Antenna system, direction discrimination system, and direction discrimination method

Abstract

The embodiment of the application provides an antenna system, a direction distinguishing system and a direction distinguishing method, the antenna system comprises a first antenna body and a second antenna body; the second antenna body is a directional antenna which is composed of an included angle reflector, an antenna and a composite dielectric block, wherein the antenna is located in the interior of the composite dielectric block, and the central direction of the included angle reflector of each second antenna body is different. The embodiment of the application improves the radio frequency tag identification accuracy.

Description

Technical Field

[0001] This application relates to the field of radio frequency identification technology, and in particular to an antenna system, a direction determination system, and a direction determination method. Background Technology

[0002] Radio Frequency Identification (RFID) technology is a communication technology that can identify specific targets and read / write related data via radio signals without requiring mechanical or optical contact between the identification system and the target. RFID tags, as a crucial component of an RFID system, significantly impact the overall performance of the RFID system.

[0003] In some RFID application scenarios, RFID systems need to accurately identify target RFID tags that meet certain conditions, such as target RFID tags whose movement direction matches a preset movement direction. However, RFID systems often experience cross-reading, which can easily lead to misreading of other non-target RFID tags in the environment, resulting in low RFID tag identification accuracy.

[0004] For example, in supply chain management, RFID technology is commonly used to manage logistics vehicles. RFID-based gate systems, by installing RFID tags on logistics vehicles and RFID data collection devices at key points such as gates, provide a more convenient and faster way to obtain logistics vehicle information compared to barcode reading systems. In supply chain management, accurate information about the entry and exit of logistics vehicles is often required, such as whether a vehicle is leaving or entering a warehouse. However, conventional RFID gate systems frequently experience cross-reading, such as misreading non-target RFID tags on other logistics vehicles in the environment, or RFID tags on vehicles moving within the warehouse, leading to low accuracy in RFID tag identification. Summary of the Invention

[0005] This application provides an antenna system, a direction determination system, and a direction determination method to solve the problem of low accuracy in RFID tag reading.

[0006] To address the aforementioned problems, this application discloses an antenna system comprising: First antenna body and second antenna body; the first antenna body and the second antenna body are separately disposed; The second antenna body is a directional antenna composed of an angle reflector, an antenna, and a composite dielectric block, wherein the antenna is located inside the composite dielectric block, and the center direction of the angle reflector of each second antenna body is different.

[0007] Optionally, the included-angle reflector is composed of two reflectors arranged at a certain angle; the antenna system further includes a reading and writing device mounting area based on the reflectors, the reading and writing device mounting area being located between the second antenna bodies, and the first antenna body being mounted on the reflector outside the reading and writing device mounting area.

[0008] Optionally, the antenna system further includes a housing for encapsulating the first antenna body and the second antenna body; the antenna system also includes a parasitic unit, which is fixed to the side of the housing and disposed on the opposite side of the included angle reflector relative to the antenna of the second antenna body.

[0009] Optionally, the composite dielectric block is polyhedral in shape and is composed of foamed material and ceramic plate, wherein the ceramic plate is embedded inside the foamed material; the parasitic unit is formed by winding a spiral on a cylindrical plastic substrate; the first antenna body is a microstrip antenna, and the antenna in the second antenna body is a dipole antenna; the reflector is a metal plate.

[0010] This application embodiment also provides a direction determination system, which includes the antenna system and radio frequency read / write device as described above: The radio frequency (RF) reader / writer is installed between the first antenna body and the second antenna body of the antenna system. It acquires the RF tag information transmitted by the RF tag through the first antenna body and the second antenna body, and determines the movement direction of the RF tag based on the RF tag information.

[0011] Optionally, the radio frequency (RF) reader / writer is installed in the reader / writer installation area; wherein, the antenna of each of the second antenna bodies is connected to the antenna interface of the RF reader / writer via an RF coaxial line passing through the composite dielectric block and the reflector of the reader / writer installation area; the first antenna body is connected to the antenna interface of the RF reader / writer via an RF coaxial line passing through the reflector of the reader / writer installation area.

