CN109784434B

CN109784434B - Intelligent container and RFID (radio frequency identification) tag query and inventory method and system thereof

Info

Publication number: CN109784434B
Application number: CN201811548519.8A
Authority: CN
Inventors: 吕言勋; 李学文; 程可; 刘骏; 任国栋
Original assignee: Wormpex Technology Beijing Co Ltd
Current assignee: Superbox Technology Beijing Co ltd
Priority date: 2018-12-18
Filing date: 2018-12-18
Publication date: 2021-06-22
Anticipated expiration: 2038-12-18
Also published as: CN109784434A

Abstract

The invention relates to an intelligent container and an RFID (radio frequency identification) tag inquiring and checking method and system thereof, belonging to the technical field of intelligent containers. Selecting one or more RFID tags; sending the query command for multiple times at a first transmission power; and receiving a first type message returned in response to the query instruction transmitted at the first transmission power, wherein the byte number of the first type message is less than the byte number of a second type message returned in response to the inventory instruction. According to the invention, for some RFID tags with weak received signals caused by positions, tag performance and the like, when the inventory is not available in the normal inventory processing process, the inventory is performed by an inquiry method, so that the receiving and sending time duration of data is reduced, and the inventory efficiency of the RFID tags is improved.

Description

Intelligent container and RFID (radio frequency identification) tag query and inventory method and system thereof

Technical Field

The invention relates to the technical field of intelligent containers, in particular to an intelligent container and a method and a system for inquiring and checking RFID (radio frequency identification) tags of the intelligent container.

Background

The intelligent container identifies the sold goods through the RFID reader-writer and the RIFD tag, and brings new shopping experience for users. In the process of providing service, the intelligent container needs to count the commodities in the container under various scenes. For example, the commodities are checked regularly, and whether the commodities need to be added into the cabinet is determined; during the shopping process of the user, the commodities taken by the user are determined through checking to generate a shopping order.

In the checking process, due to the fact that the inner space of the container is narrow, the number and the types of commodities are numerous, and the influence of the limbs of a user on the positions of the commodities makes part of the tags difficult to receive signals sent by the reader-writer, and therefore the checking difficulty of the RIFD tags is caused. In order to ensure that reading is not missed, the reader-writer needs to count for multiple times, and actually most RIFD tags are counted for 1-2 times, and the whole counting time is prolonged because individual RIFD tags which are not easy to count are used.

Disclosure of Invention

Aiming at the technical problems in the prior art, the invention provides an intelligent container and an RFID (radio frequency identification) tag inquiring and checking method and system thereof, which are used for improving the checking efficiency of RFID tags.

According to one aspect of the invention, the invention provides an RFID label query method of an intelligent container, wherein the method comprises the following steps:

the RFID label query method of the intelligent container comprises the following steps:

selecting one or more RFID tags;

sending the query command for multiple times at a first transmission power; and

receiving a first type message returned in response to an inquiry command sent at a first transmission power, wherein the byte number of the first type message is less than the byte number of a second type message returned in response to a count command.

Preferably, the method for querying the RFID tag of the intelligent container further comprises: determining a number of messages of a first type returned in response to a query instruction sent at a first transmit power; when the number of the first type messages returned in response to the inquiry command sent at the first transmission power does not reach a first number threshold, the inquiry command is sent at a second transmission power for a plurality of times, wherein the second transmission power is different from the first transmission power.

Preferably, the method for querying the RFID tag of the intelligent container further comprises: determining a number of messages of the first type returned in response to the query instruction sent at the second power; when the number of the first type messages returned in response to the inquiry command sent at the second power does not reach a second number threshold, sending the inquiry command at a third transmission power for a plurality of times, wherein the third transmission power is different from the second transmission power; wherein the first quantity threshold is different from the second quantity threshold.

Preferably, in the method for querying the RFID tag of the intelligent container, one RFID tag is selected.

Preferably, in the method for querying the RFID tags of the intelligent container, one or more selected RFID tags are weak tags.

