GB2396781A - Selecting reply timeslots for RFID tag replies - Google Patents
Selecting reply timeslots for RFID tag replies Download PDFInfo
- Publication number
- GB2396781A GB2396781A GB0327196A GB0327196A GB2396781A GB 2396781 A GB2396781 A GB 2396781A GB 0327196 A GB0327196 A GB 0327196A GB 0327196 A GB0327196 A GB 0327196A GB 2396781 A GB2396781 A GB 2396781A
- Authority
- GB
- United Kingdom
- Prior art keywords
- time slot
- tags
- slot cycle
- detector
- tag
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
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Classifications
-
- G—PHYSICS
- G06—COMPUTING OR CALCULATING; 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.
- G06K7/10029—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. the collision being resolved in the time domain, e.g. using binary tree search or RFID responses allocated to a random time slot
- G06K7/10039—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. 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
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO 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
- G01S13/00—Systems 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
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO 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
- G01S13/00—Systems 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
- G01S13/74—Systems using reradiation of radio waves, e.g. secondary radar systems; Analogous systems
- G01S13/82—Systems using reradiation of radio waves, e.g. secondary radar systems; Analogous systems wherein continuous-type signals are transmitted
-
- G—PHYSICS
- G06—COMPUTING OR CALCULATING; 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
-
- G—PHYSICS
- G06—COMPUTING OR CALCULATING; 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
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B7/00—Radio transmission systems, i.e. using radiation field
- H04B7/24—Radio transmission systems, i.e. using radiation field for communication between two or more posts
- H04B7/26—Radio transmission systems, i.e. using radiation field for communication between two or more posts at least one of which is mobile
Landscapes
- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Remote Sensing (AREA)
- Radar, Positioning & Navigation (AREA)
- Computer Networks & Wireless Communication (AREA)
- Computer Vision & Pattern Recognition (AREA)
- Theoretical Computer Science (AREA)
- Artificial Intelligence (AREA)
- Health & Medical Sciences (AREA)
- Toxicology (AREA)
- Signal Processing (AREA)
- Electromagnetism (AREA)
- General Health & Medical Sciences (AREA)
- Near-Field Transmission Systems (AREA)
- Mobile Radio Communication Systems (AREA)
- Radar Systems Or Details Thereof (AREA)
Abstract
A radio frequency identification (RFID) system including a detector and several identification tags A, B, C, preferably for detecting tags having the same identification code. The detector transmits a signal having cycles 210, 211 that are each divided into a plurality of timeslots 1-32. The identification tags A, B, C, respond to each received cycle 210, 211 by transmitting a reply 220 in a selected timeslot of the cycle 210, 211. The selected time slot 220 is different in each cycle 210, 211. Each tag preferably contains a random generator to generate a random number which is used to select the reply timeslot. The random generator generates a new random number for each cycle; a different random number is generated for each cycle. By providing tag responses in different timeslots, tags having the same identification code can be identified. A method of confirming the existence of tags by detecting responses in different timeslots, counting the number of responses and comparing the number to a predetermined threshold is also claimed. Also discusses identifying the amount of tags with the same identification and detecting changes in the quantity of tags within the detection range of the detector.
Description
RADIO FP=QTvNCY 1D=NTIFlAllON DEVICE This invention generally relates to
the field of a radio frequency identification
(RFID) device. More particularly, the present invention relates to an RFID device to identify tags with the same identification code.
The use of RFID tags or cards to identify a person or an object is well known.
In general, such tags, when excited, produce a magnetic field, or in some cases an
electric field, of a first frequency, which is modulated with an identifying code. The
tag may be either an active tag, i.e., a tag, which has a self contained power supply or, as is more usually the case, may be a passive tag that requires external excitation when it is to be read or disposed within the detection volume of a reader, for example, a door À way or portal. In general, for portal type devices, passive type devices are utilized wherein a transmitting antenna for transmitting an exciting frequency signal for the tag is positioned at the portal and generally adjacent an antenna for receiving the modulated magnetic field, or electromagnetic field, produced by the excited tag in
order to identify the tag, and consequently the user or object attached thereto.
