Label positioning method and apparatus

Abstract

Embodiments of the present application provide a tag positioning method and device, which can realize tag positioning in a large-scale tag scenario. The method is applied to an electronic tag, a state machine of the electronic tag includes a positioning state, the positioning state is used for positioning the electronic tag, and the method includes: the electronic tag receives first signaling from a reader-writer, enters the positioning state in response to the first signaling, and performs a positioning operation in the positioning state. The first signaling is used for instructing, requesting or controlling the electronic tag to enter the positioning state.

Description

Technical Field

[0001] This application relates to the field of communication technology, and in particular to tag positioning methods and apparatus. Background Technology

[0002] Currently, radio frequency identification (RFID) technology can be used to identify targets. RFID systems typically consist of an interrogator and electronic tags (TAGs). The interrogator can interact with the electronic tags to manage them. In some scenarios, electronic tags can be attached to targets, and the interrogator can locate the target by tracking the tags. Tag location can be achieved in several ways; typically, the tag sends signals to the interrogator, which then locates the tag's position based on these signals.

[0003] However, current tag positioning methods are relatively inefficient. For example, for tags without chips, the signals they send to the reader may conflict, requiring the reader to run a conflict resolution mechanism to reduce these conflicts, thus reducing the reader's tag positioning efficiency. Conversely, for tags with chips, the reader often needs to issue control commands to trigger the tag to send signals, resulting in higher signaling overhead and consequently lower positioning efficiency. Summary of the Invention

[0004] This application provides a tag positioning method and apparatus, which can achieve low-interference tag positioning in large-scale tag scenarios.

[0005] Firstly, a tag positioning method is provided, applied to an electronic tag, wherein the state machine of the electronic tag includes a positioning state, the positioning state being used to position the electronic tag, and the method includes:

[0006] The electronic tag receives a first signal from the reader, and in response to the first signal, enters a positioning state; and performs a positioning operation in the positioning state. The first signal is used to instruct, request, or control the electronic tag to enter the positioning state;

[0007] The tag positioning method provided in this application adds a positioning state to the tag's state machine. The tag can enter the positioning state under the control of the reader and perform positioning operations within it. Compared to tag positioning methods without chips, where the reader can only passively wait for modulation signals from the tag before positioning, the reader can control the tag to enter the positioning state when it needs to locate it. Thus, the tag can actively perform positioning operations after entering the positioning state. Since the timing of the tag entering the positioning state is controlled by the reader, the entry times of different tags can usually be staggered to reduce the probability of collisions between the tag's transmission signals and those of other tags. Furthermore, with reduced collisions between tag transmission signals, the reader can reduce resource consumption for collision resolution, allowing more resources to be used for tag positioning, thereby improving positioning efficiency. Compared to positioning methods with chips, the tag can actively perform positioning operations after entering the positioning state, eliminating the need for each positioning operation to be triggered by a corresponding reader command, reducing the reader's signaling overhead and thus improving positioning efficiency.

[0008] In one possible design, the positioning operation includes: the electronic tag sending a first sequence to the reader or reflecting a modulated signal to the reader.

[0009] In one possible design, the first sequence sent by the electronic tag to the reader is multiple; and / or, the modulation signal sent by the electronic tag to the reader is multiple.

[0010] With the same detection probability, the SNR of a single pulse is higher than that of a multi-pulse (multiple modulated signals) pulse. In other words, in this application, by using the multi-pulse method, the reader can detect the modulated signal even with a low SNR, which means that the reader can detect the modulated signal even when the tag is at a greater distance.

[0011] In one possible design, the first sequence includes a Gold sequence, Gray code, or CAZAC sequence. Since both the reader and the tag are aware of the location sequence (i.e., the first sequence) sent by the tag, the reader can obtain not only signal strength but also more channel information, such as phase information, by measuring the location sequence, thus aiding in calculating the location distance. When the correlation of the location sequence is good, more accurate channel information can be obtained, further improving positioning accuracy.

[0012] In addition, the tag can send location sequences multiple times, and the reader can merge and filter multiple location sequences of the tag to improve measurement accuracy.

[0013] In one possible design, the electronic tag enters a positioning state in response to a first signaling, including:

[0014] The electronic tag responds to the first signaling and enters the positioning state after a first time delay.

[0015] In one possible design, after the electronic tag enters the positioning state, the method further includes: the electronic tag exits the positioning state after a second time delay.

[0016] In one possible design, the method further includes: receiving configuration information from the reader; the configuration information includes any one or more of the following: the connection method of the logic gates, the index of the connection method of the logic gates, or the connection pattern of the logic gates, a first sequence, the index corresponding to the first sequence, the parameters associated with the first sequence, and a first time period;

[0017] The first parameter in the configuration information is carried in the fourth signaling, which includes either the first signaling or the second signaling; the second parameter in the configuration information is carried in the fifth signaling, which includes either the first signaling or the second signaling; the second signaling includes a selection command and a query command; the fourth signaling and the fifth signaling may be the same signaling or different signaling.

[0018] The first parameter is a tag-level dedicated parameter; the dedicated parameter includes parameters available to the tag during the first time period; the second parameter is a reader-level common parameter.

[0019] In one possible design, the method further includes: receiving configuration information from the reader; the configuration information includes a modulation scheme; the modulation scheme includes code division modulation and frequency modulation; when the modulation scheme is code division modulation, the configuration information further includes modulation symbols; when the modulation scheme is frequency modulation, the configuration information further includes a frequency hopping pattern; the configuration information further includes any one or more of the following: the connection method of logic gates, the index of the connection method of logic gates, or the connection pattern of logic gates, and a first time period;

[0020] The first parameter in the configuration information is carried in the fourth signaling, which includes either the first signaling or the second signaling; the second parameter in the configuration information is carried in the fifth signaling, which includes either the first signaling or the second signaling; the second signaling includes a selection command and a query command; the fourth signaling and the fifth signaling may be the same signaling or different signaling.

[0021] The first parameter is a tag-level dedicated parameter; the dedicated parameter includes parameters available to the tag during the first time period; the second parameter is a reader-level common parameter.

[0022] In one possible design, the method further includes:

[0023] The reader receives a first parameter R, which instructs the electronic tag to select a random number, wherein the random number is in the range (0, 2). R-1 The first parameter R is included in the first signaling or the second signaling.

[0024] The electronic tag responds to the first signaling and enters the positioning state after a first time delay, including: when the random number is zero, the electronic tag enters the positioning state; wherein, after receiving the first signaling, the random number is decremented by one every preset time interval.

[0025] In one possible design, a third signaling is received from the reader / writer, which is used to trigger the decrement of the random number of the electronic tag by one.

[0026] In one possible design, the first signaling includes one or more of the following messages: unicast message, broadcast message, and multicast message; the second signaling includes one or more of the following messages: unicast message, broadcast message, and multicast message; the third signaling includes one or more of the following messages: unicast message, broadcast message, and multicast message; the fourth signaling includes one or more of the following messages: unicast message, broadcast message, and multicast message; and the fifth signaling includes one or more of the following messages: unicast message, broadcast message, and multicast message.

[0027] In one possible design, the electronic tag entering the positioning state includes: the electronic tag entering the positioning state from a first state;

[0028] The electronic tag exiting the positioning state includes: the electronic tag jumping from the positioning state to a second state;

[0029] The first state includes any of the following states: ready, arbitration, response, confirmation, open, and secure; the second state includes any of the following states: ready, arbitration, response, confirmation, open, secure, and deactivated.

[0030] Secondly, this application provides a tag positioning method applied to a reader / writer. The method includes: the reader / writer determining a first signaling signal and sending the first signaling signal. The first signaling signal is used to instruct, request, or control an electronic tag to enter a positioning state; the positioning state is used to locate the electronic tag.

[0031] In one possible design, the method further includes: the reader receiving a first sequence or modulation signal from the electronic tag, and locating the electronic tag based on the first sequence or the modulation signal.

[0032] In one possible design, the first sequence received by the reader from the electronic tag is multiple; and / or, the modulation signal received by the reader from the electronic tag is multiple;

[0033] The reader locates the electronic tag based on the first sequence or the modulation signal, including:

[0034] The reader merges the multiple first sequences and locates the electronic tag based on the merging result.

[0035] Alternatively, the reader / writer may merge the multiple modulation signals and locate the electronic tag based on the merging result.

[0036] In one possible design, the first sequence includes a Gold sequence, or a Gray code, or a CAZAC sequence.

[0037] In one possible design, the method further includes: sending configuration information; the configuration information includes any one or more of the following: the connection method of the logic gates, the index of the connection method of the logic gates, or the connection pattern of the logic gates, a first sequence, the index corresponding to the first sequence, the parameters associated with the first sequence, and a first time period;

[0038] The first parameter in the configuration information is carried in the fourth signaling, which includes either the first signaling or the second signaling; the second parameter in the configuration information is carried in the fifth signaling, which includes either the first signaling or the second signaling; the second signaling includes a selection command and a query command; the fourth signaling and the fifth signaling may be the same signaling or different signaling.

[0039] The first parameter is a tag-level dedicated parameter; the dedicated parameter includes parameters available to the tag during the first time period; the second parameter is a reader-level common parameter.

[0040] In one possible design, the method further includes: sending configuration information; the configuration information includes a modulation scheme; the modulation scheme includes code division modulation and frequency modulation; when the modulation scheme is code division modulation, the configuration information further includes modulation symbols; when the modulation scheme is frequency modulation, the configuration information further includes a frequency hopping pattern. The configuration information also includes any one or more of the following: the connection method of logic gates, an index of the connection method of logic gates, or a connection pattern of logic gates, or a first time period;

[0041] The first parameter in the configuration information is carried in the fourth signaling, which includes either the first signaling or the second signaling; the second parameter in the configuration information is carried in the fifth signaling, which includes either the first signaling or the second signaling; the second signaling includes a selection command and a query command; the fourth signaling and the fifth signaling may be the same signaling or different signaling.

[0042] The first parameter is a tag-level dedicated parameter; the dedicated parameter includes parameters available to the tag during the first time period; the second parameter is a reader-level common parameter.

[0043] In one possible design, the method further includes:

[0044] Send the first parameter R to instruct the electronic tag to select a random number, the random number being in the range (0, 2). R-1 The first parameter R is included in the first signaling or the second signaling.

[0045] In one possible design, a third signaling is sent, which triggers the decrement of the random number of the electronic tag by one.

[0046] In one possible design, the first signaling includes one or more of the following messages: unicast message, broadcast message, multicast message; the second signaling includes one or more of the following messages: unicast message, broadcast message, multicast message; the third signaling includes one or more of the following messages: unicast message, broadcast message, multicast message; the fourth signaling includes one or more of the following messages: unicast message, broadcast message, multicast message; and the fifth signaling includes one or more of the following messages: unicast message, broadcast message, multicast message.

[0047] In one possible design of any of the above aspects, the configuration information is carried in a fourth signaling message, which is either a broadcast message or a unicast message.

[0048] For example, the fourth signaling may include either the first signaling or the second signaling; the second signaling may include a selection command or a query command. In other words, the fourth signaling may be either the first signaling or the second signaling, or other signaling with similar functions. The second signaling may be a selection command, a query command, or other commands.

[0049] The fourth signaling and the fifth signaling may be the same signaling or different signaling.

[0050] In one possible design of any of the above aspects, the second signaling includes a selection command and a query command.

[0051] Thirdly, this application provides a communication device, which includes a module for executing the aforementioned first aspect and any possible implementation thereof.

[0052] Fourthly, this application provides a communication device comprising: a module for executing the aforementioned second aspect and any possible implementation thereof.

[0053] Fifthly, a communication device is provided, including a processor and an interface circuit. The interface circuit is configured to receive signals from other communication devices outside the communication device and transmit them to the processor, or to send signals from the processor to other communication devices outside the communication device. The processor implements the methods of the first aspect and any possible implementation thereof through logic circuits or executable code instructions. Alternatively, the processor implements the methods of the second aspect and any possible implementation thereof through logic circuits or executable code instructions.

[0054] Sixthly, this application provides a tag positioning device, including a processor and a memory, wherein the processor and the memory are coupled, and the processor is configured to implement the methods described in the first aspect and any possible implementation thereof. Alternatively, the processor is configured to implement the methods described in the first aspect and any possible implementation thereof.

