Performance convergence of radio frequency identification device in electronic commodity anti-theft system

Abstract

A radio frequency identification device for an electronic article surveillance ("EAS") system may have different configurations such that performance varies in an operating frequency or frequency range of the electronic article surveillance system. The performance of the radio frequency identification devices with different configurations can tend to be consistent or basically similar in performance by testing the performance of the radio frequency identification devices in the frequency range. And if the performance of the radio frequency identification devices is not similar enough, at least one radio frequency identification device is reconfigured to enable the performance of the radio frequency identification devices to tend to be consistent in the frequency range. This may include changing the configuration of the non-functional components of the antenna, the radio frequency identification chip and / or the radio frequency identification device and / or the location of the radio frequency identification device associated with the item. The production initial configurations of the radio frequency identification devices with different configurations can be the same, and different radio frequency identification devices are processed differently before being integrated into the electronic commodity anti-theft system.

Description

[0001] This case is a divisional application of a case with an application date of February 25, 2021, an invention name of Performance Convergence of Radio Frequency Identification Devices in Electronic Article Anti-theft Systems, and an application number of 2021800293710.

[0002] Cross-references to related patent applications

[0003] This application claims the benefit of U.S. Provisional Patent Application No. 62 / 981,211 filed on February 25, 2020, which is incorporated herein by reference in its entirety and becomes a part of the present invention. Technical Field

[0004] The present subject matter relates to radio frequency identification ("RFID") devices. More particularly, the present subject matter relates to harmonizing the performance of differently configured RFID devices for electronic article surveillance ("EAS") systems. Background Art

[0005] In retail stores, it is very important to accurately count the products on display and / or in storage. In addition, it is also very important to establish an effective anti-theft system. Radio frequency identification tags (collectively referred to herein as "RFID devices") are often used to achieve both functions.

[0006] Electronic article surveillance systems that use RFID technology typically have two main read zones, each with an associated RFID reader. One of the read zones is the area of ​​the store where products are displayed to consumers (which may be referred to as the "inventory zone" in this disclosure), and the other read zone is the store exit area, where any RFID device that has not been properly deactivated can be detected (which may be referred to as the "detection zone" in this disclosure) to trigger some type of alarm, indicating that someone is attempting to steal the goods. When the customer properly purchases the goods, the cashier removes or deactivates the RFID device associated with the goods. If the RFID device has not been removed or deactivated, the RFID reader will read the device and trigger an alarm or other alarm in the detection zone.

[0007] Although the above systems are widely used, some disadvantages still exist. When using RFID devices / systems for electronic article surveillance systems, a common problem is that in some cases, the read range of the RFID device may be large enough that an RFID device in the inventory area can be read in the detection area, and vice versa. To reduce this risk, a transition zone is often provided between the inventory area and the detection area to physically separate the two reading zones. However, since different RFID devices have higher sensitivity at the operating frequency and / or different items have different effects on the performance of the associated RFID device, the transition zone must be relatively large. The larger the transition zone, the smaller the inventory area, and therefore the fewer items that the retailer can display. Therefore, it would be advantageous to provide a system in which RFID devices of different configurations perform the same at the operating frequency or frequency range of the electronic article surveillance system, thereby reducing the size of the transition zone. Summary of the invention

[0008] Several aspects of the subject matter are described and claimed below, which may be included in the devices, systems, and methods alone or together. These aspects may be used alone or in combination with other aspects of the subject matter described herein, and the description of these aspects is not intended to exclude the use of these aspects alone or to state the use of these aspects alone or in different combinations that may be listed in the claims appended to the present invention.

[0009] The present invention describes a method for configuring a radio frequency identification device for an electronic article surveillance system. In some embodiments, the method includes: step 1, providing a plurality of sample radio frequency identification devices of different configurations (tagged to different products monitored by the electronic article surveillance system); step 2, testing the performance of the plurality of sample radio frequency identification devices of different configurations within a frequency range; step 3, comparing the performance of the sample radio frequency identification devices within the frequency range with the performance of a plurality of target radio frequency identification devices within the frequency range; and step 4, when the performance of one or more radio frequency identification devices within the frequency range is not similar enough to the performance of complementary target radio frequency identification devices within the same frequency range, reconfiguring at least one or more of the plurality of sample radio frequency identification devices of different configurations so that the performance of the one or more radio frequency identification devices within the frequency range is consistent. Reconfiguring at least one or more of the plurality of sample radio frequency identification devices of different configurations so that the one or more sample radio frequency identification devices within the frequency range are consistent may include digitally reconfiguring the device, physically reconfiguring the device, or a combination thereof. The method of digitally and physically reconfiguring the device is described in detail below.

