Logistics guarantee positioning method and system based on RFID

Abstract

The invention belongs to the technical field of military logistics guarantee, and particularly discloses a logistics guarantee positioning method and system based on RFID, and the method comprises the steps: respectively reading the signal intensity values of a reference tag at a fixed position and a to-be-determined tag at a to-be-determined position through an RFID reader; comparing the signal intensity values of the reference labels with the signal intensity values of the to-be-determined labels to obtain a plurality of reference labels closest to the to-be-determined labels; and estimating the coordinates of the to-be-positioned label by adopting a weight empirical formula according to the plurality of obtained reference labels closest to the to-be-positioned label.

Description

Technical Field

[0001] The present invention belongs to the technical field of military logistics support, and in particular relates to a logistics support positioning method and system based on RFID. Background Art

[0002] Automatic identification technology is an important method and means to realize the automatic collection, reading, transmission, analysis and processing of information data. It has good accuracy, high efficiency and good compatibility. It can realize automatic data collection, eliminate human errors and greatly improve the accuracy and reliability of data collection. RFID (Radio Frequency Identification) technology is a kind of automatic identification technology. It has a large storage capacity for data and can use low frequency, high frequency, ultra-high frequency, microwave and other methods to realize non-contact collection of target information. It can work in harsh environments and can adapt to dust coverage, oil pollution, mechanical vibration and cover. It can effectively prevent the common barcode labels from being easily polluted and torn. In addition, the RFID reader also has the characteristics of reading multiple labels at the same time, and the operation is simple and fast. In terms of military logistics, our army is currently making great strides from mechanization and semi-mechanization to informatization. The war form under informatization conditions has shifted from traditional linear operations to non-linear operations. The troops are rapidly transferred to battle, and the material consumption is large. The war will be unprecedentedly fierce. The battlefield environment under information conditions requires that military logistics support must be timely, accurate in quantity and accurate in location, that is, the specified quantity of materials must be delivered to the specified location at the specified time, which puts forward higher requirements on the accuracy and speed of our military logistics supply. The original material support system and model are no longer applicable. Therefore, it is urgent to propose a logistics support positioning method based on RFID to solve the above technical problems. Summary of the invention

[0003] The present invention provides a logistics support positioning method and system based on RFID, which are used to solve the problem of inaccurate positioning of military logistics materials when they are stored or taken out.

[0004] In a first aspect, a logistics support indoor positioning method based on RFID is provided, the method comprising:

[0005] Using a radio frequency identification (RFID) reader, the signal strength values ​​of the reference tag at a fixed position and the pending tag at a pending position are read respectively;

[0006] Compare the signal strength values ​​of the reference tag and the tag to be determined, and obtain a number of reference tags closest to the tag to be determined;

[0007] Based on the obtained reference tags closest to the tag to be located, the coordinates of the tag to be located are estimated using a weighted empirical formula.

[0008] In a second aspect, a logistics support indoor positioning system based on RFID is provided, the system comprising:

[0009] The intensity value acquisition module is used to use a wireless radio frequency identification RFID reader to read the intensity values ​​of the reference tag at a fixed position and the to-be-determined tag signal at a to-be-determined position respectively;

[0010] A comparison module, used to compare the signal strength values ​​of the reference tag and the tag to be determined, and obtain a number of reference tags closest to the tag to be determined;

[0011] The coordinate acquisition module is used to estimate the coordinates of the tag to be located by using a weighted empirical formula based on a number of reference tags that are closest to the tag to be located.

[0012] An RFID-based logistics support positioning method and system provided in an embodiment of the present invention uses a reference tag at a fixed position to achieve auxiliary positioning, compares the signal strength value (RSSI) of the fixed reference tag with the signal strength value (RSSI) of the tag to be positioned, and adopts the "nearest neighbor distance" weight method to calculate the coordinates of the tag to be positioned. This method uses a convenient electronic tag to replace an expensive reader, and because the tag to be positioned and the reference tag are in the same environment, the reference information can be dynamically updated in real time, which can offset the influence of many environmental factors. While ensuring accuracy, the deployment cost of the system can be reduced, and the location information is more accurate and reliable.

[0013] Other features and advantages of the present invention will be described in the following description, and partly become apparent from the description, or be understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained by the structures particularly pointed out in the written description, claims, and drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] The drawings described herein are used to provide a further understanding of the present invention and constitute a part of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0015] Figure 1 A schematic diagram of an implementation process of a logistics support positioning method based on RFID according to an embodiment of the present invention;

[0016] Figure 2 A schematic diagram of tag deployment provided according to an embodiment of the present invention. DETAILED DESCRIPTION

[0017] In order to make the purpose, technical solutions and advantages of this specification more clear, the technical solutions of this specification will be clearly and completely described below in combination with the specific embodiments of this specification and the corresponding drawings. Obviously, the described embodiments are only part of the embodiments of this specification, not all of the embodiments. Based on the embodiments in this specification, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this specification.

