Neighbor ranging and positioning method based on phase and server

Abstract

The invention discloses a neighbor ranging and positioning method based on phase and a server, and the method comprises the steps: transmitting a neighbor phase measurement instruction, so as to schedule an electronic tag transmitting pair which is preset as a transmitting end in a scene to be positioned to sequentially transmit broadcast signals according to a pre-distributed time sequence; after all the electronic tag emission pairs in the scene to be positioned complete broadcast signal emission, receiving neighbor phase measurement results sent by the electronic tags in the scene to be positioned; labels in the scene to be positioned are divided into a plurality of phase difference operation groups according to the result, the distance difference between the labels in each group is calculated in a phase difference operation mode, and each phase difference operation group at least comprises a label emission pair; and determining the position of the to-be-positioned electronic tag in the to-be-positioned scene based on the known position of the anchor tag in the to-be-positioned scene and the distance difference between the electronic tags. According to the invention, the position of the electronic tag can be efficiently and accurately determined.

Description

Technical Field

[0001] This invention relates to the field of positioning technology, and in particular to a phase-based neighbor ranging positioning method and server. Background Technology

[0002] This section is intended to provide background or context for the embodiments of the invention set forth in the claims. The description herein is not an admission that it is prior art simply because it is included in this section.

[0003] The location information of electronic tags in smart warehousing is extremely important, as it can greatly improve the efficiency of warehouse operations. Taking the smart retail industry as an example, the management of in-store merchandise display is a crucial part of its intelligence and digitalization, and accurate location information of goods and shelves is a necessary condition for its realization. Since electronic tags are bound to each product, the location information of the goods and shelves is reflected in the location information of the electronic tags; therefore, obtaining accurate location information of electronic tags is of paramount importance.

[0004] In existing technologies, distance-based electronic tag positioning methods only measure the distance between each pair of electronic tags in each positioning operation, resulting in low efficiency. Furthermore, traditional electronic tag signal ranging schemes rely on bidirectional signal transmission and reception, leading to cumbersome and time-consuming measurement processes. Distance measurement requires tags to possess specialized hardware and corresponding protocols, resulting in relatively weak adaptability and difficulty in meeting the needs of rapid tag network deployment and batch testing scenarios. Additionally, the bidirectional transmission and reception mode is susceptible to channel interference and differences in tag device response, leading to insufficient robustness of phase measurement results; it also exhibits poor compatibility with different protocols and tag device models. Summary of the Invention

[0005] This invention provides a phase-based neighbor ranging and positioning method for efficiently and accurately determining the location of electronic tags. The method includes: Send a neighbor phase measurement command to schedule the electronic tag transmitting pairs in the scene to be located to transmit broadcast signals in a pre-set time sequence according to a pre-allocated time sequence, wherein each shelf aisle in the scene to be located includes at least one pair of electronic tag transmitting pairs; After all electronic tag transmitting pairs in the scene to be located have completed the broadcast signal transmission, the neighbor phase measurement results sent by the electronic tags in the scene to be located are received. Based on the received neighbor phase measurement results, the electronic tags in the scene to be located are divided into multiple phase difference operation groups, and the distance difference between each electronic tag in each phase difference operation group is calculated by phase difference operation. Each phase difference operation group includes at least one pair of electronic tag transmission pairs, and the other electronic tags in the group are electronic tags that receive the broadcast signal of the electronic tag transmission pair. Based on the known location of the anchor point electronic tag in the scene to be located, and the calculated distance difference between each electronic tag in each phase difference operation group, the location of the electronic tag to be located in the scene to be located is determined.

[0006] This invention also provides a phase-based neighbor ranging and positioning server for efficiently and accurately determining the location of electronic tags. The server includes: The transmitting unit is used to send neighbor phase measurement instructions to schedule the electronic tag transmitting pairs in the scene to be located to transmit broadcast signals in a pre-set transmitting end according to a pre-allocated time sequence, wherein each shelf aisle in the scene to be located includes at least one pair of electronic tag transmitting pairs; The receiving unit is used to receive the neighbor phase measurement results sent by the electronic tags in the scene to be located after all electronic tag transmitting pairs in the scene to be located have completed the broadcast signal transmission; The phase difference operation unit is used to divide the electronic tags in the scene to be located into multiple phase difference operation groups according to the received neighbor phase measurement results, and calculate the distance difference between each electronic tag in each phase difference operation group by means of phase difference operation. Each phase difference operation group includes at least one pair of electronic tag transmission pairs, and the other electronic tags in the group are electronic tags that receive the broadcast signal of the electronic tag transmission pair. The positioning unit is used to determine the position of the electronic tag to be positioned in the scene based on the known position of the anchor point electronic tag in the scene to be positioned and the calculated distance difference between each electronic tag in each phase difference operation group.

[0007] This invention also provides a computer device, including a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, it implements the above-described phase-based neighbor ranging and positioning method.

[0008] This invention also provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements the aforementioned phase-based neighbor ranging and positioning method.

[0009] This invention also provides a computer program product, which includes a computer program that, when executed by a processor, implements the above-described phase-based neighbor ranging and positioning method.

[0010] The beneficial technical effects of the phase-based neighbor ranging and localization scheme provided in this embodiment of the invention are: Firstly, in existing technologies, each positioning operation only measures the distance between pairs of electronic tags, resulting in low efficiency. Furthermore, traditional electronic tag signal ranging schemes rely on bidirectional signal transmission and reception, leading to cumbersome and time-consuming measurement processes. To address this issue, the phase-based neighbor ranging positioning scheme provided in this invention sends a neighbor phase measurement command to schedule pre-defined electronic tag transmitting pairs in the positioning scenario to sequentially transmit broadcast signals according to a pre-allocated time sequence. Each shelf aisle in the positioning scenario includes at least one electronic tag transmitting pair. After all electronic tag transmitting pairs in the positioning scenario have completed their broadcast signal transmission, the neighbor phase measurement results sent by the electronic tags in the positioning scenario are received. This allows for rapid collection of phase measurement results from the electronic tags in the positioning scenario, and the electronic tags in the positioning scenario do not need to all undertake the role of broadcast signal transmission, improving measurement efficiency. This invention eliminates the need for bidirectional signal transmission and reception, making it faster, more robust, and more compatible.

[0011] Secondly, in existing technologies, the bidirectional transceiver mode is susceptible to channel interference and differences in tag device response, resulting in insufficient robustness of phase measurement results. Furthermore, it suffers from poor compatibility with different protocols and tag device models, leading to high adaptation costs. To address this issue, the phase-based neighbor ranging and positioning scheme provided in this invention divides the electronic tags in the target location scenario into multiple phase differential operation groups based on the received neighbor phase measurement results. The distance difference between each electronic tag in each phase differential operation group is calculated using phase differential operations. Each phase differential operation group includes at least one pair of electronic tag transmitters, and the other electronic tags in the group are those that have received the broadcast signal from that pair. Based on the known location of the anchor electronic tag in the target location scenario and the calculated distance difference between each electronic tag in each phase differential operation group, the location of the electronic tag to be located in the target location scenario is determined. Determining the electronic tag's location through the distance difference between each electronic tag can offset common errors, such as common channel delays and inherent device biases, thereby improving the positioning accuracy of the electronic tag. Meanwhile, since the present invention only requires the electronic tag transmitting pair to send broadcast signals according to a predetermined transmission time slot, without requiring the transmitting pair to maintain the continuity of the signal phase, it can be compatible with tag devices of different protocols and models.

[0012] In summary, the present invention determines the position of electronic tags by measuring the distance difference between each electronic tag, which can efficiently and accurately determine the position of the electronic tags. Attached Figure Description

[0013] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. In the drawings: Figure 1 This is a schematic flowchart of the phase-based neighbor ranging and positioning method in an embodiment of the present invention; Figure 2 This is a schematic diagram of electronic tag grouping in an embodiment of the present invention; Figure 3 This is a schematic diagram of electronic tag grouping in another embodiment of the present invention; Figure 4 This is a schematic diagram illustrating the neighbor phase measurement principle in an embodiment of the present invention; Figures 5a-5b This is a schematic diagram of the electronic tag group launch sequence in an embodiment of the present invention; Figures 6a-6d This is a schematic diagram of the launch sequence of the odd / even channel and the odd / even shelf in an embodiment of the present invention; Figure 7 This is a schematic diagram of air interface timing scheduling in an embodiment of the present invention; Figure 8 This is a schematic diagram of the electronic tag layout in an embodiment of the present invention; Figure 9 This is a schematic diagram showing the layout of Rx4 in different rows in an embodiment of the present invention; Figure 10 This is a schematic diagram illustrating the mapping relationship between phase features and distance difference in an embodiment of the present invention; Figure 11 This is a schematic diagram of electronic tag ranging grouping in an embodiment of the present invention; Figure 12 This is a schematic diagram illustrating the changes in electronic tag ranging groups in an embodiment of the present invention; Figure 13 This is a schematic diagram of a warehouse rack in an embodiment of the present invention; Figure 14 This is a schematic diagram of the label position in an embodiment of the present invention; Figure 15 This is a schematic diagram of the phase-based neighbor ranging and positioning server in an embodiment of the present invention; Figure 16 This is a flowchart illustrating a phase-based neighbor ranging and positioning method according to another embodiment of the present invention. Figure 17 This is a schematic diagram of the structure of a phase-based neighbor ranging and positioning server in another embodiment of the present invention; Figure 18This is a flowchart illustrating a phase-based neighbor ranging and positioning method according to another embodiment of the present invention. Figure 19 This is a schematic diagram of the structure of a phase-based neighbor ranging and positioning server in another embodiment of the present invention; Figure 20 This is a schematic flowchart of a phase-based neighbor ranging and positioning method in another embodiment of the present invention; Figure 21 This is a schematic diagram of the structure of a phase-based neighbor ranging and positioning server in another embodiment of the present invention; Figure 22 This is a schematic flowchart of a phase-based neighbor ranging and positioning method in another embodiment of the present invention; Figure 23 This is a schematic diagram of the phase-based neighbor ranging and positioning server in another embodiment of the present invention. Detailed Implementation

[0014] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the embodiments of the present invention will be further described in detail below with reference to the accompanying drawings. Here, the illustrative embodiments of the present invention and their descriptions are used to explain the present invention, but are not intended to limit the present invention.

[0015] The acquisition, storage, use, and processing of data in this application comply with relevant laws and regulations.

[0016] Considering the technical problems existing in current ranging and positioning schemes, this invention mainly proposes a phase-based neighbor ranging and positioning scheme. This scheme uses the phase of multiple frequency points for distance measurement to accurately determine the location of electronic tags. The phase-based neighbor ranging and positioning scheme is described in detail below.

[0017] Figure 1 This is a schematic flowchart of the phase-based neighbor ranging and positioning method in an embodiment of the present invention. This phase-based neighbor ranging and positioning method can be applied to the positioning server mentioned below, such as... Figure 1 As shown, the method includes the following steps: Step 101: Send a neighbor phase measurement command to schedule the electronic tag transmitting pairs in the scene to be located to transmit broadcast signals in a pre-set time sequence according to the pre-allocated time sequence, wherein each shelf aisle in the scene to be located includes at least one pair of electronic tag transmitting pairs; Step 102: After all electronic tag transmitting pairs in the scene to be located have completed the broadcast signal transmission, receive the neighbor phase measurement results sent by the electronic tags in the scene to be located; Step 103: Based on the received neighbor phase measurement results, divide the electronic tags in the scene to be located into multiple phase difference operation groups, and calculate the distance difference between each electronic tag in each group by means of phase difference operation. Each phase difference operation group includes at least one pair of electronic tag transmission pairs, and the other electronic tags in the group are electronic tags that receive the broadcast signal of the electronic tag transmission pair. Step 104: Based on the known positions of the anchor point electronic tags in the scene to be located, and the calculated distance differences between each electronic tag in each phase difference operation group, determine the position of the electronic tag to be located in the scene to be located.

[0018] The beneficial technical effects of the phase-based neighbor ranging and localization method provided in this embodiment of the invention are: Firstly, in existing technologies, each positioning operation only measures the distance between pairs of electronic tags, resulting in low efficiency. Furthermore, traditional electronic tag signal ranging schemes rely on bidirectional signal transmission and reception, leading to cumbersome and time-consuming measurement processes. To address this issue, the phase-based neighbor ranging positioning scheme provided in this invention issues a neighbor phase measurement command to schedule pre-defined electronic tag transmitting pairs in the positioning scenario to sequentially transmit broadcast signals according to a pre-allocated time sequence. Each shelf aisle in the positioning scenario includes at least one electronic tag transmitting pair. After all electronic tag transmitting pairs in the positioning scenario have completed their broadcast signal transmission, the neighbor phase measurement results sent by each electronic tag in the positioning scenario are received. This allows for rapid collection of phase measurement results from tags in the positioning scenario, and the electronic tags in the positioning scenario do not need to all undertake the role of broadcast signal transmission, improving measurement efficiency. This invention eliminates the need for bidirectional signal transmission and reception, making it faster, more robust, and more compatible.

[0019] Secondly, in existing technologies, the bidirectional transceiver mode is susceptible to channel interference and differences in tag device response, resulting in insufficient robustness of phase measurement results. Furthermore, it suffers from poor compatibility with different protocols and tag device models, leading to high adaptation costs. To address this issue, the phase-based neighbor ranging and positioning scheme provided in this invention divides all electronic tags in the target location scenario into multiple phase differential operation groups based on the received neighbor phase measurement results. The distance difference between each electronic tag in each group is calculated using phase differential operations. Each phase differential operation group includes at least one pair of electronic tag transmitters, and the other electronic tags in the group are those that received the broadcast signal from that pair. Based on the known positions of anchor electronic tags in the target location scenario and the calculated distance differences between each electronic tag in each phase differential operation group, the position of the electronic tag to be located in the target location scenario is determined. Determining the position of the electronic tag through the distance differences between each electronic tag can offset common errors, such as common channel delays and inherent device biases, thereby improving the positioning accuracy of the electronic tag. Meanwhile, since the present invention only requires the electronic tag transmitting pair to send broadcast signals according to a predetermined transmission time slot, without requiring the transmitting pair to maintain the continuity of the signal phase, it can be compatible with tag devices of different protocols and models.

[0020] In summary, the present invention determines the position of electronic tags by measuring the distance difference between each electronic tag, which can efficiently and accurately determine the position of the electronic tags.

[0021] This invention relates to the field of wireless positioning technology, and more particularly to a method for obtaining the location of electronic tags. It mainly includes a method for obtaining neighbor phase information, a positioning method based on neighbor phase, and a method for batch tag interference avoidance and efficient neighbor phase measurement. These will be described in detail below.

[0022] In this embodiment of the invention, the electronic tag is a signal source capable of transmitting broadcast signals, such as an electronic shelf tag.

[0023] In step 101 above, each shelf aisle in the scene to be located includes at least one pair of electronic tag transmitters. Preferably, each shelf includes at least one pair of electronic tag transmitters to ensure that the electronic tags in the scene to be located can receive more broadcast signals.

[0024] In step 101 above, the broadcast signal transmission power of the electronic tag can be configured based on the actual situation. By configuring different transmission powers, the coverage range of the electronic tag broadcast signal can be adjusted.