Preferably, in the method for querying an RFID tag of an intelligent container, the first type message is RN 16.

According to another aspect of the invention, the invention provides an RFID tag inventory method for an intelligent container, which comprises the following steps:

sending an inventory instruction to all RFID tags in the intelligent container;

determining that there are no RFID tags that have been inventoried; and

and inquiring one or more RFID labels which are not checked by adopting the RFID label inquiring method.

Preferably, the RFID tag inventory method of the intelligent container further comprises: when the RFID label query method is adopted, all RFID labels which are not checked are queried one by one or batch by batch.

According to another aspect of the invention, the invention provides an RFID tag inventory system of an intelligent container, which comprises:

one or more readers and writers configured to send a query instruction or an inventory instruction and receive a first type message returned by the RFID tags in the first set in response to the query instruction and a second type message returned by the RFID tags in the second set in response to the inventory instruction; the number of bytes of the first type message is smaller than that of the second type message, and the RFID tags in the first set are RFID tags which do not respond to the inventory instruction; and

a processor, coupled to the reader, configured to select one or more RFID tags in a first set; and instructing the one or more readers to send the query instruction for multiple times at the first transmission power.

Preferably, the processor is further configured to determine a number of messages of the first type returned in response to the query instruction sent at the first transmission power; and when the number of the first type messages returned in response to the query instruction sent at the first transmission power does not reach a first number threshold value, instructing the one or more readers to send the query instruction at a second transmission power for multiple times, wherein the second transmission power is different from the first transmission power.

Preferably, the processor is further configured to instruct the one or more readers to send the query instruction at a third transmission power for a plurality of times in response to the number of the first type messages returned by the query instruction sent at the second transmission power not reaching a second number threshold, wherein the third transmission power is different from the second transmission power; wherein the first quantity threshold is different from the second quantity threshold.

Preferably, the processor is further configured to instruct the one or more readers to send an inventory instruction to all RFID tags within the intelligent container; and determining that no RFID tags are inventoried as a first set of RFID tags.

Preferably, the processor is further configured to select RFID tags in the first set one by one or in batches.

According to another aspect of the invention, the invention provides an intelligent container which comprises the RFID tag inventory system.

In the RFID tag query method provided by the invention, the received response message is a first type message with the byte number less than that of a second type message returned in response to the inventory instruction, such as RN16, so that the time length used by the RFID tag in transmitting and receiving data is far less than the time length used in normal inventory. When the RFID label checking method is used for checking normally, the RFID label which cannot be checked during normal checking can be quickly checked by using the checking method, so that the checking efficiency of the RFID label is improved.

Drawings

Preferred embodiments of the present invention will now be described in further detail with reference to the accompanying drawings, in which:

FIG. 1 is a flow chart of a method of RFID tag interrogation of an intelligent container according to one embodiment of the invention;

FIG. 2 is a flow chart of a RFID tag inventory method according to one embodiment of the invention;

FIG. 3 is a flow diagram of a query process for an RFID tag according to one embodiment of the present invention;

FIG. 4 is a schematic diagram of signal transmission when a reader interacts with an RFID tag according to one embodiment of the present invention; and

FIG. 5 is a schematic block diagram of an intelligent container according to one embodiment of the invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

In the following detailed description, reference is made to the accompanying drawings that form a part hereof and in which is shown by way of illustration specific embodiments of the application. In the drawings, like numerals describe substantially similar components throughout the different views. Various specific embodiments of the present application are described in sufficient detail below to enable those skilled in the art to practice the teachings of the present application. It is to be understood that other embodiments may be utilized and structural, logical or electrical changes may be made to the embodiments of the present application.

FIG. 1 is a flow chart of a method of RFID tag interrogation of an intelligent container according to one embodiment of the invention. In the present embodiment, the transmission power is set to W_iAnd i is the query frequency and is preset to be M times. The specific query method comprises the following steps:

in step S1, the RFID tag to be queried is selected, one or more RFID tags may be selected.