[0018] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, device, product or equipment that includes a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or equipment.

[0019] The technical solutions provided by the embodiments of this specification are described in detail below in conjunction with the accompanying drawings.

[0020] In order to improve the accuracy of material location positioning, the embodiment of the present invention provides a logistics support positioning method and system based on RFID.

[0021] Figure 1 FIG. 1 is a schematic diagram of an implementation flow of a logistics support positioning method based on RFID according to an embodiment of the present invention. Figure 1 , the method comprising:

[0022] S100: using a radio frequency identification (RFID) reader to read the signal strength values ​​of a reference tag at a fixed position and a tag to be determined at a to-be-determined position respectively;

[0023] S102: Compare the signal strength values ​​of the reference tag and the tag to be determined, and obtain a number of reference tags closest to the tag to be determined;

[0024] S104: according to the obtained reference tags closest to the tag to be located, the coordinates of the tag to be located are estimated using a weighted empirical formula.

[0025] In one embodiment, see Figure 2 , the number of the RFID readers is m; the number of the reference tags is n; the number of the pending tags is u;

[0026] The method of using an RFID reader to respectively read the strength values ​​of the reference tag at a fixed position and the signal of the pending tag at the pending position specifically includes:

[0027] The signal strength of n reference tags at fixed positions is read by an RFID reader, and the signal strength vector is as follows:

[0028] θ=(θ1,θ2,...,θ n );

[0029] In the formula, θ i represents the value of the reference tag on reader i;

[0030] The RFID reader is used to read the signal strength of u undetermined tags at the undetermined position, and the signal strength vector is obtained as follows:

[0031] S=(S1,S2,...,S u );

[0032] In the formula, S i Indicates the value of the tag to be located on reader i.

[0033] In a specific implementation manner, comparing the signal strength values ​​of the reference tag and the tag to be located to obtain a number of reference tags closest to the tag to be located specifically includes:

[0034] According to the obtained signal strength vector of the reference tag and the signal strength vector of the tag to be located, the Euclidean distance between the two is calculated according to the following formula:

[0035]

[0036] Each label to be located gets a vector:

[0037] E=(E1,E2,...,E n );

[0038] The smaller the E value is, the closer the distance between the reference tag and the tag to be located is, and then k reference tags with the closest signal strength to the tag to be located are obtained.

[0039] In a specific implementation, the method of estimating the coordinates of the tag to be located by using a weighted empirical formula based on the obtained reference tags closest to the tag to be located specifically includes:

[0040] Based on the k reference tags that are closest to the tag to be located, the coordinates of the tag to be located are estimated using the weighted empirical formula as follows:

[0041]

[0042] Wherein, W i is the weight of the i-th nearest neighbor reference tag (i = 1, 2, 3, …, k, k < n, and k is the smallest k neighbors among the n Euclidean distances E j ); (x i , y i ) is the position corresponding to the i-th reference tag; wherein, W i is obtained by using the following empirical formula:

[0043]

[0044] In a specific embodiment, the signal strength value is obtained by acquiring the signal strength values within a period of time T, sorting the strength values, retaining the top k strength values with the highest strength, discarding the remaining (n - k) values, and taking the average value as the final signal strength value, which specifically includes:

[0045] Obtain the sorted strength values of the RSSI values of the tags from largest to smallest within the specified time T according to the following formula:

[0046] R i = (R i1 , R i2 ,..., R ik ,..., R id );

[0047] Obtain the average value of the strength values as the final signal strength value according to the acquired sorted strength values according to the following formula:

[0048]

[0049] Wherein, n is the total number of tags processed, and d is the number of signal strength values read for the same tag within the specified time.

[0050] A logistics guarantee positioning method based on RFID provided by an embodiment of the present invention uses reference tags at fixed positions to achieve assisted positioning, compares the signal strength values (RSSI) of the fixed reference tags with the signal strength values (RSSI) of the tags to be positioned, and uses the "nearest neighbor distance" weight method to calculate the coordinates of the tags to be positioned. This method uses inexpensive electronic tags to replace expensive readers, and since the tags to be positioned and the reference tags are in the same environment, the reference information can be updated dynamically in real time, many environmental factors can be offset, the deployment cost of the system can be reduced while ensuring accuracy, and the position information is more accurate and reliable.