[0010] The performance configuration of multiple target RFID devices is selected in such a way that after reconfiguration, the performance of each of the multiple differently configured sample RFID devices is similar, even though the devices may be labeled as different goods / products. When the one or more sample RFID devices are sufficiently similar within the frequency range, the reconfigured one or more sample RFID devices are integrated into the electronic article anti-theft system. Similarly, other sample RFID devices of the multiple RFID devices are tested and compared with the performance of complementary target RFID devices and ultimately integrated into the electronic article anti-theft system. When all sample RFID devices work the same due to convergence in performance, the electronic article anti-theft system becomes more predictable. This helps optimize the system to achieve good monitoring in the detection zone (door) of the electronic article anti-theft system.

[0011] In some embodiments, the reconfiguration of the one or more sample RFID devices can be achieved by digitally modifying the one or more sample RFID devices. In some embodiments, the digital modification involves providing each of the one or more sample RFID devices with a unique digital indicator, which is connected to a digital database containing performance configuration information of multiple target RFID devices (including performance configuration information of complementary target RFID devices corresponding to the one or more sample RFID devices). In some embodiments, when the one or more sample RFID devices are marked as a group of products of the same type, the unique digital indicators are the same. In addition, the performance configuration information of the multiple target RFID devices (including the performance of the complementary target RFID devices) is determined according to the product type of the corresponding multiple sample RFID devices marked.

[0012] In some embodiments, the reconfiguration of the one or more sample RFID devices is achieved by physically modifying the one or more sample RFID devices so that the performance of the one or more sample RFID devices tends to be consistent. In some embodiments, the physical modification includes but is not limited to changing the antenna configuration, changing the antenna size, changing the antenna material composition, etc. and combinations thereof.

[0013] In some embodiments, the reconfigured sample RFID devices are integrated into an electronic article surveillance system. The electronic article surveillance system further includes an RFID reader for reading the one or more sample RFID devices, each sample RFID device including a unique digital indicator based on the performance configuration information of the one or more sample RFID devices (obtained from a digital database). This enables the electronic article surveillance system (including the RFID reader of the detection zone) to digitally consider the behavior of all sample RFID devices, so that the reader of the detection zone sounds an alarm when any product is stolen. At the same time, it ensures that no false alarms are generated due to excessive reading.

[0014] In some embodiments, the present invention also describes a method for producing an RFID device for an electronic article surveillance system. The method includes providing a plurality of sample RFID devices having the same initial configuration, and when the performance of one or more sample RFID devices is different from the performance of a complementary target RFID device and / or is different from each other, reconfiguring one of the plurality of sample RFID devices to have a first final configuration, and reconfiguring another of the plurality of sample RFID devices to have a second final configuration. The sample RFID devices having the first final configuration and the second final configuration are then integrated into an electronic article surveillance (EAS) system, wherein the first final configuration is different from the second final configuration. The performance of the sample RFID devices having the first final configuration and the second final configuration used in the electronic article surveillance system is sufficiently similar in frequency or frequency range.

[0015] In some embodiments, at least one of the first final configuration and the second final configuration of the sample RFID device has an antenna with a different size than the antenna of the initial configuration.

[0016] In some embodiments, the antenna shape of at least one of the first final configuration and the second final configuration of the sample RFID device is different from the antenna of the initial configuration.

[0017] In some embodiments, at least one of the first final configuration and the second final configuration includes an overprinted resistive material, an overprinted dielectric material, an overprinted conductive material, or an overprinted magnetic material that is not included in the initial configuration. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 is a schematic diagram of the first sample RFID device and a graph of its performance over a range of frequencies.

[0019] Figure 2 is a schematic diagram of the second sample RFID device and its Figure 1 Performance graph for the same frequency range.