[0012] This application embodiment also provides a direction determination method, applied to the direction determination system as described above, the method comprising: When the RFID tag moves, RFID tag information is collected at different positions; The direction of movement of the RFID tag is determined based on the RFID tag information corresponding to each of the aforementioned locations.

[0013] Optionally, the RFID tag information includes antenna ports and signal strength indication values ​​sorted by acquisition time; the antenna ports include ports connected to the first antenna body and ports connected to the antennas of each of the second antenna bodies; the signal strength indication value acquired when the RFID tag is in the center direction of the included angle reflector of the second antenna body is higher than the signal strength indication value acquired when the RFID tag is deviated from the center direction of the included angle reflector of the second antenna body.

[0014] Optionally, determining the movement direction of the RFID tag based on the RFID tag information corresponding to each location includes: Based on the signal strength indication value corresponding to each location, the target signal strength indication value collected when the center direction of the included angle reflector of the second antenna body is selected. The direction of movement of the RFID tag is determined based on the acquisition time corresponding to the target signal strength indication value.

[0015] Optionally, determining the movement direction of the RFID tag based on the RFID tag information corresponding to each location further includes: The radio frequency tag whose movement direction satisfies the preset movement direction is identified as the target radio frequency tag, and the radio frequency tag whose movement direction does not satisfy the preset movement direction is identified as the interference radio frequency tag; Based on the RFID tag information corresponding to the first antenna body, the RFID tags whose movement direction does not meet the preset movement direction are checked to determine whether they are interfering RFID tags. Compared with the prior art, the embodiments of this application have the following advantages: In this embodiment of the application, the antenna system may include a first antenna body and a second antenna body, which are separately arranged in the antenna system. The second antenna body is a directional antenna composed of an angle reflector, an antenna and a composite dielectric block. The antenna is located inside the composite dielectric block, and the center direction of the angle reflector of each second antenna body is different. In this embodiment, the second antenna body is a directional antenna. Therefore, the signal strength of electromagnetic waves (e.g., RFID information transmitted by an RFID tag) received at the center direction of the included-angle reflector of the second antenna body is generally stronger than that received at the center direction of the non-included-angle reflector of the second antenna body. Moreover, there are multiple second antenna bodies in this embodiment, and the center directions of the included-angle reflectors of the second antenna bodies are different. Therefore, when the antenna system of this embodiment is applied to an RFID system, based on the multiple antennas in the antenna system, i.e., the second antenna bodies, the RFID tag information corresponding to the RFID tag at different positions can be collected. Since the second antenna body is a directional antenna, and the center directions of the included-angle reflectors of each second antenna body are different, the signal strength of the RFID tag information collected by the second antenna body at different positions is different. It is possible to determine whether the RFID tag has passed through at least two target positions based on the signal strength, and then determine the movement direction of the RFID tag based on the two target positions, and determine whether the RFID tag is the target RFID tag based on the movement direction, thereby improving the accuracy of RFID tag identification. Furthermore, in this embodiment of the application, radio frequency tags (RFTs) whose movement direction meets the preset movement direction can be identified as target RFTs, and RFTs whose movement direction does not meet the preset movement direction can be identified as interfering RFTs. The RFT information of the RFTs collected by the first antenna body is used to verify whether the RFTs whose movement direction does not meet the preset movement direction are interfering RFTs, thereby further improving the accuracy of RFT identification. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the structure of an antenna system according to an embodiment of this application; Figure 2 This is a schematic diagram of the installation structure of a direction determination system according to an embodiment of this application; Figure 3 This is a flowchart illustrating the steps of an embodiment of the direction determination method of this application; Figure 4 This is a schematic diagram of the application structure of a direction discrimination system according to an embodiment of this application.

