnetic wave of the 13.35 Μ Η z emitted by the sensor, and then the integrated power is used to become the working power supply for the tag. . However, in other embodiments, the tag may also use an external power source, such as a working power source that uses a battery to supply the tag.

The 9th page should be sent to the self-information sign to mark the mark back to this factor? The ancient mouth of the line Fan Jin should start to open the talent, should 11 2 yin bow y period Zhou Jin. Slot only h Φ» f ο When the period is 11 2 weeks, the waiting time is equal to 1261787. V. Description of the invention (6) One of the features of the present invention is that the tag includes a random random generator. In this embodiment, the random number generator is a co-oscillation circuit, and the oscillating circuit utilizes the uncertainty of the vibrator to continuously generate random random numbers, and the random random number does not exceed a time slot period. The number of time slots split. Furthermore, when the mark receives a time slot interval of 2 1 2, it starts counting to determine the position of the time slot. Therefore, as shown in the second figure, the random number generated by the label A is π 1 ", so when the label Α passes the time slot period interval 2 1 2, the message is returned to the sensor in the first time slot. Similarly, the number of chaos generated by the label B is π 3 ', so when the label Β passes the time slot period interval 2 1 2, the message is returned to the sensor in the third time slot. During the action period (acti ν atetime) 2 2 0 is the time when the tag occurs, and the length of time is equal to the length of one time slot. Except for the action period 2 2 0, the rest time is the stationary period (s 1 eeptime) 2 2 2, During the stationary period 2 2 2, in addition to counting, the tag will stop all actions until the corresponding time slot position appears. According to the above, since the tag is only allowed to operate during the action period 2 2 0, when the tag returns a message to the sensor, a new set of random numbers is simultaneously generated as the time slot position in the next time slot cycle. Therefore only

Page 10 1261787 V. INSTRUCTIONS (7) If the label persists within the sensing range of the sensor, a different random number will be generated in each time slot cycle, which also means that the tag is in each time slot cycle. Respond to the sensor at different time slot locations. However, since the generation range of the random number is limited to not exceed the number of time slots, for example, in the present embodiment, the time slot period 2 1 0 is divided into 32 time slots (times 1 〇t), so the range of random numbers is Between 1 and 3 2 . When there are a large number of tags in the sensing range, a tag with the same random number may appear, and a collision phenomenon in which the multi-tags reply to the sensor in the same time slot is generated (c ο 1 1 i s i ο η). Therefore, in other embodiments, the number of time slots is divided into time slots, which can be divided into more time slots according to actual application conditions, so as to reduce the occurrence of collisions. When a collision occurs, because multiple labels reply to the sensor at the same time, the signal overlaps, so the sensor cannot recognize which label the reply message replies when the collision occurs.

Page 11 1261787 V. INSTRUCTIONS (8) The third figure is used to illustrate the process block diagram of the sensor in the sensing range. First, the sensor emits a time slot period signal 300, which in this embodiment has 32 time slots in a time slot period. The tag within the sensor range generates a random number to determine the location of the time slot and to reply the message to the sensor. Therefore, the sensor senses the reply information 3 0 2 of the individual tags at different time slot positions in the time slot cycle. Under normal conditions, each tag has a different random number, so there is no collision. The sensor replies to the message according to the location of the different time slots to identify the tag with the same identification code. In addition, in order to resolve the unrecognizable caused by the collision, the sensor counts the number of times the tag replies to the message 3 0 4 . For example, the label A and the label B as shown in the second figure respectively have the identification code π Ο Ο Γ and the identification code "0 0 2 π, and the label C also has the identification code π 0 0 2 π. When the label A The reply signal of the label Β and the label C appears in different time slot positions in the time slot period. The sensor knows that the number of labels of the identification code π 0 0 1π is 1, and the number of labels of the identification code π 0 0 2 " 2, and use the counter to record the number of times. In the next time slot cycle, if there is no collision, the sensor will sense the presence of the label A, Β, C again, and add it to the label's count. When the count count exceeds the preset threshold (threshold), the sensor determines the existence of the label. For example, in this embodiment, the gate value is set to five times 'that is, when the standard A ' B ' C is specified Five consecutive achievements

Page 12 1261787 V. INSTRUCTIONS (9) There is no collision in the time slot cycle, so the count is up to five times. At this point, the sensor will confirm that the labels A, B, and C are indeed in the sensing range. Moreover, the count is limited to 10 times in this embodiment, and the count will not continue to be accumulated after the count reaches 10 times.