[0020] Figure 3 yes Figure 1 and Figure 2 Schematic diagram of a reconfigured version of the sample RFID device and its Figure 1 and Figure 2 Performance graph for the same frequency range. DETAILED DESCRIPTION

[0021] Specific embodiments of the present invention are disclosed herein; however, it should be understood that the disclosed embodiments are only exemplary of the present invention, which can be embodied in various forms. Therefore, the specific details disclosed in the present invention are not to be interpreted as limiting, but merely as a basis for the claims and as a representative basis for teaching one skilled in the art to use the present invention in almost any appropriate manner.

[0022] RFID devices of different sizes, materials, and / or configurations may have different combinations of parameters, so if an electronic article surveillance system is optimized to reduce the transition zone size of one RFID device, it may not be effective for RFID devices of different configurations. Although it is practical to make all RFID devices used in an electronic article surveillance system behave the same, different configurations of goods will also have different effects on the performance of the associated RFID devices. Therefore, when attempting to reduce the transition zone size of an electronic article surveillance system so that the system accommodates RFID devices of different configurations and goods of different configurations, various factors must be considered.

[0023] In some embodiments, two differently configured RFID devices (or two similarly configured RFID devices associated with different goods / products or the same type of goods / products at different locations) are tested within a frequency range. Figure 1 A first sample RFID device 10 of a plurality of sample RFID devices of different configurations (not shown) and its performance over a frequency range are shown. It should be understood that the exact criteria encompassed by the term "performance" may vary without departing from the scope of the present invention, but may include the sensitivity of the first sample RFID device 10. Likewise, the nature of the tests performed on the first sample RFID device 10 to determine performance over a frequency range may vary, depending on the relevant standard (i.e., the standard used to define the "performance" of the first sample RFID device 10). If multiple tests are performed on the first sample RFID device 10 over a frequency range, different weights are given to the results of at least two tests depending on the relative importance of the different values ​​being tested. The plurality of sample RFID devices of different configurations (including the first sample RFID device mentioned in the present invention) are RFID devices to be integrated into an electronic article theft prevention system.

[0024] It should be understood that the specific frequency ranges in which the performance of the RFID device is considered may vary without departing from the scope of the present invention. However, it may be advantageous for the frequency ranges to be the same frequency ranges or to include operating frequencies used in the electronic article surveillance system in which the RFID device is to be integrated. If possible, it may be advantageous to consider the performance of the RFID device in the context of the exact electronic article surveillance system in which the RFID device is to be integrated. If not possible, it may be advantageous to consider the performance of the RFID device in an environment that simulates the electronic article surveillance system in which the RFID device is to be integrated.

[0025] Figure 2 A second sample RFID device 12 of the plurality of sample RFID devices (not shown) in different configurations and its use with Figure 1 Performance within the same frequency range. Based on the overall performance of the RFID device in the electronic article theft surveillance system, the multiple sample RFID devices of different configurations are reconfigured or integrated into the electronic article theft surveillance system in their original configuration. When all sample RFID devices tagged to various products and monitored by the electronic article theft surveillance system work the same, the electronic article theft surveillance system becomes predictable, which helps optimize the system for good detection in the detection zone while preventing false alarms in the detection zone. Therefore, it becomes necessary to converge the performance of the multiple sample RFID devices of different configurations configured to be placed in the inventory area. By making the read range of all sample RFID devices in the inventory area consistent and controlling the variability of the sample RFID devices in the inventory area, the inventory area and the detection zone of the electronic article theft surveillance system can be better controlled.

[0026] In some embodiments, multiple target RFID devices are provided as references for performance comparison and convergence. For example, the performance of the multiple differently configured sample RFID devices may converge with the performance of the complementary target RFID device corresponding to each of the multiple differently configured sample RFID devices. According to one aspect of the present invention, the target RFID device is selected so that the performance of the sample RFID device converges with the performance of the complementary target RFID device, thereby making the performance of all differently configured sample RFID devices converge as a whole. In one embodiment, the multiple differently configured sample RFID devices marked to different products and having different read ranges are reconfigured so that the read ranges of the multiple differently configured sample RFID devices within the frequency range are the same, thereby generating performance convergence. The convergence of performance is to ensure that the performance of all sample RFID devices is similar, even if the devices are fixed to different goods / products made of different materials. In one embodiment, the performance of the multiple differently configured sample RFID devices may converge with a single target RFID device. In another embodiment, the performance of one or more RFID devices of the multiple differently configured sample RFID devices may converge with the performance of the complementary target RFID device. The performance configuration information corresponding to the plurality of target devices is stored in an accessible digital database for accomplishing performance convergence. In determining the performance configuration information of the plurality of target RFID devices, the nature of the goods / products to be marked by the plurality of differently configured sample RFID devices is considered.