[0025] In step 101 above, the electronic tags in the same shelf aisle in this embodiment of the invention can be electronic tags on shelves on both sides of the same shelf aisle.

[0026] In step 101 above, in this embodiment of the invention, the electronic tag transmitting pair can be the electronic tag that is determined to transmit a broadcast signal in each round of positioning.

[0027] In step 101 above, the scene to be located in the implementation of the present invention can be the entire supermarket scene, a certain area in the supermarket that needs to be located, or a scene such as a pharmacy.

[0028] In step 101 above, the electronic tag transmitting pairs that are pre-set as transmitters in the scenario to be located are scheduled to transmit broadcast signals in sequence according to a pre-allocated time sequence, which may include: the electronic tag transmitting pairs that are pre-set as transmitters in the scenario to be located are scheduled to transmit broadcast signals in sequence on at least two frequency points according to a pre-allocated time sequence.

[0029] In practice, the accuracy of electronic tag positioning can be further improved by using the phase measurement results of neighboring nodes at multiple frequencies.

[0030] In one embodiment, the broadcast signal may be a Bluetooth broadcast signal, etc.

[0031] In one embodiment, during step 101 above, when one of the electronic tags in an electronic tag transmitting pair transmits a broadcast signal, the other electronic tags in the same shelf aisle are in a non-transmitting state.

[0032] In one embodiment, during step 101 above, when one of the electronic tags in an electronic tag transmitting pair transmits a broadcast signal, the remaining electronic tags in the same shelf aisle, as well as at least the electronic tags in adjacent shelf aisles of the shelf aisle where the electronic tag transmitting pair is located, are in a non-transmitting state.

[0033] In practice, under normal circumstances, in order to ensure the comprehensive positioning of the electronic tags in the scene to be located, all the electronic tags that are not in the transmitting state should be in the receiving state. However, under certain specific circumstances, some electronic tags may also be in the dormant state.

[0034] In step 101 above, scheduling electronic tag transmitters, pre-selected as transmitters in the scene to be located, to sequentially transmit broadcast signals on at least two frequencies according to a pre-allocated timing sequence may include: After all electronic tag transmitters in the scene to be located have completed broadcast signal transmission on one frequency point, they switch to the next frequency point. All electronic tag transmitters in the scene to be located then broadcast signal transmission on the next frequency point until all electronic tag transmitters in the scene to be located have completed broadcast signal transmission on all frequency points. Alternatively, the electronic tags can be divided into multiple groups according to the shelf aisles. After the electronic tag transmitters in one group have completed the broadcast signal transmission on all frequencies, the electronic tag transmitters in the next group begin to transmit broadcast signals on all frequencies, until all electronic tag transmitters in all groups in the scene to be located have completed the broadcast signal transmission on all frequencies.

[0035] In practice, the first method of transmitting broadcast signals can be to transmit broadcast signals sequentially to all transmitting pairs in the scene to be located on one frequency point, and then to transmit broadcast signals sequentially to all transmitting pairs in the scene to be located on the next frequency point. This method can improve the efficiency of collecting neighbor phase measurement results.

[0036] In practice, the second method of transmitting broadcast signals can be to complete the transmission of broadcast signals by all electronic tag pairs in a group of electronic tags on all frequencies at one frequency point, and then proceed to the next group of electronic tag pairs to transmit broadcast signals on all frequencies. This transmission method can also improve the efficiency of collecting neighbor phase measurement results.

[0037] In step 102 above, it can be receiving neighbor phase measurement results sent by all electronic tags in the scene to be located, or it can be receiving neighbor phase measurement results sent by a portion of electronic tags in the scene to be located.

[0038] In one embodiment, the phase-based neighbor ranging and localization method described above may further include: The electronic tags in the scene to be located are divided into multiple electronic tag groups in order to eliminate interference in the middle of the signal while improving the transmission efficiency of the electronic tag broadcast signal in the scene to be located, and to assign signal transmission timing to the electronic tag transmitting pairs in each electronic tag group. During the broadcast signal transmission of the electronic tag pair in each electronic tag group, the other electronic tag groups are in a non-transmitting state. The electronic tags in the non-transmitting state should be in a receiving state. However, under certain specific circumstances, some electronic tags may also be in a dormant state.

[0039] In practical implementation, embodiments of the present invention can divide the electronic tags on the shelf in the scenario to be located into multiple electronic tag groups, coordinate the interference of tag measurement signals, and improve the positioning accuracy.

[0040] In one embodiment, dividing the electronic tags in the scene to be located into multiple electronic tag groups may include: dividing the electronic tags in the scene to be located into odd-channel electronic tag groups and even-channel electronic tag groups; during the broadcast signal transmission process of the electronic tag transmitting pairs in the odd-channel electronic tag groups or even-channel electronic tag groups, the electronic tags in the same channel as the electronic tag transmitting pairs are all in a non-transmitting state. The electronic tags in the non-transmitting state should all be in a receiving state. However, under certain specific circumstances, some electronic tags may also be in a dormant state. Electronic tag transmitting pairs in the same group that are in different channels from the electronic tag transmitting pairs may be in a transmitting state.

[0041] In practice, Figure 2 This is a schematic diagram of electronic tag grouping in an embodiment of the present invention, such as... Figure 2 As shown, embodiments of the present invention can divide the electronic tags on the shelf in the scene to be located into multiple electronic tag groups, such as odd-numbered channel electronic tag groups (e.g. Figure 2 Odd-numbered channels 1 and 3 form one electronic tag group, and even-numbered channel electronic tag groups (e.g.) Figure 2 Even-numbered channels 2 and 4 form a single electronic tag group, coordinating with the tag measurement signals to reduce interference and improve positioning accuracy. Under this division method, electronic tags can be arranged according to... Figures 5a-5b The transmission timing signal, Figures 5a-5b This is a schematic diagram of the electronic tag group launch sequence in an embodiment of the present invention.

[0042] by Figure 2 For example, the electronic tags on the shelves in odd-numbered channels 1 and 3 belong to the odd-numbered channel electronic tag group. The electronic tag transmitting pairs on the shelves in odd-numbered channels 1 and 3 in this electronic tag group can transmit broadcast signals together. Subsequently, the electronic tag transmitting pairs on the shelves in even-numbered channels 2 and 4 in the even-numbered channel electronic tag group can also transmit broadcast signals together. This achieves the goal of avoiding co-frequency interference between signals from different transmitting pairs by combining spatial isolation and time slot separation, thereby improving signal transmission quality and ultimately improving the accuracy of the final positioning result.

[0043] In one embodiment, the electronic tags in the scene to be located are divided into multiple electronic tag groups, including: dividing the electronic tags in the scene to be located into odd-numbered shelf group electronic tag group with odd-numbered aisles, even-numbered shelf group electronic tag group with odd-numbered aisles, odd-numbered shelf group electronic tag group with even-numbered aisles, and even-numbered shelf group electronic tag group with even-numbered aisles.

[0044] In practice, for example, all shelves in odd-numbered aisles can be divided into five shelf groups, including the first shelf group, the second shelf group, the third shelf group, the fourth shelf group, and the fifth shelf group arranged from left to right. The odd-numbered shelf groups in odd-numbered aisles include the first shelf group, the third shelf group, and the fifth shelf group. The first shelf group can include only the first shelf or multiple consecutive shelves, such as the first shelf and the second shelf. The number of shelves in each shelf group is not limited here. Other shelf groups are also composed based on this rule, and will not be explained again.

[0045] In practice, Figure 3 This is a schematic diagram of electronic tag grouping in another embodiment of the present invention, such as... Figure 3 As shown, the positioning server, based on the latest location information of the electronic tags, divides the electronic tags on the shelves in the scene to be located into four groups: odd-numbered shelf groups with odd-numbered channels, even-numbered shelf groups with odd-numbered channels, even-numbered shelf groups with even-numbered channels, and even-numbered shelf groups with even-numbered channels. It then assigns a signal transmission sequence to the transmitting electronic tag pairs in each group and schedules the base station to issue neighbor phase measurement commands, thereby scheduling the electronic tags in the scene to be located to perform neighbor phase measurements according to the assigned sequence. The transmitting pairs of electronic tags in the above four types of electronic tag groups transmit signals sequentially. Electronic tags not in their own transmission time slot are in a non-transmitting state. These non-transmitting electronic tags should be in a receiving state; however, under certain specific circumstances, some electronic tags may be in a dormant state. Taking the odd-numbered shelf group with odd-numbered channels as an example, the transmitting pairs of electronic tags in the same channel first transmit broadcast signals sequentially according to the assigned sequence, while transmitting pairs of electronic tags in different channels can be in the same transmission time slot as other odd-numbered channel electronic tag pairs according to their assigned time slots. After all electronic tag transmitting pairs in the same frequency segment have completed their transmissions in the target location scenario, they switch to the next frequency segment to transmit signals. After all frequency segments have completed their transmissions, the electronic tag transmitting pairs report the neighbor phase measurement results to the base station, which then reports them to the positioning server. The positioning server updates the electronic tag location in the target location scenario based on the collected neighbor phase measurement results. Optionally, the measurement order of the electronic tag group and frequency segments can be customized. Figure 4 This is a schematic diagram of the neighbor phase measurement principle in an embodiment of the present invention, except... Figure 4The scheme shown can also transmit broadcast signals sequentially according to each electronic tag group. For example, after the odd-numbered shelf group of the odd-numbered channel completes the transmission and reception of all frequencies, the remaining electronic tag groups then complete the transmission and reception of all frequencies in sequence. While each electronic tag group is performing the transmission and reception process of multiple frequencies within the group, the remaining electronic tag groups are in a non-transmitting state. The electronic tags in the non-transmitting state should all be in a receiving state. However, under certain specific circumstances, some electronic tags may also be in a dormant state to complete the entire neighbor phase measurement process.

[0046] by Figure 3 For example, the electronic tags on the odd-numbered shelves in odd-numbered channel 1 and the electronic tags on the odd-numbered shelves in odd-numbered channel 3 both belong to the odd-numbered shelf group electronic tag group of odd-numbered channels. The electronic tag transmitting pairs on the odd-numbered shelves in odd-numbered channels 1 and 3 of this odd-numbered shelf group electronic tag group can transmit broadcast signals together. Subsequently, the electronic tags on the shelves in each other electronic tag group will transmit broadcast signals together in sequence. This can achieve the goal of avoiding co-frequency interference between signals from different transmitting pairs by combining spatial isolation and time slot separation, thereby improving signal transmission quality and ultimately improving the accuracy of the final positioning result.

[0047] In practical implementation, embodiments of the present invention can coordinate the interference of tag measurement signals and improve positioning accuracy by grouping odd and even channels and odd and even shelves. Under this division method, electronic tags can be divided according to... Figures 6a-6d The transmission timing signal, Figures 6a-6d This is a schematic diagram of the launch sequence of the odd-even channel and the odd-even shelf in an embodiment of the present invention.

[0048] In one embodiment, the neighbor phase measurement results involved in this invention may include: the raw IQ (complex baseband signal) data of the broadcast signal received by each electronic tag or the phase correction term obtained based on the raw IQ data.

[0049] In practice, if the neighbor phase measurement results include a phase correction item, the electronic tag itself processes the raw IQ data into a phase correction item, reducing the amount of data uploaded to the server and thus alleviating server load. The phase correction item can be the phase of the IQ data after frequency offset compensation.

[0050] In practice, the raw IQ data is obtained by sampling from the broadcast signal.

[0051] In specific implementation, the broadcast signal may include the ID of the electronic tag that transmits the broadcast signal, and the neighbor phase measurement result may also include: the ID information included in the broadcast signal received by each electronic tag, the reception time of the broadcast signal, the ID of the electronic tag itself as the receiving end, and / or the calculated frequency offset.

[0052] Specifically, in step 103 above, taking four electronic tags (Tx1, Tx2, Rx3, Rx4) located close to each other as an example to form a phase differential operation group, which contains two transmitters, Tx1 and Tx2, and the remaining tags always receive signals within the current measurement time slot. The measurement frequency is the 2.4GHz band, and multiple frequency points between 2402MHz and 2480MHz can be used. For example, the corresponding frequency points can be selected for measurement in steps of 1MHz or 2MHz, or multiple frequency points can be selected at non-uniform intervals. At the starting frequency, Tx1 first transmits a broadcast signal according to the allocated timing, and then Tx2 transmits a signal according to the allocated timing interval between the transmission times of Tx1 and Tx2. The broadcast signal will begin to be transmitted after the specified time. This refers to the signal transmission interval of the electronic tag transmitting pair. Tag 3 (Rx3) and Tag 4 (Rx4) both maintain reception during the measurement period. Following this process, all the required measurement frequencies are sequentially traversed to obtain phase measurement data for all frequencies.

[0053] For the data of Tx1 and Tx2 received by receivers Rx3 and Rx4, each receiver will obtain two data packets. It is necessary to estimate their frequency offset, obtain the corresponding phase information after frequency offset compensation, and obtain the accurate neighbor phase measurement results of each electronic tag in each group after frequency offset compensation.

[0054] In one embodiment, if the neighbor phase measurement result includes raw IQ data, the method further includes: calculating the frequency offset of the electronic tag in each phase difference operation group based on the number of IQ data points and the sampling time interval, to obtain a phase correction term after frequency offset compensation, wherein the phase correction term is the phase of the IQ data after frequency offset compensation. Specifically, this may include calculating the frequency offset according to the following formula:

[0055] in, This indicates the number of IQ points of the sampled complex baseband signal. The sampling time interval, As the first launching end, For the second launch terminal, As the first receiving end, As the second receiving end, Indicates the first launching end to the first receiving end The complex baseband signal received by the link, Indicates the first launching end to the first receiving end The complex baseband signal received by the link, Indicates the second launch terminal to the first receiving end The complex baseband signal received by the link. Indicates the first launching end to the second receiving end The complex baseband signal received by the link. Indicates the second launch terminal to the second receiving end The complex baseband signal received by the link, Indicates the first launching end With the first receiving end Carrier frequency offset between Indicates the second launch terminal With the first receiving end Carrier frequency offset between Indicates the first launching end With the second receiving end Carrier frequency offset between Indicates the second launch terminal With the second receiving end The carrier frequency offset between them.

[0056] In practice, calculating the frequency offset of the electronic tag in each phase difference operation group means calculating the frequency offset of the electronic tags in each phase difference operation group other than the electronic tag transmitting pair that serves as the transmitter.

[0057] In one embodiment, the frequency offset can also be calculated by an electronic tag. If calculated by an electronic tag, after the transmitters in all aisles at multiple frequency points have completed transmitting signals, the electronic tag reports its calculated frequency offset and phase correction terms, along with the ID of the received electronic tag signal, the reception time, and the electronic tag's own ID, to a phase-based neighbor ranging and positioning server. This positioning device can be as follows: Figure 4 The location server is shown in the image. Of course, if the electronic tag reports the raw IQ data, the server can calculate the frequency offset to obtain accurate phase information.

[0058] Frequency offset compensation can be performed on the original IQ data based on the number of sampling points and the sampling time interval, resulting in frequency offset compensated IQ data: The average of multiple IQ points after frequency offset compensation is used to obtain the corresponding representative IQ point data. (Taking Rx3 to Tx1 as an example, the amplitude value is) This allows us to further obtain the corresponding phase information:

[0059] As can be seen from the above formula, in specific implementation, the IQ after frequency offset compensation is normalized to obtain the normalized IQ; the normalized IQ is then averaged to obtain the averaged IQ. This is the phase correction term.

