A positioning method, system and intelligent clothing based on signal strength

Abstract

The present invention provides a positioning method based on signal strength, including: a processing device obtaining a target area where a positioning tag is located according to a plurality of signal strength value groups calculated by a plurality of positioning base stations respectively arranged in a plurality of positioning areas; the target area being one of the plurality of positioning areas; wherein each signal strength value group is obtained by a corresponding positioning base station through receiving a plurality of broadcast signals and calculating; the plurality of broadcast signals are obtained by the positioning tag transmitting at different transmission powers. In addition, a positioning system based on signal strength and intelligent clothing are also provided. By using a plurality of positioning base stations in a plurality of positioning areas and based on the RSSI positioning algorithm, area-level positioning is realized. In special scenarios such as nursing homes, room-level positioning of a target object can be accurately achieved, with extremely high reliability; in addition, by comprehensively judging using a plurality of broadcast signals with different powers, the error can be further reduced and the positioning accuracy can be improved.

Description

Technical Field

[0001] The present invention relates to the technical field of positioning, and particularly to a positioning method, system and intelligent clothing based on signal strength. Background Art

[0002] With the development of technology, positioning technology has become more and more mature, and personnel positioning and equipment positioning are widely realized in various industries. Currently, the more commonly used positioning technologies include RSSI (Received Signal Strength Indication) positioning technology and AOA (Angle of Arrival) positioning technology, and both of these two positioning technologies can achieve point positioning.

[0003] However, in the prior art, the application of positioning technology is relatively conventional and rigid, without differential design for specific scenarios, and still adopts the most basic application, resulting in very low positioning accuracy in some scenarios, especially difficult to apply in scenarios with complex spatial structures. Summary of the Invention

[0004] Aiming at the deficiencies in the prior art, the present invention provides a positioning method, system and intelligent clothing based on signal strength.

[0005] In a first aspect, in one embodiment, the present invention provides a positioning method based on signal strength, including:

[0006] A processing device obtains a target area where a positioning tag is located according to a plurality of signal strength value groups calculated by a plurality of positioning base stations respectively arranged in a plurality of positioning areas; the target area is one of the plurality of positioning areas;

[0007] Wherein, each signal strength value group is calculated by a corresponding positioning base station through receiving a plurality of broadcast signals; the plurality of broadcast signals are obtained by the positioning tag transmitting with different transmission powers.

[0008] In a second aspect, in one embodiment, the present invention provides a positioning system based on signal strength, including:

[0009] A processing device, configured to obtain a target area where a positioning tag is located according to a plurality of signal strength value groups calculated by a plurality of positioning base stations respectively arranged in a plurality of positioning areas; the target area is one of the plurality of positioning areas;

[0010] Wherein, each signal strength value group is calculated by a corresponding positioning base station through receiving a plurality of broadcast signals; the plurality of broadcast signals are obtained by the positioning tag transmitting with different transmission powers.

[0011] Thirdly, in one embodiment, the present invention provides an intelligent garment, which includes a body and a positioning tag integrated on the body. The intelligent garment uses the positioning method based on signal strength in the above embodiment to achieve the positioning of the target object.

[0012] Through the above positioning method, system and intelligent garment based on signal strength, multiple positioning base stations in multiple positioning areas are adopted, and based on the RSSI positioning algorithm, area-level positioning is achieved. In special scenarios such as nursing homes, room-level positioning of the target object can be accurately achieved, and the reliability is extremely high. In addition, by comprehensively judging multiple broadcast signals with different powers, the error can be further reduced and the positioning accuracy can be improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the following drawings are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0014] Among them:

[0015] Figure 1 is a schematic flowchart of the positioning method based on signal strength in one embodiment of the present invention;

[0016] Figure 2 is a schematic flowchart of the positioning method based on signal strength in another embodiment of the present invention;

[0017] Figure 3 is a schematic circuit structure diagram of the positioning system based on signal strength in one embodiment of the present invention;

[0018] Figure 4 is a schematic distribution diagram of the positioning base station in one embodiment of the present invention;

[0019] Figure 5 is a schematic flowchart of obtaining the target area through the positioning model in one embodiment of the present invention;

[0020] Figure 6 is a schematic flowchart of training the positioning model in one embodiment of the present invention;

[0021] Figure 7 is a schematic flowchart of the positioning tag transmitting a broadcast signal in one embodiment of the present invention;

[0022] Figure 8 is a schematic flowchart of the positioning tag adjusting the frequency of the broadcast signal in one embodiment of the present invention;

[0023] Figure 9 Schematic structural diagram of a positioning tag in an embodiment of the present invention;

[0024] Figure 10 Schematic structural diagram of a flexible middle frame and internal electronic modules in an embodiment of the present invention;

[0025] Figure 11 Schematic flow diagram of an AOA-based positioning method in an embodiment of the present invention;

[0026] Figure 12 Schematic structural diagram of the principle of an AOA positioning algorithm in an embodiment of the present invention;

[0027] Figure 13 Schematic flow diagram of calibrating initial positioning coordinates based on the moving distance in an embodiment of the present invention;

[0028] Figure 14 Schematic flow diagram of calibrating initial positioning coordinates based on the first angle in an embodiment of the present invention.