[0027] Typically, the configuration of the second sample RFID device 12 differs from the configuration of the first sample RFID device 10, which may include one or more differences in antenna configuration (including shape, size, and material composition); configuration of the RFID chip (including sensitivity, input capacitance, and identifier); nature and configuration of related non-functional components; nature of related goods / products; and location where the device is connected to the related goods. It should be understood that the above-listed items are only used as examples, and there may be other differences between the first sample RFID device 10 and the second sample RFID device 12.

[0028] By comparison Figure 1 and Figure 2 It can be seen that the sample RFID devices 10 and 12 have different performances within the same frequency range. Due to the performance differences (and assuming that the frequency range represents the operating frequency or frequency range used in the electronic article surveillance system into which the RFID devices 10 and 12 will be integrated), the electronic article surveillance system into which the RFID devices 10 and 12 are integrated may require a relatively large transition zone to prevent false alarms.

[0029] In some embodiments, one or more of the plurality of differently configured sample RFID devices may be reconfigured (by the digital means and / or physical means described above) to ensure that the transition zone of the electronic article surveillance system is relatively small. For example, in an embodiment of the present invention, the first and second sample RFID devices 10 and 12 are reconfigured so that their performances tend to be consistent (i.e., their performances are more similar) within the tested frequency range. Figure 3 A reconfigured version 10' of the first sample RFID device 10, a reconfigured version 12' of the second sample RFID device 12, and two reconfigured first and second sample RFID devices 10' and 12' are shown. Figure 1 and Figure 2 The performance comparison within the same frequency range is shown in which the solid line represents the performance of the first reconfigured sample RFID device 10' and the dashed line represents the performance of the second reconfigured sample RFID device 12'. Figure 3 As shown, the performance of the two reconfigured first and second sample RFID devices 10' and 12' is different in the frequency range, but very similar, and significantly better than Figure 1 and Figure 2 Therefore, it can be said that the performance of the original first and second sample RFID devices 10 and 12 over the frequency range has been brought into line with each other through the reconfiguration.

[0030] In some embodiments, to bring the performance of the plurality of differently configured sample RFID devices closer to consistency, the sample RFID devices are reconfigured by testing and comparing the sample RFID devices individually and modifying each sample RFID device. In another embodiment, to bring the performance of the plurality of differently configured sample RFID devices closer to consistency, the reconfiguration may include testing and then comparing with complementary target RFID devices, and modifying each of the plurality of differently configured sample RFID devices according to the performance configuration of each complementary target RFID device. The performance configuration of the plurality of target RFID devices is selected in such a way that, after reconfiguration, the performance of each of the plurality of differently configured sample RFID devices is similar, even though the devices may be labeled as different goods / products.

[0031] In some embodiments, the reconfiguration of the plurality of differently configured sample RFID devices involves digitally modifying one or more sample RFID devices having different performance configurations. The digital modification includes, but is not limited to, providing each of the one or more sample RIFD devices with a unique digital indicator, the digital indicator being connected to a digital database containing performance configuration information of a plurality of target RFID devices (including performance configuration information of complementary target RFID devices corresponding to the one or more sample RFID devices). Thus, the reconfigured plurality of differently configured sample RFID devices are integrated into an electronic article theft prevention system. The electronic article theft prevention system further includes an RFID reader for reading the one or more sample RFID devices, each RFID device including a unique digital indicator based on the performance configuration information of the one or more RFID devices (obtained from the digital database). This enables the electronic article theft prevention system (including the RFID reader of the detection zone) to digitally consider the behavior of all sample RFID devices placed in the inventory zone, thereby enabling the reader of the detection zone (door) to sound an alarm when any product is stolen. At the same time, it ensures that false alarms are not generated due to excessive reading.