[0017] Figure label: 1. First antenna body; 2. Second antenna body; 21. Antenna; 22. Antenna; 23. Antenna; 4. Composite dielectric block; 5. Reflector; 6. Reader / writer installation area; 7. Housing; 8. Bracket. Detailed Implementation

[0018] To make the above-mentioned objectives, features and advantages of this application more apparent and understandable, the application will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0019] First, some key terms involved in the embodiments of this application will be introduced: Multipath effect: This refers to the phenomenon where electromagnetic wave signals propagate through different paths, and the different component fields arrive at the receiving end at different times. They then superimpose with each other according to their respective phases, causing interference and resulting in distortion or errors in the original signal.

[0020] In practice, radio frequency identification (RFID) technology has a wide range of applications. For example, RFID technology can be applied to supply chain management. Specifically, in supply chain management, it is usually necessary to obtain accurate information on the entry and exit of logistics vehicles, such as whether the logistics vehicle is leaving or entering the logistics warehouse.

[0021] Currently, there are two common RFID system solutions for managing the entry and exit of logistics vehicles. One solution involves setting up an RFID gate system, allowing the automatic identification of RFID tags on logistics vehicles as they pass through the gate, eliminating the need for manual tag collection. However, a drawback is that environmental interference and multipath effects can lead to misreading of RFID tags from nearby vehicles (e.g., those not entering or leaving the warehouse). Furthermore, the limited data dimension makes it difficult to eliminate interfering tags using algorithms. The other solution involves manual collection of RFID tag information from logistics vehicles using low-power handheld readers at close range. While manual reading offers higher accuracy and typically avoids cross-reading, it is less efficient and incurs additional labor costs.

[0022] In view of this, embodiments of this application propose a multi-antenna system, a direction determination system, and a direction determination method based on an angle reflector to avoid the above-mentioned drawbacks.

[0023] Reference Figure 1 This is a schematic diagram of an antenna system according to an embodiment of this application. The antenna system may specifically include: a first antenna body 1 and a second antenna body 2, which are separately arranged in the antenna system; the second antenna body 2 is a directional antenna composed of an angle reflector, an antenna and a composite dielectric block, wherein the antenna is located inside the composite dielectric block, and the center direction of the angle reflector of each second antenna body is different.

[0024] A directional antenna is an antenna that emits and receives electromagnetic waves very strongly in one or several specific directions, while emitting and receiving electromagnetic waves in other directions is zero or very weak.

[0025] In this embodiment, the second antenna body 2 is a directional antenna. Therefore, the signal strength of electromagnetic waves (e.g., RFID information transmitted by an RFID tag) received at the center direction of the included-angle reflector of the second antenna body 2 is generally stronger than that received at the center direction of the non-included-angle reflector of the second antenna body 2. Moreover, there are multiple second antenna bodies 2 in this embodiment, and the center directions of the included-angle reflectors of the second antenna bodies 2 are different. Therefore, when the antenna system of this embodiment is applied to an RFID system, based on the multiple antennas in the antenna system, i.e., the second antenna body 2, it can collect RFID information corresponding to the RFID tag at different positions. Since the second antenna body 2 is a directional antenna, and the center directions of the included-angle reflectors of each second antenna body 2 are different, the signal strength of the RFID tag information collected by the second antenna body at different positions is different. It is possible to determine whether the RFID tag has passed through at least two target positions based on the signal strength, and then determine the movement direction of the RFID tag based on the two target positions, and determine whether the RFID tag is the target RFID tag based on the movement direction, thereby improving the accuracy of RFID tag identification. Furthermore, in this embodiment of the application, radio frequency tags (RFTs) whose movement direction meets the preset movement direction can be identified as target RFTs, and RFTs whose movement direction does not meet the preset movement direction can be identified as interfering RFTs. The RFT information of the RFTs collected by the first antenna body 1 is used to verify whether the RFTs whose movement direction does not meet the preset movement direction are interfering RFTs, thereby further improving the accuracy of RFT identification.

[0026] As a specific example, there can be one first antenna body 1 and multiple second antenna bodies 2. For instance, the antenna system can include three second antenna bodies 2, with the antennas in these three second antenna bodies 2 being antennas 21, 22, and 23 as shown in the figure. Each second antenna body 2 also includes a composite dielectric block 4. The first antenna body 1 can be a microstrip antenna, and the antennas in the second antenna bodies 2 can be dipole antennas of stimulated antennas. An angle reflector is formed by assembling two reflector plates 5 at a certain angle; for example, the two reflector plates can be arranged at 90° or other angles. The reflector plates 5 can be metal plates.