[0060] Therefore, the phase information is Similarly, the phase information of the remaining data packets can be obtained:

[0061] The resulting phase information from the multi-frequency measurements is as follows: ; Theoretically, the phase information from the receiver to the transmitter is as follows: ; in, These represent the signal propagation delay between the receiver and transmitter, respectively. By performing two differential operations on the above four phases, we can obtain: ; Therefore, the differential time can be accurately estimated using phase measurement information from multiple frequency points. (Specific estimation methods include IFFT, MUSIC algorithm, SSR method, etc., which are existing algorithms, and their principles will not be elaborated here.) Thus, the distance difference can be obtained:

[0062] in, The speed of propagation of electromagnetic waves (speed of light).

[0063] In this embodiment of the invention, a method for interference avoidance and efficient phase measurement of batch tags is as follows: Typically, there are a large number of electronic tags on the racks in the field. If only one set of transmitters is assigned and measured in each time slot, the process will consume a lot of time. Therefore, it is necessary to design a corresponding parallel phase measurement timing design to avoid interference and achieve efficient phase measurement.

[0064] Specifically, such as Figure 3 As shown, the location server first divides the shelves and aisles into odd and even categories based on map information: Secondly, based on the location collected in the initial positioning scenario or the previous positioning result, the positioning server can obtain the correspondence between the shelves and the electronic tags. The map server allocates measurement time slots through four types of electronic tag groups: "odd-numbered shelf group electronic tag group in odd-numbered channels, even-numbered shelf group electronic tag group in odd-numbered channels, odd-numbered shelf group electronic tag group in even-numbered channels, and even-numbered shelf group electronic tag group in even-numbered channels." Then, the base station schedules the electronic tags in the positioning scenario to complete the phase measurement. The specific transmission sequence is as follows: Figures 6a-6d As shown, preferably, all electronic tags will act as transmitters once during the entire measurement cycle, and as receivers the rest of the time. Electronic tags on shelves in different aisles within the same electronic tag group can simultaneously transmit broadcast signals.

[0065] By configuring the time slots and measurement sequence as described above, the phase information of electronic tags in the positioning scenario can be collected efficiently.

[0066] Generally, the allocation principles and examples of electronic tag transmitter pairs based on the above-mentioned channel and shelf location information can be extended to any store scenario. The specific steps are as follows: 1. Map Information Acquisition: Obtain a global environment map of the target deployment area, which includes the location and geometric dimensions of all shelves within the area; preferably, the global map is obtained by importing computer-aided design drawings or by on-site engineering survey.

[0067] 2. Channel Space Analysis: Based on the global environment map, one or more aisles within the area are identified and determined; the aisle is the physical space located between two rows of shelves.

[0068] 3. Launch candidate group selection: For each identified channel, perform the following operations: Identify the shelves located on both sides of the aisle.

[0069] Calculate the face-to-face overlap rate of electronic tags on both sides of the shelf in terms of spatial location.

[0070] Two electronic tags whose face-to-face overlap exceeds a preset threshold are selected as a candidate transmission pair.

[0071] As can be seen from the above, in one embodiment, the phase-based neighbor ranging and positioning may further include determining the electronic tag transmitting pairs in the same shelf aisle according to the following method: Identify the shelves located on both sides of the shelving aisle; Calculate the face-to-face overlap rate of electronic tags on both sides of the shelf in terms of spatial location; Two electronic tags whose face-to-face overlap rate exceeds a preset threshold are identified as a candidate electronic tag transmission pair.

[0072] In practice, the electronic tag transmitter pairs are selected by the server from the candidate electronic tag transmitter pairs; this can be all or a portion of them.

[0073] 4. Global Launch Role Assignment: Traverse all electronic tags in the scene to be located, and according to the selection principle in step 3, assign each electronic tag at least once as the signal transmitter of the candidate transmission pair to ensure the coverage of the location in the scene to be located.

[0074] 5. Time slot allocation to avoid interference: To allocate different signal transmission time slots to all selected candidate transmitter pairs, the allocation principle is as follows: Candidate transmit pairs located in adjacent channels must not be assigned to transmit signals simultaneously in the same time slot. This step aims to prevent co-channel interference between signals from different transmit pairs by combining spatial isolation and time slot separation.

[0075] 6. Generate and execute the timing schedule: Based on the time slot allocation results, a signal transmission timing plan table for the scenario to be located is generated; the positioning server controls each candidate transmission pair to transmit positioning signals in the specified time slot according to the timing plan table, thereby achieving effective avoidance of signal interference within the system and efficient and reliable neighbor phase measurement.

[0076] In this embodiment of the invention, an efficient air interface scheduling mechanism includes: The designed air interface scheduling mechanism is mainly for allocating the roles of transmitters and receivers within an electronic tag group, the combination relationships of transmitters, and the timing relationships of transmissions. Typically, electronic tags on standard shelves are neatly arranged, and due to the obstruction of shelves and goods, tags in different channels can generally only receive signals from each other within the same channel. Therefore, in practical scenarios, considering the interference avoidance and efficient phase measurement methods for batch tags, appropriate spatial protection intervals will be considered. Shelf channels will be divided into odd and even channels. The transmission time slots of odd-numbered channels can overlap, and the transmission time slots of even-numbered channels can overlap, but the transmission time slots of odd and even channels will be strictly staggered. That is, the transmission time slots of electronic tags with all transmitter roles within the same channel will be strictly staggered. Furthermore, within the same channel, considering a single transmission process, the roles of the transmitter and receiver cannot be changed. Therefore, shelves within the same channel are further divided into odd and even shelf pairs; that is, a pair of shelves facing each other belongs to either an odd or even shelf pair. In the same channel, the electronic tags of odd-numbered shelf pairs are designated as transmitters and transmitted sequentially according to a predetermined time slot during the same transmission process. Other electronic tags are in a non-transmitting state, and these non-transmitting electronic tags should all be in a receiving state. However, in certain specific cases, some electronic tags may also be in a dormant state. In another transmission process, the tags of even-numbered shelf pairs are designated as transmitters and transmitted sequentially according to a predetermined time slot.

[0077] Figure 7 This is a schematic diagram of air interface timing scheduling in an embodiment of the present invention, as shown below. Figure 7 As shown, the base station AP first broadcasts the frame number for initiating phase neighbor positioning via control command 1, and then completes the signal transmission of the electronic tag pairs in the odd and even shelf groups of the odd and even channels via control command 2. The entire phase measurement time period is divided into the transmission time period of the odd shelf group electronic tag group in the odd channel, the transmission time period of the even shelf group electronic tag group in the odd channel, the transmission time period of the odd shelf group electronic tag group in the even channel, and the transmission time period of the even shelf group electronic tag group in the even channel. For each transmission time period, phase measurement will be performed on multiple frequency points, where (Nf+1) represents the total number of frequency points measured. For each frequency point, each electronic tag transmission pair in the same group will transmit signals sequentially in the allocated time slot. The signal transmission interval T_guard (first signal transmission interval) between each frequency point is used to complete the frequency point switching. In addition, the transmission time interval T_inter (second transmission time interval) between two transmitting tags within the same transmission pair prevents signal overlap between the two transmitters. At the same time, the size of T_inter needs to be limited to prevent the introduction of large random phases, which would affect the ranging effect. Each tag transmits signals sequentially according to the assigned time sequence, and maintains receiving mode during its non-transmission time slot, thereby completing the neighbor phase measurement of the electronic tag in the scenario to be located.

[0078] As can be seen from the above, in one embodiment, for each frequency point, each electronic tag transmitting pair in the same electronic tag group transmits broadcast signals sequentially according to a pre-allocated timing sequence. Frequency point switching is completed between each frequency point using a first signal transmission interval. A second transmission time interval is set between the two electronic tags in each electronic tag transmitting pair to prevent signal overlap between the two electronic tags in the transmitting pair.

[0079] In this embodiment of the invention, the positioning method based on neighbor phase measurement is as follows: In one embodiment, each phase difference operation group includes at least four electronic tags, of which at least three are anchor electronic tags with known locations. In step 104 above, determining the position of the electronic tag to be located in the scene to be located, based on the known positions of the anchor electronic tags in the scene to be located and the calculated distance difference between each electronic tag in each phase difference operation group, may include: solving for the coordinates of the remaining electronic tags with unknown positions using the following method: A first difference equation is established, consisting of the distance difference between the remaining electronic tags at unknown positions in the first phase difference operation group and the anchor electronic tags in the first phase difference operation group. When the remaining electronic tags at the unknown location participate in the calculation of the second phase difference operation group, a second difference equation is established, which is composed of the distance difference between the remaining electronic tags at the unknown location in the second phase difference operation group and the anchor electronic tags in the second phase difference operation group. Solve the system of equations 1 and 2 simultaneously to find the coordinates of the remaining electronic tags at the unknown locations.

[0080] In practice, there are usually multiple anchor electronic tags. Even in special cases where the number of anchor electronic tags is small, as long as there are three anchor electronic tags with known locations in a group, the coordinates of the remaining electronic tags in the group can be accurately calculated. The remaining electronic tags can also be used as anchor electronic tags for this positioning and grouped with other electronic tags to calculate the accurate locations of more electronic tags. By repeating the above method multiple times, the positions of all electronic tags in the entire scene to be located can be calculated.

[0081] In practice, Figure 8 This is a schematic diagram of the electronic tag layout in an embodiment of the present invention, such as... Figure 8 As shown, for M Electronic tags (e.g.) Figure 8The measurement results of a phase difference operation group (Tx1, Tx2, Rx3, Rx4, Tx5, Tx6) can be used to perform phase difference operations on subgroups of four (each subgroup must contain two Tx tags) to obtain the distance difference between them. Each subgroup has at least three anchor points (e.g., Tx1, Tx2, Rx3), where Tx1 and Tx2 are electronic tag transmitting pairs. When the positions of the anchor electronic tags are precisely known (meaning their specific coordinates on the map are known), the distance difference between the electronic tag Rx4 (the fourth electronic tag) at an unknown location in the subgroup and the two anchor electronic tags at the transmitting end can be calculated.

[0082] Similarly, when Rx4 participates in phase measurement in other phase measurement groups or in the same group's transmit / receive conversion for phase measurement, a distance difference result between dimensions can be obtained. By combining these distance difference results, the precise location of the unknown electronic tag Rx4 can be solved. The first and second difference equations are shown in the formula above. Figure 8 As shown, assuming that Rx3 and Rx4 have collected the signals emitted by the other electronic tags Tx5 and Tx6, then solving the following system of equations will yield the accurate distance difference information between them:

[0083] The accurate location coordinates of the Rx4 (the fourth electronic tag, i.e., the second receiver) can be obtained based on the distance difference information. Optionally, considering the noise of the wireless signal, the coordinates may be offset to non-shelf areas due to errors. In this case, a aggregation operation can be performed to aggregate them to the nearest shelf.

[0084] In one embodiment, each phase difference operation group includes at least four electronic tags, of which at least three are anchor electronic tags with known locations. In step 104 above, determining the position of the electronic tag to be located in the scene to be located, based on the known positions of the anchor electronic tags in the scene to be located and the calculated distance difference between each electronic tag in each phase difference operation group, may include: solving for the coordinates of the remaining electronic tags with unknown positions using the following method: Using at least two phase difference operation groups, the position of the remaining electronic tags at unknown locations is calculated by finding the intersection of hyperbolas.

[0085] In practical implementation, besides determining the coordinates of the electronic tag by simultaneously solving the two difference equations mentioned above, the final coordinates of the remaining electronic tags at the unknown location can also be calculated using the hyperbolic positioning algorithm described above. Each phase difference operation group contains anchor tags, and at least two phase difference operation groups can be used to accurately calculate the position of electronic tags at unknown locations by finding the intersection of hyperbolas. Furthermore, when the precise coordinates of the anchor electronic tags cannot be obtained, such as when only the shelf where the electronic tag is located is known, adjacency can be determined based on the measurement results. Based on this, the embodiments of the present invention also provide the following method for determining the shelf location of electronic tags.

[0086] Option 1 Figure 9 This is a schematic diagram of Rx4 located in different row layouts in an embodiment of the present invention, such as... Figure 9 As shown, the two transmitters are located on different shelves, and the distance difference is measured. The positive and negative signs can clearly distinguish the shelf where the electronic tag is located (that is, when Rx4 is located on the upper shelf and the lower shelf, the signs of the distance difference result are exactly opposite). Then, based on the magnitude of the distance difference, it can be determined which shelf section the electronic tag Rx4 in the unknown location is located on.

[0087] As can be seen from the above, in one embodiment, the phase-based neighbor ranging and localization method includes: Obtain the row layout of the anchor electronic tag in the phase difference operation group, and determine the row layout of the electronic tag at the unknown position by the positive or negative relationship of the distance difference between the electronic tag at the unknown position and the anchor electronic tag. Based on the distance difference between each electronic tag, determine which shelf section of the shelf the electronic tag in the unknown location is located on.

[0088] In practice, the difference in distance between each electronic tag can be used to determine which shelf section of the shelf a tag with an unknown location is on.

[0089] Option 2: In the initial stage, by combining map information and collecting the real location of electronic tags by marking points, a mapping relationship between the distance difference between different tags and the corresponding shelf is constructed. This mapping relationship serves as the basis. When the corresponding distance difference is obtained, the shelf information of the tag can be obtained by comparing it with the mapping relationship table.

[0090] As can be seen from the above, in one embodiment, the phase-based neighbor ranging and localization method includes: Obtain the distance difference between each electronic tag in each phase difference operation group; The distance difference relationship between the electronic tags to be located is determined based on the distance difference between each electronic tag. Based on the distance difference between the electronic tags to be located, and the pre-established mapping relationship between the distance difference between different tags and the assigned shelf, the shelf to which the electronic tag to be located belongs is determined.

[0091] Option 3: Due to multipath effects and limited clock accuracy in real-world environments, phase measurements are often accompanied by errors. Therefore, fingerprint matching can be optionally used for distance measurement and location determination. Specifically, in the initial stage, the real-world locations of the electronic tags in the scene to be located are collected, and the tags are grouped for measurement. Typically, two tags opposite the shelf act as transmitters, while the others receive signals, thus collecting the phase measurement results of the tags in the scene to be located. Secondly, phase difference features at multiple frequencies or dimensionality-reduced features (such as spectral peak positions) processed by IFFT / MUSIC algorithms are extracted, thus establishing a... Figure 10 The mapping relationship between the features shown and the actual distance difference is as follows: Figure 10 This is a schematic diagram illustrating the mapping relationship between phase features and distance difference in an embodiment of the present invention. When the corresponding phase measurement is completed during routine positioning, similarity matching is performed based on phase features or dimensionality reduction features, and the result with the highest matching degree is the current distance measurement result. Furthermore, to further enrich the feature library, the transmission time alignment can be simultaneously aligned to Tx1 and Tx2, and then the distance difference result is calculated. Specific matching methods can use the similarity of vectors or matrices composed of features for measurement, or a neural network can be used to learn the mapping relationship table and infer the distance measurement result during routine positioning.