[0032] In another embodiment, the reconfiguration of the plurality of differently configured sample RFID devices involves physically modifying one or more of the sample RFID devices. For example, the specific physical modifications performed on each sample RFID device 10, 12 may be different without departing from the scope of the invention. In this example, the antenna configuration of one or both of the RFID devices 10 and 12 may be different. This may include changing (increasing or decreasing) the antenna size (which may include changing the surface area and / or thickness of the antenna), the antenna shape (including the shape of the antenna periphery and the number, size and / or configuration of any gaps defined within the periphery) and / or the material composition of at least a portion of the antenna (for example, using conductive ink instead of aluminum foil or using different materials in different areas of the antenna instead of using the same material in all areas).

[0033] Other possible modifications include, but are not limited to, the nature and configuration of related non-functional components, such as the merchandise associated with the first sample RFID device, and the location at which the first sample RFID device is attached to the associated merchandise. For example, the available mounting space for the first sample RFID device may be made of different materials than adjacent areas, such as metal objects, conductive fabrics, high-density high-dielectric constant materials, etc. The performance of the first sample RFID device depends on its position relative to these other materials in and adjacent to the mounting space, so that the position of the first sample RFID device relative to these areas may be changed to modify the performance of the first sample RFID device, thereby helping the first sample RFID device to converge with the entire set of sample RFID devices used in electronic article theft prevention systems.

[0034] Reconfiguring the sample RFID device may also (or additionally) include changing one or more characteristics of the RFID chip, such as sensitivity, input capacitance, and an identifier of the RFID chip. While physical modifications to the sample RFID device may need to be performed in a production facility, certain modifications to the RFID chip of the sample RFID device can be performed at the test site. For example, in an exemplary embodiment, the sample RFID device is tested by associating it with merchandise and placing it in a stock area of ​​an electronic article theft prevention system that integrates an RFID device (if possible) or in an environment close to such an electronic article theft prevention system. When the store or environment is in a determined state (e.g., no customers), an RFID reader of the electronic article theft prevention system that is only used to detect sample RFID devices in the stock area is activated, and any sample RFID device that can be read in the stock area tag is detected. Then, the electronic article theft prevention system (or the stock area local system) sends a command to the RFID chip of the detected sample RFID device that can change the selected parameters (e.g., chip sensitivity, input capacitance, and identifier) ​​to prevent the sample RFID device from being read by the RFID reader associated with the detection area, thereby improving convergence. In another exemplary embodiment, an RFID reader that detects a detection zone may read a sample RFID device in an inventory zone, but an RFID reader associated with the inventory zone (e.g., an overhead reader system) also reads the same sample RFID device at the same time. The parameters of some or all of the RFID chips in the detected sample RFID devices are then changed to maintain inventory performance and eliminate false positive reads by the RFID reader associated with the electronic article surveillance system detection zone.

[0035] For example, from Figure 2 It can be seen that compared with the first sample RFID device 10 ( Figure 1 ) and the performance of the reconfigured first sample RFID device 10'( Figure 3), the performance of the second sample RFID device 12 is compared with the performance of the reconfigured second sample RFID device 12'( Figure 3 ) are more similar. Therefore, it may be the case that reconfiguring the first sample RFID device 10 requires more (and / or more significant) modifications than reconfiguring the second sample RFID device 12. Depending on the relative performance of the two sample RFID devices over the frequency range, only one sample RFID device may be reconfigured to simulate or approach the performance of the other sample RFID device. However, it is often the case that both sample RFID devices must be reconfigured, at least slightly, due to various restrictions on the configuration of the sample RFID devices. For example, the maximum surface area of ​​the antenna of the sample RFID device may be limited, and if it is desired to increase the surface area of ​​the antenna to exceed the maximum size, some other aspect of the RFID device must be changed. If there is no other aspect that can be changed to compensate for the limitation on the size of the antenna surface area (for example, because the material composition and / or thickness of the antenna is not allowed to be changed), it may be necessary to change some aspect of the other sample RFID device so that the performance of the sample RFID devices converges.