[0029] In the above-mentioned drawings: 11, flexible middle frame; 12, waterproof film; 131, battery; 132, circuit board. Specific embodiments

[0030] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0031] In order to make the objectives, technical solutions and advantages of the present invention clearer and more understandable, the present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0032] In a first aspect, as Figure 1 and Figure 3 shown, in an embodiment, the present invention provides a positioning method based on signal strength, including:

[0033] Step 102, the positioning tag emits multiple broadcast signals with different transmission powers.

[0034] Among them, a preset transmission power gradient is stored in the positioning tag, so that each time it is transmitted according to the preset transmission power gradient. The transmission power gradient includes a gradient range and the difference between adjacent powers.

[0035] Multiple positioning base stations respectively set in multiple positioning areas; for each positioning base station:

[0036] Step 104, the positioning base station receives multiple broadcast signals and calculates the signal strength values of the multiple broadcast signals when received, obtaining a signal strength value group.

[0037] Among them, the positioning base station analyzes the power value, timestamp, feature code, etc. carried in the received broadcast signal, and calculates the signal strength value of the broadcast signal.

[0038] Step 106, the processing device obtains the target area where the positioning tag is located according to the multiple signal strength value groups.

[0039] Among them, the processing device can judge whether the broadcast signals received by multiple positioning base stations are emitted at the same time and the same transmission power according to the parsed power value, timestamp and feature code. If they are broadcast signals with the same feature code emitted at the same time and the same transmission power, the target area of the positioning tag is judged by combining the different signal strength values calculated by multiple positioning base stations;

[0040] The target area is one of the multiple positioning areas. This embodiment is based on the RSSI (Received Signal Strength Indication) positioning algorithm, and uses the property that the signal strength will attenuate during the propagation of the broadcast signal, so as to judge which positioning base station the positioning tag is closer to, and the positioning area where the positioning base station is located is the target area where the positioning tag is located.

[0041] Positioning principle based on RSSI positioning algorithm:

[0042] d = 10 ((|rssi|-A) / (10·n)) (1)

[0043] In the formula, d is the distance between the positioning tag and the positioning base station; rssi is the signal strength value, which is negative; A is the absolute value of the rssi value when the distance from the positioning base station is 1m, which is determined by the transmission power of the positioning tag. The smaller the transmission power, the larger the value of A. The best range of A is between 45 and 49; n is the environmental attenuation factor, which needs to be tested and corrected. The best range of n is between 3.25 and 4.5.

[0044] |rssi| = 10·nlog(d) + A (2)

[0045] From formula (1), the relationship between the absolute value of the rssi value and the distance d and A is as shown in formula (2). It can be seen from formula (2) that by adjusting the transmission power of the positioning tag, the signal strength value |rssi| received by the positioning base station can be changed.

[0046] Such as Figure 4As shown, each box represents a positioning area, and the black dots in the boxes represent positioning base stations. Among them, for indoor positioning scenarios, when room-level positioning is required, each positioning area represents a room. Since the broadcast signal will cause a sharp attenuation in signal strength when passing through the wall, and the degree of attenuation is much higher than the distance attenuation without obstruction, the positioning base station can be set in any area within the room at this time, and there is no need to control the size of each room.

[0047] The transmission power can be adjusted through the positioning tag, and at the same time, the power value and characteristic parameters (such as timestamps, characteristic encodings, etc.) that can represent the broadcast packet sequence are carried in the broadcast signal. For the same broadcast packet, the room where the positioning base station with the strongest received signal strength is located is the room where the positioning tag is located. A calculation result can be obtained for each power corresponding to the broadcast signal. Therefore, multiple calculation results can be obtained from multiple broadcast signals with different powers, and then the attenuation properties of each power are synthesized to obtain an accurate positioning result.

[0048] In addition, it should be noted that when multiple positioning areas are all within the same room, there is no wall penetration attenuation at this time, and the attenuation is basically determined by the propagation distance. Therefore, it is necessary to control the size of each positioning area and the position of the positioning base station set in the positioning area.

[0049] Among them, the positioning tag and the positioning base station communicate using the Bluetooth communication protocol. Specifically, the Bluetooth 5.1 protocol is used. Using the Bluetooth communication protocol can reduce power consumption, and the communication distance of Bluetooth can also meet the usage requirements.