[0092] As can be seen from the above, in one embodiment, the position of the electronic tag is further corrected according to the following method: Obtain the current neighbor phase measurement results of the electronic tag to be calibrated; Extract the current phase difference feature from the current neighbor phase measurement results; Based on the current phase difference characteristics and the pre-established relationship between historical phase difference characteristics and actual distance differences, the actual distance difference corresponding to the current phase difference characteristics is obtained; Based on the actual distance difference corresponding to the current phase difference characteristics, the correction position of the electronic tag to be corrected is obtained.

[0093] In one embodiment, the phase-based neighbor ranging and localization method further includes: After processing the historical phase difference features using a preset dimensionality reduction algorithm, the historical dimensionality-reduced phase difference features are obtained. Establish the relationship between historical phase difference characteristics and actual distance difference.

[0094] In practice, the historical phase difference features are processed by a preset dimensionality reduction algorithm to obtain the historical dimensionality-reduced phase difference features. Then, the relationship between the historical dimensionality-reduced phase difference features and the pre-measured actual distance difference is established, which can improve matching efficiency and thus improve positioning efficiency.

[0095] The specific steps of the positioning method in Scheme 3 above are as follows: 1. In the offline fingerprint database construction phase, the data used in this phase, such as phase difference feature data, can be historical data.

[0096] Baseline location information collection. After the positioning scenario is deployed, the actual physical location coordinates of each electronic tag in the scene to be positioned are collected, and a unique identifier (ID) is assigned to it.

[0097] Group measurement and phase data collection. Electronic tags in the scene to be located are grouped. Preferably, two electronic tags located on opposite sides of a shelf are configured as signal transmitters, i.e., electronic tag transmitting pairs, such as Tx1 and Tx2, and the remaining electronic tags are configured as signal receivers, such as Rx1 and Rx2. The transmitters are controlled to transmit wireless signals sequentially or concurrently. Each receiver receives and measures the phase information of the signals from different transmitters, thereby collecting multiple sets of phase measurement results among the electronic tags in the scene to be located. The implementation of this section can be found in the relevant description of phase measurement and result collection in the previous embodiments.

[0098] Feature extraction. Feature extraction is performed on the collected raw phase measurement results. The features include, but are not limited to: a) Phase difference characteristics (which can be multi-frequency phase difference characteristics): directly using the difference or linear combination of phase values ​​measured at different frequencies; b) Dimensionality reduction features: Key features extracted after transforming multi-frequency phase difference feature data through signal processing algorithms, such as the time-domain spectral peak position obtained by the inverse fast Fourier transform algorithm, or the spatial spectral peak position obtained by the multiple signal classification algorithm.

[0099] Construct a mapping relationship database. Based on the collected real location coordinates, calculate the actual distance difference from each receiver to the two transmitters (Tx1, Tx2). The phase features or dimensionality-reduced features extracted in the feature extraction step are correlated with the calculated actual distance difference to establish a relationship between historical phase difference features and actual distance difference. This relationship can be a mapping relationship or a neural network model, thereby forming an offline fingerprint database for subsequent matching.

[0100] Preferred feature database enhancement scheme: To enrich the feature diversity of the fingerprint database, a transmission time alignment operation can be performed when performing group measurement and phase data collection steps: The receiver is synchronized with the transmitters Tx1 and Tx2 respectively, and two sets of phase measurement results are calculated based on different time alignment benchmarks, and then the corresponding features are extracted and stored in the fingerprint database.

[0101] 2. In the online positioning phase, the phase difference characteristics and other related data used in this phase can be real-time data (e.g., current phase difference characteristics).

[0102] Real-time phase measurement. During routine positioning, when it is necessary to locate the target electronic tag, it is controlled to measure the phase difference information of the broadcast signal from the designated transmitter (Tx1, Tx2) according to the same grouping and communication protocol as in the offline stage.

[0103] Real-time feature extraction. For the measured real-time phase information, the same feature extraction method as mentioned in the offline fingerprint database construction stage can be used to obtain a real-time feature vector or matrix, that is, to extract the current phase difference feature from the current neighbor phase measurement results.

[0104] Similarity matching and distance difference estimation. The obtained real-time features (current phase difference features) are compared with the phase difference features stored in the offline fingerprint database. The distance difference between the fingerprint data with the highest matching degree is determined as the estimated real-time distance difference between the current target electronic tag and the two transmitters. In other words, the current phase difference features are matched with the relationship between historical phase difference features and actual distance differences pre-established in the offline fingerprint database construction stage to obtain the actual distance difference corresponding to the current phase difference features.

[0105] In one embodiment, if the relationship between historical phase difference features and actual distance difference is a pre-trained neural network model, then the neural network model can be called a distance difference recognition model. The input of the recognition model can be the current phase difference feature, and the output of the recognition model can be the actual distance difference corresponding to the current phase difference feature.

[0106] As can be seen from the preceding paragraph, in specific implementations, embodiments of the present invention can also be based on neural network inference. As an alternative or supplementary solution to feature matching, in the step of constructing the mapping relationship database, the offline fingerprint database can be used to train the neural network model to learn the complex mapping relationship from features to distance differences. In the online positioning stage, the extracted real-time features are input into the trained neural network model, and the model directly infers and outputs the distance difference measurement result corresponding to the current phase difference feature.

[0107] In practice, the above similarity matching can be achieved by calculating the Euclidean distance, cosine similarity, or other similarity metrics between feature vectors or matrices.

[0108] 3. Location Determination

[0109] Based on the obtained distance difference, i.e. the actual distance difference corresponding to the current phase difference feature, and combined with the known positions of the two transmitters, the final position coordinates of the electronic tag to be located can be calculated using the hyperbolic positioning algorithm or other geometric positioning algorithms.

[0110] In this embodiment of the invention, the method for determining the movement and updating the location of electronic tags is as follows: In one embodiment, the above-described phase-based neighbor ranging and positioning method may further include a method for determining whether the electronic tag has moved: Obtain the ID of the electronic tag received by each electronic tag in the current positioning round; The ID of the electronic tag received by each electronic tag in the current positioning round is compared with the ID of the electronic tag received by the same electronic tag in the previous positioning round to obtain the ID duplication rate. If the ID duplication rate is lower than a preset threshold, it is determined that the electronic tag has been moved.

[0111] In practice, the ID of the electronic tag received by each electronic tag in the current positioning round is obtained; the ID of the electronic tag received by each electronic tag in the current positioning round is compared with the ID of the electronic tag received by the same electronic tag in the previous positioning round to obtain the ID repetition rate; if the ID repetition rate is lower than a preset threshold, it is determined that the electronic tag has been moved, which can improve the accuracy of whether the electronic tag has been moved.

[0112] In one embodiment, the phase-based neighbor ranging and positioning method described above may further include: using tags that are determined not to have been moved as anchor electronic tags, and if an electronic tag that is determined to have been moved has been pre-set as a transmitter, then setting its transmitted broadcast signal to invalid.

[0113] In practice, if an electronic tag with a transmitter identity is identified as moving during the neighbor phase measurement process, the signal it sends that is received by other electronic tags cannot participate in the phase measurement calculation. In other words, the neighbor phase measurement of the moving electronic tag is invalid.

[0114] For electronic tags that need to be located in a new position, the system first selects the tag pair that has not moved and has the most complete signal based on the received signals. If multiple pairs of transmitted signals are relatively complete, the system starts calculating from the pair with the most complete signal, and after iterating through multiple pairs, it obtains the position with the highest probability.

[0115] Since each transmitter corresponds to data from multiple frequency points, if the receiver receives pairs of data from a certain threshold number of frequency points or more, the distance difference can be calculated relatively accurately using a phase neighbor-based ranging method. If there are fewer than the threshold number of frequency point data pairs, the distance difference cannot be calculated, but it can be used as a rough basis for positioning.

[0116] In one embodiment, the above-described phase-based neighbor ranging and positioning method may further include a method for determining whether the electronic tag has moved: Acquire at least one phase difference operation group into which the electronic tag is assigned in the initial stage; Obtain the standard distance difference between each electronic tag in the at least one phase difference operation group; The standard distance difference between the electronic tags in at least one phase difference operation group assigned to in the initial stage is compared with the current distance difference between the electronic tags in at least one phase difference operation group assigned to in the current positioning cycle. The electronic tag is determined to have moved based on the comparison results.

[0117] In one embodiment, the phase-based neighbor ranging and positioning method described above may further include: using tags that are determined not to have been moved as anchor electronic tags, and if an electronic tag that is determined to have been moved has been pre-set as a transmitter, then setting its transmitted broadcast signal to invalid.

[0118] In one embodiment, the above-described phase-based neighbor ranging and positioning method may further include a method for determining whether the electronic tag has moved: Acquire at least one phase difference operation group into which the electronic tag is assigned in the initial stage; Obtain the initial ID information of each electronic tag in the at least one phase difference operation group and the standard distance difference between each electronic tag; The initial ID information is compared with the current ID information of each electronic tag in at least one phase difference operation group to which the electronic tag is assigned in the current positioning round; If the number of phase difference operation groups with the same ID information is less than the preset group number threshold, determine the difference between the distance difference between each electronic tag in the current positioning round and the standard distance difference between each electronic tag in the initial stage within the phase difference operation group with the same ID information. If the difference is greater than a preset difference threshold, it is determined that the electronic tag has been moved.

[0119] In specific implementation, for example, if the preset threshold for the number of groups is four, then if there are four phase difference operation groups with the same ID information, it is determined that the electronic tag has not been moved. If there are three phase difference operation groups with the same ID information, then the difference between the distance difference between each electronic tag in the current positioning round and the standard distance difference between each electronic tag in the initial stage are compared to determine whether the electronic tag has been moved. Preferably, if the difference values ​​corresponding to the three phase difference operation groups are all greater than the preset difference threshold, it is determined that the electronic tag has been moved; otherwise, it is determined that the electronic tag has not been moved. Of course, the following methods can also be used to determine whether the electronic tag has been moved: if the sum of the differences corresponding to the three phase difference operation groups is greater than the preset threshold, it is determined that the electronic tag has been moved; or, if the average value of the differences corresponding to the three phase difference operation groups is greater than the preset threshold, it is determined that the electronic tag has been moved.

[0120] In practice, the positioning frequency can be set based on the actual situation. It can be set to locate once a day, or multiple times a day over several days.

[0121] In one embodiment, the phase-based neighbor ranging and positioning method described above may further include: using tags that are determined not to have been moved as anchor electronic tags, and if an electronic tag that is determined to have been moved has been pre-set as a transmitter, then setting its transmitted broadcast signal to invalid.

[0122] For example, such as Figure 11 and Figure 12 As shown, using ESL4 as the object to be moved, an example is given to illustrate the entire move determination method: Based on the shelf location relationships on the map, after obtaining the initial RFID tag mapping data in the initial stage, the positioning server controls the AP and RFID tags to obtain the phase data of all RFID tags at known locations. This includes the phase difference calculation group into which all RFID tags were initially assigned, and the standard distance difference between each RFID tag in each phase difference calculation group, as described below. , , , , .

[0123] Figure 11 This is a schematic diagram of electronic tag ranging grouping in an embodiment of the present invention, such as... Figure 11 As shown, the first-person perspective is from ESL4's viewpoint, and it needs to be saved. Figure 11 The three sets of distance differences marked 1, 2, and 3 are related as follows: =(Distance(ESL1,4)-Distance(ESL2,4))- (Distance(ESL1,3)-Distance(ESL2,3)); =(Distance(ESL5,4)-Distance(ESL6,4))- (Distance(ESL5,7)-Distance(ESL6,7)); =(Distance(ESL9,4)-Distance(ESL10,4))- (Distance(ESL9,11)-Distance(ESL10,11)).

[0124] Where Distance(ESL1,4) represents the distance between ESL1 and ESL4, as d mentioned in the above example, for example The same applies to the rest.

[0125] Figure 12 This is a schematic diagram illustrating the changes in electronic tag ranging groups in an embodiment of the present invention, such as... Figure 12 As shown, using ESL4's perspective as the first-person view, it is also necessary to save... Figure 12 The distance difference relationship between the two sets of points 4 and 5 is marked in the middle: =(Distance(ESL5,4)-Distance(ESL6,4))- (Distance(ESL5,8)-Distance(ESL6,8)); =(Distance(ESL9,4)-Distance(ESL10,4))- (Distance(ESL9,12)-Distance(ESL10,12)).

[0126] Save the above five sets of distance difference relationships as the basis for judgment in the actual positioning stage.

[0127] The following localization algorithm description uses ESL4 as the first-person perspective of the moving label, while other labels are those that have not moved for judgment.

[0128] 1) First, determine the integrity of the neighboring transmitted signals received by ESL4. Generally, based on the propagation characteristics of wireless signals under certain transmission power limitations, the most likely complete signals received by ESL4 originate from the electronic tags of the six adjacent racks (defined as the rack to the left, right, opposite, the racks to the left and right of the opposite rack, and the rack itself). Further racks may only receive partial frequency signals, not complete signals. Therefore, based on signal integrity, the range of the six racks where ESL4 is located can be determined first.

[0129] 2) Then, based on the distance difference DM1 (current distance difference) between ESL4 and the corresponding six-section facing shelf in the middle, and the distance difference DM2 between ESL4 and ESL1, ESL2, ESL3, the current distance difference DM3 between ESL4 and ESL5, ESL6, ESL7, the current distance difference DM3 between ESL9, ESL10, ESL11, the current distance difference DM4 between ESL5, ESL6, ESL8, and the current distance difference DM5 between ESL9, ESL10, ESL12, compared with the five sets of distance difference data in the phase difference operation group to which ESL4 was initially assigned, the most likely position of ESL4 is obtained: If ESL1, ESL2, and ESL3 do not identify it as movement, then DM1 will be directly tested through ESL4. By comparison, if the signs of the distance differences are consistent and the error is small (e.g., less than 1 meter), then it is highly likely to be located at ESL4 in the figure; If DM1 and The error is relatively large, compared with The error is small (e.g., less than 1 meter); or DM2 and The error is relatively large. If the distance difference has the same sign and is consistent with... If the error is small, then ESL4 is likely near ESL8 in the figure; If DM1 and The error is relatively large, compared with The error is small (e.g., less than 1 meter); or DM3 and The error is relatively large. If the distance difference has the same sign and is consistent with... If the error is small, then ESL4 is likely near ESL12 in the figure; If any of ESL1, ESL2, or ESL3 is judged as a move: So, DM2 directly tested via ESL4 and... Comparing the distance differences, if the signs are the same and the error is small (e.g., less than 1 meter), then it is most likely located at ESL8 in the diagram; if the signs are the same and the error is large (e.g., greater than 1 meter), then DM3, which was directly tested via ESL4, is more likely to be at the location shown. If the error is small (e.g., less than 1 meter), then it is most likely located at ESL12 in the diagram. If ESL7 is judged to be moving, and ESL8 is not moving, then DM4 can be... By comparison, if the signs of the distance differences are consistent and the error is small (e.g., less than 1 meter), then ESL4 is likely near ESL4 in the graph; As described above, the entire algorithm prioritizes finding a pair of face-to-face shelves in the six-section shelving where the positions of ESL1, ESL2, and ESL3 have not moved. By comparing the signs of the distance differences, it can be determined that the shelf position of ESL4 is consistent with that of ESL1 or ESL2; then, by comparing the absolute values ​​of the distance differences, the specific section number of ESL4 in the six-section shelving can be determined, thus completing the positioning.