In step S2, the value of i is set to 1.

Step S3, adjusting the transmitting power W_iIs an appropriate value, which is the first transmission power W₁So that the RFID tag can receive the issued inquiry command.

Step S4, transmitting power W_i(first transmission power W in this step)₁) The query is sent multiple times. The number of times of sending the query instruction can be set according to actual conditions, such as 50 times, 80 times and the like.

Step S5, receiving response with transmitting power W_iThe sent query instruction returns a first type message, wherein the byte number of the first type message is less than the byte number of a second type message returned in response to the inventory instruction. In this embodiment, after receiving the query instruction, the RFID tag returns a first type message responding to the query instruction, where the number of bytes of the first type message is smaller than the number of bytes of a second type message returned by the RFID tag in response to the inventory instruction. Therefore, the time length for receiving the first type message is less than the time length for receiving the second type message, and the time length for sending the first type message by the RFID tag is also less than the time length for sending the second type message, so according to the scheme provided by this embodiment, the time length for querying the RFID tag is far less than the time length for normally checking the RFID tag.

In order to ensure the accuracy of the query, in an embodiment, the method further includes:

step S6, determining response with transmitting power W_iNumber N of messages of the first type returned by a transmitted query_i,. In this step, since i is 1, the number N is set to_iIs a number N₁. Since the query instruction is transmitted a plurality of times in step S4, the returned first type message may be received a plurality of times in step S5, and in this step, the number N of returned first type messages is counted₁。

Step S7, determining the number N of first type messages returned in response to the query command sent at the transmission power₁Whether a number threshold K is reached_iIn this step, the number threshold K_iIs a first number threshold K₁If the first number threshold K is not reached₁Step S8 is executed; if the first number threshold K is reached₁Then it is determined in step S11 that the RFID tag is interrogated and the interrogation is finished.

In step S8, it is determined whether i is equal to the preset number M, i.e., whether a preset number query is currently performed. If not, step S9 is performed, and if so, the query is determined to be failed in step S10, ending the query.

In step S9, the sequence number i is incremented by 1, and then the process returns to step S3. And adjusting the transmitting power and carrying out a new round of inquiry process.

During the process of querying an RFID tag, if the first query is not successful, the transmit power is adjusted at the next query to increase the likelihood that the RFID tag receives a signal. Wherein the transmission power corresponds to the first transmission power W in turn₁A second transmission power W₂A third transmission power W₃… … are provided. In these transmission power sequences, adjacent transmission power values are different. Correspondingly, the times of sending the query command corresponding to each transmission power can be the same or different; number threshold K for determining the number of messages returned of the first type_iThe number threshold of neighbors is different in the sequence. For example, the second transmit power is different than the first transmit power, the third transmit power is different than the second transmit power, and the first quantity threshold is different than the second quantity threshold.

When there are multiple RFID tags to be queried, the query can be performed in batches, and one or more RFID tags are selected in each batch. Preferably, only one weak label is selected in each inquiry, especially, only one weak label is selected in each inquiry, so that the influence of other signals on the weak label is avoided, and the inquiry rate of the weak label is increased. The weak tag is an RFID tag with weak signal response capability due to position or performance.

In the above embodiments of interrogating RFID tags, the first type of message may be RN16 and the second type of message may be EPC (product code) information.

Fig. 2 is a flowchart illustrating an RFID tag inventory method according to an embodiment of the invention. The method specifically comprises the following steps:

and S100, initiating first checking to all RFID tags in the intelligent container. The RFID tag information used to identify the goods in the intelligent container is known, for example stored in a memory in the intelligent container, or stored in a remote server. When the intelligent container checks the RFID tag in the container, the processor of the intelligent container controls the reader-writer to send out a wireless signal, and the reader-writer carries a checking instruction. And the RFID tag in the cabinet receives the wireless signal, responds to the inventory instruction therein, sends tag information of the RFID tag, mainly EPC information, namely a product code, and determines to inventory the RFID tag when receiving the EPC information.