In addition, the RFID tags can include different identification codes to be used in distinguishing different objects. For example, using different identification codes in the tags for staffs and visitors makes users be identified by reading the identification codes from a reader while the users pass through the door way.
As mentioned above, the reader identifies either a single tag or tags with different identification codes passing through the detection range. However, the reader cannot simultaneously identify the quantity of tags with the same identification code in the detection range. For example, the goods in a warehouse have tags for identification, and different kinds of goods have tags with different identification codes. A storekeeper can only get the quantity of the categories by using the reader, but cannot get the quantity of each kind of goods.
Hence, there is a need for an improved RFID system that can identify the amount of tags with the same identification, as well as detect in time variance in the quantity of tags within the detection range.
According to the shortcomings mentioned in the background, the present
invention provides a radio frequency identification (RFID) device for identifying the tags with the same identification code to improve the foregoing drawback.
Accordingly, one of the objects of the present invention is to provide an RFID device for identifying the tags with the same identification code.
Another object is to detect the quantity changes of the tags in the detection range immediately.
Anosh-er object is to identify the quantity of the figs with the same identification code.
According to one aspect of the invention, there is provided a radio frequency identification (RFID) device, comprising: a detector transmitting a time slot cycle signal, wherein each of said time slot cycle signal is divided into several time slots; and a plurality of tags receiving said time slot cycle signal, and responding to said detector in different time slot in each of said time slot cycle signal.
According to a second aspect of the invention, there is provided a radio frequency identification (RFID) device, comprising: a detector transmitting a time slot cycle signal, wherein each of said time slot cycle signal is divided into several time slots; and a plurality of tags receiving said time slot cycle signal, and each of said plurality of tags respectively containing a random generator to generate a random number, wherein individual of said plurality of tags responds to said detector in assigned time slot corresponding to said random number in each of said time slot cycle signal, and said tag generates different random number in different time slot cycle. Thus using the invention it is possible to provide an
REID device including a detector and several identification tags. The detector transmits a time slot cycle signal, and each of the time slot cycle signal is divided into several time slots. The identification tags receive the time slot cycle signal, and each of the tags respectively contains a random generator to generate a random number. Individual identification tag responds to the detector in an assigned time slot corresponding to a random number generated by the random generator in each single time slot cycle.
The present invention further discloses a method to be used in the RFID device for identifying the tags with the same identification code, including: transmitting a continuous time slot cycle signal, wherein each of the time slot cycles is divided into several slots; detecting all responses from the tags in the detection range, wherein the responses are in different time slots; and counting all responses from the tags and comparing them with the threshold to confirm the existence of the tags.
The foregoing aspects and many of the attendant advantages of this invention will become more readily appreciated as the same becomes better understood by reference to the following detailed description, when taken in conjunction with the
accompanying drawings, wherein: FIG. 1 shows the presently inventive radio frequency identification system; FIG. 2 shows the communication timing between the detector and the tags in FIG. 1;
FIG. 3 shows the flow charts of the detector detecting the tags.
One of the preferred embodiments of the invention will now be described in greater detail. Nevertheless, it should be noted that the present invention can be practiced
s in a wide range of other embodiments besides those explicitly described, and the scope of the present invention is expressly not limited except as specified in the accompanying claims. 5 The present invention provides a radio frequency identification (RFID) device including a detector and several identification tags. The detector transmits a time slot cycle signal, and each of the cycle signals is divided into several slots. The identification tags receive the time slot cycle signal, and each of the tags respectively contains a random generator to generate a random number. Individual identification tag responds to 10 the detector in an assigned time slot corresponding to a random number generated by the random generator in each single time slot cycle.
The present invention filer discloses a method to be used in the RFID device for identifying the tags with the same identification code, including: transmitting a 15 continuous time slot cycle signal, wherein each of the time slot cycles is divided into several slots; detecting all responses from the tags in the detection range, wherein the responses are in different time slots; and counting all responses from the tags and comparing them with the threshold to confirm the existence of the tags.