[0130] As can be seen from the above, in one embodiment, the phase-based neighbor ranging and positioning may further include finding and determining the location of the moved electronic tag by the following method: Select multiple selected phase difference operation groups, including the determined moving electronic tag as the target tag; Obtain the current distance difference of each electronic tag in each selected difference operation group; The current distance difference of each electronic tag in each selected difference operation group is compared with the standard distance difference of each electronic tag in each selected difference operation group that was predetermined in the initial stage. The current position of the target label is determined based on the magnitude and sign of the error in the comparison results.

[0131] The above embodiment considers recording the position of the electronic tag at initialization, followed by tag movement detection and position updates. Throughout the process, the electronic tag itself has an inherent anchor point attribute; the immobilized electronic tag becomes the anchor point, assisting other tags in determining movement and updating their positions. In the following warehousing scenario, another embodiment will be described in conjunction with the anchor point tag situation.

[0132] For example, Figure 13 This is a schematic diagram of a warehouse rack in an embodiment of the present invention, such as... Figure 13As shown, taking the display of warehouse containers as an example, the method of placing anchor points on the containers will not change the position of the anchor points. However, the electronic tags will move in the warehouse due to warehouse operation actions such as the adjustment of goods. Therefore, for this scenario, the position of general electronic tags can be updated by using anchor points with known positions and the neighbor distance method. Specifically, taking tag 1-3 as an example, it can typically receive wireless signals from electronic tags within its adjacent 6 container sections. That is, tag 1-3 can receive signals from signal transmission pairs (anchor points 1-2, 2-2) and (anchor points 1-3, 2-3). Therefore, neighbor phase measurements can be performed according to the following ranging groups: {Tx1: Anchor point 1-2, Tx2: Anchor point 2-2, Rx1: Tag 1-3, Rx2: Anchor point 1-3}, {Tx1: Anchor point 1-3, Tx2: Anchor point 2-3, Rx1: Tag 1-3, Rx2: Anchor point 1-2}. This is a phase difference calculation group, and the distance difference between each electronic tag in each group is calculated through phase difference calculation. Note that this is not a unique combination. The ranging groups can be divided according to the following rules: each ranging group contains at least 3 anchor points; and includes a pair of face-to-face signal transmission pairs. Since all phase measurement results have been obtained during the neighbor phase measurement phase, the calculation phase only requires combining at least two equations according to the above rules to form a system of equations, which can then accurately calculate the two-dimensional position coordinates. Furthermore, when the anchor point height is known (i.e., the anchor point coordinates are two-dimensional coordinates and height information), the solution of the multiple equation systems can further support the calculation of the tag height, obtaining three-dimensional coordinates, and further supporting precise positioning at the container shelf level. Taking the two ranging groups mentioned above as examples, the anchor point positions are precisely known, therefore the positions of tags 1-3 can be accurately calculated as follows:

[0133] Furthermore, if the signals received by the electronic tags mainly come from ordinary electronic tags (such as when the available frequency of the signals collected by the electronic tag to be located from the anchor tag is below a threshold, or when no corresponding anchor tags are placed around the electronic tag to be located), then the method in the above embodiment is used. First, for ordinary electronic tags whose accurate coordinates can be calculated from the anchor tags, their confidence level is set above a certain threshold (e.g., greater than or equal to 0.8). Then, the positions of the remaining electronic tags that have not received anchor tags are located based on these electronic tags. The confidence level of the located electronic tags can be set to 0.6 in stages, forming a chain reaction, thereby obtaining the positions of all electronic tags of the warehouse containers as accurately as possible. In the next round of daily positioning, the positioning of electronic tags can still be updated based on electronic tags that have not been judged to have moved and whose confidence level is above a certain threshold.

[0134] Figure 14 This is a schematic diagram of the label position in an embodiment of the present invention, such as... Figure 14As shown, for the electronic tag transmitting pairs ESL_B and ESL_C, all other nearby electronic tags are in receive mode. The channel and distance between ESL_A and ESL_B are represented by channel b and distance b, respectively. ,in This represents the propagation time required for a wireless signal to travel from ESL_A to ESL_B or from ESL_B to ESL_A; the channel and distance between ESL_B and ESL_C are represented by channel a and a, respectively. ,in This represents the propagation time required for a wireless signal to travel from ESL_C to ESL_B or from ESL_B to ESL_C; the channel and distance between ESL_A and ESL_C are represented by channel c and distance c, respectively. ,in This indicates the propagation time required for a wireless signal to travel from ESL_C to ESL_A or from ESL_A to ESL_C.

[0135] As described above, the two electronic tag transmitting pairs transmit signals sequentially, and the electronic tags remain in receiving mode when no signal is being transmitted. Therefore, the phase correction term (PCT) (i.e., the phase of the signal) corresponding to the signal received by each electronic tag can be expressed as:

[0136] in, This indicates the PCT corresponding to the signal received by ESL_B from ESL_C. This indicates the PCT corresponding to the signal received by ESL_C from ESL_B. This indicates the PCT corresponding to the signal received by ESL_A from ESL_B. This indicates the PCT corresponding to the signal received by ESL_A from ESL_C. Indicates the first k One preset frequency point These represent the initial phases of ESL_A, ESL_B, and ESL_C, respectively. Therefore, the relationship between the aforementioned PCTs (the pre-established relationship between the phase correction terms between the electronic tags in each phase difference operation group) can be expressed as: ; Therefore, if Given that, then It can also be obtained by solving. And... The value can then be determined based on the PCT relationship between ESL_B and ESL_C (the pre-established phase correction term relationship between electronic tag transmitter pairs), i.e.: ; Therefore, once all electronic tag transmitting pairs have completed their transmissions, a receiving electronic tag can be grouped with two transmitting pairs. Within a group, knowing only the distance between the receiving tag and one of the transmitting pairs is sufficient to obtain the distances between the remaining pairs. This allows us to obtain the distances between all electronic tags that can receive signals from each other, and further use methods such as trilateration to locate the positions of all electronic tags.

[0137] As can be seen from the above, in one embodiment, the neighbor phase measurement result involved in the present invention includes: when each electronic tag receives a phase correction term of the broadcast signal, the above-mentioned phase-based neighbor ranging and positioning method may further include: Based on the received neighbor phase measurement results, the electronic tags in the scene to be located are divided into multiple phase difference operation groups. Each phase difference operation group includes at least one pair of electronic tag transmission pairs, and the other electronic tags in the group are electronic tags that have received the broadcast signal of the electronic tag transmission pair. When the distance between the electronic tag acting as the receiver and any electronic tag in the electronic tag transmitting pair is known, the distance between the electronic tag acting as the receiver and another electronic tag in the electronic tag transmitting pair in each phase difference operation group is calculated based on the pre-established phase correction term relationship between each electronic tag in each phase difference operation group. Based on the pre-established phase correction term relationship between electronic tag transmitting pairs in each phase difference operation group, the distance between electronic tag transmitting pairs in each phase difference operation group is determined; The position of the electronic tag to be located in the scene is determined based on the distance between the electronic tag acting as the receiver and any electronic tag in the electronic tag transmitting pair in each phase difference operation group, the distance between the electronic tag acting as the receiver and another electronic tag in the electronic tag transmitting pair, and the distance between the electronic tag transmitting pairs in each phase difference operation group.

[0138] exist Figure 11 , Figure 12 and Figure 14 In the image, the rectangles marked 1.09 and 35.00 on the screen represent schematic diagrams of electronic shelf labels.

[0139] This invention also provides a phase-based neighbor ranging and positioning server, as described in the following embodiments. Since the principle by which this server solves the problem is similar to that of the phase-based neighbor ranging and positioning method, the implementation of this server can refer to the implementation of the phase-based neighbor ranging and positioning method; repeated details will not be elaborated further.

[0140] Figure 15 This is a schematic diagram of the phase-based neighbor ranging and positioning server in an embodiment of the present invention, as shown below. Figure 15As shown, the server includes: The first transmitting unit 01 is used to send a neighbor phase measurement command to schedule the electronic tag transmitting pairs in the scene to be located to transmit broadcast signals in a pre-set transmitting end according to a pre-allocated time sequence, wherein each shelf aisle in the scene to be located includes at least one pair of electronic tag transmitting pairs. The first receiving unit 02 is used to receive the neighbor phase measurement results sent by the electronic tags in the scene to be located after all electronic tag transmitting pairs in the scene to be located have completed the broadcast signal transmission. The first phase difference operation unit 03 is used to divide the electronic tags in the scene to be located into multiple phase difference operation groups according to the received neighbor phase measurement results, and calculate the distance difference between each electronic tag in each phase difference operation group by means of phase difference operation. Each phase difference operation group includes at least one pair of electronic tag transmission pairs, and the other electronic tags in the group are electronic tags that receive the broadcast signal of the electronic tag transmission pair. The first positioning unit 04 is used to determine the position of the electronic tag to be positioned in the scene based on the known position of the anchor point electronic tag in the scene to be positioned and the calculated distance difference between each electronic tag in each phase difference operation group.

[0141] In one embodiment, scheduling electronic tag transmitting pairs, which are pre-set as transmitters in the scene to be located, to sequentially transmit broadcast signals according to a pre-allocated time sequence includes: scheduling electronic tag transmitting pairs, which are pre-set as transmitters in the scene to be located, to sequentially transmit broadcast signals on at least two frequency points according to a pre-allocated time sequence.

[0142] In one embodiment, scheduling electronic tag transmitting pairs, pre-defined as transmitters in a scenario to be located, to sequentially transmit broadcast signals on at least two frequencies according to a pre-allocated timing sequence includes: After all electronic tag transmitters in the scene to be located have completed broadcast signal transmission on one frequency point, they switch to the next frequency point. All electronic tag transmitters in the scene to be located then broadcast signal transmission on the next frequency point until all electronic tag transmitters in the scene to be located have completed broadcast signal transmission on all frequency points. Alternatively, the electronic tags can be divided into multiple groups according to the shelf aisles. After the electronic tag transmitters in one group have completed the broadcast signal transmission on all frequencies, the electronic tag transmitters in the next group begin to transmit broadcast signals on all frequencies, until all electronic tag transmitters in all groups in the scene to be located have completed the broadcast signal transmission on all frequencies.

[0143] In one embodiment, the neighbor phase measurement results include: raw IQ data of the broadcast signal received by each electronic tag or a phase correction term obtained based on the raw IQ data.

[0144] In one embodiment, if the neighbor phase measurement result includes raw IQ data, the method further includes: calculating the frequency offset of the electronic tag in each phase difference operation group based on the number of IQ data points and the sampling time interval, so as to obtain the phase correction term after frequency offset compensation.

[0145] In one embodiment, the phase-based neighbor ranging and positioning device described above may further include: The segmentation unit is used to divide the electronic tags in the scene to be located into multiple phase difference operation groups according to the received neighbor phase measurement results. Each phase difference operation group includes at least one pair of electronic tag transmission pairs, and the other electronic tags in the group are electronic tags that have received the broadcast signal of the electronic tag transmission pair. The first distance calculation unit is used to calculate the distance between the electronic tag serving as the receiver and another electronic tag in the electronic tag transmitting pair, based on the pre-established phase correction term relationship between each electronic tag in each phase difference operation group, when the distance between the electronic tag serving as the receiver and any electronic tag in the electronic tag transmitting pair is known. The second distance calculation unit is used to determine the distance between electronic tag transmission pairs in each phase difference operation group based on the pre-established phase correction term relationship between electronic tag transmission pairs in each phase difference operation group. The positioning calculation unit is used to determine the position of the electronic tag to be located in the scene to be located based on the distance between the electronic tag acting as the receiver and any electronic tag in the electronic tag transmitting pair in each phase difference operation group, the distance between the electronic tag acting as the receiver and another electronic tag in the electronic tag transmitting pair, and the distance between the electronic tag transmitting pairs in each phase difference operation group.

[0146] In one embodiment, each phase difference operation group includes at least four electronic tags, of which at least three are anchor electronic tags with known locations; the positioning unit is specifically used to solve for the coordinates of the remaining electronic tags with unknown locations according to the following method: A first difference equation is established, consisting of the distance difference between the remaining electronic tags at unknown positions in the first phase difference operation group and the anchor electronic tags in the first phase difference operation group. When the remaining electronic tags at the unknown location participate in the calculation of the second phase difference operation group, a second difference equation is established, which is composed of the distance difference between the remaining electronic tags at the unknown location in the second phase difference operation group and the anchor electronic tags in the second phase difference operation group. Solve the system of equations 1 and 2 simultaneously to find the coordinates of the remaining electronic tags at the unknown locations.

[0147] In one embodiment, each phase difference operation group includes at least four electronic tags, of which at least three are anchor electronic tags with known locations; the positioning unit is specifically used to: solve for the coordinates of the remaining electronic tags with unknown locations according to the following method: Using at least two phase difference operation groups, the position of the remaining electronic tags at unknown locations is calculated by finding the intersection of hyperbolas.

[0148] In one embodiment, the phase-based neighbor ranging and positioning server described above may further include: The tag group division unit is used to divide the electronic tags in the scene to be located into multiple electronic tag groups in order to eliminate signal interference between electronic tags and to assign signal transmission timing to the electronic tag transmitter pairs in each electronic tag group. The transmission control unit is used to transmit broadcast signals to the electronic tag transmitter pair in each electronic tag group while the other electronic tag groups are in a non-transmitting state. The electronic tags in the non-transmitting state should be in a receiving state, but under certain specific circumstances, some electronic tags may also be in a dormant state.

[0149] In one embodiment, the electronic tags in the scene to be located are divided into multiple electronic tag groups, including: dividing the electronic tags in the scene to be located into odd-channel electronic tag groups and even-channel electronic tag groups; during the broadcast signal transmission process of the electronic tag transmitting pairs in the odd-channel electronic tag groups or even-channel electronic tag groups, the electronic tags in the same channel as the electronic tag transmitting pairs are all in a non-transmitting state. The electronic tags in the non-transmitting state should all be in a receiving state. However, under certain specific circumstances, some electronic tags may also be in a dormant state. Electronic tag transmitting pairs in the same group that are in different channels from the electronic tag transmitting pairs can be in a transmitting state.

[0150] In one embodiment, the electronic tags in the scene to be located are divided into multiple electronic tag groups, including: dividing the electronic tags in the scene to be located into odd-numbered shelf group electronic tag group with odd-numbered aisles, even-numbered shelf group electronic tag group with odd-numbered aisles, odd-numbered shelf group electronic tag group with even-numbered aisles, and even-numbered shelf group electronic tag group with even-numbered aisles.

[0151] In one embodiment, for each frequency point, each electronic tag transmitting pair in the same electronic tag group transmits broadcast signals sequentially according to a pre-allocated timing sequence. Frequency point switching is completed between each frequency point using a first signal transmission interval. A second transmission time interval is set between the two electronic tags in each electronic tag transmitting pair to prevent signal overlap between the two electronic tags in the transmitting pair.