[0027] The dielectric constant is a key parameter reflecting the dielectric or polarization properties under the influence of an electrostatic field. In this embodiment, the polyhedral composite dielectric block 4 can be composed of foamed material and a ceramic plate, with the ceramic plate embedded within the foamed material. The combination of the extremely lightweight foamed material and the ceramic plate with its extremely high dielectric constant allows the composite dielectric block to achieve a high dielectric constant at a low cost and weight. This enables higher gain and lower-order radiation mode lobe patterns when the distance between the antenna of the second antenna body and the center of the angle reflector is relatively small. In one example of this application, the dielectric constant of the composite dielectric block 4 can be equivalent to 3. The distance between the dipole antenna (acting as a stimulated antenna) and the center of the angle reflector is 50 mm, slightly higher than 1 / 4 wavelength, exhibiting good directional performance.

[0028] The antenna system also includes a reading and writing device installation area based on reflectors 5. The reading and writing device installation area 6 is located between multiple second antenna bodies 2. The first antenna body 1 can be installed on the reflectors 5 outside the reading and writing device installation area, so that the first antenna body 1 and the second antenna body 2 surround the reading and writing device installation area 6.

[0029] As a concrete example, refer to Figure 1 The antenna system of this application embodiment may include a first antenna body 1 and three second antenna bodies 2 based on angle reflectors. The second antenna body 2 includes three 90° angle reflectors composed of reflectors 5, three dipole antennas (i.e., antenna 21, antenna 22, and antenna 23) as stimulated antennas, and three polyhedral composite dielectric blocks 4. Among them, antennas 21, antenna 22, and antenna 23, which are stimulated antennas, are located inside the composite dielectric blocks. In this application embodiment, the five reflectors 5 form a reading / writing device mounting area 6 with a hollow cuboid cross-section and three 90° angle reflectors.

[0030] The antenna system also includes a housing 7, which encapsulates the first antenna body 1 and the second antenna body 2. The housing 7 may be composed of an engineering plastic sheet, as shown in the reference. Figure 1 The outer casing 7 may include four engineering plastic panels on the sides, and one engineering plastic panel on the top and one on the bottom. Figure 1 (Not shown in the text) consists of...

[0031] The antenna system also includes a parasitic element 3, which is fixed to the side of the housing and positioned on the opposite side of the included-angle reflector, with the antenna of each second antenna body as a reference. The parasitic element 3 is formed by winding a spiral wire around a cylindrical plastic substrate; therefore, it can also be called a spiral parasitic element. Specifically, the function of the parasitic element 3 is to change the polarization of the antenna of each second antenna body 2 from linear polarization to circular polarization, thus preventing significant polarization loss between the antenna system and the RFID tag antenna when applied to an RFID system.

[0032] Based on the antenna system embodiments described above, this application also provides a direction discrimination system. The direction discrimination system may include an antenna system and a radio frequency reading and writing device. That is, a direction discrimination system capable of discriminating the movement direction of radio frequency tags can be realized by installing the radio frequency reading and writing device on the antenna system.

[0033] The radio frequency (RF) reader / writer can be installed between the first antenna body 1 and the second antenna body 2 of the antenna system, thereby obtaining the RF tag information transmitted by the RF tag through the first antenna body 1 and the second antenna body 2, and then determining the movement direction of the RF tag based on the RF tag information.

[0034] Specifically, refer to Figure 1 The radio frequency (RF) reader / writer can be installed in the reader / writer installation area 6. The antenna of each second antenna body 2 can be connected to the antenna interface of the RF reader / writer via an RF coaxial cable passing through the composite dielectric block and the reflector of the reader / writer installation area. The first antenna body 1 can also be connected to the antenna interface of the RF reader / writer via an RF coaxial cable passing through the reflector of the reader / writer installation area.