20 FIG. 1 illustrates the preferred embodiment ofthe RFID system ofthe present invention. Electromagnetic wave signals at about frequency 13. 56MHz are generated by a detector. A detection range or volume is formed within the transmission region of the electromagnetic radio signals. While passage of a tag through the detection range, the tag receives the electromagnetic radio signals to generate resonance and sends a response
signal in response to the detector. The response signal includes the identification code of the tag. The detector identifies different tags according to the different identification codes while the detector receives the responses from tags.
5 Besides, the tag generates a random number and responds a response signal in the corresponding time slot according to the random number. By doing so, the detector can identify the tags with the same identification code according to the response signals of the tags in different time slots although there are many tags with the same identification code in the detection range at the same time.
FIG. 2 illustrates communication timings between the detector and the Tags, A, B and C, in FIG. 1. A time slot cycle 210 is a 13.56MHz of electromagnetic wave or a so-called scan signal generated by the detector. The time slot cycle 210 is divided into 32 time slots, and uses a mute signal 214 as an interval between these time slots. As to the 15 interval between the time slot cycle 210 and 220, four continuous mute signals are used as the time slot cycle interval 212. The mute signal 214 is a result of temporary interruption of the electromagnetic radio signals from the detector.
The tag in resonance through rectification provides a work power for the tag.
20 However, the work power for the tag in other embodiments can use an exterior power such as batteries.
One characteristic of the present invention is that the tag contains a random generator. In accordance with the embodiment, the random generator is a resonance
circuit, and continuously generates a random number by applying the uncertainty of an oscillator, wherein the range of the random number cannot exceed the number of time slots in a time slot cycle, and the tag starts to count for confirming the time slot after receiving the time slot cycle interval 2 l 2.
As shown in FIG. 2, the Tag A generates a random number "1", thus the Tag A responds to the detector in the first time slot after the time slot cycle interval 212.
Similarly, the Tag B generates a random number "3", thus the Tag B responds to the detector in the third time slot after the time slot cycle interval 212. The activation time 10 220 is a period that the tag activates during and about equal to a time slot. The rest ofthe exclusive activation time 220 is sleeping time 222. The tag stops any activities except counting in the sleeping time 222 until the corresponding time slot appears.
The Tag C joins the detection range in the middle of the time slot cycle 210, 15 thus the Tag C cannot count and respond to the detector until next time slot cycle 211.
As mentioned above, the tag is allowed to activate only in the activation time 220, hence the tag simultaneously generates a new random number to assign the time slot in next time slot cycle while the tag responds to the detector. Therefore, the tag 20 generates different random number in each time slot cycle while the tag still stays in the detection range. This is, the tag responds to the detector in different time slot in each time slot cycle.
However, the range of the random number is restricted within the number of
time slots. For example, the time slot cycle 210 is divided into 32 time slots in the embodiment hence the range of the random number should be between 1 and 32. While there are many tags in the detection range, the tags with the same random number may occur. This situation causes many tags responding to the detector in the same time slot 5 and leads to a collision. Therefore, in other embodiments, the number of the divided time slot can depend on the practical needs, and the collision can be reduced by dividing the time slot cycle into more time slots.
Moreover, while the collision occurs, the responses from many tags result in 10 chaotic responses, and the detector cannot classify the response from tags.
As shown in FIG. 2, the message of the tag responding to the detector includes a preamble, a header, an ID, a checksum, and a tail. Thus, the random number generated by the random generator is included in the ID field. However, the message
15 format is not just limited in the format mentioned above, but can be adjusted to adapt to different applications.
FIG. 3 illustrates the flow charts of the detector detecting the tags in the detection range. The detector transmits a time slot cycle signal 300, and the time slot 20 cycle has 32 time slots in the embodiment. The tag in the detection range generates a random number to assign a corresponding time slot to respond to the detector. Hence, the detector receives the individual tag response message 302 in a different time slot in the time slot cycle. Normally, a collision cannot occur since the random numbers of the tags are different. The detector identifies the tags with the same identification code according
to the response message in the different time slots.