Step S200, determining that no checked RFID label exists. After the first counting is finished, comparing the current counted tag information with the pre-counting tag information, and determining that no counted RFID tag exists. For example, the total number of 100 RFID tags tag1, tag2 and tag3 … … tag100 in the container before inventory, tag1, tag2 and tag3 … … tag90 are obtained after the first inventory, and after comparison, 10 RFID tags tag91, tag92 and tag93 … … tag100 are not inventoried. Thus, through the first inventory, the RFID tags within the container are divided into two sets: the non-inventoryed RFID tags are in a first set and the inventoryed RFID tags are in a second set.

And step S300, aiming at the RFID tags in the first set, performing secondary inventory by adopting a tag query method. In this embodiment, the RFID tags in the first set are typically weak tags, and have a signal response capability that is weaker than the RFID tags that were first checked out, either for location reasons or performance reasons. In order to prevent confusion or signal interference when performing a secondary inventory, only one RFID tag is interrogated per interrogation. The process of querying an RFID tag is shown in fig. 3:

step S301, adjusting the transmitting power of the reader-writer. Since some RFID tags that cannot be checked cannot be activated because they cannot receive continuous wave radiation due to their positions, etc., and cannot respond to the checking instruction, the transmission power of the reader/writer is adjusted to be greater than that used for the first checking in order to improve the response capability of the RFID tags during the second checking. However, if the transmission power is too large, the reflected power is also large, which results in too high a reception error rate and failure to check the RFID tag. Thus, a suitable transmit power may be determined by trial and error.

Step S302, selecting the RFID label needing to be checked. To prevent confusion, only one RFID tag is selected in this embodiment. Specifically, the purpose of selecting which RFID tag can be achieved by the setting of the assert flag bit in the select instruction.

Step S303, sending a query instruction to the selected RFID tag, and receiving a temporary password RN16 returned by the RFID tag, where in this embodiment, RN16 is used as the first type message. The query instruction is used as the query instruction. Fig. 4 is a schematic diagram of signal transmission when the reader/writer interacts with the RFID tag. In the figure, the first action is a message sent by the reader-writer, and the second action is a message returned by the RFID tag. The message sent by the reader-writer comprises a select instruction, and then the query instruction and the NAK instruction are repeatedly sent. The message returned by the RFID tag includes RN 16. Normally, each time the RFID tag receives the query command, it sends RN16 as a temporary password to the reader/writer. However, due to component occlusion or the like, if the RFID tag does not receive the query instruction, the RN16 will not be transmitted.

Step S304, determining whether the query command has been sent for a set number of times, for example, 50 times, if the number of times of sending the query command has reached the set number of times, going to step S305, and if the number of times of sending the query command has not reached the set number of times, returning to step S303 to continue sending the query command.

In step S305, the number of times RN16 is received is counted.

Step S306, determine whether the number of received RNs 16 reaches a number threshold, for example, 5. If the number of received RNs 16 is greater than or equal to 5, confirming the query to the RFID tag in step S309 and ending the process of querying the RFID tag; if the number of the cells does not reach 5, the process goes to step S307.

Step S307, determine whether the predetermined number of queries, such as 10 queries, is reached. If not, go to step S301, readjust the transmission power, and perform the next query. If the number of inquiries has been reached, i.e., the transmission power has been changed 10 times, 10 inquiries are made, it is confirmed that the RFID tag has not been inquired at step S308.

Step S400, determining whether all the RFID tags in the first set are queried, and if all the RFID tags in the first set are queried, completing the checking; if the RFID tags are not inquired, the step S300 is returned to continue the inquiry.