[0050] Through the above positioning method based on signal strength, multiple positioning base stations in multiple positioning areas are used, and based on the RSSI positioning algorithm, area-level positioning is achieved. In special scenarios such as nursing homes, room-level positioning of target objects can be accurately achieved with extremely high reliability; in addition, by comprehensively judging multiple broadcast signals with different powers, the error can be further reduced and the positioning accuracy can be improved.

[0051] Such as Figure 2 As shown, in one embodiment, the processing device obtains the target area where the positioning tag is located according to multiple signal strength value groups, including:

[0052] Step 206, the processing device inputs multiple signal strength value groups into the trained positioning model to obtain the target area where the positioning tag is located output by the positioning model.

[0053] Among them, as Figure 5 shown, rssi1MN represents the first positioning tag with transmission power P NWhen transmitting a broadcast signal, the signal strength value of the broadcast signal received by the Mth positioning base station. Rssi111 to rssi11N are the signal strength value groups of the first positioning base station, and rssi1M1 to rssi1MN are the signal strength value groups of the Mth positioning base station. Input all the signal strength value groups corresponding to the first positioning tag into the trained positioning model, and the positioning model can output the target area corresponding to the first positioning tag, such as outputting a room number.

[0054] Among them, through the training and learning of a large amount of data, the positioning model can automatically avoid some errors. Especially for room-level positioning, it can avoid the attenuation calculation error caused by passing through walls, thus greatly improving the positioning accuracy.

[0055] Such as Figure 6 As shown, in one embodiment, the training steps of the positioning model include:

[0056] Obtain a training sample set, where the training sample set includes multiple training samples, and each training sample includes multiple training signal strength value groups and a training target area respectively corresponding to multiple positioning base stations;

[0057] Obtain a training sample, such as rssi111 to rssi1MN, which includes M training signal strength value groups. Through manual annotation, obtain the training target area corresponding to the M training signal strength value groups. Use the multiple training signal strength value groups as the input of the positioning model, and use the training target area as the expected output of the positioning model to train the positioning model, that is, complete one training;

[0058] Determine the comparison result between the actual output and the expected output of the positioning model. If the comparison result does not meet the requirements, update the model parameters of the positioning model according to the comparison result;

[0059] Obtain the next training sample, such as rssi211 to rssi2MN, and then re-enter the step of using the multiple training signal strength value groups as the input of the positioning model and using the training target area as the expected output of the positioning model to train the positioning model until the obtained comparison result meets the requirements, and then stop training to obtain the trained positioning model.

[0060] In one embodiment, determine the comparison result between the actual output and the expected output of the positioning model. If the comparison result does not meet the requirements, update the model parameters of the positioning model according to the comparison result, including:

[0061] Determine the comparison difference between the actual output and the expected output of the positioning model, and calculate the loss value according to the comparison difference;

[0062] If the loss value does not meet the preset convergence condition, update the model parameters of the positioning model according to the loss value.

[0063] In one embodiment, after the positioning model is trained, the following steps are further included:

[0064] Obtain a test sample set, where the test sample set includes multiple test samples, and each test sample includes multiple groups of test signal strength values corresponding to multiple positioning base stations respectively;

[0065] Input each test sample into the trained positioning model in sequence for testing. The testing process is the same as the above actual usage process and will not be elaborated here;

[0066] If the testing effect is not good, the weight parameters of the positioning model need to be further adjusted.

[0067] In one embodiment, the positioning model includes algorithms such as decision tree, support vector machine, and deep learning.

[0068] In one embodiment, before the step in which the processing device obtains the target area where the positioning tag is located according to multiple groups of signal strength values, the following steps are further included:

[0069] For the positioning base station, calculate the signal strength value corresponding to the received broadcast signal; for the broadcast signal not received, use the preset strength value as the signal strength value corresponding to it, and obtain a group of signal strength values according to multiple signal strength values.

[0070] Among them, the above-mentioned positioning base station stores a preset transmission power gradient, so it can be judged which power's corresponding broadcast signal is successfully received and which power's corresponding broadcast signal is not successfully received. Since a group of signal strength values needs to be formed, for the broadcast signal that the positioning base station fails to receive, the preset strength value is used as the signal strength value of this broadcast signal. The preset strength value can be set to -200 or smaller, and the preset strength value indicates that this broadcast signal cannot be received.

[0071] As Figure 7 shown, in one embodiment, before the step in which the positioning base station calculates the signal strength value corresponding to the received broadcast signal; for the broadcast signal not received, uses the preset strength value as the signal strength value corresponding to it, and obtains a group of signal strength values according to multiple signal strength values, the following steps are further included:

[0072] The positioning tag transmits multiple broadcast signals at a preset switching period.