Besides, for solving the unidentified problelmult llulll the collision, the detector counts the number of times 304 of the tag response message. For example, as 5 shown in FIG. 2, the Tag A and Tag B respectively has identification code "001" and "002", and the Tag C also has the same identification code "002". While the response messages of Tag A, Tag B. and Tag C are in the different time slots in the time slot cycle, the detector detects the number of tags and records the number of times. For example, one tag has the identification code "O01" and two tags have the identification code "O02".
10 If there is no collision in the next time slot cycle, the detector will detect the Tag A, Tag B. and Tag C again and respectively add one to their number of times. The detector will confirm the existence of the tag while the numbers of times of the tag exceed a predetermined threshold. For example, the predetermined threshold in the embodiment is five. This is, while the Tag A, Tag B. and Tag C have no collisions during five 15 continuous time slot cycles, the detector will just confirm the existence of Tag A, Tag B. and Tag C in the detection range. Furthermore, the maximum limit in the embodiment is ten, and the number of times will not be accumulated while it exceeds ten.
The detector will decrease the number of times by degrees while the collision 20 or noise results in the unidentified situation. Similarly, while the number of times of the tag is lower than the predetermined threshold, the detector will not confirm the existence ofthe tag in the detection range. Besides, the frequency ofthe continuous time slot cycle is very high, and hence the detector can confirm the number oftags in the detection range during a short time.
However, using the single threshold in the embodiment for confirming the existence of the tag is not the only applied method. Other counting methods can also be applied to confirm the existence of the tag. Furthermore, the threshold designed can 5 depend on both response time and reliability of the detector.
As shown in FIG. 3, after the step 304 and according to the number of times of the tags counted, the detector confirms the number of tags 306 with different identification codes in the detection range. By doing so, the tags with different 10 identification codes and the numbers changed in the detection range can be simultaneously detected.
Although specific embodiments have been illustrated and described, it will be obvious to those skilled in the art that various modifications may be made without 15 departing from what is intended to be limited solely by the appended claims.
Claims (17)
1. A radio frequency identification (RFID) device, comprising: a detector transmitting a time slot cycle signal wherein each of said time slot cycle signal is divided into several time slots; and 5 a plurality of tags receiving said time slot cycle signal, and responding to said detector in different time slot in each of said time slot cycle signal.
2. The RFID device according to claim 1, wherein each of said plurality oftags respectively contains a random generator to generate a random number, and responds to said detector in assigned time slot corresponding to said random number in each said 10 single time slot cycle signal, wherein the range of said random number cannot exceed the number of said time slots.
3. The RFID device according to claim 2, wherein said random generator is a resonance circuit.
I
4. The RFID device according to claim 2 or claim 3, wherein said random generator generates a new random number in each of said time slot cycle signal.
5. The RFID device according to any preceding claim, wherein said time slot cycle signal is a 1 3.56MHz of electromagnetic wave.
6. The RFID device according to any preceding claim, wherein a mute signal is used as an interval between said time slots, and four continuous mute signals are used as an interval between said time slot cycles.
7. A radio frequency identification (RFID) device, comprising: a detector transmitting a time slot cycle signal, wherein each of said time slot cycle signal is divided into several time slots; and
a plurality of tags receiving said time slot cycle signal, and each of said plurality of tags respectively containing a random generator to generate a random number, wherein individual of said plurality of tags responds to said detector in assigr ed time slot corresponding to said random number in each of said time slot cycle signal, and 5 said tag generates different random number in different time slot cycle.
8. The RFID device according to claim 7, wherein the range of said random number cannot exceed the number of said time slots.
9. The RFID device according to claim 7 or claim 8, wherein steps of said detector detecting said plurality of tags, comprise 10 transmitting a continuous time slot cycle signal, wherein each of said time slot cycle is divided into several time slots; detecting all responses form said tags in the detection range, wherein said responses are in different time slots; and counting the number of responses from said tags and comparing with a 15 Predetermined threshold to confirm the existence of said tags.
10. The RFID device according to any of claims 7 to 9, wherein a mute signal is used as an interval between said time slots, and four continuous mute signals are used as an interval between said time slot cycles.