[0152] In one embodiment, the phase-based neighbor ranging and positioning server described above may further include a correction unit for correcting the position of the electronic tag according to the following method: Obtain the current neighbor phase measurement results of the electronic tag to be calibrated; Extract the current phase difference feature from the current neighbor phase measurement results; Based on the current phase difference characteristics and the pre-established relationship between historical phase difference characteristics and actual distance differences, the actual distance difference corresponding to the current phase difference characteristics is obtained; Based on the actual distance difference corresponding to the current phase difference characteristics, the correction position of the electronic tag to be corrected is obtained.

[0153] In one embodiment, the phase-based neighbor ranging and positioning server described above may further include: The dimension reduction processing unit is used to process the historical phase difference features through a preset dimension reduction algorithm to obtain the historical dimension-reduced phase difference features. Establish a unit to establish the relationship between historical dimensionality-reduced phase difference features and actual distance difference.

[0154] In one embodiment, the phase-based neighbor ranging and positioning server described above may further include: The row layout determination unit is used to obtain the row layout where the anchor electronic tag is located in the phase difference operation group. It calculates the distance difference between each electronic tag in each group through phase difference operation. The row layout where the electronic tag at the unknown position is located is determined by the positive or negative relationship of the distance difference between the electronic tag at the unknown position and the anchor electronic tag. The positioning shelf unit is used to determine which shelf section on the shelf a tag with an unknown location is on, based on the distance difference between the various electronic tags.

[0155] In one embodiment, the phase-based neighbor ranging and positioning server described above may further include a transmitter pair determination unit for: determining the electronic tag transmitter pairs in the same shelf aisle according to the following method: Identify the shelves located on both sides of the shelving aisle; Calculate the face-to-face overlap rate of electronic tags on both sides of the shelf in terms of spatial location; Two electronic tags whose face-to-face overlap rate exceeds a preset threshold are identified as a candidate electronic tag transmission pair.

[0156] In one embodiment, the phase-based neighbor ranging and positioning server described above may further include a first displacement determination unit, used to determine whether the electronic tag has moved according to the following method: Obtain the ID of the electronic tag received by each electronic tag in the current positioning round; The ID of the electronic tag received by each electronic tag in the current positioning round is compared with the ID of the electronic tag received by the same electronic tag in the previous positioning round to obtain the ID duplication rate. If the ID duplication rate is lower than a preset threshold, it is determined that the electronic tag has been moved.

[0157] In one embodiment, the phase-based neighbor ranging and positioning server described above may further include a second movement determination unit, used to determine whether the electronic tag has moved according to the following method: Acquire at least one phase difference operation group into which the electronic tag is assigned in the initial stage; Obtain the standard distance difference between each electronic tag in the at least one phase difference operation group; The standard distance difference between the electronic tags in at least one phase difference operation group assigned to in the initial stage is compared with the current distance difference between the electronic tags in at least one phase difference operation group assigned to in the current positioning cycle. The electronic tag is determined to have moved based on the comparison results.

[0158] In one embodiment, the aforementioned phase-based neighbor ranging and positioning server may further include a third displacement determination unit, which is used to further include the following method for determining whether the electronic tag has moved: Acquire at least one phase difference operation group into which the electronic tag is assigned in the initial stage; Obtain the initial ID information of each electronic tag in the at least one phase difference operation group and the standard distance difference between each electronic tag; The initial ID information is compared with the current ID information of each electronic tag in at least one phase difference operation group to which the electronic tag is assigned in the current positioning round; If the number of phase difference operation groups with the same ID information is less than the preset group number threshold, determine the difference between the distance difference between each electronic tag in the current positioning round and the standard distance difference between each electronic tag in the initial stage within the phase difference operation group with the same ID information. If the difference is greater than a preset difference threshold, it is determined that the electronic tag has been moved.

[0159] In one embodiment, the phase-based neighbor ranging and positioning server may further include a post-processing unit for: using tags that are determined not to have been moved as anchor electronic tags, and if an electronic tag that is determined to have been moved has been pre-set as a transmitter, setting its transmitted broadcast signal to invalid.

[0160] In one embodiment, the phase-based neighbor ranging and positioning server further includes an update unit for finding the location of the moved electronic tag as follows: Select multiple selected phase difference operation groups, including the determined moving electronic tag as the target tag; Obtain the current distance difference of each electronic tag in each selected difference operation group; The current distance difference of each electronic tag in each selected difference operation group is compared with the standard distance difference of each electronic tag in each selected difference operation group that was predetermined in the initial stage. The current position of the target label is determined based on the magnitude and sign of the error in the comparison results.

[0161] This invention also provides a phase-based neighbor ranging and positioning method, as described in the following embodiments. Since the principle behind this method is similar to the phase-based neighbor ranging and positioning method described above, the implementation of this phase-based neighbor ranging and positioning method can refer to the implementation of the phase-based neighbor ranging and positioning method described above; repeated details will not be elaborated further.

[0162] Figure 16 This is a flowchart illustrating a phase-based neighbor ranging and localization method according to another embodiment of the present invention, as shown below. Figure 16 As shown, the method includes the following steps: Step 201: Send a neighbor phase measurement command to schedule the electronic tag transmitting pairs in the scene to be located to transmit broadcast signals in a pre-set time sequence according to the pre-allocated time sequence, wherein each shelf aisle in the scene to be located includes at least one pair of electronic tag transmitting pairs; Step 202: After all electronic tag transmitting pairs in the scene to be located have completed the broadcast signal transmission, receive the neighbor phase measurement results sent by the electronic tags in the scene to be located; Step 203: Based on the received neighbor phase measurement results, divide the electronic tags in the scene to be located into multiple phase difference operation groups, and calculate the distance difference between each electronic tag in each group by means of phase difference operation. Each phase difference operation group includes at least one pair of electronic tag transmission pairs, and the other electronic tags in the group are electronic tags that receive the broadcast signal of the electronic tag transmission pair. Step 204: Obtain the row of anchor electronic tags in the phase difference operation group, and determine the row of electronic tags at unknown positions by the positive or negative relationship of the distance difference between electronic tags at unknown positions and anchor electronic tags; Step 205: Based on the distance difference between each electronic tag, determine which shelf section on the shelf the electronic tag at an unknown location is located on.

[0163] In specific implementation, such as Figure 9 As shown, the two transmitters are located on different shelves, and the distance difference between them is used to determine the results. The positive and negative signs can clearly distinguish the shelf where the electronic tag is located (that is, when Rx4 is located on the upper shelf and the lower shelf, the signs of the distance difference result are exactly opposite). Then, based on the magnitude of the distance difference, it can be determined which shelf section the electronic tag Rx4 in the unknown location is located on.

[0164] Figure 16 The schematic diagram of the positioning server corresponding to the phase-based neighbor ranging and positioning method is shown below. Figure 17 As shown, Figure 17 This is a schematic diagram of the structure of a phase-based neighbor ranging and positioning server in another embodiment of the present invention, as shown below. Figure 17 As shown, the server includes: The second transmitting unit 21 is used to send a neighbor phase measurement command to schedule the electronic tag transmitting pairs in the scene to be located to transmit broadcast signals in a pre-set transmitting end according to a pre-allocated time sequence, wherein each shelf aisle in the scene to be located includes at least one pair of electronic tag transmitting pairs. The second receiving unit 22 receives the neighbor phase measurement results sent by the electronic tags in the scene to be located after all electronic tag transmitting pairs in the scene to be located have completed the broadcast signal transmission. The second phase difference operation unit 23 is used to divide the electronic tags in the scene to be located into multiple phase difference operation groups according to the received neighbor phase measurement results, and calculate the distance difference between each electronic tag in each group by means of phase difference operation. Each phase difference operation group includes at least one pair of electronic tag transmission pairs, and the other electronic tags in the group are electronic tags that receive the broadcast signal of the electronic tag transmission pair. The row layout determination unit 24 is used to obtain the row layout where the anchor electronic tag is located in the phase difference operation group, and determine the row layout where the electronic tag at the unknown position is located by the positive or negative relationship of the distance difference between the electronic tag at the unknown position and the anchor electronic tag. The second positioning unit 25 is used to determine which shelf section of the shelf a tag with an unknown location is on based on the distance difference between each tag.

[0165] This invention also provides a phase-based neighbor ranging and positioning method, as described in the following embodiments. Since the principle behind this method is similar to the phase-based neighbor ranging and positioning method described above, the implementation of this phase-based neighbor ranging and positioning method can refer to the implementation of the phase-based neighbor ranging and positioning method described above; repeated details will not be elaborated further.

[0166] Figure 18 This is a flowchart illustrating a phase-based neighbor ranging and localization method according to another embodiment of the present invention, as shown below. Figure 18 As shown, the method includes the following steps: Step 301: Send a neighbor phase measurement command to schedule the electronic tag transmitting pairs in the scene to be located to transmit broadcast signals in a pre-set time sequence according to the pre-allocated time sequence, wherein each shelf aisle in the scene to be located includes at least one pair of electronic tag transmitting pairs; Step 302: After all electronic tag transmitting pairs in the scene to be located have completed the broadcast signal transmission, receive the neighbor phase measurement results sent by the electronic tags in the scene to be located; Step 303: Based on the received neighbor phase measurement results, divide the electronic tags in the scene to be located into multiple phase difference operation groups, and calculate the distance difference between each electronic tag in each group by means of phase difference operation. Each phase difference operation group includes at least one pair of electronic tag transmission pairs, and the other electronic tags in the group are electronic tags that receive the broadcast signal of the electronic tag transmission pair. Step 304: Determine the distance difference relationship between the electronic tags to be located based on the distance difference between each electronic tag; Step 305: Based on the distance difference relationship between the electronic tags to be located, and the pre-established mapping relationship between the distance difference relationship between different tags and the assigned shelf, determine the shelf to which the electronic tag to be located belongs.

[0167] In practice, in the initial stage, by combining map information and collecting the real location of electronic tags by marking points, a mapping relationship between the distance difference between different tags and the corresponding shelf is constructed. This mapping relationship serves as the basis. When the distance difference between the corresponding tags is estimated, the location shelf information of the tag can be obtained by comparing it with the mapping relationship table.

[0168] Figure 18 The schematic diagram of the positioning server corresponding to the phase-based neighbor ranging and positioning method is shown below. Figure 19 As shown, Figure 19 This is a schematic diagram of the structure of a phase-based neighbor ranging and positioning server in another embodiment of the present invention, as shown below. Figure 19 As shown, the server includes: The third transmitting unit 31 is used to send a neighbor phase measurement command to schedule the electronic tag transmitting pairs in the scene to be located to transmit broadcast signals in a pre-set transmitting end according to a pre-allocated time sequence, wherein each shelf aisle in the scene to be located includes at least one pair of electronic tag transmitting pairs. The third receiving unit 32 is used to receive the neighbor phase measurement results sent by the electronic tags in the scene to be located after all electronic tag transmitting pairs in the scene to be located have completed the broadcast signal transmission. The third phase difference operation unit 33 is used to divide the electronic tags in the scene to be located into multiple phase difference operation groups according to the received neighbor phase measurement results, and calculate the distance difference between each electronic tag in each group by phase difference operation. Each phase difference operation group includes at least one pair of electronic tag transmission pairs, and the other electronic tags in the group are electronic tags that receive the broadcast signal of the electronic tag transmission pair. The distance difference relationship determination unit 34 is used to determine the distance difference relationship between the electronic tags to be located based on the distance difference between each electronic tag; The shelf assignment determination unit 35 is used to determine the shelf to which the electronic tag to be positioned belongs based on the distance difference relationship between the electronic tags to be positioned and the pre-established mapping relationship between the distance difference relationship between different tags and the shelf to be assigned.

[0169] This invention also provides a phase-based neighbor ranging and positioning method, as described in the following embodiments. Since the principle behind this method is similar to the phase-based neighbor ranging and positioning method described above, the implementation of this phase-based neighbor ranging and positioning method can refer to the implementation of the phase-based neighbor ranging and positioning method described above; repeated details will not be elaborated further.

[0170] Figure 20 This is a flowchart illustrating a phase-based neighbor ranging and localization method in another embodiment of the present invention, as shown below. Figure 20 As shown, the method includes the following steps: Step 401: Send a neighbor phase measurement command to schedule the electronic tag transmitting pairs in the scene to be located to transmit broadcast signals in a pre-set time sequence according to the pre-allocated time sequence, wherein each shelf aisle in the scene to be located includes at least one pair of electronic tag transmitting pairs; Step 402: After all electronic tag transmitting pairs in the scene to be located have completed the broadcast signal transmission, receive the neighbor phase measurement results sent by the electronic tags in the scene to be located; Step 403: Obtain the current neighbor phase measurement results of the electronic tag to be located from the neighbor phase measurement results sent by each electronic tag; Step 404: Extract the current phase difference feature from the current neighbor phase measurement results; Step 405: Based on the current phase difference characteristics and the pre-established relationship between historical phase difference characteristics and actual distance differences, obtain the actual distance difference corresponding to the current phase difference characteristics; Step 406: Determine the location of the electronic tag to be located based on the actual distance difference corresponding to the current phase difference feature.

[0171] In one embodiment, the phase-based neighbor ranging and localization method further includes: After processing the historical phase difference features using a preset dimensionality reduction algorithm, the historical dimensionality-reduced phase difference features are obtained. Establish the relationship between historical phase difference characteristics and actual distance difference.

[0172] In practice, the phase difference features are processed by a preset dimensionality reduction algorithm to obtain dimensionality-reduced phase difference features. Then, a mapping relationship is established between the dimensionality-reduced phase difference features and the pre-measured actual distance difference, which can improve matching efficiency and thus improve positioning efficiency.

[0173] In practical implementation, due to multipath effects and limited clock accuracy in real-world environments, phase measurements are often accompanied by certain errors. Therefore, fingerprint matching can optionally be used for distance measurement and location determination. Specifically, in the initial stage, the real locations of electronic tags in the scene to be located are collected, and the tags in the scene are grouped for measurement. Typically, two electronic tags opposite the shelf act as transmitters, while the others act as receivers, thereby collecting the phase measurement results of the electronic tags in the scene to be located. Secondly, phase difference features at multiple frequencies or dimensionality-reduced features (such as spectral peak positions) processed by IFFT / MUSIC algorithms are extracted, thus establishing a... Figure 10 The mapping relationship between the features shown and the actual distance difference is as follows: Figure 10 This is a schematic diagram illustrating the mapping relationship between phase features and distance difference in an embodiment of the present invention. When the corresponding phase measurement is completed during routine positioning, similarity matching is performed based on phase features or dimensionality reduction features, and the result with the highest matching degree is the current distance measurement result. Furthermore, to further enrich the feature library, the transmission time alignment can be simultaneously aligned to Tx1 and Tx2, and then the distance difference result is calculated. Specific matching methods can use the similarity of vectors or matrices composed of features for measurement, or a neural network can be used to learn the mapping relationship table and infer the distance measurement result during routine positioning.

[0174] The above Figure 20 The specific steps of the positioning method shown are as follows: 1. In the offline fingerprint database construction phase, the data used in this phase, such as phase difference feature data, can be historical data.

[0175] Baseline location information collection. After the positioning scenario is deployed, the actual physical location coordinates of each electronic tag in the scene to be positioned are collected, and a unique identifier (ID) is assigned to it.