[0073] Among them, as mentioned above, the positioning tag transmits broadcast signals at a preset transmission power gradient, and the transmission time for different powers in the preset transmission power gradient needs to be set. Specifically, the transmission time of the broadcast signal corresponding to each power is set to the preset switching period.

[0074] For example, set the preset switching period to 1. When the positioning tag broadcasts according to the preset transmission power gradient, first select the transmission power P1, and then continuously judge whether the transmission time exceeds 1 s in real time. If not, continue to transmit at this transmission power. If so, switch to the transmission power P2 and repeat the judgment until all transmissions are completed.

[0075] Set the transmission time corresponding to each transmission power to a fixed value for the positioning base station to judge. For example, using the preset switching period in the above example, when the positioning base station does not receive the corresponding broadcast signal for 1 s continuously, it is determined that the reception is unsuccessful.

[0076] In one embodiment, the positioning tag emits signals in a cycle at a preset frequency. For example, if there are a total of 10 gradients in the preset transmission power gradient and the preset switching period is 1 s, it takes 10 s for the positioning tag to complete one transmission, and it takes about 10 s for the positioning base station to receive. The processing device takes a certain amount of time for calculation, such as 1 s for calculation, so it takes a total of 11 s to complete one positioning. At this time, the positioning period can be set to 20 s, and the corresponding preset frequency is 1 / 20 = 0.05 Hz. After the positioning tag completes a 10 s transmission task, it starts to standby. The positioning base station also stands by after completing a 10 s reception task until the positioning tag starts the next transmission task after 20 s. In this way, the transmission and reception times of the positioning tag and the positioning base station are synchronized, avoiding problems that cannot be calculated due to disorders.

[0077] As Figure 3 shown, in one embodiment, the above signal strength-based positioning method further includes:

[0078] The positioning tag adjusts the preset frequency according to the motion data output by the motion sensor integrated thereon.

[0079] Among them, the positioning tag emits signals in a cycle according to the preset frequency. The higher the preset frequency, the higher the required power consumption, and vice versa. Therefore, adjusting the preset frequency in combination with the motion data can greatly reduce the power consumption and improve the battery life of the positioning tag. It should be noted that when the positioning tag needs to emit a broadcast signal after adjusting the preset frequency, the adjusted preset frequency is packed into the broadcast signal, so that the positioning base station can obtain the adjusted preset frequency and achieve synchronization.

[0080] Among them, the motion sensor includes an acceleration sensor.

[0081] Among them, as Figure 8As shown, after the positioning tag starts the positioning broadcast, it first collects the acceleration of the current positioning tag through the acceleration sensor, and determines whether the acceleration is greater than threshold 1. Threshold 1 represents the demarcation point between the stationary state and the moving state. If the acceleration is not greater than threshold 1, it indicates that the positioning tag is basically in a stationary state at this time and does not need to be repositioned, so the broadcast is stopped. If the acceleration is greater than threshold 1, it indicates that the positioning tag is in a moving state at this time, and further determines whether the acceleration is greater than threshold 2. Threshold 2 represents the demarcation point between the normal moving state and the violent moving state. If the acceleration is not greater than threshold 2, it indicates that the positioning tag is in a normal moving state at this time and the displacement is small, so it broadcasts at a preset frequency f1 with a lower frequency. If the acceleration is greater than threshold 2, it indicates that the positioning tag is in a violent movement and the displacement is large, so it broadcasts at a preset frequency f2 with a higher frequency.

[0082] As Figure 3 shown, in one embodiment, each positioning area represents a room. Before the step of the processing device obtaining the target area where the positioning tag is located according to multiple signal strength value groups, it further includes;

[0083] A plurality of RFID card readers respectively arranged at the entrances of a plurality of rooms; for each RFID (Radio Frequency Identification) card reader:

[0084] The RFID card reader detects whether the RFID chip integrated on the positioning tag enters its own sensing range and generates detection data;

[0085] The processing device obtaining the target area where the positioning tag is located according to multiple signal strength value groups includes:

[0086] The processing device obtains the target area where the positioning tag is located output by the positioning model according to multiple signal strength value groups and multiple detection data.

[0087] Among them, for room-level positioning, the RFID chip and the RFID card reader can assist in confirming whether the positioning tag has left the room, improving the positioning accuracy. For example, the previous positioning shows that the positioning tag is in room A. When calculating the current positioning, the positioning tag is in room A or room B, and rooms A and B are adjacent. At this time, the RFID card reader in room A does not detect that the positioning tag has entered its own sensing range, indicating that the positioning tag has not gone out, so it is finally determined that the positioning tag is in room A.

[0088] In one embodiment, the sensing range of the RFID card reader can be set within 40 cm.