[0055] In a seventh aspect, a computer-readable storage medium is provided, which stores a computer program or instructions that, when executed, implement the methods of the first aspect or any possible implementation thereof, or implement the methods of the second aspect or any possible implementation thereof.

[0056] Eighthly, a computer program product containing instructions is provided, which, when executed, implements the methods of the first aspect and any possible implementations thereof, or implements the methods of the second aspect and any possible implementations thereof.

[0057] A ninth aspect provides a chip system including a processor and potentially a memory for implementing at least one method described in the first aspect, any possible implementation of the first aspect, the second aspect, and any possible implementation of the second aspect. The chip system may be composed of chips or may include chips and other discrete devices.

[0058] In a tenth aspect, a communication system is provided, the system comprising the apparatus described in the third aspect and the apparatus described in the fourth aspect. Attached Figure Description

[0059] Figure 1 A schematic diagram of the frame format sent by the reader / writer;

[0060] Figure 2 A flowchart illustrating the process of tag management for a reader / writer;

[0061] Figure 3 This is a schematic diagram of the state machine for the tag;

[0062] Figure 4 A schematic diagram illustrating the interaction between the reader and the tag provided in an embodiment of this application;

[0063] Figure 5 A schematic diagram illustrating the state transition of a tag provided in an embodiment of this application;

[0064] Figure 6 A schematic diagram illustrating the timing requirements for tag-reader interaction provided in this application embodiment;

[0065] Figure 7 A schematic diagram of the storage space of the tag provided in an embodiment of this application;

[0066] Figure 8 A schematic diagram of the modulation signal and noise provided in the embodiments of this application;

[0067] Figure 9 A schematic diagram of the positioning signal, modulation signal, and noise provided in the embodiments of this application;

[0068] Figure 10 This is a schematic diagram illustrating the process of SAW tag reflection modulation signal provided in the embodiments of this application;

[0069] Figure 11 This is a schematic diagram of the system architecture provided for an embodiment of this application;

[0070] Figure 12 This is a schematic diagram of the structure of the label provided in an embodiment of this application;

[0071] Figure 13 A schematic diagram illustrating the label status provided in an embodiment of this application;

[0072] Figure 14 A flowchart illustrating the tag positioning method provided in an embodiment of this application;

[0073] Figure 15 A schematic diagram illustrating the relationship between detection probability and SNR under single-pulse and multi-pulse conditions provided in this application embodiment;

[0074] Figures 16 to 24 A flowchart illustrating the tag positioning method provided in an embodiment of this application;

[0075] Figure 25This is a schematic diagram of the tag positioning device provided in an embodiment of this application. Detailed Implementation

[0076] First, the technical terms or processes involved in the embodiments of this application will be introduced:

[0077] 1-1. Active Tags: Based on their power supply method, electronic tags can be divided into passive tags, active tags, and semi-active tags. Active tags, also known as self-contained tags, contain an internal battery that provides all or part of the power to the microchip inside the tag. Active tags have a longer identification range (e.g., up to tens of meters). For example, one active reader can monitor all active tags within a 100-meter range. However, active tags have a limited lifespan (3 to 10 years) and are more expensive.

[0078] It should be noted that the power for data interaction between the tag and the reader is usually not provided by the internal battery of the active tag, but by the carrier signal sent by the reader. For example... Figure 1 The diagram illustrates the frame format sent by the reader to the tag. Before sending data, the reader sends a carrier signal to the tag. Subsequent frames include a seeker header, protocol commands, etc. After receiving the carrier signal from the reader, the tag can extract the required energy from it.

[0079] 1-2. Semi-passive tag: This type of tag includes an internal battery, which powers only certain internal circuits, such as those requiring power or those with low power consumption. Before entering operational mode, the semi-passive tag is in a dormant state, essentially a passive tag. Therefore, the battery consumes less energy and can last for several years, even up to 10 years. When the semi-passive tag enters the reader's coverage area, it is activated by the radio frequency (RF) signal emitted by the reader and enters operational mode. In some scenarios, the energy used for information exchange between the tag and the reader is primarily the energy of the RF signal transmitted by the reader; the energy of the RF signal is the RF energy. The internal battery's role is mainly to compensate for insufficient RF field strength at the tag's location; the energy of the internal battery is not converted into RF energy.

[0080] 1-3. Passive Tags: These tags do not contain a battery. Outside the reader's coverage area, the tag is in a passive state. Within the reader's coverage area, the tag extracts its power from the radio frequency signal emitted by the reader. Passive tags generally use reflection to interact with the reader. The identification distance of passive tags is approximately 10 centimeters to several meters. They are lightweight and compact, have a long lifespan, and require high reader transmission power and low power consumption in the tag's operating circuitry.

[0081] Tags can be classified in other ways as well. For example, based on the modulation method, tags can be divided into active and passive, and semi-active tags. Based on whether the stored information can be rewritten, tags can be divided into read-only tags and read-write tags. Based on the packaging form, tags can be divided into credit card tags, linear tags, paper tags, glass tube tags, round tags, and special-purpose irregularly shaped tags. Furthermore, based on whether a chip is integrated within the tag, tags can be divided into chip-embedded tags and chipless tags.

[0082] 2. Tag management process of the reader / writer

[0083] like Figure 2 As shown, in an RFID system, the reader manages one or more tags through three basic operations: Select, Inventory, and Access. During this process, the possible states of the tags are as follows: Figure 3 As shown.

[0084] The Select process is used by the reader to select tags to be stored and accessed. As one possible implementation, the reader sends a select command that can select a specific number of tags based on specified criteria.

[0085] The Inventory process is used by the reader to identify tags. For example... Figure 4 This illustrates one possible inventory process, where the reader sends an inventory command through one of four sessions to begin an inventory round. The inventory command can be, but is not limited to, a query command, a query adjust command, or a query rep command.

[0086] After the reader sends a query command (or a repeat query command or an adjustment query command), one or more tags within the reader's coverage area may respond with a response message to the query command (or the repeat query command or the adjustment query command).

[0087] As one possible implementation, tags with a time slot counter of 0 respond to received disk access commands with an acknowledgment message. The working principle of the time slot counter will be explained below.

[0088] The response message carries a 16-bit random or pseudo-random (RN16) number. Optionally, the RN16 is generated by the tag. For example, the tag generates the RN16 in response to a query command.

[0089] After detecting a response message from the tag, the reader sends an acknowledgment message (ACK) to the tag. This ACK can be used to request information from the tag, such as requesting the tag's protocol control (PC) bits, extended protocol control (XPC) bits, electronic product code (EPC), and cyclic redundancy check (CRC) bits. Optionally, the ACK includes RN16. This RN16 is the same RN16 found in the response message.

[0090] It should be noted that a single inventory operation can only be performed within one session. A session is used to distinguish the memory duration of flag bits. For example, when session 1 is selected, the tag enters state B after being read once. State B lasts for 0.5 to 5 seconds before returning to state A, and the tag in state A can be read again. When session 2 is selected, if the tag continues to receive energy after being read once, it remains in state B. When energy is depleted, the tag can return to a readable state after 2 to 80 seconds.

[0091] The Access procedure is used for communication between the reader and the tag (communication includes the reader reading from the tag or the reader writing to the tag). Each tag must first be uniquely identified before it can be accessed.

[0092] The access process corresponds to multiple commands. Among them, the communication data can be masked with RN16.

[0093] 3-1. The forward link, i.e., the link from the reader to the tag. As mentioned above, the carrier signal transmitted by the reader carries electromagnetic energy. In long-distance communication scenarios (e.g., distance greater than 1m), this electromagnetic energy attenuates with increasing transmission distance. Therefore, the coverage of the forward link is limited by factors such as the energy of the carrier signal transmitted by the reader and the power consumption of the tag's receiving and processing capabilities. Specifically, the power consumption of the tag's signal processing and protocol stack processing can reach approximately 1uW, with the majority of power consumption concentrated in the protocol stack processing unit.

[0094] 3-2. The reverse link, i.e., the link from the tag to the reader. The coverage distance of the reverse link from the tag to the reader is mainly limited by the maximum coupling loss (MCL) of the reverse link coding. The reverse link coding includes, but is not limited to, bi-phase space coding or Miller coding.

[0095] 4. State Machine

[0096] Currently, tag protocol stack processing is mainly accomplished through state machine transitions. For example... Figure 3 An example of the tag state is shown, which supports 7 states: Ready, Arbitrate, Reply, Acknowledgment, Open, Secured, and Killed.

[0097] The different states of the tag are triggered by different signaling commands from the reader / writer. For example... Figure 5 The diagram illustrates the correspondence between the signaling of the reader managing tags and the tag status transitions.

[0098] The following explains the transitions between some states:

[0099] When a tag is powered on and not deactivated, it is in the ready state. In the ready state, the tag waits for a query command. The query command carries stored parameters, a sel parameter, and a timeslot count parameter Q (Q is an integer greater than or equal to 0 and less than or equal to 15). The stored parameters and sel parameter are used by the tag to determine whether the query command is sent to itself. The stored parameters include the corresponding session, in which the corresponding state is A or B. The sel parameter is the configuration of the selected command. When the stored parameters and sel parameter are consistent with the stored parameters and sel parameter stored on the tag, it means that the target of the query command includes this tag. Therefore, the tag is in the (0, 2) slot. Q-1 The tag selects a random number (also called a count value) within the range and places it into the time slot counter. When the time slot counter is non-zero (i.e., the count value in the time slot counter is non-zero), the tag enters the arbitration state. When the time slot counter is zero, the tag enters the acknowledgment state and sends the newly generated RN16 to the reader.

[0100] In other words, for tags that meet the set criteria and are selected by the reader using the selection command, a count value is generated. Each tag with a count value of zero sends a response message (carrying RN16) to the reader and transitions to the response state. Conversely, tags that meet other conditions will change certain attributes and flags, thereby leaving the tag group, which helps reduce duplicate identification.

[0101] In some embodiments, if the count value selected by the tag is 0, it directly enters the response state. That is, through... Figure 5 The branch shown in 1a enters the response state.

[0102] In other embodiments, if the tag selects a non-zero count value (e.g., 5), it enters the arbitration state. The reader can send an adjustment query command to the tag, and upon receiving the command, the tag generates a new count value. The reader can also send a repeat query command to the tag. Each time the tag receives a repeat query command, it decrements its time slot counter by one until the counter reaches zero, at which point it enters the response state and sends the latest RN16 to the reader. In other words, the tag can... Figure 5 As shown in 1b, the process first transitions from the ready state to the arbitration state, and then from the arbitration state to the response state.

[0103] In the acknowledgment state, if a valid (or effective) acknowledgment message is received, the tag transitions to the acknowledgment state and sends tag information to the reader, such as, but not limited to, PC, EPC, and CRC-16. Conversely, if the tag fails to receive an acknowledgment message or receives an invalid acknowledgment message, the tag returns to the arbitration state.

[0104] A valid acknowledgment message refers to an acknowledgment message carrying a valid RN16. A valid RN16 is the RN16 carried by the tag in the response message. An invalid acknowledgment message is an acknowledgment message carrying an invalid RN16. The values ​​of an invalid RN16 and a valid RN16 are different.

[0105] When a tag in the acknowledgment state receives a random number request (Req_RN) command, if the command carries a valid RN16 and the access password is non-zero, the tag transitions to the open state and sends a handle back to the reader. Conversely, if the access password is 0, the tag transitions to the secure state and sends a new RN16 back to the reader. The handle can be the newly generated RN16. This RN16 may differ from the value of the RN16 in the response message.

[0106] A tag in the open state can execute access commands except for the lock command. A tag in the open state can transition to any state except the acknowledged state.

[0107] When a tag in the open state receives a valid Access command, if the access password is non-zero, the tag transitions to the secure state, retaining the handle generated when it transitioned from the confirmed state to the open state.

[0108] Normally, a tag in a secure state can execute all access commands, and a tag in a secure state can transition to any state other than open and confirmed states.

[0109] Furthermore, to enhance information security, such as ensuring the protection of private data, tags should also be deactivated. Specifically, when a tag in the open or secure state receives a deactivation command with a valid non-zero killpassword and a valid handle, it will enter the deactivation state. The deactivation operation is irreversible; that is, once a tag is deactivated, it is permanently disabled, meaning the tag will never respond to reader commands again.