[0176] Group measurement and phase data collection. Electronic tags in the scene to be located are grouped. Preferably, two electronic tags located on opposite sides of a shelf are configured as signal transmitters, i.e., electronic tag transmitting pairs, such as Tx1 and Tx2, and the remaining electronic tags are configured as signal receivers, such as Rx1 and Rx2. The transmitters are controlled to transmit wireless signals sequentially or concurrently. Each receiver receives and measures the phase information of the signals from different transmitters, thereby collecting multiple sets of phase measurement results among the electronic tags in the scene to be located. The implementation of this section can be found in the relevant description of phase measurement and result collection in the previous embodiments.

[0177] Feature extraction. Feature extraction is performed on the collected raw phase measurement results. The features include, but are not limited to: a) Phase difference characteristics (which can be multi-frequency phase difference characteristics): directly using the difference or linear combination of phase values ​​measured at different frequencies; b) Dimensionality reduction features: Key features extracted after transforming multi-frequency phase difference feature data through signal processing algorithms, such as the time-domain spectral peak position obtained by the inverse fast Fourier transform algorithm, or the spatial spectral peak position obtained by the multiple signal classification algorithm.

[0178] Construct a mapping relationship database. Based on the collected real location coordinates, calculate the actual distance difference from each receiver to the two transmitters (Tx1, Tx2). The phase features or dimensionality-reduced features extracted in the feature extraction step are correlated with the calculated actual distance difference to establish a relationship between historical phase difference features and actual distance difference. This relationship can be a mapping relationship or a neural network model, thereby forming an offline fingerprint database for subsequent matching.

[0179] Preferred feature database enhancement scheme: To enrich the feature diversity of the fingerprint database, a transmission time alignment operation can be performed when performing group measurement and phase data collection steps: The receiver is synchronized with the transmitters Tx1 and Tx2 respectively, and two sets of phase measurement results are calculated based on different time alignment benchmarks, and then the corresponding features are extracted and stored in the fingerprint database.

[0180] 2. In the online positioning phase, the phase difference characteristics and other related data used in this phase can be real-time data (e.g., current phase difference characteristics).

[0181] Real-time phase measurement. During routine positioning, when it is necessary to locate the target electronic tag, it is controlled to measure the phase difference information of the broadcast signal from the designated transmitter (Tx1, Tx2) according to the same grouping and communication protocol as in the offline stage.

[0182] Real-time feature extraction. For the measured real-time phase information, the same feature extraction method as mentioned in the offline fingerprint database construction stage can be used to obtain a real-time feature vector or matrix, that is, to extract the current phase difference feature from the current neighbor phase measurement results.

[0183] Similarity matching and distance difference estimation. The obtained real-time features (current phase difference features) are compared with the phase difference features stored in the offline fingerprint database. The distance difference between the fingerprint data with the highest matching degree is determined as the estimated real-time distance difference between the current target electronic tag and the two transmitters. In other words, the current phase difference features are matched with the relationship between historical phase difference features and actual distance differences pre-established in the offline fingerprint database construction stage to obtain the actual distance difference corresponding to the current phase difference features.

[0184] In one embodiment, if the relationship between historical phase difference features and actual distance difference is a pre-trained neural network model, then the neural network model can be called a distance difference recognition model. The input of the recognition model can be the current phase difference feature, and the output of the recognition model can be the actual distance difference corresponding to the current phase difference feature.

[0185] As can be seen from the preceding paragraph, in specific implementations, embodiments of the present invention can also be based on neural network inference. As an alternative or supplementary solution to feature matching, in the step of constructing the mapping relationship database, the offline fingerprint database can be used to train the neural network model to learn the complex mapping relationship from features to distance differences. In the online positioning stage, the extracted real-time features are input into the trained neural network model, and the model directly infers and outputs the distance difference measurement result corresponding to the current phase difference feature.

[0186] In practice, the above similarity matching can be achieved by calculating the Euclidean distance, cosine similarity, or other similarity metrics between feature vectors or matrices.

[0187] 3. Location Determination

[0188] Based on the obtained distance difference, i.e. the actual distance difference corresponding to the current phase difference feature, and combined with the known positions of the two transmitters, the final position coordinates of the electronic tag to be located can be calculated using the hyperbolic positioning algorithm or other geometric positioning algorithms.

[0189] Embodiments of the present invention can also be based on neural network reasoning. As an alternative or supplementary solution to feature matching, in the step of constructing the mapping relationship database, the offline fingerprint database can be used to train the neural network model to learn the complex mapping relationship from features to distance differences. In the online positioning stage, the extracted real-time features are input into the trained neural network model, and the model directly infers and outputs the current distance difference measurement result.

[0190] 3. Location Determination

[0191] Based on the estimated distance difference between the two transmitters and the known positions of the two transmitters, the final position coordinates of the target electronic tag are calculated using hyperbolic positioning algorithm or other geometric positioning algorithms.

[0192] Figure 20 The schematic diagram of the positioning server corresponding to the phase-based neighbor ranging and positioning method is shown below. Figure 21 As shown, Figure 21 This is a schematic diagram of the structure of a phase-based neighbor ranging and positioning server in another embodiment of the present invention, as shown below. Figure 21 As shown, the server includes: The fourth transmitting unit 41 is used to send a neighbor phase measurement command to schedule the electronic tag transmitting pairs in the scene to be located to transmit broadcast signals in a pre-set transmitting end according to a pre-allocated time sequence, wherein each shelf aisle in the scene to be located includes at least one pair of electronic tag transmitting pairs. The fourth receiving unit 42 is used to receive the neighbor phase measurement results sent by the electronic tags in the scene to be located after all electronic tag transmitting pairs in the scene to be located have completed the broadcast signal transmission; The acquisition unit 43 is used to acquire the current neighbor phase measurement results of the electronic tag to be located from the neighbor phase measurement results sent by each electronic tag; Extraction unit 44 is used to extract the current phase difference feature from the current neighbor phase measurement result; The identification unit 45 is used to obtain the actual distance difference corresponding to the current phase difference feature based on the current phase difference feature and the pre-established relationship between the historical phase difference feature and the actual distance difference. The fourth positioning unit 46 is used to determine the position of the electronic tag to be positioned based on the actual distance difference corresponding to the current phase difference characteristics.

[0193] This invention also provides a phase-based neighbor ranging and positioning method, as described in the following embodiments. Since the principle behind this method is similar to the phase-based neighbor ranging and positioning method described above, the implementation of this phase-based neighbor ranging and positioning method can refer to the implementation of the phase-based neighbor ranging and positioning method described above; repeated details will not be elaborated further.

[0194] Figure 22 This is a flowchart illustrating a phase-based neighbor ranging and localization method in another embodiment of the present invention, as shown below. Figure 22 As shown, the method includes the following steps: Step 501: Send a neighbor phase measurement command to schedule the electronic tag transmitting pairs in the scene to be located to transmit broadcast signals in a pre-set time sequence according to the pre-allocated time sequence, wherein each shelf aisle in the scene to be located includes at least one pair of electronic tag transmitting pairs; Step 502: After all electronic tag transmitting pairs in the scene to be located have completed the broadcast signal transmission, receive the neighbor phase measurement results sent by the electronic tags in the scene to be located; Step 503: Divide the electronic tags in the scene to be located into multiple phase difference operation groups according to the received neighbor phase measurement results. Each phase difference operation group includes at least one pair of electronic tag transmission pairs, and the other electronic tags in the group are electronic tags that have received the broadcast signal of the electronic tag transmission pair. Step 504: When the distance between the electronic tag serving as the receiver and any electronic tag in the electronic tag transmitting pair is known, calculate the distance between the electronic tag serving as the receiver and another electronic tag in the electronic tag transmitting pair in each phase difference operation group according to the pre-established phase correction term relationship between each electronic tag in each phase difference operation group. Step 505: Determine the distance between electronic tag transmitting pairs in each phase difference operation group based on the pre-established phase correction term relationship between electronic tag transmitting pairs in each phase difference operation group; Step 506: Determine the position of the electronic tag to be located in the scene based on the distance between the electronic tag serving as the receiver and any electronic tag in the electronic tag transmitting pair in each phase differential operation group, the distance between the electronic tag serving as the receiver and another electronic tag in the electronic tag transmitting pair, and the distance between the electronic tag transmitting pairs in each phase differential operation group.

[0195] For example, Figure 13 This is a schematic diagram of a warehouse rack in an embodiment of the present invention, such as... Figure 13As shown, taking the display of warehouse containers as an example, the method of placing anchor points on the containers will not change the position of the anchor points. However, the electronic tags will move in the warehouse due to warehouse operation actions such as the adjustment of goods. Therefore, for this scenario, the anchor points with known positions can be used to complete the position update of general electronic tags by measuring the distance from neighbors. Specifically, taking tag 1-3 as an example, it can typically receive wireless signals from electronic tags within its adjacent 6 container sections. That is, tag 1-3 can receive signals from signal transmission pairs (anchor points 1-2, 2-2) and (anchor points 1-3, 2-3). Therefore, neighbor phase measurements can be performed according to the following ranging groups: {Tx1: Anchor point 1-2, Tx2: Anchor point 2-2, Rx1: Tag 1-3, Rx2: Anchor point 1-3}, {Tx1: Anchor point 1-3, Tx2: Anchor point 2-3, Rx1: Tag 1-3, Rx2: Anchor point 1-2}. This is a phase difference calculation group, and the distance difference between each electronic tag in each group is calculated through phase difference calculation. Note that this is not a unique combination. The ranging groups can be divided according to the following rules: each ranging group contains at least 3 anchor points; and includes a pair of face-to-face signal transmission pairs. Since all phase measurement results have been obtained during the neighbor phase measurement phase, the calculation phase only requires combining at least two equations according to the above rules to form a system of equations, which can then accurately calculate the two-dimensional position coordinates. Furthermore, when the anchor point height is known (i.e., the anchor point coordinates are two-dimensional coordinates and height information), the solution of the multiple equation systems can further support the calculation of the tag height, obtaining three-dimensional coordinates, and further supporting precise positioning at the container shelf level. Taking the two ranging groups mentioned above as examples, the anchor point positions are precisely known, therefore the positions of tags 1-3 can be accurately calculated as follows:

[0196] Furthermore, if the signals received by the electronic tags mainly come from ordinary electronic tags (such as when the available frequency of the signals collected by the electronic tag to be located from the anchor tag is below a threshold, or when no corresponding anchor tags are placed around the electronic tag to be located), then the method in the above embodiment is used. First, for ordinary electronic tags whose accurate coordinates can be calculated from the anchor tags, their confidence level is set above a certain threshold (e.g., greater than or equal to 0.8). Then, the positions of the remaining electronic tags that have not received anchor tags are located based on these electronic tags. The confidence level of the located electronic tags can be set to 0.6 in stages, forming a chain reaction, thereby obtaining the positions of all electronic tags of the warehouse containers as accurately as possible. In the next round of daily positioning, the positioning of electronic tags can still be updated based on electronic tags that have not been judged to have moved and whose confidence level is above a certain threshold.

[0197] Figure 14 This is a schematic diagram of the label position in an embodiment of the present invention, such as... Figure 14As shown, for the electronic tag transmitting pairs ESL_B and ESL_C, all other nearby electronic tags are in receive mode. The channel and distance between ESL_A and ESL_B are represented by channel b and distance b, respectively. ,in This represents the propagation time required for a wireless signal to travel from ESL_A to ESL_B or from ESL_B to ESL_A; the channel and distance between ESL_B and ESL_C are represented by channel a and a, respectively. ,in This represents the propagation time required for a wireless signal to travel from ESL_C to ESL_B or from ESL_B to ESL_C; the channel and distance between ESL_A and ESL_C are represented by channel c and distance c, respectively. ,in This indicates the propagation time required for a wireless signal to travel from ESL_C to ESL_A or from ESL_A to ESL_C.

[0198] As described above, the two electronic tag transmitting pairs transmit signals sequentially, and the electronic tags remain in receiving mode when no signal is being transmitted. Therefore, the phase correction term (PCT) (i.e., the phase of the signal) corresponding to the signal received by each electronic tag can be expressed as:

[0199] in, This indicates the PCT corresponding to the signal received by ESL_B from ESL_C. This indicates the PCT corresponding to the signal received by ESL_C from ESL_B. This indicates the PCT corresponding to the signal received by ESL_A from ESL_B. This indicates the PCT corresponding to the signal received by ESL_A from ESL_C. Indicates the first k One preset frequency point These represent the initial phases of ESL_A, ESL_B, and ESL_C, respectively. Therefore, the relationship between the aforementioned PCTs (the pre-established relationship between the phase correction terms between the electronic tags in each phase difference operation group) can be expressed as: ; Therefore, if Given that, then It can also be obtained by solving. And... The value can then be determined based on the PCT relationship between ESL_B and ESL_C (the pre-established phase correction term relationship between electronic tag transmitter pairs), i.e.: ; Therefore, once all electronic tag transmitting pairs have completed their transmissions, a receiving electronic tag can be grouped with two transmitting pairs. Within a group, knowing only the distance between the receiving tag and one of the transmitting pairs is sufficient to obtain the distances between the remaining pairs. This allows us to obtain the distances between all electronic tags that can receive signals from each other, and further use methods such as trilateration to locate the positions of all electronic tags.

[0200] Figure 22 The schematic diagram of the positioning server corresponding to the phase-based neighbor ranging and positioning method is shown below. Figure 23 As shown, Figure 23 This is a schematic diagram of the structure of a phase-based neighbor ranging and positioning server in another embodiment of the present invention, as shown below. Figure 23 As shown, the server includes: The fifth transmitting unit 51 is used to send a neighbor phase measurement command to schedule the electronic tag transmitting pairs in the scene to be located to transmit broadcast signals in a pre-set transmitting end according to a pre-allocated time sequence, wherein each shelf aisle in the scene to be located includes at least one pair of electronic tag transmitting pairs. The fifth receiving unit 52 is used to receive the neighbor phase measurement results sent by the electronic tags in the scene to be located after all electronic tag transmitting pairs in the scene to be located have completed the broadcast signal transmission; The segmentation unit 53 is used to divide the electronic tags in the scene to be located into multiple phase difference operation groups according to the received neighbor phase measurement results. Each phase difference operation group includes at least one pair of electronic tag transmission pairs, and the other electronic tags in the group are electronic tags that receive the broadcast signal of the electronic tag transmission pair. The first distance calculation unit 54 is used to calculate the distance between the electronic tag serving as the receiver and another electronic tag in the electronic tag transmitting pair in each phase difference operation group, based on the pre-established phase correction term relationship between each electronic tag in each phase difference operation group, when the distance between the electronic tag serving as the receiver and any electronic tag in the electronic tag transmitting pair is known. The second distance calculation unit 55 is used to determine the distance between electronic tag transmission pairs in each phase difference calculation group based on the phase correction term relationship between electronic tag transmission pairs that is pre-established in each phase difference calculation group. The fifth positioning unit 56 is used to determine the position of the electronic tag to be positioned in the scene to be positioned based on the distance between the electronic tag serving as the receiving end and any electronic tag in the electronic tag transmitting pair in each phase differential operation group, the distance between the electronic tag serving as the receiving end and another electronic tag in the electronic tag transmitting pair, and the distance between the electronic tag transmitting pairs in each phase differential operation group.