11. A method for a detector identifying tags with the same identification code 20 in a radio frequency identification (RFID) device, comprising: transmitting a continuous time slot cycle signal, wherein each of said time slot cycle is divided into several time slots; detecting all responses form tags in the detection range, wherein said responses are in different time slots; and
À counting the number of responses from said tags and comparing with a predetermined threshold to confirm the existence of said tags.
12. The method according to claim 11, wherein said tag uses a random generator to decide the time slot of said response.
13. The method according to claim 11 or claim 12, wherein said tag responds to said detector in different time slot in each time slot cycle.
14. The method according to any of claims 11 to 13, wherein said time slot cycle signal is a 1 3.56MHz of electromagnetic wave.
15. The method according to any of claims 11 to 14, wherein a mute signal is used as an interval between said time slots, and four continuous mute signals are used as an interval between said time slot cycles.
16. A radio frequency identification (REID) device, substantially as hereinbefore described with reference to the accompanying drawings.
17. A method for a detector identifying tags with the same identification code in a radio frequency identification (RFID) device, substantially as hereinbefore described with reference to the accompanying drawings.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| TW091134229A TWI261787B (en) | 2002-11-25 | 2002-11-25 | RFID device |
Publications (3)
| Publication Number | Publication Date |
|---|---|
| GB0327196D0 GB0327196D0 (en) | 2003-12-24 |
| GB2396781A true GB2396781A (en) | 2004-06-30 |
| GB2396781B GB2396781B (en) | 2006-07-12 |
Family
ID=29778267
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB0327196A Expired - Lifetime GB2396781B (en) | 2002-11-25 | 2003-11-21 | Radio frequency identification device |
Country Status (4)
| Country | Link |
|---|---|
| JP (1) | JP4063758B2 (en) |
| DE (1) | DE10352734A1 (en) |
| GB (1) | GB2396781B (en) |
| TW (1) | TWI261787B (en) |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101751538B (en) * | 2008-12-01 | 2012-03-28 | 中兴通讯股份有限公司 | RF recognition label distributing method and device thereof |
| US10922939B1 (en) | 2019-04-11 | 2021-02-16 | Nexite Ltd. | Information management system for tagged goods |
| US11508225B2 (en) | 2021-01-11 | 2022-11-22 | Nexite Ltd. | Theft prevention for returned merchandise |
| US11551537B2 (en) | 2019-04-11 | 2023-01-10 | Nexite Ltd. | Wireless dual-mode identification tag |
| US11797928B2 (en) | 2021-12-13 | 2023-10-24 | Nexite Ltd. | Dual-antenna, four-armed identification tag |
Families Citing this family (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP1717963B1 (en) * | 2005-04-25 | 2010-04-14 | Sony Ericsson Mobile Communications AB | Electronic equipment for a wireless communication system and method for operating an electronic equipment for a wireless communication system |
| US20080258864A1 (en) * | 2004-10-28 | 2008-10-23 | Mitsubishi Electeic Corporation | Communication Apparatus and Communication Method |
| JP4514676B2 (en) * | 2005-08-31 | 2010-07-28 | 富士通株式会社 | Information access system |
| KR100848639B1 (en) | 2007-05-15 | 2008-07-28 | 에스케이 텔레콤주식회사 | Apparatus for determining the number of time slots in the RFID system, tag recognition method using the same, system |
| KR100948049B1 (en) | 2007-11-01 | 2010-03-19 | 주식회사 메디슨 | Ultrasound diagnostic management system |
| US8031069B2 (en) | 2008-01-14 | 2011-10-04 | Oded Yair Cohn | Electronic security seal and system |
| TWI645338B (en) * | 2017-10-26 | 2018-12-21 | 茂德科技股份有限公司 | An operation method of radio frequency identification reader |