[0035] As an optional example, see Figure 2 This is a schematic diagram of the installation structure of a direction determination system according to an embodiment of this application. The direction determination system can be placed at any location where RFID tag information needs to be collected, via a bracket 8 composed of a support column and a base. In practical applications, even if the RFID tags to be collected need to be adjusted, only the position of the direction determination system needs to be simply moved.

[0036] Based on the above-described direction determination system embodiments, this application also provides a direction determination method, referring to... Figure 3 This is a flowchart illustrating the steps of an embodiment of a direction determination method according to this application, including the following steps: Step 301: When the RFID tag moves, collect the RFID tag information at different positions; In a specific implementation, an RFID system can be formed based on the aforementioned direction discrimination system and radio frequency device. Based on the direction discrimination system in this RFID system, when the RFID tag moves, the RFID tag information at different positions is collected. Then, the direction of movement of the RFID tag can be determined according to the RFID tag information corresponding to each position.

[0037] The RFID tag information may include at least the antenna port and signal strength indication values ​​sorted by acquisition time. Specifically, the antenna port may include at least the port connected to the first antenna body 1 and the port connected to the antennas of each second antenna body 2. The signal strength indication value refers to the RSSI (Received Signal Strength Indication) value, and when the RSSI value is acquired, the acquisition time corresponding to the RSSI value can also be saved.

[0038] Step 302: Determine the movement direction of the RFID tag based on the RFID tag information corresponding to each of the aforementioned locations.

[0039] In this embodiment of the application, when collecting RFID tag information at different locations, the movement direction of the RFID tag can be determined based on the RFID tag information corresponding to each location.

[0040] In an exemplary embodiment of this application, step 302, determining the movement direction of the RFID tag based on the RFID tag information corresponding to each location, may include the following steps: Based on the signal strength indication value corresponding to each location, the target signal strength indication value collected when the center direction of the included angle reflector of the second antenna body is selected. The direction of movement of the RFID tag is determined based on the acquisition time corresponding to the target signal strength indication value.

[0041] As described above, in the direction determination system of this application embodiment, the RSSI value of the radio frequency signal received in the center direction of the included-angle reflector of the second antenna body 2 is generally stronger than the RSSI value of the radio frequency signal received in the center direction of the non-included-angle reflector of the second antenna body 2. Furthermore, the center directions of the included-angle reflectors of the second antenna body 2 are different. That is, when the RFID tag is in the center direction of a certain included-angle reflector of the second antenna body 2, the RSSI value of the RFID tag collected is generally stronger than the RSSI value of the RFID tag collected in the non-included-angle reflector direction of the second antenna body 2. Therefore, it can be determined that the RFID tag is currently... The position is in the center direction of the included angle reflector of the second antenna body 2. Since there are multiple second antenna bodies 2 in this embodiment, for example, there can be three second antenna bodies 2 in a direction discrimination system, if it is determined that when the radio frequency tag is moving, the RSSI value of the radio frequency tag collected by two second antenna bodies 2 is stronger than the RSSI value of the radio frequency tag collected by other radio frequency tags, it can be determined that the radio frequency tag has passed through these two second antenna bodies 2 when it moves. Then, the center direction of the included angle reflector corresponding to these two second antenna bodies 2 can be further combined with the collection time in the radio frequency tag information to determine the moving direction of the radio frequency tag.

[0042] In an exemplary embodiment of this application, step 302, determining the movement direction of the RFID tag based on the RFID tag information corresponding to each location, may further include the following steps: The radio frequency tag whose movement direction satisfies the preset movement direction is identified as the target radio frequency tag, and the radio frequency tag whose movement direction does not satisfy the preset movement direction is identified as the interference radio frequency tag; Based on the RFID tag information corresponding to the first antenna body, the RFID tags whose movement direction does not meet the preset movement direction are checked to determine whether they are interference RFID tags.

[0043] Furthermore, in this embodiment of the application, after determining the moving direction of the RFID tag, it is possible to determine whether the RFID tag is the target RFID tag based on whether the moving direction is a preset moving direction.