In this embodiment, for those RFID tags whose received signals are weak due to location, tag performance, and the like, when the inventory is not available in the normal inventory processing process, an inquiry method is adopted, and instead of using the EPC information of the RFID tags as the criterion for determining whether inventory is available, the RN16 whose received number is greater than the number threshold is used as the criterion. Since the data size of EPC information (typically 64 bytes) is much larger than that of RN16 (2 bytes), the present embodiment improves the inventory efficiency. In order to ensure the inventory accuracy of this embodiment, in this embodiment, a query instruction is sent for multiple times, for example, 50 times, but may also be 20 times, 30 times, 80 times, and the like, and generally any one of the 20 to 100 times may be taken. The present embodiment also sets a quantity threshold for determining whether RN16 is received, such as the aforementioned 5. For example, if 50 query instructions were sent with at least 5 RNs 16 received back, it can be determined that the RFID tag is indeed present.

FIG. 5 is a schematic diagram of the intelligent container according to one embodiment of the present invention. The intelligent container includes an RFID tag inventory system and a plurality of RFID tags 300. The RFID tag inventory system includes a processor 100 and a reader/writer 200, where the processor 100 is connected to the reader/writer 200 and configured to select one or more RFID tags and instruct the corresponding reader/writer 200 to send a query command or an inventory command. The number of the reader/writers 200 may be one or more, and as shown in the figure, the embodiment includes 2 reader/writers 200. The reader 200 is configured to transmit a query instruction and an inventory instruction, and receive a first type message returned by the RFID tag 300 in response to the query instruction and a second type message returned in response to the inventory instruction, wherein the number of bytes of the first type message is smaller than the number of bytes of the second type message. The RFID tag 300 is attached to an article and has a product code (EPC information) stored in a memory thereof for identifying the article.

In order to store data, the system further comprises a memory 400 for storing the inventory, various parameters required in the query process, such as the first set number and the second set number, and other intermediate data.

The RFID tag checking system in this embodiment implements checking of the RFID tag in the intelligent container according to the flow shown in fig. 2 and fig. 3. For example:

when the RFID tags in the intelligent container are checked, the processor 100 selects all the RFID tags in the container and controls the reader-writer 200 to send out a checking instruction.

And the RFID tag receiving the checking instruction in the cabinet responds to the checking instruction and sends tag information of the checking instruction.

After receiving the tag information, the reader 200 sends the tag information to the processor 100.

At the end of the inventory, the processor 100 compares the pre-inventory and post-inventory tag information to determine that there are no RFID tags inventoried, i.e., to determine a first set of RFID tags.

The processor 100 selects an RFID tag in the first set, and controls the reader 200 to transmit a plurality of query commands at the first transmission power, for example, 50 times.

The RFID tag returns to RN16 in response to the query instruction.

After receiving the RN16, the reader 200 sends it to the processor 100.

Processor 100 counts the number of RNs 16 received and determines whether a number threshold, such as 5, has been reached. If the number of received RNs 16 is greater than or equal to 5, judging that the RFID tags are inquired; if the number of the received RNs 16 is less than 5, an instruction is sent to the reader-writer, the reader-writer 200 adjusts the transmission power, and resends the query instruction for multiple times with the second transmission power until the RFID tag is judged to be queried or the preset query times are reached, such as 10 times. The query for the RFID tag is ended.

After the query of the current RFID tag is finished, the rest RFID tags in the first set are queried one by one according to the same query flow, and then one-time complete inventory is finished.

In the query process, the RFID tags may also be selected in batches for querying, for example, two or three RFID tags are selected at the same time during the first query, so as to improve the query speed.

The details of the inquiry and inventory process and the setting of specific parameters thereof, such as the setting of each time of transmitting power, the setting of the quantity threshold used for judging the quantity of the RN16 in each inquiry process, etc., are the same as the aforementioned method, and have been described in detail in the method, so that the description is not repeated here.

The above embodiments are provided only for illustrating the present invention and not for limiting the present invention, and those skilled in the art can make various changes and modifications without departing from the scope of the present invention, and therefore, all equivalent technical solutions should fall within the scope of the present invention.