[0110] When entering the deactivation state, the tag should notify the reader that the deactivation operation was successful and cease responding to reader commands. Furthermore, the deactivated tag should remain in the deactivated state under all circumstances, such as immediately after power-on.

[0111] It should be noted that, Figure 5 Only some of the transition conditions between states are shown. For the specific transition relationships between states, please refer to the prior art. The embodiments of this application will not be described in detail.

[0112] 5. Interaction sequence between tags and readers

[0113] It should be noted that the interaction between the tag and the reader should generally meet the timing requirements in Table 1 below. In the open state, there is no limit to the maximum delay between the tag response and the reader's transmission.

[0114] Table 1

[0115]

[0116] Figure 6 The interaction timing between the tag and the reader is shown, and this timing is consistent with Table 1. Figure 6 In this process, the reader sends a selection command, which can indicate the selected (SL) identifier (or inventoried) flag and a mask to select a set of tags.

[0117] Next, the reader sends a query, and in response to the query, a tag is generated if the flag (selection flag or inventory flag) and the mask both match (0, 2). Q-1 A random number k between () and ().

[0118] The reader sends a QueryRep, and in response to the QueryRep received from the reader, the tag executes k = k - 1. When the value of k is reduced to 0, the tag sends RN16 to the reader.

[0119] In some situations, RN16 responses from multiple tags may collide, or the reader may not receive an RN16 from the tag. In such cases, the reader can adjust the Q value by sending a QueryAdjust. In response to the QueryAdjust received from the reader, the tag generates a (0, 2) value. Q-1 A random number m between 0 and 1. The reader sends a QueryRep to the tag. In response to the QueryRep, the tag executes m = m - 1. When m is 0, the tag sends RN16 to the reader and enters the Reply state. In some cases, after the reader sends a QueryRep, if it does not detect the tag's RN16 response within a specified period (e.g., the tag's m has not decreased to 0), the reader continues to send QueryRep and waits for the tag's RN16 response.

[0120] In other cases, if the reader does not detect a collision, meaning only one tag responds with RN16 at any given time, the reader sends an acknowledgment message to that tag. Upon receiving a valid acknowledgment message from the reader, the tag sends its tag information back to the reader. If the tag information is valid, the reader has completed its inventory of that tag and can begin inventorying the next tag. Conversely, if the tag information is invalid, the reader sends a non-acknowledgment (NACK) message to the tag that responded with invalid tag information.

[0121] In other cases, after receiving the RN16 from the tag, the reader sends an invalid acknowledgment message (carrying an invalid RN16) to the tag. In this situation, the tag does not send tag information back to the reader, and the reader cannot detect the tag information for a period of time. In this case, the reader continues to send repeated query commands and waits for the tag to send back the RN16.

[0122] 6. Storage space in the tag

[0123] In the above process, the EPC, access password, and other related components are stored in designated storage space on the tag. As one possible implementation, logically, the tag's storage area is divided into four different storage areas, each consisting of one or more storage words. The logical storage mapping table is as follows: Figure 7 As shown, these storage areas are as follows:

[0124] (1) Reserved storage area: Used to store the passwords required for deactivation and access functions. Among them, storage addresses 00h to 1Fh store the deactivation password, and 20h to 3Fh store the access password.

[0125] (2) EPC Storage Area. The storage area from address 00h to 0Fh is used to store CRC-16, the storage area from address 10h to 1Fh is used to store the PC bit, and addresses 20h and above store information used to identify the object to which the tag is attached (such as the EPC). The PC bit can be subdivided: addresses 10h to 14h store the EPC length, addresses 15h to 17h store reserved for future use (RFU) bits, and addresses 18h to 1Fh store the numbering system identifier (NSI). Optionally, CRC-16, PC, and EPC can be stored in a high-order bit-first manner, for example, the high-order bits of the EPC can be stored at address 20h. Of course, other methods can also be used.

[0126] (3) Tag-identification or tag identifier (TID) storage area. Optionally, addresses 00h to 07h store an 8-bit class identification code assigned by ISO / IEC 15693 (EPCglobal code is 11100010_2). Areas above address 07h should contain sufficient identification information to allow the reader to uniquely identify the custom commands and / or optional commands supported by the tag. For tags with class number 11100010_2 assigned by ISO / IEC 15693, this identification information will constitute, for example, a 12-bit tag mask designer identifier and a 12-bit tag model code. The tag mask designer identifier is stored at addresses 08h to 13h, and the model code is stored at addresses 14h to 1Fh. Tags may store tag- and provider-specific data (e.g., tag serial number) in areas of the TID area above address 1Fh.

[0127] (4) User storage area. This area allows storage of user-specific data, and its storage organization structure can be defined by the user.

[0128] 7. Tag positioning method

[0129] In some scenarios, electronic tags can be attached to target objects, and readers can determine the location of the target object by locating the tag. For example, in logistics and transportation, it may be necessary to know the specific location of different goods, and this can be achieved by the interaction between readers and tags.

[0130] In RFID, commonly used positioning methods include time of arrival (TOA), time difference of arrival (TDOA), angle of arrival (AoA), and received signal strength indication (RSSI). Positioning can be achieved using any of these methods, or a combination of methods.

[0131] In TOA-based positioning methods, the propagation time of the signal needs to be measured. Therefore, the timing of the transmitting and receiving devices in the positioning system must be precisely synchronized; otherwise, it can easily lead to significant errors. For example, if there is a small error in the measurement of the propagation time, the error will be magnified many times after multiplying the propagation time by the speed of light. It can be seen that when it is difficult to ensure synchronization between transmission and reception, this method cannot guarantee positioning accuracy. In addition, in multipath environments, the channel conditions of different paths are often different, which will also affect the positioning accuracy.

[0132] The positioning method based on TDOA is similar in principle to the positioning method based on ToA. It can be seen that both TOA and TDOA-based positioning methods have high requirements for system clock synchronization, therefore, these two positioning methods are relatively expensive.

[0133] In AoA-based positioning methods, it is necessary to measure the angle between the tag and the reader antenna. This requires the tag and reader antenna to maintain a line-of-sight distance. If this requirement cannot be met, due to multipath effects, shadowing effects, and antenna orientation, the signal will arrive at the reader antenna from different directions, making it impossible for the antenna to make a normal judgment. This reduces the accuracy of AoA-based positioning methods to some extent. Therefore, AoA-based positioning methods require the receiving antenna to have a strong angle resolution capability; even a small angular error will reduce positioning accuracy.

[0134] RSSI-based positioning methods are applicable to tags with embedded chips. In RSSI-based positioning, the tag sends a signal, which experiences signal loss after propagating a certain distance. The farther the signal travels, the greater the loss, and the weaker the signal strength received at the receiver. Based on this principle, when the signal reaches the reader, the reader can infer the distance to the tag based on the RSSI (Received Signal Strength Indicator) of the arriving signal. Specifically, the higher the RSSI, the farther the distance between the tag and the reader is generally.

[0135] However, the complexity of the wireless environment and other factors affect the relationship between distance and signal strength. Path loss may vary in different environments. Therefore, when the distance between the tag and the reader is constant, the RSSI measured by the reader may differ in different wireless environments, leading to inaccurate distance measurements. It is evident that in RSSI positioning methods, the reader needs to know not only the RSSI but also the signal transmission loss model in the actual environment to calculate the tag's specific location. In other words, this positioning method requires testing in different environments to obtain the loss model under different conditions. In one implementation, multiple reference points can be deployed. The reader measures the RSSI of the transmitted signals at these reference points. The reference point whose RSSI is closest to the tag's RSSI is considered the tag's location. This scheme has high implementation complexity, affecting the efficiency of tag positioning.

[0136] Currently, tags without chips can be located via reflection. The reader sends a positioning signal, and the tag, upon receiving this signal, modulates it to obtain a modulated signal, which it then sends (reflects) back to the reader. It's important to note that other objects can also reflect the positioning signal and send a reflected signal back to the reader. The reader needs to detect the modulated signal from the tag amidst ambient noise to pinpoint its location.

[0137] In this embodiment, the positioning signal can be of various types. The tag's signal modulation method can also be various. For example, the positioning signal is an ultra-wideband (UWB) signal. The reader's received signal is as follows: Figure 8 As shown, the reflected signal (i.e., the modulated signal) from the tag has different characteristics from the reflected signal (i.e., noise) from other objects. Therefore, the reader can detect the modulated signal from the tag from the noise.

[0138] For example, the positioning signal can be a chirp signal. Correspondingly, the tag uses a specular reflection frequency modulation method on the chirp signal from the reader, inverting the chirp signal frequency to distinguish between ambient reflection and tag reflection. Scenarios using chirp signals as positioning signals include... Figure 9 As shown. Among them, Figure 9 (a) shows the time-domain and frequency-domain characteristics of the chirp signal. Figure 9 (b) shows the time-domain and frequency-domain characteristics of the modulated signal obtained by modulating the chirp signal with the tag. Figure 9 (c) shows the time-domain and frequency-domain characteristics of the chirp signal reflected by other objects.

[0139] For example, if the tag is a surface acoustic wave (SAW) tag, the tag can also use time-position coding or pulse position modulation (PPM) for signal modulation. The modulation process is as follows: Figure 10 As shown.

[0140] For tags without chips, in scenarios with a large number of such tags, if the reader sends a positioning signal, multiple tags within the reader's coverage area may simultaneously reflect the modulated signal, causing signal conflicts between tags. On the one hand, the signals may overlap and interfere with each other, affecting positioning accuracy. On the other hand, in order to reduce signal conflicts, the reader needs to run a conflict resolution mechanism, resulting in low positioning efficiency.

[0141] Therefore, embodiments of this application provide a tag positioning method, which is applied to RFID systems or similar systems requiring tag positioning. Taking its application in an RFID system as an example, such as... Figure 11 The diagram illustrates the architecture of a possible RFID system according to an embodiment of this application. The RFID system includes electronic tags (which may be simply referred to as tags) and readers (also known as card readers, etc.).

[0142] In this design, the card reader integrates an antenna used for transmitting and receiving information. Alternatively, the card reader and antenna can be separate. Communication between the tag and the card reader can be achieved via a wireless connection.

[0143] For detailed information on card readers and tags, please refer to the above text; it will not be repeated here.

[0144] Optionally, the RFID system also includes a backend system. The backend system includes a computer. The computer is used to interact with the card reader, for example, to obtain information from the card reader. The computer is also used to process the information obtained from the card reader.

[0145] Optionally, the reader and the backend system computer can be connected via a wireless local area network (WLAN) or an Ethernet serial port. The WLAN can be a network conforming to standards such as 802.11b or 802.11g.

[0146] It should be noted that the system to which the embodiments of this application apply may also include Figure 11 Other equipment besides these. Figure 11 This is merely a schematic diagram of a system architecture applicable to an embodiment of this application. Of course, embodiments of this application can also be applied to other systems, and this embodiment does not specifically limit them.

[0147] The technical solutions of the embodiments of this application will now be described with reference to the accompanying drawings. In the description of this application, unless otherwise stated, "multiple" refers to two or more. Furthermore, to facilitate a clear description of the technical solutions of the embodiments of this application, the terms "first," "second," etc., are used in the embodiments of this application to distinguish identical or similar items with substantially the same function and effect. Those skilled in the art will understand that the terms "first," "second," etc., do not limit the quantity or execution order, and that "first," "second," etc., do not necessarily imply differences.

[0148] Furthermore, the network architecture and business scenarios described in the embodiments of this application are for the purpose of more clearly illustrating the technical solutions of the embodiments of this application, and do not constitute a limitation on the technical solutions provided in the embodiments of this application. As those skilled in the art will know, with the evolution of network architecture and the emergence of new business scenarios, the technical solutions provided in the embodiments of this application are also applicable to similar technical problems.

[0149] Optionally, the label in the embodiments of this application may have Figure 12 The structure shown.

[0150] The receiving antenna is used to receive signals from readers, such as positioning signals and indication signals (i.e., the first signal) from readers.

[0151] The envelope detection module is used to perform envelope detection on high-frequency positioning signals, transferring the positioning signals from the high-frequency band back to the baseband.

[0152] The pulse-interval encoding (PIE) module is used to perform PIE decoding on the envelope detection results.

[0153] The baseband processing unit (BPU) is used for baseband processing.

[0154] The biphase spatial coding (FM0) module is used to encode information received from the baseband.