[0044] In specific implementation, when the RFID tag is located at the center of the angle reflector of the second antenna body 2 in the direction discrimination system, and the corresponding excited dipole antenna is in working state, the RSSI value obtained by the RFID reader / writer is high. When the RFID tag deviates from the center of the angle reflector, the RSSI value decays rapidly because the second antenna body 2, as a directional antenna, is in a low-order radiation mode and has a narrow beamwidth, resulting in a low RSSI value obtained by the RFID reader / writer. Compared with conventional RFID readers / writers, the direction discrimination system of this embodiment is less affected by multipath effects, and the movement direction of the RFID tag can be easily identified based on the magnitude of the RSSI value. When the RFID tag in this embodiment moves, if the RFID reader / writer obtains a high RSSI value for the RFID tag through at least two second antenna bodies 2, it can be determined that the RFID tag is located at the center of the angle reflector of these two second antenna bodies 2. Based on these two positions, the movement direction of the RFID tag can be determined, and based on whether the movement direction is a preset movement direction, it can be determined whether it is a target RFID tag or an interfering RFID tag. Furthermore, the RFID tag can be verified by checking the first antenna body 1 to confirm that it is indeed an interfering RFID tag.

[0045] An embodiment of this application provides a direction discrimination system that can accurately locate the movement direction of a target RFID tag during its movement by using three second antenna bodies 2 composed of angle reflectors. The first antenna body 1, which has a relatively wide beamwidth and is a microstrip antenna, plays an auxiliary role in the judgment. The direction discrimination system formed by the combination of the first antenna body 1 and the second antenna body 2 improves the accuracy of RFID tag identification.

[0046] As a specific example, in the context of a logistics supply chain, it is often necessary to obtain accurate information on the entry and exit of logistics vehicles, such as whether the logistics vehicle is leaving or entering the logistics warehouse. This embodiment of the application can achieve this by installing RFID tags on the logistics vehicles and installing a direction determination system on one side of the warehouse access door, setting the preset movement direction as leaving or entering the logistics warehouse. Then, the direction determination system can collect the RFID tag information from the RFID tags in the logistics vehicles, and determine whether the movement direction of the RFID tag is the preset movement direction based on the RFID tag information. If the movement direction of the RFID tag is the preset movement direction, it means that the logistics vehicle corresponding to the RFID tag is leaving or entering the logistics warehouse, and the RFID tag is determined to be a target RFID tag. If the movement direction of the RFID tag is not the preset movement direction, it means that the logistics vehicle corresponding to the RFID tag may be moving within the logistics warehouse, and the RFID tag is determined to be a non-target RFID tag, i.e., an interfering RFID tag. By identifying target and interfering RFID tags, automatic inventory management and entry / exit management can be performed in the logistics supply chain, achieving overall control of the logistics warehouse.

[0047] To enable those skilled in the art to better understand the embodiments of this application, a specific example is used below to illustrate the direction determination process of the embodiments of this application. (Refer to...) Figure 4 This is a schematic diagram of the application structure of a direction discrimination system according to an embodiment of this application. Specifically, the direction discrimination system and the logistics vehicle equipped with RFID tags form an RFID inbound / outbound channel door system. The direction discrimination system may include a first antenna body 1 and three second antenna bodies 2. The antennas corresponding to the three second antenna bodies 2 are antenna 21, antenna 22 and antenna 23, respectively. The direction discrimination system is located on the side of the channel door of the logistics warehouse. When the logistics vehicle equipped with RFID tags moves from inside the logistics warehouse to outside the channel door (exiting the logistics warehouse), it needs to first pass through position C to move to position B, and then move to position A. In this process, firstly, the RFID reader / writer in the direction determination system acquires a set of multiple RSSI values ​​C22 during the time period TC, obtained via antenna 22. C22 includes higher RSSI values ​​returned when the RFID tag is located in the center direction of the included-angle reflector corresponding to antenna 21. Then, the RFID reader / writer acquires a set of multiple RSSI values ​​B1 during the time period TB, obtained via the first antenna body 1. B1 includes multiple RSSI values ​​of varying values ​​from highest to lowest, ordered by time from the RFID tag. Finally, the RFID reader / writer acquires a set of multiple RSSI values ​​A21 during the time period TA, obtained via antenna 21. A21 includes higher RSSI values ​​returned when the RFID tag is located in the center direction of its corresponding included-angle reflector. It can be understood that if antennas 22 and 21 in the direction determination system acquire higher RSSI values ​​corresponding to the RFID tag, the movement direction of the RFID tag—whether it is moving out of or into the logistics warehouse—can be determined by combining the acquisition time, and the RFID tag belonging to the out-of-warehouse category can be identified as the target RFID tag.