[0089] In one embodiment, the processing device obtains the target area where the positioning label output by the positioning model is located according to a plurality of signal strength value groups and a plurality of detection data, including:

[0090] The processing device inputs the plurality of signal strength value groups and the plurality of detection data into the trained positioning model to obtain the target area where the positioning label output by the positioning model is located.

[0091] As Figure 3 shown, in one embodiment, after the step in which the processing device obtains the target area where the positioning label is located according to a plurality of signal strength value groups, it further includes:

[0092] The processing device outputs the target area where the positioning label is located to the display device;

[0093] The display device is used to display the target area where the target object is located.

[0094] Visualization is achieved through the display device, which is convenient for management personnel to view and improves management efficiency.

[0095] In a second aspect, as Figure 3 shown, in one embodiment, the present invention provides a positioning system based on signal strength, including:

[0096] A positioning label for transmitting a plurality of broadcast signals with different transmission powers;

[0097] A plurality of positioning base stations respectively arranged in a plurality of positioning areas; for each positioning base station: for receiving a plurality of broadcast signals and calculating the signal strength values of the plurality of broadcast signals when received to obtain a signal strength value group;

[0098] A processing device for obtaining the target area where the positioning label is located according to a plurality of signal strength value groups; the target area is one of the plurality of positioning areas.

[0099] Through the above positioning system based on signal strength, a plurality of positioning base stations in a plurality of positioning areas are adopted, and regional-level positioning is realized based on the RSSI positioning algorithm. In special scenarios such as nursing homes, room-level positioning of target objects can be accurately achieved, and the reliability is extremely high; in addition, by comprehensively judging a plurality of broadcast signals with different powers, the error can be further reduced and the positioning accuracy can be improved.

[0100] In one embodiment, the processing device is specifically configured to input the plurality of signal strength value groups into the trained positioning model to obtain the target area where the positioning label output by the positioning model is located.

[0101] In one embodiment, the processing device is further configured to obtain a training sample set, where the training sample set includes a plurality of training samples, and each training sample includes a plurality of training signal strength value groups respectively corresponding to a plurality of positioning base stations and a training target area;

[0102] Obtain a training sample, use the plurality of training signal strength value groups as the input of the positioning model, use the training target area as the expected output of the positioning model, and train the positioning model;

[0103] Determine the comparison result between the actual output and the expected output of the positioning model. If the comparison result does not meet the requirements, update the model parameters of the positioning model according to the comparison result;

[0104] Obtain the next training sample, and re-enter the step of using the plurality of training signal strength value groups as the input of the positioning model, using the training target area as the expected output of the positioning model, and training the positioning model, until the obtained comparison result meets the requirements, then stop training to obtain the trained positioning model.

[0105] In one embodiment, determining the comparison result between the actual output and the expected output of the positioning model. If the comparison result does not meet the requirements, updating the model parameters of the positioning model according to the comparison result includes:

[0106] Determine the comparison difference between the actual output and the expected output of the positioning model, and calculate a loss value according to the comparison difference;

[0107] If the loss value does not meet the preset convergence condition, update the model parameters of the positioning model according to the loss value.

[0108] In one embodiment, the positioning base station is specifically configured to calculate the signal strength value corresponding to the received broadcast signal; for the broadcast signal not received, use the preset strength value as the signal strength value corresponding to it, and obtain a signal strength value group according to the plurality of signal strength values.

[0109] In one embodiment, the positioning tag is specifically configured to transmit a plurality of broadcast signals at a preset switching period.

[0110] In one embodiment, one of the positioning base stations is used as the master base station and is connected to other positioning base stations; the processing device is integrated on the master base station.

[0111] Wherein, the master base station is connected to other positioning base stations by wired (serial port, I2C, etc.), wireless (Bluetooth, etc.) means.

[0112] In other embodiments, the processing device can be an independent device, such as a server; all positioning base stations are directly connected to the processing device.

[0113] In one embodiment, the above signal strength-based positioning system further includes:

[0114] A motion sensor integrated on the positioning tag;

[0115] The positioning tag and the positioning base station respectively perform signal transmission and signal reception in a cyclic manner at a preset frequency; the positioning tag is further configured to adjust the preset frequency according to the motion data output by the motion sensor.

[0116] In one embodiment, each positioning area represents a room, and the above signal strength-based positioning system further includes:

[0117] An RFID chip integrated on the positioning tag;

[0118] A plurality of RFID readers respectively arranged at the doorways of a plurality of rooms; for each RFID reader: configured to detect whether the RFID chip enters the sensing range and generate detection data;

[0119] The processing device is specifically configured to obtain the target area where the positioning tag is located output by the positioning model according to a plurality of signal strength value groups and a plurality of detection data.