[0155] The modulation module is used to modulate the FM0-encoded information to shift the baseband signal to a higher frequency. One possible implementation is to use a carrier wave from the reader as the modulation carrier.

[0156] The modulation module can be implemented by a modulation circuit. Optionally, the modulation circuit can be a programmable logic circuit.

[0157] The transmitting antenna is used to reflect modulated signals, positioning sequences (i.e., the first sequence) to the reader.

[0158] An energy storage module is used for energy storage. As one possible implementation, the energy stored in this module can originate from a carrier wave received from the reader. This energy can then be used for tag-reader interaction.

[0159] In some embodiments, the transmitting and receiving antennas can be integrated together, meaning that one antenna can be used for both transmitting and receiving. Alternatively, one antenna can be used only for either transmitting or receiving.

[0160] Figure 12 The structure shown is merely an exemplary example of a label; actual labels may include even more advanced features. Figure 12 The modules shown may include more or fewer modules, or may be split into parts or combined. The embodiments in this application do not limit the specific implementation of the labels.

[0161] The following will combine Figures 1 to 12 The tag positioning method provided in the embodiments of this application will be described in detail.

[0162] In this embodiment, the existing tag state machine is improved by adding a positioning state. The positioning state is used to locate the electronic tag. The state transition conditions between this newly added positioning state and other state machines are as follows: Figure 13 As shown. Figure 13 The partial transition conditions between partial states are shown only as an example.

[0163] like Figure 14 As shown, the tag positioning method provided in this application includes the following steps:

[0164] S101, The reader sends an instruction signal to the electronic tag.

[0165] Correspondingly, the electronic tag receives the instruction signal (i.e., the first signal) from the reader.

[0166] This instruction signal is used to instruct, control, or request the electronic tag to enter the positioning state.

[0167] Optionally, if the reader sends the indication signaling via broadcast, the indication signaling can be a query positioning command. If the reader sends the indication signaling via unicast, the indication signaling can be a positioning request. If the reader sends the indication signaling via multicast, the indication signaling can be a multicast positioning request (Positioning_Request MultiCast). Alternatively, other forms of signaling may also be used; this application embodiment does not limit the specific form of the indication signaling.

[0168] Optionally, the instruction signaling can be used to configure the slot count parameter (i.e., the first parameter) R to the tag. R is used to instruct the tag to select a random number. For example, a query location command can be used to configure the slot count parameter R to the tag. Alternatively, the slot count parameter R can also be carried in other messages, such as in a selection command or a query command (i.e., the second signaling).

[0169] Optionally, the indication signaling includes a position flag; a true position flag indicates that the tag has entered the position state. Alternatively, the position flag can also be carried in other messages.

[0170] S102. In response to the instruction signal, the electronic tag enters the positioning state.

[0171] It should be noted that the electronic tag can be in any state before entering the positioning state, such as a ready state, a confirmed state, an open state, or a secure state. This application embodiment does not limit the state of the electronic tag before entering the positioning state.

[0172] Optionally, the electronic tag can immediately enter the positioning state after receiving the instruction signal, that is, it can enter the positioning state without delaying for a period of time. Alternatively, the electronic tag can delay for a period of time (i.e., the first time delay) after receiving the instruction signal before entering the positioning state.

[0173] Optionally, the reader sends configuration information (which can also have other names) to the tag. This configuration information includes a delayed entry into positioning state indicator. The delayed entry into positioning state indicator is used to indicate whether the tag delays entering the positioning state for a certain period after receiving the indication signal. As one possible implementation, the delayed entry into positioning state indicator can be 1 bit. When the bit value is 0, it indicates that the tag delays entering the positioning state for a certain period after receiving the indication signal; when the bit value is 1, it indicates that the tag does not delay entering the positioning state after receiving the indication signal, meaning the tag can enter the positioning state immediately after receiving the indication signal.

[0174] Optionally, the delayed entry into the positioning state indication can also be carried in other messages, such as the indication signaling used in this document to indicate entry into the positioning state.

[0175] Optionally, the start time for the tag to enter the positioning state can be pre-configured in the tag. For example, before the reader sends an indication signal to the tag, the reader sends configuration information to the tag, which carries the start time for the tag to enter the positioning state. This start time can be included in the same configuration information as the aforementioned delayed entry into the positioning state indication, or it can be included in different configuration information. In this way, after receiving the indication signal from the reader, the tag can enter the positioning state after the pre-configured start time (e.g., 4 time slots). This method can also be called tag timed arrival to enter the positioning state, that is, after receiving the indication signal from the reader, the tag starts a timer and enters the positioning state after a set time (e.g., after 4 time slots).

[0176] Alternatively, the start time for the tag to enter the positioning state can be dynamically indicated by the reader. For example, the reader sends an indication signaling message to the tag, which includes a slot counter parameter R (or the slot counter parameter R can be carried in other messages). After sending the indication signaling message, the reader sends a counting command to trigger the tag's slot counter to decrement by one. Accordingly, when the tag receives the indication command from the reader and parses the slot counter parameter R carried in the query command, the tag is in the (0, 2) position. R-1 A random number is selected from the range () as the count value, and this count value is placed into the time slot counter. This count value is the initial value of the time slot counter. Alternatively, the tag can automatically time itself according to the time slot counting parameter R, and decrement the time slot counter by one when the timer expires. For example, the tag decrements the time slot counter by one every time slot. The time slot can be configured for the tag by the reader / writer.

[0177] As one possible implementation, the time slot counting parameter R and the time slot counting parameter Q can be different or the same. The time slot counter corresponding to R is different from the time slot counter corresponding to Q. Alternatively, the time slot counter corresponding to R and the time slot counter corresponding to Q can be the same time slot counter.

[0178] In one example, if the tag selects a count value of 0, then the initial value of the slot counter is zero, and in this case, the tag enters the positioning state.

[0179] In another example, if the tag selects a non-zero count value, then the initial value of the time slot counter is not zero. The tag can wait for a counting command from the reader and decrement the time slot counter by one each time a counting command is received, until the time slot counter is zero, at which point the tag enters the positioning state.

[0180] S103. In the positioning state, the electronic tag performs a positioning operation.

[0181] In the positioning state, the tag's positioning operation can be a reflection operation or a sequence transmission operation. Optionally, the reader can send configuration information to the tag to indicate whether the tag's positioning operation is a reflection operation or a sequence transmission operation.

[0182] The following sections will introduce two positioning operations: reflection and sequence sending.

[0183] 1. Reflection operation: After the tag enters the positioning state, it modulates the signal received from the reader and reflects the modulated signal back to the reader. The reader locates the tag based on the modulated signal reflected by the tag.

[0184] The tag modulates the received signal to distinguish it from other signals. The positioning signal can be a continuous wave or a wideband pulse waveform. In some scenarios, modulation information needs to be added to the positioning signal from the reader. For continuous waves, modulation information can be added using linear frequency modulation (FM), specifically triangular wave, sawtooth wave, coded modulation, or noise FM, etc. FM can be single-tone FM, 15kHz velocity FM, 180kHz FM, or sequence FM. For pulse waveforms, modulation information can be added using coded modulation, step-frequency waves, etc. Coded modulation can use binary codes with good autocorrelation and cross-correlation, such as m-codes, or CAZAC sequences with good correlation.

[0185] As one possible implementation, a circuit for signal modulation can be set in the tag. When the tag enters the positioning state, the tag can switch to this circuit to achieve signal modulation.

[0186] Alternatively, as another possible implementation, before the tag enters the positioning state, the reader configures the programmable logic circuitry in the tag and sends the configuration information to the tag. After the tag enters the positioning state, signal modulation can be achieved through the programmable logic circuitry according to the configuration information.

[0187] The configuration information of the programmable logic circuit may include: the connection method of the logic gates, or the index of the pre-designed connection method, or the connection pattern of the logic gates.

[0188] Compared to signal modulation via switching to a fixed circuit, signal modulation using programmable logic circuits (PLCs) is more flexible. The reader can configure different PLC information (such as gate connection methods) for tags based on its own strategy. It's important to note that once a reader configures PLC information for a tag, this information should remain unchanged while the tag is in the positioning state. When the tag exits the positioning state, the PLC information can be updated (e.g., a new gate connection method), and signal modulation can be achieved using the new gate connection method the next time the tag enters the positioning state.

[0189] Optionally, the reader can also configure and send signal modulation-related information to the tag. This information may include, for example, the modulation method. The modulation method includes, but is not limited to, code division modulation (CDM) or frequency modulation (FM). If the modulation method is CDM, the signal modulation-related information may also include modulation symbols. If the modulation method is FM, the signal modulation-related information may also include frequency hopping patterns. Thus, after entering the positioning state, the tag can modulate the signal from the reader according to the corresponding modulation method based on the signal modulation-related configuration information and reflect the modulated signal back to the reader.

[0190] Tag localization methods based on reflection operations can stagger the timing of tags entering the localization state, as the timing is controlled by the reader. This reduces the probability of collisions between the transmitted signals of different tags. Therefore, this method can be applied to large-scale tag scenarios, achieving collision-free tag localization within an effective range. Furthermore, reduced collisions between tag signals allow the reader to decrease resource consumption for collision resolution, enabling more resources to be allocated to tag localization and thus improving localization efficiency.

[0191] 2. Sequence sending operation: After the tag enters the positioning state, it sends a specific sequence to the reader so that the reader can locate the tag based on the specific sequence. Sequence sending operation can be applied in RSSI positioning scenarios or other similar positioning scenarios.

[0192] As one possible implementation, the reader configures sequences at the group level; that is, the reader configures a set of sequences for its stored tag groups, and a set of sequences includes one or more sequences. Each tag determines the sequence it uses. In some embodiments, multiple sets of sequences are pre-stored within the tag, and the reader sends the index of the sequence group to the tags in the group to indicate the set of sequences that the tags in that group need to select. In other embodiments, the reader may also send the sequence group directly to the tags in that group. This application does not limit the specific implementation method of the reader configuring sequence groups for tag groups.

[0193] As another possible implementation, the reader configures sequences at the individual tag level, meaning the reader configures separate sequences for different tags. Optionally, the reader can directly send the sequence to the tag, send the index corresponding to the sequence, or send parameters associated with the sequence. In the case where the reader sends parameters associated with the sequence to the tag, the tag can determine the required sequence based on the relationship between the parameter and the sequence.

[0194] Alternatively, the reader sends parameters to the tag to generate the sequence, and the tag generates the sequence based on those parameters.

[0195] Alternatively, the sequence can be pre-configured in the tag. For example, it can be configured in the tag at the factory.

[0196] Different tags can have different sequences, allowing the reader to distinguish between different tags based on the received sequences. Thus, when receiving a sequence from a tag, the reader can not only detect the strength of the signal used to transmit that sequence, but also, because different tags have different sequences, the reader can blindly detect the tag's identification.

[0197] Furthermore, the positioning sequence (i.e., the first sequence) can be a sequence with good correlation. Optionally, the positioning sequence can be, but is not limited to, Gold sequences, Gray code, CAZAC sequences, etc., or other sequences with good correlation.

[0198] In this embodiment, since both the reader and the tag are aware of the location sequence sent by the tag, the reader can not only obtain signal strength by measuring the location sequence, but also estimate the channel and obtain more channel information, such as phase information and loss models, to assist in calculating the location distance. In this case, the number of reference points deployed can be reduced or eliminated.

[0199] Furthermore, the tag can send location sequences multiple times, and the reader can merge and filter multiple location sequences from the tag to improve measurement accuracy.

[0200] Furthermore, once the tag is in the location state, it can actively send location sequences multiple times. This means the tag can send location sequences without being triggered by reader commands. This reduces the reader's signaling overhead and improves tag location efficiency.

[0201] In this embodiment, after the tag enters the positioning state, it can switch to a certain circuit to send the positioning sequence, or send the positioning sequence through a programmable logic circuit. This embodiment does not limit the specific implementation method for sending the positioning sequence.

[0202] In this embodiment, some configuration information (such as the first parameter in the configuration information) can be carried in the fourth signaling. The fourth signaling can be the first signaling, the second signaling, or other signaling. For example, the first parameter can be carried in broadcast messages in the inventory process, such as configuration information carried in Select, Query, or other commands. Optionally, the first parameter can be a tag-level dedicated parameter. The first parameter includes, but is not limited to, the configuration information of the programmable logic circuit mentioned above, the configuration information related to signal modulation, and the configuration information of the sequence. For example, when the tag positioning operation is a reflection operation, the configuration information is the signal modulation method, frequency hopping pattern, and logic gate connection pattern. When the tag positioning operation is a sequence transmission, the configuration information can be, for example, the sequence index and the specific sequence.