[0036] Without departing from the scope of the present invention, the point at which the performance of two differently configured sample RFID devices is sufficiently similar that the two devices are suitable for use in the same electronic article surveillance system may vary. If a smaller transition zone is required, a higher degree of similarity may be required, while if the transition zone is likely to be larger, a lower degree of similarity may be acceptable. Other factors (e.g., the nature of the RFID readers used in the electronic article surveillance system and the importance of avoiding false alarms) may also be considered in determining the necessary degree of similarity between the performance of two differently configured sample RFID devices over a frequency range. It may be the case that a single redesign of the sample RFID devices may not be sufficient, and it may be necessary to perform multiple repetitive tests of the reconfigured sample RFID devices and then reconfigure one or more of the devices before the performance of the devices can be considered to be converging.

[0037] In some embodiments, the same initial sample RFID template may be used to produce sample RFID devices of different configurations to be integrated into a common electronic article surveillance system. The template may have an initial configuration that is different from at least one (if not all) of the final configurations, for example, a first final configuration of the sample RFID device is integrated into an electronic article surveillance system. Preferably, the template has a configuration that allows for large-scale construction at low cost, and may have a sufficiently simple or basic configuration to be reconfigured not only for different RFID devices used in one electronic article surveillance system, but also for sample RFID devices of different configurations used in multiple different electronic article surveillance systems. Depending on the desired final configuration, the template may be modified by any method, which may include cutting to change the overall shape of the antenna, laser modification of the conductor, or addition of overprinting materials (e.g., as conductors, resistive materials, dielectrics, and magnetic materials) to change performance, thereby establishing a set of sample RFID devices of different configurations for a particular electronic article surveillance system and product combination, and these sample RFID devices have a second final configuration to make the performance consistent over the frequency range. For example, in one embodiment, at least one of the first final configuration and the second final configuration includes an overprinted magnetic material that was not included in the initial configuration of the sample RFID template. In another embodiment, at least one of the first final configuration and the second final configuration includes an overprinted dielectric material that was not included in the initial configuration. In another embodiment, at least one of the first final configuration and the second final configuration includes an overprinted conductive material that was not included in the initial configuration. In another embodiment, at least one of the first final configuration and the second final configuration includes an overprinted magnetic material that was not included in the initial configuration.

[0038] It will be appreciated that the above embodiments illustrate some applications of the principles of the subject matter. Various modifications may be made by those skilled in the art without departing from the spirit or scope of the claimed subject matter, including the combination of features disclosed or claimed herein. For these reasons, the scope of the invention is not limited to the above description, but is set forth in the claims, and it will be appreciated that the claims may be directed to features of the invention, including the combination of features disclosed or claimed herein.

Claims

1. A method for producing a radio frequency identification device for an electronic commodity anti-theft system, the method comprising: providing a plurality of sample radio frequency identification devices having the same initial configuration; reconfiguring one of the plurality of sample RFID devices to have a first final configuration; reconfiguring another one of the plurality of sample RFID devices to have a second final configuration; and A sample RFID device having a first final configuration and a second final configuration is integrated into an electronic article surveillance system, wherein the first final configuration is different from the second final configuration; as well as The performance of the sample RFID device in the first final configuration and the second final configuration employed in the electronic article surveillance system is sufficiently similar over the frequency or frequency range.

2. The method according to claim 1, wherein: The antenna size of at least one of the first final configuration and the second final configuration of the sample RFID device is different from the antenna of the initial configuration.

3. The method according to claim 1, wherein: The antenna shape of at least one of the first final configuration and the second final configuration of the sample RFID device is different from the antenna of the initial configuration.

4. The method according to claim 1, wherein: At least one of the first final configuration and the second final configuration includes an overprinted resistor material that was not included in the initial configuration.

5. The method according to claim 1, wherein: At least one of the first final configuration and the second final configuration includes an overprinted dielectric material that was not included in the initial configuration.

6. The method according to claim 1, wherein: At least one of the first final configuration and the second final configuration includes an overprinted conductive material that was not included in the initial configuration.

7. The method according to claim 1, wherein: At least one of the first final configuration and the second final configuration includes an overprinted magnetic material that was not included in the initial configuration.

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