[0120] In one embodiment, the processing device is specifically configured to input a plurality of signal strength value groups and a plurality of detection data into a trained positioning model to obtain the current area where the positioning tag is located output by the positioning model when the positioning tag is located.

[0121] In one embodiment, the above signal strength-based positioning system further includes:

[0122] A display device connected to the processing device; <s

[0123] The processing device is configured to output the target area where the positioning tag is located to the display device;

[0124] The display device is configured to display the target area where the target object is located.

[0125] In one embodiment, each positioning area represents a room, and it further includes:

[0126] Shielding layers respectively arranged on the inner walls of a plurality of rooms.

[0127] Wherein, the shielding layer can block the propagation of broadcast signals. When applied to room-level positioning, it is difficult for the positioning base station in any one room to receive the broadcast signals emitted by the positioning tags in other rooms, thereby eliminating some interference and improving the positioning accuracy. In addition, it can also prevent the problem of data eavesdropping.

[0128] In one embodiment, the shielding layer can be obtained by coating a conductive coating on the wall.

[0129] In one embodiment, the shielding layer includes a steel mesh or an iron sheet.

[0130] In one embodiment, the shielding layer can be disposed on the surface of the wall or inside the wall.

[0131] In a third aspect, in one embodiment, the present invention provides an intelligent garment, including a body and a positioning tag integrated on the body. The intelligent garment uses the positioning method based on signal strength in any of the above embodiments to implement the positioning of the target object.

[0132] Through the above intelligent garment, multiple positioning base stations in multiple positioning areas are adopted, and based on the RSSI positioning algorithm, area-level positioning is achieved. In special scenarios such as nursing homes, room-level positioning of the target object can be accurately achieved, and the reliability is extremely high; in addition, by comprehensively judging multiple broadcast signals with different powers, the error can be further reduced and the positioning accuracy can be improved.

[0133] As Figure 9 and Figure 10 shown, in one embodiment, the positioning tag includes:

[0134] A flexible middle frame 11;

[0135] An electronic module disposed within the flexible middle frame 11;

[0136] The electronic module includes a battery 131 and a circuit board 132; the circuit board 132 is integrated with a processing module, a broadcast module, an RFID chip, and a motion sensor;

[0137] A waterproof film 12 disposed on at least one side of the flexible middle frame 11.

[0138] Among them, the electronic module is a flexible electronic module obtained by a flexible packaging technology.

[0139] Among them, the flexible middle frame 11 is made of EVA (ethylene-vinyl acetate copolymer) material and has a waterproof function itself.

[0140] Among them, since the electronic module needs to be disposed inside the flexible middle frame 11, at least one side of the flexible middle frame 11 needs to be provided with a groove for placing the electronic module. After the electronic module is placed, this side is not sealed, so a waterproof film 12 needs to be added for sealing.

[0141] Among them, the waterproof film 12 is made of (Polyethylene) material.

[0142] Among them, the positioning tag can be sewn on the garment, specifically in the interlayer of the fabric, so as to obtain an intelligent garment with a positioning function.

[0143] By flexibly and waterproofly designing the positioning tag, it can be sewn on the clothing, avoiding local skin ulcers or discomfort caused by the wearing method.

[0144] In one embodiment, the flexible middle frame and the waterproof membrane can be made of the same material.

[0145] Fourthly, as Figure 3 and Figure 11 shown, in one embodiment, the present invention provides an AOA-based positioning method, including:

[0146] Step 302, the processing device obtains the initial positioning coordinates where the positioning tag is located according to the angles of arrival respectively calculated by multiple positioning base stations.

[0147] Among them, the positioning principle of the AOA positioning algorithm: as Figure 12 shown, O1 and O2 respectively represent the first coordinate and the second coordinate corresponding to two positioning base stations. The two positioning base stations respectively perform the AOA algorithm to obtain the first angle of arrival α of the broadcast signal to the first coordinate and the second angle of arrival β of the broadcast signal to the second coordinate. The processing device performs a fusion algorithm: obtaining the first ray according to the first coordinate O1 and the first angle of arrival α, and obtaining the second ray according to the second coordinate O2 and the second angle of arrival β. When performing planar positioning, the first ray and the second ray are basically in the same plane, and the first ray and the second ray will intersect at a point, that is, the initial positioning coordinate A.

[0148] Step 304, the processing device calibrates the initial positioning coordinates according to the motion data between the positioning tag and the reference coordinates to obtain the target positioning coordinates where the positioning tag is located.

[0149] Among them, the motion data is calculated by the motion sensor.

[0150] Among them, the reference coordinate can be the target positioning coordinate obtained from the previous positioning.