[0203] Optionally, the dedicated parameters include parameters available to the tag during the first time period (which may be referred to as long-term parameters) or short-term parameters. The first time period can be carried in the configuration information. If the first time period is set to be relatively long, the reader does not need to frequently update the dedicated parameters of the tag, so as to save signaling. Parameters other than long-term parameters in the first parameters may be referred to as short-term parameters.

[0204] In other embodiments, some configuration information (such as the second parameter in the configuration information) can be carried in the fifth signaling. Optionally, the second parameter can be a common parameter at the reader level. Tags within the coverage area of ​​the reader can use the second parameter. The fifth signaling can be the first signaling, the second signaling, or other signaling. For example, the second parameter can be carried in a unicast message sent by the reader. In this way, the reader can send configuration information to a specified tag through a unicast message. For example, the unicast message can be an ACK message used to respond to RN16, or it can be a dedicated signaling message from the reader for the tag after the tag enters a safe state or an open state. In this approach, the reader does not need to configure dedicated parameters for each tag, which can reduce signaling overhead.

[0205] The fourth signaling and the fifth signaling may be the same signaling or different signaling. That is to say, configuration information can be transmitted through one signaling or through multiple signaling (such as the fourth signaling and the fifth signaling).

[0206] For example, the reader configures a sequence group for the tag. This sequence group can be tag-specific (i.e., a long-term parameter), meaning different tags have different sequence groups. This sequence group can be effective for the tag in the next 1000 inventory runs. During each inventory run, the reader can also configure a sequence index for the tag (to indicate which sequence in the sequence group to use). The sequence index configured in each inventory run can be different, meaning the sequence index is a short-term parameter.

[0207] In other embodiments, the common parameter (i.e., the second parameter) can also be a long-term parameter or a short-term parameter. For example, the reader broadcasts a sequence group, which is a second parameter that can be used by a group of tags within the reader's radio frequency range. This sequence group can be effective for the group of tags in the future, for example, 1000 inventory cycles. During each inventory cycle, the reader can also configure different sequence indices for different tags.

[0208] S104, The tag exits the positioning state.

[0209] The tag exits the positioning state, also known as the tag jumps out of the positioning state.

[0210] Optionally, the triggering condition for the tag to exit the positioning state can be: the reader triggers the tag to exit the positioning state through a command, or the tag exits the positioning state when the scheduled time arrives.

[0211] Optionally, the tag determines the timing for exiting the positioning state. Specifically, the reader sends configuration information to the tag, which carries the timing duration. This timing duration can be included in the same configuration information or in different configuration information. Thus, after entering the positioning state, the tag can start a timer, and the timer's duration is the duration indicated by the configuration information. When the timer expires, the tag can exit the positioning state. For example, after entering the positioning state, the tag may exit the positioning state after a delay of four time slots (the second delay).

[0212] Alternatively, the tag may exit the location state if a first condition is met. This first condition could be that the number of transmitted location sequences or modulated signals reaches a threshold. For example, the tag exits the location state after transmitting L modulated signals. Or, the tag exits the location state after transmitting M location sequences. L and M are both positive integers, and L and M can be configured by the reader for the tag, or by other configuration methods.

[0213] Optionally, the reader can trigger the tag to exit the positioning state via commands. Specifically, the reader can trigger the tag to exit the positioning state through one or more commands. For example, the reader can send a command to the tag to indicate, control, or request the tag to exit the positioning state; upon receiving the command, the tag can exit the positioning state. Another example is that the reader can send a counting command to the tag; each time the tag receives a counting command, its time slot counter increments by 1 until the time slot counter reaches the configured count value, at which point the tag exits the positioning state. Yet another example is that the reader can send a command to the tag to trigger a self-timer that exits the positioning state upon reaching the set time; upon receiving this command, the tag can delay the timer duration (e.g., 4 time slots) before exiting the positioning state.

[0214] Alternatively, the reader can, after receiving a preset number of positioning sequences or modulation signals from the tag, instruct the tag to exit the positioning state. This means that when a preset number of positioning sequences or modulation signals are sufficient to achieve high-precision tag positioning, the tag can be instructed to exit the positioning state. This reduces the power consumption or resource consumption caused by the tag sending positioning sequences or modulation signals multiple times. For example, the reader may instruct the tag to exit the positioning state after receiving N positioning sequences from the tag. Or, for another example, the reader may instruct the tag to exit the positioning state after receiving P modulation signals from the tag. N and P are both positive integers, and N and P can be configured by the reader for the tag, or other configuration methods.

[0215] In some embodiments, the state of the tag after exiting the positioning state can be a specified state. Optionally, this specified state is pre-configured in the tag; for example, the reader pre-configures the state of the tag after exiting the positioning state, or it can be other pre-configuration methods. Alternatively, the reader can dynamically indicate the specified state to the tag via a command.

[0216] In other embodiments, the tag can transition from the positioning state to a state prior to entering the positioning state. This application does not limit the state of the tag after exiting the positioning state, nor how to set the state after exiting the positioning state.

[0217] In some embodiments, tags in a positioning state can reduce signaling processing, for example, only processing high-priority signaling such as select, kill, and query.

[0218] The tag positioning method provided in this application adds a positioning state to the tag's state machine. The tag can enter the positioning state under the control of the reader / writer and perform positioning operations within it. Compared to the current timing method for tags without chips, in this application embodiment, since the timing of the tag entering the positioning state is controlled by the reader / writer, the entry times of different tags can typically be staggered, reducing the probability of collisions between the tag's transmission signals and those of other tags. Furthermore, with reduced collisions between tag transmission signals, the reader / writer can reduce resource consumption for collision resolution, allowing more resources to be used for tag positioning and improving positioning efficiency. Compared to the current positioning method for tags with chips, after entering the positioning state, the tag can actively perform positioning operations without being triggered by a corresponding reader / writer command each time, reducing the reader's signaling overhead and thus improving positioning efficiency.

[0219] In other embodiments, after the tag enters the positioning state, the probability of the reader detecting the tag's modulation signal under constant false alarm rate (CFAR) conditions can be increased (i.e., the probability of detecting the modulation signal from noise) through multi-pulse (or pulse accumulation) methods. In the embodiments of this application, distance resolution can be improved through multi-pulse methods.

[0220] Multipulse is a concept relative to single pulse. Single pulse means that the tag reflects a modulated signal once, and the reader locates the tag based on that single modulated signal. Multipulse means that the tag reflects the modulated signal multiple times, and the reader performs coherent or incoherent merging processing on the multiple modulated signals to obtain a merged signal, and locates the tag based on the merged signal (i.e., the result of the merging process).

[0221] The following describes the derivation and calculation process for improving range resolution under multi-pulse conditions.

[0222] First, the relationship between the distance between the reader and the tag and the signal-to-noise ratio (SNR) is introduced. As one possible implementation, the relationship between SNR and distance can be represented by the following formula:

[0223]

[0224] Where Pt is the transmit power of the reader, G is the antenna gain of the reader, λ is the wavelength of the transmitted signal, k is the Boltzmann constant, T0 is the Kelvin temperature, B is the noise bandwidth, R is the distance between the reader and the tag, L is the loss factor, i.e., the scene-related loss, and F is the noise figure performance index, which is device-related.

[0225] From Formula 1, it can be deduced that the ratio between any two SNRs is inversely proportional to the fourth power of the corresponding distance ratio. That is, the following relationship holds:

[0226]

[0227] Formula 2 can also be expressed as Formula 3:

[0228]

[0229] It can be seen that, with a fixed reader transmission power, the greater the distance between the tag and the reader, the weaker the signal received by the tag from the reader, and the lower the SNR.

[0230] The following sections present the detection probabilities of detecting modulated signals using a single-pulse method and a multi-pulse method. First, the detection probability P of detecting modulated signals using the single-pulse method is given. D The formula:

[0231]

[0232]

[0233] Q is the Marcum Q function, as mentioned above. A represents the amplitude of the modulating signal, Ψ 2 This represents the noise power, where r is the sample of the signal received by the reader, and r exceeds the detection threshold V. T The probability of detection is P. fa It represents the false alarm probability, I0 being the zeroth-order modified Bessel function of the first kind. In some examples, V... T It can be a voltage value. The false alarm probability, i.e., when the signal received by the receiver (here referring to the reader / writer) contains only noise, the received signal sample r exceeds the detection threshold V. T The probability of.

[0234] The above calculation process can be simplified to the following expression:

[0235]

[0236]

[0237]

[0238] d n+1 =d n d1

[0239]

[0240]

[0241] Next, the detection probability of the modulated signal is given by the multi-pulse method (i.e., the tag reflects multiple times, the reader combines multiple modulated signals, and locates the tag based on the combined signal). In the pulse number n... p If the value is greater than 1, i.e., in the case of multiple pulses, the detection probability can be calculated using the Gram-Charlier series. The detection probability for multiple pulses can then be expressed as:

[0242]

[0243] Where the constants C3, C4, and C6 are sparse in the Gram-Charlier series, and V can be expressed as follows:

[0244]

[0245] Among them, V T Indicates the detection threshold.

[0246] It should be noted that the values ​​of C3, C4, C6, and w can vary depending on the target undulation type. The target undulation type is related to the target's shape, size, etc. Typically, an undulation model can be built for the target to estimate its shape and size. Currently available undulation models include Swerling I, II, III, IV, Swerling 0, Swerling V, etc.

[0247] In this case, target undulations can be disregarded, i.e., the target's cross-sectional area is assumed to be constant. This undulation model is called Swerling 0 or Swerling V. In this case, the values ​​of the above parameters can be:

[0248]

[0249]

[0250]

[0251]

[0252] As can be seen from the above formula, the detection probability is related to the SNR, and the SNR is related to the distance. This means that the detection probability is related to the distance. Generally, with the same detection probability, the SNR of a single pulse is higher than that of a multi-pulse pulse. In other words, by using a multi-pulse method, the reader can detect the modulated signal even with a low SNR, which means that the reader can detect the modulated signal even when the tag is at a greater distance. For an example of noisy incoherent combining, see [link to example]. Figure 15 The vertical axis represents the detection probability, the horizontal axis represents the SNR, and np represents the pulse count. When the false alarm probability is constant at 10... -9 When the detection probability is 0.8, the SNR of the 10-pulse cumulative method is 8.55 dB lower than that of the single-pulse method. Furthermore, based on the relationship between SNR and positioning distance, it can be seen that the 10-pulse method can increase the positioning distance by 1.64 times compared to the single-pulse method.

[0253] The following describes in detail the tag positioning method provided in the embodiments of this application, with specific scenarios as examples.

[0254] Example 1

[0255] In Embodiment 1, the reader sends an indication signal to the tag via broadcast. After receiving the indication signal, the tag delays for a period of time (i.e., the first delay) before entering the positioning state. The reader then sends a command to the tag to trigger it to exit the positioning state. See also... Figure 16 The method includes:

[0256] S1a, Reader broadcast configuration information.

[0257] in, Figure 16 The following example illustrates how configuration information can be carried in a selection command. It's understood that configuration information can also be carried in other messages. Configuration information includes, but is not limited to, one or more of the following: the time of entering the positioning state, the duration the tag remains in the positioning state, signal modulation-related information, programmable logic circuit information, and a delayed entry into the positioning state indication.

[0258] also, Figure 16 In this example, the tag is in a ready state before entering the positioning state. However, the tag can be in other states before entering the positioning state, and this application does not limit this.

[0259] also, Figure 16 In this example, we will use the first electronic note and the second electronic tag as examples. In fact, the reader can interact with more electronic tags in a similar way.

[0260] S2a, Reader broadcasts a query and location command.

[0261] This query positioning command is the same as the instruction signaling mentioned above used to instruct the tag to enter the positioning state. It can be understood that when there is a need to locate a tag, the reader can broadcast a query positioning command to instruct the tag to enter the positioning state, thereby enabling the positioning of the tag in the positioning state.

[0262] Optionally, the query location command can carry the slot count parameter R.

[0263] S3a, the first electronic tag moves from the ready state to the positioning state.