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2002
- 2002-11-25 TW TW091134229A patent/TWI261787B/en not_active IP Right Cessation
-
2003
- 2003-11-12 DE DE10352734A patent/DE10352734A1/en not_active Ceased
- 2003-11-19 JP JP2003389046A patent/JP4063758B2/en not_active Expired - Fee Related
- 2003-11-21 GB GB0327196A patent/GB2396781B/en not_active Expired - Lifetime
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Cited By (23)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101751538B (en) * | 2008-12-01 | 2012-03-28 | 中兴通讯股份有限公司 | RF recognition label distributing method and device thereof |
| US11288939B2 (en) | 2019-04-11 | 2022-03-29 | Nexite Ltd. | Wireless device for ambient energy harvesting |
| US11295592B2 (en) | 2019-04-11 | 2022-04-05 | Nexite Ltd. | Identification tag configured for variable intervals between signal transmissions |
| US10991220B2 (en) | 2019-04-11 | 2021-04-27 | Nexite Ltd. | Wireless dual-mode identification tag |
| US10997840B2 (en) | 2019-04-11 | 2021-05-04 | Nexite Ltd. | System for simultaneous tag triggering and sequential tag reading |
| US11107336B2 (en) | 2019-04-11 | 2021-08-31 | Nexite Ltd. | Wireless device configured for powering transmissions with harvested energy |
| US11138851B2 (en) | 2019-04-11 | 2021-10-05 | Nexite Ltd. | Capacitor architecture for wireless communication tag |
| US11170620B2 (en) | 2019-04-11 | 2021-11-09 | Nexite Ltd. | Wireless dual-mode identification tag |
| US11217077B2 (en) | 2019-04-11 | 2022-01-04 | Nexite Ltd. | Appliances with integrated communication tags |
| US11238714B2 (en) | 2019-04-11 | 2022-02-01 | Nexite Ltd. | Privacy system for electronically tagged goods |
| US11341828B2 (en) | 2019-04-11 | 2022-05-24 | Nexite Ltd. | Wireless identification tag with varying identity |
| US10930128B2 (en) | 2019-04-11 | 2021-02-23 | Nexite Ltd. | System configured for spoofing avoidance |
| US11288940B2 (en) | 2019-04-11 | 2022-03-29 | Nexite Ltd. | Tag configured for interaction with security gate |
| US10922939B1 (en) | 2019-04-11 | 2021-02-16 | Nexite Ltd. | Information management system for tagged goods |
| US11398144B2 (en) | 2019-04-11 | 2022-07-26 | Nexite Ltd. | Identification tag with variable response time |
| US11551537B2 (en) | 2019-04-11 | 2023-01-10 | Nexite Ltd. | Wireless dual-mode identification tag |
| US11508225B2 (en) | 2021-01-11 | 2022-11-22 | Nexite Ltd. | Theft prevention for returned merchandise |
| US11763651B2 (en) | 2021-01-11 | 2023-09-19 | Nexite Ltd. | Contactless security for a retail store |
| US11995966B2 (en) | 2021-01-11 | 2024-05-28 | Nexite Ltd. | Systems and methods for verifying remote purchases |
| US12307868B2 (en) | 2021-01-11 | 2025-05-20 | Nexite Ltd. | Systems and methods for automatic planogram generation |
| US12417686B2 (en) | 2021-01-11 | 2025-09-16 | Nexite Ltd. | Automatic product inventory management for retail store |
| US11797928B2 (en) | 2021-12-13 | 2023-10-24 | Nexite Ltd. | Dual-antenna, four-armed identification tag |
| US12014326B2 (en) | 2021-12-13 | 2024-06-18 | Nexite Ltd. | Systems and methods for mobile self-checkout of wireless tagged products |
Also Published As
| Publication number | Publication date |
|---|---|
| JP2004180300A (en) | 2004-06-24 |
| GB0327196D0 (en) | 2003-12-24 |
| TWI261787B (en) | 2006-09-11 |
| GB2396781B (en) | 2006-07-12 |
| JP4063758B2 (en) | 2008-03-19 |
| DE10352734A1 (en) | 2004-07-01 |
| TW200300045A (en) | 2003-05-01 |
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| Date | Code | Title | Description |
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| PE20 | Patent expired after termination of 20 years |
Expiry date: 20231120 |