[0051] Based on the same inventive concept, the present invention also provides a logistics guarantee positioning system based on RFID, and the system includes:

[0052] The intensity value acquisition module is used to use a wireless radio frequency identification RFID reader to read the intensity values ​​of the reference tag at a fixed position and the to-be-determined tag signal at a to-be-determined position respectively;

[0053] A comparison module, used to compare the signal strength values ​​of the reference tag and the tag to be determined, and obtain a number of reference tags closest to the tag to be determined;

[0054] The coordinate acquisition module is used to estimate the coordinates of the tag to be located by using a weighted empirical formula based on a number of reference tags that are closest to the tag to be located.

[0055] In a specific implementation, the number of the RFID readers is m; the number of the reference tags is n; the number of the tags to be located is u;

[0056] The intensity value acquisition module is specifically used for:

[0057] The signal strength of n reference tags at fixed positions is read by an RFID reader, and the signal strength vector is as follows:

[0058] θ=(θ1,θ2,...,θ n );

[0059] In the formula, θ i represents the value of the reference tag on reader i;

[0060] The RFID reader is used to read the signal strength of u undetermined tags at the undetermined position, and the signal strength vector is obtained as follows:

[0061] S=(S1,S2,...,S u );

[0062] In the formula, S i Indicates the value of the tag to be located on reader i.

[0063] In a specific implementation, the comparison module is specifically used to:

[0064] Based on the obtained signal strength vector of the reference tag and the signal strength vector of the tag to be located, the Euclidean distance between the two is calculated according to the following formula:

[0065]

[0066] Each label to be located gets a vector:

[0067] E=(E1,E2,...,E n );

[0068] The smaller the value of E, the closer the reference tag is to the tag to be located. Then, k reference tags with the signal strength closest to the tag to be located are obtained.

[0069] In a specific embodiment, the coordinate acquisition module is specifically configured to:

[0070] According to the k reference tags closest to the tag to be located obtained, the coordinates of the tag to be located are estimated by using the weight empirical formula as follows:

[0071]

[0072] In the formula, W i is the weight of the i-th nearest neighbor reference tag (i = 1, 2, 3,..., k, k < n, and k is the k neighbors with the smallest Euclidean distances E j ); (x i , y i ) is the position corresponding to the i-th reference tag; among them, W i is obtained by using the following empirical formula:

[0073]

[0074] In a specific embodiment, the signal strength value is obtained by obtaining the signal strength values within a period of time T, sorting the strength values, retaining the top k strength values with the highest strength, discarding the remaining (n - k) values, and taking the average value as the final signal strength value, which specifically includes:

[0075] Obtain the sorted strength values of the RSSI values of the tag within the specified time T from large to small according to the following formula:

[0076] R i = (R i1 , R i2 ,..., R ik ,..., R id );

[0077] According to the obtained sorted strength values, obtain the average value of the strength values as the final signal strength value according to the following formula:

[0078]

[0079] Among them, n is the total number of tags processed, and d is the number of signal strength values read for the same tag within the specified time.

[0080] An RFID-based logistics support positioning system provided by an embodiment of the present invention uses a reference tag at a fixed position to achieve auxiliary positioning, compares the signal strength value (RSSI) of the fixed reference tag with the signal strength value (RSSI) of the tag to be positioned, and adopts the "nearest neighbor distance" weight method to calculate the coordinates of the tag to be positioned. This method uses a convenient electronic tag to replace an expensive reader, and because the tag to be positioned and the reference tag are in the same environment, the reference information can be dynamically updated in real time, which can offset the influence of many environmental factors. While ensuring accuracy, the deployment cost of the system can be reduced, and the location information is more accurate and reliable.

[0081] Although the preferred embodiments of the present invention have been described, those skilled in the art may make additional changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present invention.

[0082] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A logistics support positioning method based on RFID, characterized in that: The method comprises: Using a radio frequency identification (RFID) reader, the signal strength values ​​of the reference tag at a fixed position and the pending tag at a pending position are read respectively; Compare the signal strength values ​​of the reference tag and the tag to be determined, and obtain a number of reference tags closest to the tag to be determined; Based on the obtained reference tags closest to the tag to be located, the coordinates of the tag to be located are estimated using a weighted empirical formula.

2. The method according to claim 1, characterized in that The number of the RFID readers is m; the number of the reference tags is n; the number of the pending tags is u; The method of using an RFID reader to respectively read the strength values ​​of the reference tag at a fixed position and the signal of the pending tag at the pending position specifically includes: The signal strength of n reference tags at fixed positions is read by an RFID reader, and the signal strength vector is as follows: θ=(θ1,θ2,...,θ n ); In the formula, θ i represents the value of the reference tag on reader i; The RFID reader is used to read the signal strength of u undetermined tags at the undetermined position, and the signal strength vector is obtained as follows: S=(S1,S2,...,S u ); In the formula, S i Indicates the value of the tag to be located on reader i.