[0264] When the first electronic tag receives a query location command from the reader, it can parse the time slot count parameter R carried in the query location command, select a count value, and put the count value into the time slot counter. Figure 16 Taking the first electronic tag with a count value of zero as an example, when the count value is zero and the time slot counter is also zero, the first electronic tag enters the positioning state.

[0265] Of course, the count value selected for the first electronic tag can also be other values, and correspondingly, the timing of the first electronic tag entering the positioning state can change depending on the count value.

[0266] S4a, Reader broadcasts the Query Positioning Rep command.

[0267] As one possible implementation, the repeated query location command can be the counting command mentioned above. Each repeated query location command is used to trigger the tag's slot counter to decrement by one.

[0268] S5a, Reader broadcast signal.

[0269] It should be noted that the reader broadcasts a signal so that tags within its radio frequency range can receive the broadcast signal, modulate the broadcast signal, and reflect the modulated signal.

[0270] (Optional step) S6a: The first electronic tag in the positioning state modulates the signal from the reader.

[0271] As one possible implementation, after the first electronic tag enters the positioning state, it begins to modulate the signal from the reader.

[0272] Optionally, after entering the positioning state, the first electronic tag can switch to the corresponding modulation circuit to complete signal modulation. Alternatively, after entering the positioning state, the first electronic tag can perform signal modulation through the programmable logic circuit according to the pre-configured programmable logic circuit information (such as the pre-configured logic gate connection method).

[0273] In some embodiments, to distinguish between the location signal reflected by the tag and noise, the tag can modulate the location signal, that is, add modulation information to the location signal, such as performing frequency domain transformation (e.g., frequency flipping) on ​​the location signal. Accordingly, the modulated signal sent by the tag to the reader is a signal with the added modulation information.

[0274] In other embodiments, the step of modulating the positioning signal mentioned herein may also be an optional step. For example, in some cases, there are interference cancellation methods sufficient to distinguish the positioning signal reflected by the tag from noise, so the tag does not need to modulate the positioning signal, thereby reducing the implementation complexity of the tag. Accordingly, the modulated signal sent by the tag to the reader can be replaced with a signal without modulation information, that is, the positioning signal is directly reflected.

[0275] It should be noted that tags typically do not encode or perform similar processing on the positioning signals.

[0276] S7a, The first electronic tag reflects the modulated signal to the reader.

[0277] In this embodiment of the application, the first electronic device reflects the modulation signal to the reader, which can also be referred to as the modulation signal reflected to the reader.

[0278] S8a, Reader broadcasts repeated query location command.

[0279] S9a, the second electronic tag moves from the ready state to the positioning state.

[0280] As mentioned above, the reader can trigger the time slot counter of the electronic tag by repeatedly querying the location command. That is, each time the electronic tag receives a repeated query location command, it will decrement the time slot counter by one. When the time slot counter of the second electronic tag decrements to zero, the second electronic tag enters the location state.

[0281] S10a, Reader broadcast signal.

[0282] Optionally, the reader can broadcast signals periodically. Of course, the reader can also broadcast signals in other non-periodic ways according to a strategy.

[0283] S11a, the second electronic tag modulates the signal from the reader to obtain a modulated signal.

[0284] The signal modulation method of the second electronic tag can be found in the signal modulation method of the first electronic tag described above.

[0285] S12a, the second electronic tag reflects the modulated signal to the reader.

[0286] S13a, Reader broadcasts a positioning exit command.

[0287] The positioning exit command is used to instruct the tag to exit positioning mode. For example, the positioning exit command can be the Select Normal command or other commands.

[0288] S14a, In response to the selection command, the first electronic tag and the second electronic tag exit the positioning state.

[0289] It should also be noted that multiple actions under the same step number do not necessarily have to be executed simultaneously. For example, in step 14a, the timing when the first electronic tag exits the positioning state and the timing when the second electronic tag exits the positioning state may be different or the same.

[0290] Example 2

[0291] Unlike Example 1, where the tag exits the positioning state triggered by receiving a command from the reader instructing it to exit the positioning state, in Example 2, the tag exits the positioning state triggered by a timed arrival of the tag. See also... Figure 17 The method includes:

[0292] S1b, Reader broadcast selection command.

[0293] The selection command includes configuration information. This configuration information includes a delay-entry positioning state indicator (e.g., 1 bit, bit value 0) and a start time (e.g., 4 time slots).

[0294] The configuration information also includes the timing duration. The timing duration is the time between when the tag enters the positioning state and when it exits the positioning state. For example, if the tag enters the positioning state at time t1 and the timing duration is t2, then the tag exits the positioning state at time t1 + t2.

[0295] Optionally, the selection command may also include other configuration information.

[0296] S2b, Reader broadcasts a query and location command.

[0297] S3b, the first electronic tag transitions from the ready state to the positioning state.

[0298] S4b, the reader sends a repeat query location command.

[0299] S5b, the second electronic tag transitions from the ready state to the positioning state.

[0300] S6b, Reader broadcast signal.

[0301] S7b, the first electronic tag in the positioning state modulates the signal from the reader, and the second electronic tag in the positioning state modulates the signal from the reader.

[0302] S8b, the first electronic tag reflects the modulation signal to the reader, and the second electronic tag reflects the modulation signal to the reader.

[0303] The specific implementation of steps S1b-S8b can be found in steps S1a-S12a above.

[0304] S9b. At the scheduled arrival time, the first electronic tag and the second electronic tag exit the positioning state (i.e., jump out of the positioning state).

[0305] For example, if the pre-configured timing duration is 20 time slots, then the first electronic tag will exit the positioning state after a 20-time-slot delay, starting from the moment it enters the positioning state. The second electronic tag will exit the positioning state according to a similar mechanism.

[0306] Example 3

[0307] Unlike in Embodiment 1, where the reader and writer repeatedly query the positioning command to time the tag and trigger the tag to enter the positioning state when the timer arrives, in Embodiment 3, the tag can automatically time itself based on the time slot count parameter R in the query positioning command (for example, every time slot (i.e., a preset time), the time slot counter is decremented by one (or a random number is decremented by one)), and enter the positioning state when the timer arrives.

[0308] See Figure 18 The method includes:

[0309] S1c, S2c. Steps S1c and S2c can be found in S1a and S2a above.

[0310] The method also includes: S3c, the first electronic tag enters the positioning state from the ready state.

[0311] After receiving the query location command from the reader, the first electronic tag can parse the time slot count parameter R carried in the query location command, and then... R-1 A random number is selected within the range and placed into the time slot counter. The first electronic tag can operate the time slot counter according to its own clock. Specifically, the time slot counter is decremented by one every time slot until the time slot counter is zero, at which point the tag enters the positioning state.

[0312] Compared to the embodiment where the reader triggers the tag's slot counter operation through repeated query positioning commands, in embodiment three, the reader does not need to send repeated query positioning commands; the tag can determine the corresponding operation of the slot counter based on its own clock. This reduces the reader's signaling overhead.

[0313] Example 4

[0314] Examples one through three all illustrate the tag's positioning operation as a reflection operation. In example four, the positioning operation after the tag enters the positioning state is a sequence transmission. Figure 19 The diagram illustrates a tag positioning process. The specific implementation of steps S1d-S5d can be found in steps S1b-S5b above. Taking the first electronic tag as an example, after the first electronic tag enters the positioning state, step S6d is executed, and a sequence is sent. This sequence can be pre-configured. The specific configuration method is as described above and will not be repeated here.

[0315] Optionally, the location sequence length is N bits. Since the mask field of the selection command has already selected bits mn from the location sequence, both the reader and the tag know the specific bit value of bits mn. Therefore, when the tag sends the location sequence to the reader, it can send bits other than bits mn out of the N bits. For example, if the location sequence length is 20 bits, and the mask field of the selection command selects bits 4-7 out of the 20 bits, then when the tag sends the location sequence to the reader, it only needs to send bits 1-3 and bits 8-20.

[0316] After receiving the corresponding sequence from the first electronic tag, the reader can identify the sender of the sequence based on the sequence. That is, the reader can blindly detect the sender of each sequence based on multiple received sequences. Furthermore, the reader can also execute S7d to send an acknowledgment message to the first electronic tag. Optionally, the acknowledgment message includes RN16.

[0317] Optionally, after receiving the confirmation message from the reader, the first electronic tag executes S8d, transitioning from the positioning state to the confirmation state. Alternatively, it can transition from the positioning state to another state, or exit the positioning state at another time.

[0318] Optionally, the first electronic tag also performs S9d and sends tag information to the reader, such as PC or EPC.

[0319] Taking the second electronic tag as an example, after receiving an acknowledgment message from the reader, the second electronic tag can execute S8e and enter the ready state from the positioning state. Alternatively, the second electronic tag can enter other states from the positioning state, or the second electronic tag can exit the positioning state at other times.

[0320] As can be seen, in certain scenarios, the tag positioning method of this application embodiment can complete both inventory and positioning during the inventory process. For example, some information of the tag (such as RN16) can be carried in the positioning sequence, and the reader can complete the tag positioning and determine RN16 through the blind detection positioning sequence.

[0321] Example 5

[0322] Unlike in Embodiments 1 to 4 where the reader indicates the tag to enter the positioning state via broadcast signaling, in Embodiment 5, the reader controls the tag to enter the positioning state via unicast signaling.

[0323] In this fifth embodiment, optionally, the tag has completed the inventory process. Optionally, the tag can be in an acknowledged state, an activated state, or a secure state before entering the positioning state.

[0324] Optionally, the unicast signaling used to indicate that a tag has entered the positioning state can carry tag-level (or user-level) dedicated parameters, which can be different for different tags. Tag-specific parameters can also be sent to the tag in other ways. For example, they can be carried in selection commands or other configuration information. Tag-specific parameters can include signal modulation methods, logic gate connection methods, etc.

[0325] The flowchart of the method in Example 5 includes: Figures 20 to 23 .in, Figure 20 , Figure 21 In the process shown, the label positioning operation is a reflection operation.

[0326] Specifically, Figure 20 In the illustrated process, the tag enters the positioning state at the moment it receives the indication signaling (i.e., the unicast positioning request). Alternatively, it can be understood that the tag enters the positioning state immediately after receiving the positioning request, without any delay. It should be noted that... Figure 20The location response shown can indicate that the tag agrees to or accepts the location request, or it can indicate that it refuses the location request. When the location response indicates that the location request is refused, the location response can carry a reason for refusal, such as that the tag is unaware of this type of location behavior.

[0327] Figure 20 In this example, method 1 for the tag to exit the positioning state involves the reader triggering the tag to exit the positioning state via a command. Method 2 involves the tag determining when it will exit the positioning state. Methods 1 and 2 for tag exiting the positioning state can also be found in the above embodiments and will not be repeated here. The dashed box only shows the positioning end command; in practice, other commands, such as a counting command (i.e., a third signaling), can also be used to trigger the tag to exit the positioning state via method 1.

[0328] Figure 21 In the illustrated process, after receiving a location request, the tag enters the location state after a delay. The start time for the tag to enter the location state can be dynamically indicated by the reader (corresponding to method 1), or the tag can enter the location state at a scheduled time (corresponding to method 2). For details on methods 1 and 2, please refer to the above embodiments. They will not be repeated here. The dashed box only shows a location timing request command. In practice, other commands, such as counting commands or other commands, can also be used to trigger the tag to enter the location state via method 1. For example, the reader first sends a command to the tag, informing it that it needs to enter the location state. After receiving this command, the tag prepares to enter the location state. Then, the reader sends another command to the tag, which triggers the tag to enter the location state.

[0329] It should be noted that tags in a positional state can receive high-priority commands, which can cause the tag's state to change. For example, Figure 20 In the process, the tag in the positioning state receives query commands (such as QueryNormal) from the reader and jumps from the positioning state to the arbitration state. Figure 21 In the process, the tag in the positioning state receives the SelectNormal command from the reader and jumps from the positioning state to the ready state.

[0330] Figure 22 , Figure 23 In the illustrated process, the tag's location operation involves sending a sequence. The tag can send the location sequence multiple times. The number of times it sends the sequence is determined by the tag itself or by the reader / writer. For example, Figure 22 In this process, the reader sends a message to the tag requesting a location sequence. Each time the tag receives this message, it sends a location sequence. Alternatively, the reader can send a message to the tag indicating the number of times to send a location sequence, and the tag will send the corresponding number of location sequences based on this message.