However, when the sensor fails to recognize the tag due to a collision phenomenon or because of noise, it starts counting down, as well as when the count is decremented below the threshold. The sensor sees that the tag below the count threshold is no longer in the range of the sensor. In addition, since the frequency of the continuous time slot period emitted by the sensor is extremely high, it takes only a short time for the sensor to confirm the number of tags with different identification codes in the sensing range. However, in the present embodiment, a single threshold value is used, and the manner in which the label is confirmed to exist is not the only embodiment. Other counting methods can also be used to confirm the existence of the label. Furthermore, the design of the threshold value can also be regarded as a balance of response time and reliability of the sensor.

Therefore, return to the sensor detection tag flow block diagram shown in the third figure. After step 3 0 4, the sensor determines the number of tags with different identification codes in the current sensing range according to the number of times the tag is counted, and according to this method, it can also be detected in the sensing range instantly, with different identification. The change of the code label and its quantity.

Page 13 1261787 V. INSTRUCTIONS (10) The above is only the preferred embodiment of the present invention and is not intended to limit the scope of the invention as claimed; Changes or modifications are to be included in the scope of the claims below. 1261787 BRIEF DESCRIPTION OF THE DRAWINGS FIG. 5 is a simplified illustration of the present invention. The first figure shows the radio frequency identification system of the present invention; the second figure is used to illustrate the timing diagram of the communication action between the sensor and the tag in the first figure; The third figure is used to illustrate the process block diagram of the sensor detection tag.

Representative symbols for the main part: 2 1 0 time slot cycle 21 1 time slot cycle 2 1 2 time slot cycle interval 2 1 4 silence signal 2 2 0 action period 2 2 2 stationary period

3 0 0 Sensor Detection Label Flow Block Step 3 0 2 Sensor Detection Label Flow Block Step 3 0 4 Sensor Detection Label Flow Block Step 30 6 Sensor Detection Label Flow Block Step

Page 15

Claims (1)