[0151] Through the above AOA-based positioning method, the AOA positioning algorithm with higher positioning accuracy is adopted, and the motion data output by the motion sensor is also used to calibrate the initial positioning coordinates obtained by the AOA algorithm, so as to obtain higher-precision target positioning coordinates, enabling it to be applied to positioning scenarios with relatively complex spatial structures.

[0152] In one embodiment, the processing device calibrates the initial positioning coordinates according to the motion data between the positioning tag and the reference coordinates, including:

[0153] The processing device calibrates the initial positioning coordinates according to the first moving distance between the positioning tag and the reference coordinates; the first moving distance is calculated by the motion sensor.

[0154] Among them, after obtaining the initial positioning coordinates, the distance from the reference coordinates can be calculated, and then calibrated by the first moving distance obtained by the motion sensor, thereby eliminating some interference and improving the positioning accuracy.

[0155] In one embodiment, the processing device calibrates the initial positioning coordinates according to the first moving distance between the positioning tag and the reference coordinates, including:

[0156] The processing device calibrates the initial positioning coordinates according to the first moving distance and the second moving distance between the positioning tag and the reference coordinates; the reference coordinates are the coordinates corresponding to the reference base station, and the reference base station is one of the multiple positioning base stations, and the second moving distance is calculated from the signal strength value corresponding to the broadcast signal received by the reference base station.

[0157] Among them, the positioning principle of the RSSI positioning algorithm:

[0158] d = 10 ((|rssi|-A) / (10·n)) (1)

[0159] In the formula, d is the distance between the positioning tag and the positioning base station; rssi is the signal strength value, which is negative; A is the absolute value of the rssi value when the distance from the positioning base station is 1m, which is determined by the transmission power of the positioning tag. The smaller the transmission power, the larger the value of A. The best range of A is between 45 and 49; n is the environmental attenuation factor, which needs to be tested and corrected. The best range of n is between 3.25 and 4.5. Therefore, the second moving distance between the positioning tag and the reference coordinates can be obtained by calculating the signal strength value corresponding to the received broadcast signal.

[0160] Among them, taking the coordinates corresponding to the reference base station as the reference coordinates is to facilitate obtaining the second moving distance; if the target positioning coordinates obtained from the previous positioning are still used as the reference coordinates, since the positioning base station can only directly calculate the distance from the signal strength value to the positioning tag, and this distance is different from the second moving distance between the positioning tag and the reference coordinates, it is necessary to further calculate the positioning coordinates obtained based on RSSI, and then calculate the second moving distance, thus increasing the system redundancy.

[0161] Calibration is performed through the third moving distance to further eliminate errors and improve the positioning accuracy.

[0162] As Figure 13 shown, in one embodiment, the processing device calibrates the initial positioning coordinates according to the first moving distance and the second moving distance between the positioning tag and the reference coordinates to obtain the target positioning coordinates where the positioning tag is located, including:

[0163] Step 402: The processing device obtains a third moving distance between the positioning tag and the reference coordinate according to the initial positioning coordinate.

[0164] Among them, if the reference coordinate is (x0, y0) and the initial positioning coordinate is (x1, y1), then the third moving distance L0 is:

[0165]

[0166] Step 404: The processing device obtains a target moving distance according to the first moving distance, the second moving distance, and the third moving distance.

[0167] Among them, the target moving distance can be obtained by simple averaging or weighted averaging of the first moving distance, the second moving distance, and the third moving distance.

[0168] Step 406: The processing device calibrates the initial positioning coordinate according to the target moving distance to obtain a target positioning coordinate.

[0169] Among them, if the obtained target moving distance is L1 and the target positioning coordinate is (x, y), then:

[0170]

[0171] Among them, this embodiment mainly calibrates the initial positioning coordinate starting from the distance.

[0172] In one embodiment, the processing device obtains a target moving distance according to the first moving distance, the second moving distance, and the third moving distance, including:

[0173] The processing device performs weighted averaging on the first moving distance, the second moving distance, and the third moving distance according to preset weight parameters to obtain the target moving distance.

[0174] Among them, if the first moving distance is L a , the second moving distance is L r , the third moving distance is L0, the weight corresponding to the first moving distance is P a , the weight corresponding to the second moving distance is P r , and the weight corresponding to the third moving distance is P0, then the target moving distance L1 is:

[0175]

[0176] Among them, the weight of each moving distance needs to be determined according to the application scenario, and the weight of the moving distance corresponding to the positioning method with higher positioning accuracy in the scenario is set to be higher.

[0177] In one embodiment, the processing device calibrates the initial positioning coordinates according to the motion data between the positioning tag and the reference coordinates, including:

[0178] The processing device calibrates the initial positioning coordinates according to the first angle between the positioning tag and the reference coordinates; the first angle is calculated by the motion sensor.