[0331] Optionally, the generation parameters related to the location sequence can be sent to the tag by the reader / writer.

[0332] Example 6

[0333] In Example 6, the reader controls the tag to enter the positioning state via multicast signaling. The flowchart of this method is as follows: Figure 24 As shown.

[0334] in, Figure 24 The multicast signaling shown can be a multicast positioning request (Positioning_RequestMultiCast). This message can carry identifiers for multiple labels. Optionally, the message is encrypted with group RN16. Optionally, the group RN16 can be configured separately for each label by the reader / writer via unicast signaling, or otherwise. Each label can have multiple group RN16s.

[0335] It should be noted that, in Embodiment Six, the tag can exit the positioning state in the following ways: Figure 24 As shown in Method 1 and Method 2, the reader can also trigger the tag's time slot counter to change through a counting command, so that the tag exits the positioning state when the time slot counter is zero.

[0336] It should also be noted that, Figure 24 Taking the tag location operation as an example, which is a reflection operation, the tag location operation can also be a sending sequence, which will not be elaborated here.

[0337] Compared to instructing tags to enter the positioning state via unicast, instructing tags to enter the positioning state via multicast can reduce the signaling overhead of the reader / writer.

[0338] In other embodiments, in unicast or multicast scenarios, the time for entering the positioning state can be pre-configured for the tag (e.g., 4 time slots). Thus, after receiving the first signaling, the tag enters the positioning state after a 4-time-slot delay.

[0339] It should be noted that the embodiments of this application do not limit the execution order of the various method steps.

[0340] The above mainly describes the solutions provided by the embodiments of this application from the perspective of interaction between various network elements. It is understood that the tags and readers described above, in order to achieve the above functions, include corresponding hardware structures and / or software modules for executing each function. Those skilled in the art should readily recognize that, in conjunction with the units and algorithm steps of the various examples described in the embodiments disclosed herein, this application can be implemented in hardware or a combination of hardware and computer software. Whether a function is executed by hardware or by computer software driving hardware depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0341] This application embodiment can divide the tag and reader into functional modules according to the above method example. For example, each function can be divided into a separate functional module, or two or more functions can be integrated into one processing unit. The integrated modules can be implemented in hardware or as software functional modules. It should be noted that the module division in this application embodiment is illustrative and only represents one logical functional division. In actual implementation, there may be other division methods.

[0342] For example, when dividing the functional modules using an integrated approach. Figure 25 A schematic diagram of a device 90 is shown. This device 90 can be a tag as described in the above embodiments, or a component supporting the tag's functionality as described in the above embodiments, such as circuitry within the tag. Alternatively, the device 90 can be a reader / writer as described in the above embodiments, or a component supporting the reader / writer's functionality as described in the above embodiments, such as a chip or circuitry within the reader / writer. This application does not specifically limit the device 90 in this regard.

[0343] Taking the tag in the above embodiment as an example, the state machine of the device 90 includes a positioning state, which is used to locate the device 90. The device 90 includes:

[0344] Transceiver unit 901 is used to receive a first signaling from the reader / writer; the first signaling is used to instruct, request, or control the device to enter a positioning state;

[0345] Processing unit 903 is configured to control the device to enter a positioning state in response to the first signaling.

[0346] The processing unit 903 is also configured to control the device to perform a positioning operation in the positioning state.

[0347] Optionally, the device may further include a storage unit 902 for storing data or instructions of the device 90.

[0348] Taking the reader / writer in the above embodiments as an example, device 90 includes:

[0349] Processing unit 903 is configured to determine a first signaling; the first signaling is configured to instruct, request, or control the electronic tag to enter a positioning state; the positioning state is configured to locate the electronic tag.

[0350] The transceiver unit 901 is used to send the first signaling.

[0351] Optionally, the device further includes a storage unit 902 for storing data or instructions of the device 90. For example, storing a first sequence.

[0352] All relevant content of each step involved in the above method embodiments can be referenced from the functional description of the corresponding functional module, and will not be repeated here.

[0353] In this embodiment, the device 90 is presented in an integrated manner, divided into various functional modules. These modules can refer to specific ASICs, circuits, processors and memories executing one or more software or firmware programs, integrated logic circuits, and / or other devices that can provide the aforementioned functions.

[0354] When device 90 is a tag, in a simplified embodiment, those skilled in the art will understand that device 90 can employ... Figure 12 The format shown. For example, the function / implementation process of transceiver unit 901 can be described through... Figure 12 The transmitting and receiving antennas in the middle are used to implement the function / implementation process of the processing unit 903, which can be achieved through the transmission antenna and the receiving antenna. Figure 12 It is implemented using the modulation module, encoding module, baseband processing unit, or other components.

[0355] Similarly, when device 90 is a reader / writer, the function / implementation process of the transceiver unit can be implemented by transmitting antenna and receiving antenna, and the function / implementation process of processing unit 903 can be implemented by processing chip or other components.

[0356] Since the apparatus provided in this application embodiment can be used to perform the above-described tag positioning method, the technical effects it can achieve can be referred to the above-described method embodiment, and will not be repeated here.

[0357] Optionally, embodiments of this application also provide a chip system, which includes a processor for supporting the communication device in implementing the aforementioned tag positioning method. In one possible design, the chip system further includes a memory. The memory is used to store necessary program instructions and data for the communication device. Of course, the memory may not be included in the chip system. The chip system may be composed of chips or may include chips and other discrete devices; embodiments of this application do not specifically limit this.

[0358] In the above embodiments, implementation can be achieved, in whole or in part, through software, hardware, firmware, or any combination thereof. When implemented using software programs, implementation can be, in whole or in part, in the form of a computer program product. This computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, all or part of the flow or function according to the embodiments of this application is generated. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions can be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another. For example, computer instructions can be transmitted from one website, computer, server, or data center to another via wired (e.g., coaxial cable, fiber optic, digital subscriber line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) means. The computer-readable storage medium can be any available medium accessible to a computer or a data storage device containing one or more servers, data centers, etc., that can be integrated with the medium. The available media can be magnetic media (e.g., floppy disks, hard disks, magnetic tapes), optical media (e.g., DVDs), or semiconductor media (e.g., solid-state disks, SSDs).

[0359] Although this application has been described herein in conjunction with various embodiments, those skilled in the art, by reviewing the accompanying drawings, disclosure, and appended claims, will understand and implement other variations of the disclosed embodiments in carrying out the claimed application. In the claims, the word "comprising" does not exclude other components or steps, and "a" or "an" does not exclude multiple instances. A single processor or other unit can implement several functions listed in the claims. While different dependent claims may recite certain measures, this does not mean that these measures cannot be combined to produce good results.

[0360] Although this application has been described in conjunction with specific features and embodiments, it is obvious that various modifications and combinations can be made thereto without departing from the spirit and scope of this application. Accordingly, this specification and drawings are merely exemplary illustrations of this application as defined by the appended claims, and are considered to cover any and all modifications, variations, combinations, or equivalents within the scope of this application. Clearly, those skilled in the art can make various alterations and modifications to this application without departing from the spirit and scope of this application. Thus, if such modifications and modifications of this application fall within the scope of the claims of this application and their equivalents, this application is also intended to include such modifications and modifications.

Claims

1. A tag positioning method, characterized in that, The method is applied to an electronic tag, wherein the state machine of the electronic tag includes a positioning state, the positioning state being used to position the electronic tag, and the method includes: The electronic tag receives a first signal from the reader; the first signal is used to instruct, request, or control the electronic tag to enter a positioning state. The electronic tag responds to the first signaling and enters the positioning state; The electronic tag performs a positioning operation in the positioning state.

2. The tag positioning method according to claim 1, characterized in that, The positioning operation includes: the electronic tag sending a first sequence to the reader or reflecting a modulated signal to the reader, wherein the modulated signal is a signal obtained by adding modulation information to the signal from the reader.

3. The tag positioning method according to claim 2, characterized in that, The first sequence sent by the electronic tag to the reader is multiple; and / or, the modulation signal sent by the electronic tag to the reader is multiple.

4. The tag positioning method according to claim 2 or 3, characterized in that, The first sequence includes a Gold sequence, or a Gray code, or a CAZAC sequence.

5. The tag positioning method according to any one of claims 1-4, characterized in that, The electronic tag responds to the first signaling and enters a positioning state, including: The electronic tag responds to the first signaling and enters the positioning state after a first time delay.

6. The tag positioning method according to any one of claims 1-5, characterized in that, After the electronic tag enters the positioning state, the method further includes: the electronic tag exits the positioning state after a second time delay.

7. The tag positioning method according to any one of claims 1-6, characterized in that, The method further includes: receiving configuration information from the reader; the configuration information includes any one or more of the following parameters: the connection method of the logic gate, the index of the connection method of the logic gate, or the connection pattern of the logic gate, the first sequence, the index corresponding to the first sequence, the parameters associated with the first sequence, and the first time period; The first parameter in the configuration information is carried in the fourth signaling, which includes either the first signaling or the second signaling; the second parameter in the configuration information is carried in the fifth signaling, which includes either the first signaling or the second signaling; the second signaling includes a selection command and a query command; the fourth signaling and the fifth signaling may be the same signaling or different signaling. The first parameter is a tag-level dedicated parameter; the dedicated parameter includes parameters available to the tag during the first time period; the second parameter is a reader-level common parameter.

8. The tag positioning method according to any one of claims 1-6, characterized in that, The method further includes: receiving configuration information from the reader; the configuration information includes a modulation scheme; the modulation scheme includes code division modulation and frequency modulation; when the modulation scheme is code division modulation, the configuration information also includes modulation symbols; when the modulation scheme is frequency modulation, the configuration information also includes a frequency hopping pattern; the configuration information also includes any one or more of the following: the connection method of logic gates, the index of the connection method of logic gates, or the connection pattern of logic gates, and a first time period; The first parameter in the configuration information is carried in the fourth signaling, which includes either the first signaling or the second signaling; the second parameter in the configuration information is carried in the fifth signaling, which includes either the first signaling or the second signaling; the second signaling includes a selection command and a query command; the fourth signaling and the fifth signaling may be the same signaling or different signaling. The first parameter is a tag-level dedicated parameter; the dedicated parameter includes parameters available to the tag during the first time period; the second parameter is a reader-level common parameter.

9. The tag positioning method according to any one of claims 1-8, characterized in that, The method further includes: The reader receives a first parameter R, which instructs the electronic tag to select a random number, wherein the random number is in the range (0, 2). R-1 The first parameter R is included in either the first signaling or the second signaling; the second signaling includes a selection command and a query command. The electronic tag responds to the first signaling and enters the positioning state after a first time delay, including: when the random number is zero, the electronic tag enters the positioning state; wherein, after receiving the first signaling, the random number is decremented by one every preset time interval.

10. The tag positioning method according to claim 9, characterized in that, The reader receives a third signaling message, which is used to trigger the random number of the electronic tag to be decremented by one.

11. The tag positioning method according to claim 10, characterized in that, The first signaling includes one or more of the following messages: unicast message, broadcast message, multicast message; the second signaling includes one or more of the following messages: unicast message, broadcast message, multicast message; the third signaling includes one or more of the following messages: unicast message, broadcast message, multicast message; the fourth signaling includes one or more of the following messages: unicast message, broadcast message, multicast message; the fifth signaling includes one or more of the following messages: unicast message, broadcast message, multicast message.

12. The tag positioning method according to any one of claims 1-11, characterized in that, The electronic tag entering the positioning state includes: the electronic tag entering the positioning state from the first state; The electronic tag exiting the positioning state includes: the electronic tag jumping from the positioning state to a second state; The first state includes any of the following states: ready, arbitration, response, confirmation, open, and secure; the second state includes any of the following states: ready, arbitration, response, confirmation, open, secure, and deactivated.

13. A tag positioning method, characterized in that, The method is applied to a reader / writer, and the method includes: The reader determines a first signal; the first signal is used to instruct, request, or control the electronic tag to enter a positioning state; the positioning state is used to locate the electronic tag; The reader sends the first signaling.

14. The tag positioning method according to claim 13, characterized in that, The method further includes: the reader receiving a first sequence or modulation signal from the electronic tag; The reader locates the electronic tag based on the first sequence or the modulation signal.