[0048] It should be noted that although the direction determination system can collect the RSSI value of the target RFID tag as well as the RSSI values ​​of surrounding non-target RFID tags during the entire process, in order to reduce interference, this embodiment of the application can also analyze the RFID tag information of all the collected RFID tags through an algorithm, thereby accurately filtering out the target RFID tags that contain features such as acquisition time, antenna port, and RSSI value that approximate the aforementioned feature description, i.e., those that meet the characteristics of leaving the logistics warehouse. Similarly, when a logistics vehicle with an RFID tag moves from outside the passageway to inside the logistics warehouse, from position A to B and then to C, its feature descriptions such as acquisition time, antenna port, and RSSI value should be the opposite of the feature description of leaving the logistics warehouse, which will not be elaborated here.

[0049] In conventional RFID inbound / outbound gate systems, it is often difficult to distinguish other non-target RFID tags moving within the logistics warehouse from the target RFID tag that is currently performing inbound / outbound operations. Figure 4 In the logistics vehicle entry and exit scenario shown, when a non-target RFID tag only matches the feature descriptions of position C and position D, it can be marked as a moving interference RFID tag in the logistics warehouse. Even if the first antenna body 1, which is susceptible to multipath effects, reads the interference RFID tag at the same time, it can be further determined whether it is an interference RFID tag by whether it matches the RFID tag information such as the time of entry and exit, antenna port, and RSSI value, which further improves the accuracy of RFID tag identification.

[0050] The direction discrimination system of this application embodiment for the direction discrimination method includes a first antenna body 1 and a second antenna body 2. As an optional example, the antenna system in the direction discrimination system can be a four-antenna system. Specifically, the first antenna body can be a microstrip antenna, and the second antenna body 2 can be three directional antennas composed of angle reflectors, antennas and composite dielectric blocks. Through the direction discrimination system of the four-antenna system, the electromagnetic field coverage area can be planned reasonably according to the needs of the logistics vehicle entry and exit scenarios in the logistics warehouse, such as whether it is leaving or entering the logistics warehouse, to reduce the impact of multipath effects and improve the accuracy of RFID tag reading.

[0051] It should be noted that the antenna system, direction determination system and direction determination method of this application embodiment can be applied not only to logistics supply chain scenarios, but also to vehicle automatic identification, production automation and process control, smart healthcare, personnel management, logistics distribution, etc. This application embodiment does not impose any limitations on these applications.

[0052] Other embodiments of this specification will readily occur to those skilled in the art upon consideration of the specification and practice of the invention disclosed herein. This specification is intended to cover any variations, uses, or adaptations that follow the general principles of this specification and include common knowledge or customary techniques in the art not disclosed herein. The specification and examples are to be considered exemplary only, and the true scope and spirit of this specification are indicated by the following claims.

[0053] It should also be noted that the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0054] The above description is merely a preferred embodiment of this specification and is not intended to limit this specification. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this specification should be included within the scope of protection of this specification.

[0055] The antenna system, direction discrimination system, and direction discrimination method provided in this application have been described in detail above. Specific examples have been used to illustrate the principles and implementation methods of this application. The description of the above embodiments is only for the purpose of helping to understand the method and core ideas of this application. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of this application. Therefore, the content of this specification should not be construed as a limitation of this application.