Claims

1. An RFID tag inventory method of an intelligent container, comprising the following steps:

sending an inventory instruction to all RFID tags in the intelligent container;

determining that there are no RFID tags that have been inventoried;

selecting one or more of the RFID tags;

sending the query command for multiple times at a first transmission power; and

receiving a first type message returned in response to an inquiry instruction sent at a first transmission power, wherein the byte number of the first type message is less than the byte number of a second type message returned in response to an inventory instruction;

the time length for receiving the first type message is shorter than the time length for receiving the second type message, and the time length for sending the first type message by the RFID tag is shorter than the time length for sending the second type message; wherein the RFID tag that is not checked is a weak tag.

2. The RFID tag inventory method of intelligent containers of claim 1, further comprising: determining a number of messages of a first type returned in response to a query instruction sent at a first transmit power; when the number of the first type messages returned in response to the inquiry command sent at the first transmission power does not reach a first number threshold, the inquiry command is sent at a second transmission power for a plurality of times, wherein the second transmission power is different from the first transmission power.

3. The RFID tag inventory method of intelligent containers of claim 2, further comprising: determining a number of messages of the first type returned in response to the query instruction sent at the second transmit power; when the number of the first type messages returned in response to the query instruction sent at the second transmission power does not reach a second number threshold, sending the query instruction at a third transmission power for multiple times; wherein the third transmit power is different from the second transmit power, and the first quantity threshold is different from the second quantity threshold.

4. The RFID tag inventory method of intelligent containers of claim 1, wherein one RFID tag is selected.

5. The RFID tag inventory method of intelligent containers of claim 1, wherein the selected one or more RFID tags are weak tags.

6. The intelligent container RFID tag inventory method of claim 1, wherein the first type of message is RN 16.

7. The RFID tag inventory method of intelligent containers of claim 1, further comprising: querying all RFID tags which are not checked one by one or in batches by using the RFID tag querying method of any one of claims 1 to 6.

8. An RFID tag inventory system for an intelligent container, comprising:

one or more readers and writers, wherein the readers and writers are configured to send inquiry instructions and inventory instructions, and receive first type messages returned by the RFID tags in the first set in response to the inquiry instructions and second type messages returned by the RFID tags in the second set in response to the inventory instructions; the number of bytes of the first type message is smaller than that of the second type message, and the RFID tags in the first set are RFID tags which do not respond to the inventory instruction; the time length for receiving the first type message is shorter than the time length for receiving the second type message, and the time length for sending the first type message by the RFID tag is shorter than the time length for sending the second type message; and

a processor, coupled to the reader, configured to select one or more RFID tags in a first set; instructing the one or more readers to send the query instruction for multiple times at a first transmission power;

wherein the first set is an unrated RFID tag, which is a weak tag.

9. The intelligent container RFID tag inventory system of claim 8, wherein the processor is further configured to determine a number of first type messages returned in response to the query instruction sent at the first transmit power; and when the number of the first type messages returned in response to the query instruction sent at the first transmission power does not reach a first number threshold value, instructing the one or more readers to send the query instruction at a second transmission power for multiple times, wherein the second transmission power is different from the first transmission power.

10. The intelligent container RFID tag inventory system of claim 9, wherein the processor is further configured to instruct the one or more readers to send the query instruction a plurality of times at a third transmit power in response to the number of first type messages returned by the query instruction sent at the second transmit power not reaching a second number threshold; wherein the third transmit power is different from the second transmit power, and the first quantity threshold is different from the second quantity threshold.

11. The RFID tag inventory system of the intelligent container of claim 8, wherein the processor is further configured to instruct the one or more readers to send inventory instructions to all RFID tags within the intelligent container; and determining that no RFID tags are inventoried as a first set of RFID tags.

12. The intelligent container RFID tag inventory system of claim 8, wherein the processor is further configured to select the RFID tags in the first set one by one or in batches.

13. An intelligent container comprising the RFID tag inventory system of any of claims 8-12.