[0201] This invention also provides a computer device, including a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, it implements the above-described phase-based neighbor ranging and positioning method.

[0202] This invention also provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements the aforementioned phase-based neighbor ranging and positioning method.

[0203] This invention also provides a computer program product, which includes a computer program that, when executed by a processor, implements the above-described phase-based neighbor ranging and positioning method.

[0204] The beneficial technical effects of the phase-based neighbor ranging and localization scheme provided in this embodiment of the invention are: Firstly, in existing technologies, each positioning operation only measures the distance between pairs of electronic tags, resulting in low efficiency. Furthermore, traditional electronic tag signal ranging schemes rely on bidirectional signal transmission and reception, leading to cumbersome and time-consuming measurement processes. To address this issue, the phase-based neighbor ranging positioning scheme provided in this invention issues a neighbor phase measurement command to schedule pre-defined electronic tag transmitting pairs in the positioning scenario to sequentially transmit broadcast signals according to a pre-allocated time sequence. Each shelf aisle in the positioning scenario includes at least one electronic tag transmitting pair. After all electronic tag transmitting pairs in the positioning scenario have completed their broadcast signal transmission, the neighbor phase measurement results sent by each electronic tag in the positioning scenario are received. This allows for rapid collection of phase measurement results from the electronic tags in the positioning scenario, and the electronic tags to be positioned do not need to all undertake the role of broadcast signal transmission, improving measurement efficiency. This invention eliminates the need for bidirectional signal transmission and reception, making it faster, more robust, and more compatible.

[0205] Secondly, in existing technologies, the bidirectional transceiver mode is susceptible to channel interference and differences in tag device response, resulting in insufficient robustness of phase measurement results. Furthermore, it suffers from poor compatibility with different protocols and tag device models, leading to high adaptation costs. To address this issue, the phase-based neighbor ranging and positioning scheme provided in this invention divides all electronic tags in the target location scenario into multiple phase differential operation groups based on the received neighbor phase measurement results. The distance difference between each electronic tag in each group is calculated using phase differential operations. Each phase differential operation group includes at least one pair of electronic tag transmitters, and the other electronic tags in the group are those that received the broadcast signal from that pair. Based on the known positions of anchor electronic tags in the target location scenario and the calculated distance differences between each electronic tag in each phase differential operation group, the position of the electronic tag to be located in the target location scenario is determined. Determining the position of the electronic tag through the distance differences between each electronic tag can offset common errors, such as common channel delays and inherent device biases, thereby improving the positioning accuracy of the electronic tag. Meanwhile, since the present invention only requires the electronic tag transmitting pair to send broadcast signals according to a predetermined transmission time slot, without requiring the transmitting pair to maintain the continuity of the signal phase, it can be compatible with tag devices of different protocols and models.

[0206] In summary, the embodiments of the present invention determine the position of electronic tags by the distance difference between each electronic tag, which can efficiently and accurately determine the position of electronic tags.

[0207] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention can take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0208] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0209] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0210] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0211] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above descriptions are merely specific embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A phase-based neighbor ranging and localization method, characterized in that, include: Send a neighbor phase measurement command to schedule the electronic tag transmitting pairs in the scene to be located to transmit broadcast signals in a pre-set time sequence according to a pre-allocated time sequence, wherein each shelf aisle in the scene to be located includes at least one pair of electronic tag transmitting pairs; After all electronic tag transmitting pairs in the scene to be located have completed the broadcast signal transmission, the neighbor phase measurement results sent by the electronic tags in the scene to be located are received. Based on the received neighbor phase measurement results, the electronic tags in the scene to be located are divided into multiple phase difference operation groups, and the distance difference between each electronic tag in each phase difference operation group is calculated by phase difference operation. Each phase difference operation group includes at least one pair of electronic tag transmission pairs, and the other electronic tags in the group are electronic tags that receive the broadcast signal of the electronic tag transmission pair. Based on the known location of the anchor point electronic tag in the scene to be located, and the calculated distance difference between each electronic tag in each phase difference operation group, the location of the electronic tag to be located in the scene to be located is determined.

2. The method as described in claim 1, characterized in that, The method of transmitting broadcast signals sequentially in a pre-defined time sequence using electronic tag transmitting pairs that are pre-set as transmitters in a scenario to be located includes: transmitting broadcast signals sequentially in a pre-defined time sequence on at least two frequency points using electronic tag transmitting pairs that are pre-set as transmitters in a scenario to be located.

3. The method as described in claim 2, characterized in that, The system involves transmitting broadcast signals sequentially on at least two frequencies according to a pre-assigned timing sequence using electronic tag transmitters pre-selected as transmitters in a scenario to be located, including: After all electronic tag transmitters in the scene to be located have completed broadcast signal transmission on one frequency point, they switch to the next frequency point. All electronic tag transmitters in the scene to be located then broadcast signal transmission on the next frequency point until all electronic tag transmitters in the scene to be located have completed broadcast signal transmission on all frequency points. Alternatively, the electronic tags can be divided into multiple groups according to the shelf aisles. After the electronic tag transmitters in one group have completed the broadcast signal transmission on all frequencies, the electronic tag transmitters in the next group begin to transmit broadcast signals on all frequencies, until all electronic tag transmitters in all groups in the scene to be located have completed the broadcast signal transmission on all frequencies.

4. The method as described in claim 1, characterized in that, The neighbor phase measurement results include: the raw IQ data of the broadcast signal received by each electronic tag or the phase correction term obtained based on the raw IQ data.

5. The method as described in claim 4, characterized in that, If the neighbor phase measurement results include raw IQ data, the method further includes: calculating the frequency offset of the electronic tag in each phase difference operation group based on the number of IQ data points and the sampling time interval, so as to obtain the phase correction term after frequency offset compensation.

6. The method as described in claim 4 or 5, characterized in that, Also includes: Based on the received neighbor phase measurement results, the electronic tags in the scene to be located are divided into multiple phase difference operation groups. Each phase difference operation group includes at least one pair of electronic tag transmission pairs, and the other electronic tags in the group are electronic tags that have received the broadcast signal of the electronic tag transmission pair. When the distance between the electronic tag acting as the receiver and any electronic tag in the electronic tag transmitting pair is known, the distance between the electronic tag acting as the receiver and another electronic tag in the electronic tag transmitting pair in each phase difference operation group is calculated based on the pre-established phase correction term relationship between each electronic tag in each phase difference operation group. Based on the pre-established phase correction term relationship between electronic tag transmitting pairs in each phase difference operation group, the distance between electronic tag transmitting pairs in each phase difference operation group is determined; The position of the electronic tag to be located in the scene is determined based on the distance between the electronic tag acting as the receiver and any electronic tag in the electronic tag transmitting pair in each phase difference operation group, the distance between the electronic tag acting as the receiver and another electronic tag in the electronic tag transmitting pair, and the distance between the electronic tag transmitting pairs in each phase difference operation group.

7. The method as described in claim 1, characterized in that, Each phase difference operation group includes at least four electronic tags, of which at least three are anchor electronic tags with known locations. Based on the known locations of the anchor electronic tags in the scene to be located, and the calculated distance differences between the electronic tags in each phase difference operation group, the location of the electronic tag to be located in the scene to be located is determined, including: solving for the coordinates of the remaining electronic tags with unknown locations using the following method: A first difference equation is established, consisting of the distance difference between the remaining electronic tags at unknown positions in the first phase difference operation group and the anchor electronic tags in the first phase difference operation group. When the remaining electronic tags at the unknown location participate in the calculation of the second phase difference operation group, a second difference equation is established, which is composed of the distance difference between the remaining electronic tags at the unknown location in the second phase difference operation group and the anchor electronic tags in the second phase difference operation group. Solve the system of equations 1 and 2 simultaneously to find the coordinates of the remaining electronic tags at the unknown locations.

8. The method as described in claim 1, characterized in that, Each phase difference operation group includes at least four electronic tags, of which at least three are anchor electronic tags with known locations. Based on the known locations of the anchor electronic tags in the scene to be located, and the calculated distance differences between the electronic tags in each phase difference operation group, the location of the electronic tag to be located in the scene to be located is determined, including: solving for the coordinates of the remaining electronic tags with unknown locations using the following method: Using at least two phase difference operation groups, the position of the remaining electronic tags at unknown locations is calculated by finding the intersection of hyperbolas.

9. The method as described in claim 1, characterized in that, Also includes: The electronic tags in the scene to be located are divided into multiple electronic tag groups to eliminate signal interference between electronic tags, and a signal transmission timing sequence is assigned to the electronic tag transmitter pairs in each electronic tag group; While the electronic tag transmitters in each electronic tag group are transmitting broadcast signals, the other electronic tag groups are in a non-transmitting state.

10. The method as described in claim 9, characterized in that, The electronic tags in the scene to be located are divided into multiple electronic tag groups, including: dividing the electronic tags in the scene to be located into odd-channel electronic tag groups and even-channel electronic tag groups; during the broadcast signal transmission process of the electronic tag transmitting pairs in the odd-channel electronic tag group or the even-channel electronic tag group, the electronic tags in the same channel as the electronic tag transmitting pair are in a non-transmitting state, while the electronic tag transmitting pairs in different channels in the same group can be in a transmitting state.

11. The method as described in claim 9, characterized in that, The electronic tags in the scene to be located are divided into multiple electronic tag groups, including: the electronic tags in the scene to be located are divided into odd-numbered shelf groups for odd-numbered channels, even-numbered shelf groups for odd-numbered channels, odd-numbered shelf groups for even-numbered channels, and even-numbered shelf groups for even-numbered channels.

12. The method as described in claim 9, characterized in that, For each frequency point, each electronic tag transmitting pair in the same electronic tag group transmits broadcast signals sequentially according to the pre-allocated timing sequence. Frequency point switching is completed between each frequency point using a first signal transmission interval. A second transmission time interval is set between the two electronic tags in each electronic tag transmitting pair to prevent signal overlap between the two electronic tags in the transmitting pair.

13. The method as described in claim 1, characterized in that, This also includes correcting the position of the electronic tag using the following method: Obtain the current neighbor phase measurement results of the electronic tag to be calibrated; Extract the current phase difference feature from the current neighbor phase measurement results; Based on the current phase difference characteristics and the pre-established relationship between historical phase difference characteristics and actual distance differences, the actual distance difference corresponding to the current phase difference characteristics is obtained; Based on the actual distance difference corresponding to the current phase difference characteristics, the correction position of the electronic tag to be corrected is obtained.

14. The method as described in claim 13, characterized in that, Also includes: After processing the historical phase difference features using a preset dimensionality reduction algorithm, the historical dimensionality-reduced phase difference features are obtained. Establish the relationship between historical phase difference characteristics and actual distance difference.

15. The method as described in claim 1, characterized in that, Also includes: Obtain the row layout of the anchor electronic tag in the phase difference operation group, and determine the row layout of the electronic tag at the unknown position by the positive or negative relationship of the distance difference between the electronic tag at the unknown position and the anchor electronic tag. Based on the distance difference between each electronic tag, determine which shelf section of the shelf the electronic tag in the unknown location is located on.

16. The method as described in claim 1, characterized in that, It also includes determining the electronic tag transmitting pairs in the same shelf aisle according to the following method: Identify the shelves located on both sides of the shelving aisle; Calculate the face-to-face overlap rate of electronic tags on both sides of the shelf in terms of spatial location; Two electronic tags whose face-to-face overlap rate exceeds a preset threshold are identified as a candidate electronic tag transmission pair.

17. The method as described in claim 1, characterized in that, It also includes the following methods for determining whether an electronic tag has moved: Obtain the ID of the electronic tag received by each electronic tag in the current positioning round; The ID of the electronic tag received by each electronic tag in the current positioning round is compared with the ID of the electronic tag received by the same electronic tag in the previous positioning round to obtain the ID duplication rate. If the ID duplication rate is lower than a preset threshold, it is determined that the electronic tag has been moved.

18. The method as described in claim 1, characterized in that, It also includes the following methods for determining whether an electronic tag has moved: Acquire at least one phase difference operation group into which the electronic tag is assigned in the initial stage; Obtain the standard distance difference between each electronic tag in the at least one phase difference operation group; The standard distance difference between the electronic tags in at least one phase difference operation group assigned to in the initial stage is compared with the current distance difference between the electronic tags in at least one phase difference operation group assigned to in the current positioning cycle. The electronic tag is determined to have moved based on the comparison results.

19. The method as described in claim 1, characterized in that, It also includes the following methods for determining whether an electronic tag has moved: Acquire at least one phase difference operation group into which the electronic tag is assigned in the initial stage; Obtain the initial ID information of each electronic tag in the at least one phase difference operation group and the standard distance difference between each electronic tag; The initial ID information is compared with the current ID information of each electronic tag in at least one phase difference operation group to which the electronic tag is assigned in the current positioning round; If the number of phase difference operation groups with the same ID information is less than the preset group number threshold, determine the difference between the distance difference between each electronic tag in the current positioning round and the standard distance difference between each electronic tag in the initial stage within the phase difference operation group with the same ID information. If the difference is greater than a preset difference threshold, it is determined that the electronic tag has been moved.

20. The method according to any one of claims 17 to 19, characterized in that, Also includes: Tags that are determined not to have been moved will be used as anchor tags. If a tag that is determined to have been moved has been pre-set as a transmitter, its broadcast signal will be set to invalid.

21. The method as described in claim 20, characterized in that, This also includes locating the moved electronic tag using the following method: Select multiple selected phase difference operation groups, including the determined moving electronic tag as the target tag; Obtain the current distance difference of each electronic tag in each selected difference operation group; The current distance difference of each electronic tag in each selected difference operation group is compared with the standard distance difference of each electronic tag in each selected difference operation group that was predetermined in the initial stage. The current position of the target label is determined based on the magnitude and sign of the error in the comparison results.

22. A phase-based neighbor ranging and positioning server, characterized in that, include: The first transmitting unit is used to send a neighbor phase measurement command to schedule the electronic tag transmitting pairs in the scene to be located to transmit broadcast signals in a pre-set transmitting end according to a pre-allocated time sequence, wherein each shelf aisle in the scene to be located includes at least one pair of electronic tag transmitting pairs. The first receiving unit is used to receive the neighbor phase measurement results sent by the electronic tags in the scene to be located after all electronic tag transmitting pairs in the scene to be located have completed the broadcast signal transmission; The first phase difference operation unit is used to divide the electronic tags in the scene to be located into multiple phase difference operation groups according to the received neighbor phase measurement results, and calculate the distance difference between each electronic tag in each phase difference operation group by means of phase difference operation. Each phase difference operation group includes at least one pair of electronic tag transmission pairs, and the other electronic tags in the group are electronic tags that receive the broadcast signal of the electronic tag transmission pair. The first positioning unit is used to determine the position of the electronic tag to be positioned in the scene based on the known position of the anchor point electronic tag in the scene to be positioned and the calculated distance difference between each electronic tag in each phase difference operation group.

23. A computer device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the computer program, it implements the method of any one of claims 1 to 21.

24. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program that, when executed by a processor, implements the method of any one of claims 1 to 21.

25. A computer program product, characterized in that, The computer program product includes a computer program that, when executed by a processor, implements the method of any one of claims 1 to 21.

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