3. The method according to claim 2, characterized in that The step of comparing the signal strength values ​​of the reference tag and the tag to be located to obtain a number of reference tags closest to the tag to be located specifically includes: According to the obtained signal strength vector of the reference tag and the signal strength vector of the tag to be located, the Euclidean distance between the two is calculated according to the following formula: Each label to be located gets a vector: E=(E1,E2,...,E n ); The smaller the E value is, the closer the distance between the reference tag and the tag to be located is, and then k reference tags with the closest signal strength to the tag to be located are obtained.

4. The method according to claim 3, characterized in that The method of estimating the coordinates of the tag to be located by using a weighted empirical formula based on the obtained reference tags closest to the tag to be located specifically includes: Based on the k reference tags that are closest to the tag to be located, the coordinates of the tag to be located are estimated using the weighted empirical formula as follows: where, W i is the weight of the i-th nearest neighbor reference label (i = 1, 2, 3, …, k, k < n, k is the k smallest neighbors among the n Euclidean distances E j ); (x i , y i ) is the position corresponding to the i-th reference label; among them, W i is obtained by using the following empirical formula:

5. The method according to claim 4, characterized in that The signal strength value is obtained by obtaining the signal strength values ​​within a period of time T, sorting the strength values, retaining the first k values ​​with the highest strength values, discarding the remaining (nk) values, and taking the average value as the final signal strength value, specifically including: Use the following formula to obtain the RSSI values ​​of the tags within the specified time T, sorted from large to small: R i =(R i1 ,R i2 ,...,R ik ,...,R id ); According to the obtained sorting intensity values, the average value of the intensity values ​​is obtained as the final signal intensity value according to the following formula: Where n is the total number of tags processed, and d is the number of signal strength values ​​read by the same tag within a specified time.

6. A logistics support positioning system based on RFID, characterized in that: The RFID-based logistics support positioning method according to any one of claims 1 to 5 is adopted, wherein the system comprises: The intensity value acquisition module is used to use a wireless radio frequency identification RFID reader to read the intensity values ​​of the reference tag at a fixed position and the to-be-determined tag signal at a to-be-determined position respectively; A comparison module, used to compare the signal strength values ​​of the reference tag and the tag to be determined, and obtain a number of reference tags closest to the tag to be determined; The coordinate acquisition module is used to estimate the coordinates of the tag to be located by using a weighted empirical formula based on a number of reference tags that are closest to the tag to be located.

7. The system according to claim 6, characterized in that The number of the RFID readers is m; the number of the reference tags is n; the number of the tags to be located is u; The intensity value acquisition module is specifically used for: The signal strength of n reference tags at fixed positions is read by an RFID reader, and the signal strength vector is as follows: θ=(θ1,θ2,...,θ n ); In the formula, θ i represents the value of the reference tag on reader i; The RFID reader is used to read the signal strength of u undetermined tags at the undetermined position, and the signal strength vector is obtained as follows: S=(S1,S2,...,S u ); In the formula, S i Indicates the value of the tag to be located on reader i.

8. The system according to claim 7, characterized in that The comparison module is specifically used for: According to the obtained signal strength vector of the reference tag and the signal strength vector of the tag to be located, the Euclidean distance between the two is calculated according to the following formula: Each label to be located gets a vector: E=(E1,E2,...,E n ); The smaller the E value is, the closer the distance between the reference tag and the tag to be located is, and then k reference tags with the closest signal strength to the tag to be located are obtained.

9. The system according to claim 8, characterized in that The coordinate acquisition module is specifically used for: Based on the k reference tags that are closest to the tag to be located, the coordinates of the tag to be located are estimated using the weighted empirical formula as follows: Where, W i is the weight of the i-th nearest neighbor reference label (i = 1, 2, 3, …, k, k < n, and k is the k smallest neighbors among the n Euclidean distances E j ); (x i , y i ) is the position corresponding to the i-th reference label; among them, W i is obtained by using the following empirical formula:

10. The system according to claim 9, characterized in that The signal strength value is obtained by obtaining the signal strength values ​​within a period of time T, sorting the strength values, retaining the first k values ​​with the highest strength values, discarding the remaining (nk) values, and taking the average value as the final signal strength value, specifically including: Use the following formula to obtain the RSSI values ​​of the tags within the specified time T, sorted from large to small: R i =(R i1 ,R i2 ,...,R ik ,...,R id ); According to the obtained sorting intensity values, the average value of the intensity values ​​is obtained as the final signal intensity value according to the following formula: Where n is the total number of tags processed, and d is the number of signal strength values ​​read by the same tag within a specified time.

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