Claims

1. An antenna system, characterized in that, The antenna system includes: First antenna body and second antenna body; the first antenna body and the second antenna body are separately disposed; The second antenna body is a directional antenna composed of an angle reflector, an antenna, and a composite dielectric block, wherein the antenna is located inside the composite dielectric block; the first antenna body is used to verify whether a radio frequency tag whose movement direction does not meet the preset movement direction is an interfering radio frequency tag; the movement direction is determined according to the target signal strength indication value collected by the second antenna body in the center direction of the angle reflector.

2. The antenna system according to claim 1, characterized in that, The included angle reflector is composed of two reflective plates arranged at a certain angle; The antenna system further includes a read / write device mounting area based on the reflector, the read / write device mounting area being located between the second antenna bodies, and the first antenna body being mounted on the reflector outside the read / write device mounting area.

3. The antenna system according to claim 2, characterized in that, The antenna system further includes a housing for encapsulating the first antenna body and the second antenna body; the antenna system also includes a parasitic unit, which is fixed to the side of the housing and disposed on the opposite side of the included angle reflector with reference to the antenna of the second antenna body.

4. The antenna system according to claim 3, characterized in that, The center directions of the included angle reflectors of each of the second antenna bodies are different; the composite dielectric block is polyhedral in shape, and the composite dielectric block is composed of foamed material and ceramic plate, wherein the ceramic plate is embedded inside the foamed material; the parasitic unit is formed by winding a spiral on a cylindrical plastic substrate; the first antenna body is a microstrip antenna, and the antenna in the second antenna body is a dipole antenna; the reflector is a metal plate.

5. A direction determination system, characterized in that, The direction determination system includes the antenna system and radio frequency reading / writing device as described in any one of claims 1 to 4: The radio frequency (RF) reader / writer is installed between the first antenna body and the second antenna body of the antenna system. It acquires the RF tag information transmitted by the RF tag through the first antenna body and the second antenna body, and determines the movement direction of the RF tag based on the RF tag information.

6. The direction determination system according to claim 5, characterized in that, The radio frequency (RF) read / write device is installed in the read / write device installation area; wherein, the antenna of each of the second antenna bodies is connected to the antenna interface of the RF read / write device via an RF coaxial line passing through the composite dielectric block and the reflector of the read / write device installation area; the first antenna body is connected to the antenna interface of the RF read / write device via an RF coaxial line passing through the reflector of the read / write device installation area.

7. A direction determination method, characterized in that, The method, applied to the direction determination system as described in any one of claims 5 to 6, comprises: When the RFID tag moves, RFID tag information is collected at different positions; The direction of movement of the RFID tag is determined based on the RFID tag information corresponding to each of the aforementioned locations.

8. The direction determination method according to claim 7, characterized in that, The RFID tag information includes antenna ports and signal strength indication values ​​sorted by acquisition time; the antenna ports include ports connected to the first antenna body and ports connected to the antennas of each of the second antenna bodies; the signal strength indication value acquired when the RFID tag is in the center direction of the included angle reflector of the second antenna body is higher than the signal strength indication value acquired when the RFID tag is deviated from the center direction of the included angle reflector of the second antenna body.

9. The direction determination method according to claim 8, characterized in that, The step of determining the movement direction of the RFID tag based on the RFID tag information corresponding to each location includes: Based on the signal strength indication value corresponding to each location, the target signal strength indication value collected when the center direction of the included angle reflector of the second antenna body is selected. The direction of movement of the RFID tag is determined based on the acquisition time corresponding to the target signal strength indication value.

10. The direction determination method according to claim 9, characterized in that, The step of determining the movement direction of the RFID tag based on the RFID tag information corresponding to each location further includes: The radio frequency tag whose movement direction satisfies the preset movement direction is identified as the target radio frequency tag, and the radio frequency tag whose movement direction does not satisfy the preset movement direction is identified as the interference radio frequency tag; Based on the RFID tag information corresponding to the first antenna body, the RFID tags whose movement direction does not meet the preset movement direction are checked to determine whether they are interference RFID tags.

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