15. The tag positioning method according to claim 14, characterized in that, The first sequence carries tag information; the tag information includes a 16-bit random number or a pseudo-random number RN16; The reader receives a first sequence from the electronic tag in multiple ways; and / or, the reader receives a modulated signal from the electronic tag in multiple ways. The reader locates the electronic tag based on the first sequence or the modulation signal, including: the reader merges the plurality of first sequences and locates the electronic tag based on the merging result; Alternatively, the reader / writer may merge the multiple modulation signals and locate the electronic tag based on the merging result.

16. The tag positioning method according to claim 14 or 15, characterized in that, The first sequence includes a Gold sequence, or a Gray code, or a CAZAC sequence.

17. The tag positioning method according to any one of claims 13-16, characterized in that, The method further includes: sending configuration information; the configuration information includes any one or more of the following: the connection method of the logic gate, the index of the connection method of the logic gate, or the connection pattern of the logic gate, the first sequence, the index corresponding to the first sequence, the parameters associated with the first sequence, and the first time period; The first parameter in the configuration information is carried in the fourth signaling, which includes either the first signaling or the second signaling; the second parameter in the configuration information is carried in the fifth signaling, which includes either the first signaling or the second signaling; the second signaling includes a selection command and a query command; the fourth signaling and the fifth signaling may be the same signaling or different signaling. The first parameter is a tag-level dedicated parameter; the dedicated parameter includes parameters available to the tag during the first time period; the second parameter is a reader-level common parameter.

18. The tag positioning method according to any one of claims 13-16, characterized in that, The method further includes: sending configuration information; the configuration information includes a modulation scheme; the modulation scheme includes code division modulation and frequency modulation; when the modulation scheme is code division modulation, the configuration information also includes modulation symbols; when the modulation scheme is frequency modulation, the configuration information also includes a frequency hopping pattern; the configuration information also includes any one or more of the following: the connection method of logic gates, the index of the connection method of logic gates, or the connection pattern of logic gates, and a first time period; The first parameter in the configuration information is carried in the fourth signaling, which includes either the first signaling or the second signaling; the second parameter in the configuration information is carried in the fifth signaling, which includes either the first signaling or the second signaling; the second signaling includes a selection command and a query command; the fourth signaling and the fifth signaling may be the same signaling or different signaling. The first parameter is a tag-level dedicated parameter; the dedicated parameter includes parameters available to the tag during the first time period; the second parameter is a reader-level common parameter.

19. The tag positioning method according to any one of claims 13-18, characterized in that, The method further includes: Send the first parameter R to instruct the electronic tag to select a random number, the random number being in the range (0, 2). R-1 The first parameter R is included in the first signaling or the second signaling; the second signaling includes a selection command and a query command.

20. The tag positioning method according to claim 19, characterized in that, Send a third signaling message, which is used to trigger the decrement of the random number of the electronic tag by one.

21. The tag positioning method according to claim 20, characterized in that, The first signaling includes one or more of the following messages: unicast message, broadcast message, multicast message; the second signaling includes one or more of the following messages: unicast message, broadcast message, multicast message; the third signaling includes one or more of the following messages: unicast message, broadcast message, multicast message; the fourth signaling includes one or more of the following messages: unicast message, broadcast message, multicast message; the fifth signaling includes one or more of the following messages: unicast message, broadcast message, multicast message.

22. A tag positioning device, characterized in that, The state machine of the device includes a positioning state, which is used to position the device. The device includes: A transceiver unit is configured to receive a first signaling message from a reader / writer; the first signaling message is used to instruct, request, or control the device to enter a positioning state. A processing unit is configured to control the device to enter a positioning state in response to a first signaling instruction; The processing unit is also configured to control the device to perform a positioning operation in the positioning state.

23. The tag positioning device according to claim 22, characterized in that, The processing unit, used to control the device to perform positioning operations, includes controlling the transceiver unit to send a first sequence to the reader or to reflect a modulated signal to the reader.

24. The tag positioning device according to claim 23, characterized in that, The first sequence sent by the transceiver unit to the reader is multiple; and / or, the modulation signal sent by the transceiver unit to the reader is multiple.

25. The tag positioning device according to claim 23 or 24, characterized in that, The first sequence includes a Gold sequence, or a Gray code, or a CAZAC sequence.

26. The tag positioning device according to any one of claims 22-25, characterized in that, The processing unit, in response to a first signaling instruction, controls the device to enter a positioning state, including: In response to the first signaling, the device is controlled to enter a positioning state after a first time delay.

27. The tag positioning device according to any one of claims 22-26, characterized in that, The processing unit is also configured to control the device to exit the positioning state after a second time delay after the device enters the positioning state.

28. The tag positioning device according to any one of claims 22-27, characterized in that, The transceiver unit is further configured to receive configuration information from the reader / writer; the configuration information includes any one or more of the following: the connection method of the logic gates, the index of the connection method of the logic gates, or the connection pattern of the logic gates, the first sequence, the index corresponding to the first sequence, the parameters associated with the first sequence, and the first time period; The first parameter in the configuration information is carried in the fourth signaling, which includes either the first signaling or the second signaling; the second parameter in the configuration information is carried in the fifth signaling, which includes either the first signaling or the second signaling; the second signaling includes a selection command and a query command; the fourth signaling and the fifth signaling may be the same signaling or different signaling. The first parameter is a tag-level dedicated parameter; the dedicated parameter includes parameters available to the tag during the first time period; the second parameter is a reader-level common parameter.

29. The tag positioning device according to any one of claims 22-27, characterized in that, The transceiver unit is further configured to receive configuration information from the reader / writer; the configuration information includes a modulation scheme; the modulation scheme includes code division modulation and frequency modulation; when the modulation scheme is code division modulation, the configuration information also includes modulation symbols; when the modulation scheme is frequency modulation, the configuration information also includes a frequency hopping pattern; the configuration information also includes any one or more of the following: the connection method of logic gates, the index of the connection method of logic gates, or the connection pattern of logic gates, or a first time period; The first parameter in the configuration information is carried in the fourth signaling, which includes either the first signaling or the second signaling; the second parameter in the configuration information is carried in the fifth signaling, which includes either the first signaling or the second signaling; the second signaling includes a selection command and a query command; the fourth signaling and the fifth signaling may be the same signaling or different signaling. The first parameter is a tag-level dedicated parameter; the dedicated parameter includes parameters available to the tag during the first time period; the second parameter is a reader-level common parameter.

30. The label positioning device according to any one of claims 22-29, characterized in that, The transceiver unit is further configured to receive a first parameter R from the reader / writer, which instructs the electronic tag to select a random number, wherein the random number is in the range (0, 2). R-1 The first parameter R is included in the first signaling or the second signaling. The step of responding to the first signaling and entering the positioning state after a first time delay includes: entering the positioning state when the random number is zero; wherein, after receiving the first signaling, the random number is decremented by one every preset time interval.

31. The tag positioning device according to claim 30, characterized in that, The transceiver unit is also configured to receive a third signaling from the reader, the third signaling being used to trigger the random number of the electronic tag to be decremented by one.

32. The tag positioning device according to claim 31, characterized in that, The first signaling includes one or more of the following messages: unicast message, broadcast message, multicast message; the second signaling includes one or more of the following messages: unicast message, broadcast message, multicast message; the third signaling includes one or more of the following messages: unicast message, broadcast message, multicast message; the fourth signaling includes one or more of the following messages: unicast message, broadcast message, multicast message; the fifth signaling includes one or more of the following messages: unicast message, broadcast message, multicast message.

33. The tag positioning device according to any one of claims 27-32, characterized in that, Entering the positioning state includes: entering the positioning state from the first state; exiting the positioning state includes: jumping from the positioning state to the second state. The first state includes any of the following states: ready, arbitration, response, confirmation, open, and secure; the second state includes any of the following states: ready, arbitration, response, confirmation, open, secure, and deactivated.

34. A tag positioning device, characterized in that, include: Processing unit, used to determine the first signaling; The first signaling is used to instruct, request, or control the electronic tag to enter a positioning state; the positioning state is used to locate the electronic tag. The transceiver unit is used to send the first signaling.

35. The tag positioning device according to claim 34, characterized in that, The transceiver unit is also configured to receive a first sequence or modulated signal from the electronic tag; The processing unit is also configured to locate the electronic tag according to the first sequence or the modulation signal.

36. The tag positioning device according to claim 35, characterized in that, The transceiver unit receives a first sequence from the electronic tag, which may be a plurality of sequences; and / or, the transceiver unit receives a modulated signal from the electronic tag, which may be a plurality of signals. The processing unit is configured to locate the electronic tag based on the first sequence or the modulation signal, including: The multiple first sequences are merged, and the electronic tag is located based on the merging result. Alternatively, the multiple modulation signals can be merged, and the electronic tag can be located based on the merging result.

37. The tag positioning device according to claim 35 or 36, characterized in that, The first sequence includes a Gold sequence, or a Gray code, or a CAZAC sequence.

38. The label positioning device according to any one of claims 34-37, characterized in that, The transceiver unit is also used to send configuration information; the configuration information includes any one or more of the following: the connection method of the logic gate, the index of the connection method of the logic gate, or the connection pattern of the logic gate, the first sequence, the index corresponding to the first sequence, the parameters associated with the first sequence, and the first time period; The first parameter in the configuration information is carried in the fourth signaling, which includes either the first signaling or the second signaling; the second parameter in the configuration information is carried in the fifth signaling, which includes either the first signaling or the second signaling; the second signaling includes a selection command and a query command; the fourth signaling and the fifth signaling may be the same signaling or different signaling. The first parameter is a tag-level dedicated parameter; the dedicated parameter includes parameters available to the tag during the first time period; the second parameter is a reader-level common parameter.

39. The label positioning device according to any one of claims 34-37, characterized in that, The transceiver unit is also used to send configuration information; the configuration information includes a modulation method; the modulation method includes code division modulation and frequency modulation; when the modulation method is code division modulation, the configuration information also includes modulation symbols; when the modulation method is frequency modulation, the configuration information also includes a frequency hopping pattern; the configuration information also includes any one or more of the following: the connection method of logic gates, the index of the connection method of logic gates, or the connection pattern of logic gates, and a first time period; The first parameter in the configuration information is carried in the fourth signaling, which includes either the first signaling or the second signaling; the second parameter in the configuration information is carried in the fifth signaling, which includes either the first signaling or the second signaling; the second signaling includes a selection command and a query command; the fourth signaling and the fifth signaling may be the same signaling or different signaling. The first parameter is a tag-level dedicated parameter; the dedicated parameter includes parameters available to the tag during the first time period; the second parameter is a reader-level common parameter.

40. The label positioning device according to any one of claims 34-39, characterized in that, The transceiver unit is also used to send a first parameter R, which instructs the electronic tag to select a random number, wherein the random number is in the range (0, 2). R-1 The first parameter R is included in the first signaling or the second signaling.

41. The tag positioning device according to claim 40, characterized in that, The transceiver unit is also used to send a third signaling message, which is used to trigger the random number of the electronic tag to be decremented by one.

42. The tag positioning device according to claim 41, characterized in that, The first signaling includes one or more of the following messages: unicast message, broadcast message, multicast message; the second signaling includes one or more of the following messages: unicast message, broadcast message, multicast message; the third signaling includes one or more of the following messages: unicast message, broadcast message, multicast message; the fourth signaling includes one or more of the following messages: unicast message, broadcast message, multicast message; the fifth signaling includes one or more of the following messages: unicast message, broadcast message, multicast message.

43. A tag positioning device, characterized in that, It includes a processor and a memory, the processor and the memory being coupled, the processor being configured to implement the method as described in any one of claims 1-12, or the processor being configured to implement the method as described in any one of claims 13-21.

44. A tag positioning device, characterized in that, The device includes a processor and an interface circuit, the interface circuit being used to receive signals from other devices outside the device and transmit them to the processor or to send signals from the processor to other devices outside the device, the processor implementing the method as described in any one of claims 1-12 through logic circuits or executable code instructions, or the processor implementing the method as described in any one of claims 13-21 through logic circuits or executable code instructions.

45. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program or instructions that, when executed by a device, implement the method as described in any one of claims 1-12, or the method as described in any one of claims 13-21.

46. ​​A computer program product, characterized in that, The computer program product includes instructions that, when executed, implement the method as described in any one of claims 1-12, or implement the method as described in any one of claims 13-21.

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