  1. 丨1 generation 6 W82 repair (more) original i case number 91134i29_year month 曰 correction _ six, application patent scope 1. A radio frequency identification device, comprising: a sensor for transmitting a time slot cycle signal, wherein the time A time slot period in the slot period signal is divided into a plurality of time slot positions; a plurality of labels are used to receive the time slot period signal, and respectively different time slot positions in the time slot period signal, and reply a message to the a sensor, wherein the message includes at least one tag identification code for identifying the tag; and a counter for calculating the number of times the plurality of tags are individually replied; wherein when the number of replies is higher than a preset threshold, This tag exists. 2. The radio frequency identification device according to claim 1, wherein the plurality of tags individually comprise a random number generator for generating a random random number, wherein the random random number is the label in the time slot cycle. The response signal is sent to the location of the sensor, wherein the range of the random random number does not exceed the number of time slots divided by the time slot period. 3. The radio frequency identification device according to claim 2, wherein the random number generator is a resonance circuit.
    4. The radio frequency identification device according to claim 2, wherein the random number generator generates a new random variable 0 5 in different time slot periods. The radio frequency identification as described in claim 1 Device, wherein
    Page 16 1261787 _ Case No. 91134229_年月日日_Amendment_ VI. Patent Application Range The above-mentioned time slot period signal is an electromagnetic wave signal 频率6 with a frequency of 13.5 6 MHz. As in the scope of claim 1 The radio frequency identification device, wherein in the time slot period, a silence signal is used to separate the time slot, and four consecutive silence signals are used to separate the time slot period. 7 - Radio frequency identification device ,contain:
    An inductor for transmitting a time slot period signal, wherein a time slot period of the time slot period signal is divided into a plurality of time slot positions; and a plurality of tags for receiving the time slot period signal, and the tag includes a random number generator for generating a random random number, wherein the label corresponds to the time slot position of the random random number in the time slot period, and replies a signal to the sensor, wherein the label is in a different time slot The cycle produces different random variables.
    8. The radio frequency identification device according to claim 7, wherein the range of the random random number does not exceed the number of time slots divided by the time slot period. 9. The radio frequency identification device of claim 7, wherein the method for detecting the plurality of tags by the sensor is as follows: transmitting a continuous time slot period signal, wherein a time slot period is divided into plural numbers Time slot
    Page 17 it 91131229,
    Six 'application patent scope i, detected in the - sensor detection range 'two: the back of the label 3 heart', where the reply message of the label is different; the slot is set on; calculate the solid of all the labels The message is overwritten and compared with a pre- and post-valuation value to confirm the existence of the tag. 1) As described in claim 7, the cheek recognition device, wherein the above time slot cycle is used a muffling signal for separating the time slot and using four consecutive silence signals for the interval slot period, the slot should be overwritten, and the b is used to sign the time. , the number of metrics is more than the reconsideration of the test, the signing should be sensitive to the frequency of the signing. It kind of <. Λ · step under the package containing Jtuu # 信期周槽间;器讯' In the signing, the last signing and the squad in the period of the splitting period are in the slot. , the time of the interest rate, the scope of the information, the verification of the return of the return of the return of the return of the return of the test and the setting of the value of the message 1 2 · as described in the scope of claim 11 The method of radio frequency identification of a tag, wherein the tag uses a random number generator to determine a time slot location for replying to the message. 1 3 The method of claim 12, wherein the label is different in different time slot cycles
    18th tribute ^126178 7 ^ ................. Case No. 911-34229 _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ The method of claim 12, wherein the time slot period signal is an electromagnetic wave signal having a frequency of 13.56 MHz. The method of claim 12, wherein the time slot period signal uses a silence signal,
    Used to separate time slots and use four consecutive silencers to separate time slot periods.
    Page 19 1261787 IV. Abstract of Chinese Invention (Name of Invention: Radio Frequency Identification Device) A radio frequency identification device comprising a sensor and a plurality of tags. The sensor is configured to emit a time slot period signal, and a time slot period in the time slot period signal is divided into a plurality of time slot positions. A plurality of labels are used to receive the time slot period 彳 § 5 tiger' and the labels each include a chaotic generator to generate random random numbers. It is hidden in the time slot period, and the signal is sent to the sensor at the time slot corresponding to the random number.
    Representative figure: second figure Component symbol: 2 1 0 time slot cycle 21 1 time slot cycle 2 1 2 time slot cycle interval English abstract (invention name: RFID DEVICE)
    A detector (radio frequency identification) device, including a detector and several identification tags. The detector transmits a time slot cycle signal·; each of time slot cycle of the signal has been divided into several slots. The identification tags are used to receive the Time slot cycle signal, and each of the tags respectively contains a random generator to generate random numbers. Individual identification tag responds to the detector at assigned time slot
    1261787
    Page 3
TW91134229A 2002-11-25 2002-11-25 RFID device TWI261787B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
TW91134229A TWI261787B (en) 2002-11-25 2002-11-25 RFID device

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
TW91134229A TWI261787B (en) 2002-11-25 2002-11-25 RFID device
DE2003152734 DE10352734A1 (en) 2002-11-25 2003-11-12 Radio frequency identification device
JP2003389046A JP4063758B2 (en) 2002-11-25 2003-11-19 Ultrasonic identification apparatus and method
GB0327196A GB2396781B (en) 2002-11-25 2003-11-21 Radio frequency identification device

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TW200300045A TW200300045A (en) 2003-05-01
TWI261787B true TWI261787B (en) 2006-09-11

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DE (1) DE10352734A1 (en)
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JP4514676B2 (en) * 2005-08-31 2010-07-28 富士通株式会社 Information access system
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TW200300045A (en) 2003-05-01
GB2396781A (en) 2004-06-30
GB2396781B (en) 2006-07-12
JP4063758B2 (en) 2008-03-19
GB0327196D0 (en) 2003-12-24
DE10352734A1 (en) 2004-07-01

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