[0179] Among them, when the initial positioning coordinates are obtained, the angle between the positioning tag and the reference coordinates can be calculated, and then calibrated by the first angle obtained by the motion sensor, thereby eliminating some interference and improving the positioning accuracy.

[0180] Such as Figure  14 As shown, in one embodiment, the processing device calibrates the initial positioning coordinates according to the motion data between the positioning tag and the reference coordinates to obtain the target positioning coordinates where the positioning tag is located, including:

[0181] Step 502, the processing device obtains the third moving distance between the positioning tag and the reference coordinates according to the initial positioning coordinates.

[0182] Among them, the third moving distance is L0, and the calculation method of the third moving distance is the same as that in the above embodiment, and will not be elaborated here.

[0183] Step 504, the processing device obtains the target positioning coordinates where the positioning tag is located according to the reference coordinates, the third moving distance, and the first angle.

[0184] Among them, if the reference coordinate is (x0, y0), the target positioning coordinate is (x, y), and the first angle is θ, then:

[0185]

[0186] Among them, this embodiment mainly calibrates the initial positioning coordinates from the angle.

[0187] In one embodiment, the distance calibration and the angle calibration can be alternately executed. For example, first obtain a target positioning coordinate of the first calibration through the distance calibration, and then perform the angle calibration on the target positioning coordinate of the first calibration to obtain a target positioning coordinate of the second calibration, so that the positioning accuracy is higher. Of course, the angle calibration can also be performed first and then the distance calibration.

[0188] In one embodiment, the positioning tag and the positioning base station respectively perform signal transmission and signal reception in a preset frequency cycle.

[0189] For example, it takes 1 s for a positioning tag to complete one signal transmission. The positioning base station needs to synchronously receive the 1-s broadcast signal, and the processing device needs a certain amount of time for calculation, such as 1 s. Therefore, it takes a total of 2 s to complete one positioning. At this time, the positioning period can be set to 10 s, and the corresponding preset frequency is 1 / 10 = 0.1 Hz. After completing a 1-s transmission task, the positioning tag starts to standby. The positioning base station also stands by after synchronously completing the reception task until the positioning tag starts the next transmission task after 10 s. In this way, the transmission and reception times of the positioning tag and the positioning base station are kept synchronized, avoiding problems such as disorder that may lead to inability to calculate.

[0190] As Figure 3 shown, in one embodiment, the above AOA-based positioning method further includes:

[0191] The positioning tag adjusts the preset frequency according to the motion data.

[0192] Among them, the positioning tag transmits cyclically according to the preset frequency. The higher the preset frequency, the higher the required power consumption, and vice versa. Therefore, adjusting the preset frequency in combination with the motion data can greatly reduce the power consumption and improve the battery life of the positioning tag. It should be noted that when the positioning tag needs to re-transmit the broadcast signal after adjusting the preset frequency, the adjusted preset frequency is packed into the broadcast signal, so that the positioning base station can obtain the adjusted preset frequency to achieve synchronization.

[0193] Among them, the motion sensor includes an acceleration sensor.

[0194] Among them, as Figure 8 shown, after the positioning tag starts the positioning broadcast, it first collects the acceleration of the current positioning tag through the acceleration sensor, and determines whether the acceleration is greater than threshold 1. Threshold 1 represents the demarcation point between the stationary state and the moving state; if the acceleration is not greater than threshold 1, it means that the positioning tag is basically in a stationary state at this time and does not need re-positioning, so the broadcast is stopped; if the acceleration is greater than threshold 1, it means that the positioning tag is in a moving state at this time, and further determines whether the acceleration is greater than threshold 2. Threshold 2 represents the demarcation point between the normal motion state and the violent motion state; if the acceleration is not greater than threshold 2, it means that the positioning tag is in a normal motion state at this time and the displacement is small, so it broadcasts at a relatively low preset frequency f1; if the acceleration is greater than threshold 2, it means that the positioning tag is in a violent motion and the displacement is large, so it broadcasts at a relatively high preset frequency f2.

[0195] As Figure 3 shown, in one embodiment, the method is applied to indoor positioning; the processing device calibrates the initial positioning coordinates according to the motion data between the positioning tag and the reference coordinates, including:

[0196] The processing device calibrates the initial positioning coordinates according to the motion data and the detection data; the detection data is generated by an RFID (Radio Frequency Identification) card reader set at the door of the room by detecting whether the RFID chip enters the corresponding sensing range.

[0197] Among them, for indoor positioning, the RFID chip and the RFID card reader can assist in confirming whether the positioning tag has left the room, improving the positioning accuracy. For example, the previously calculated target positioning coordinates indicate that the positioning tag is at a certain coordinate inside Room A, while the currently calculated target positioning coordinates indicate that the positioning tag is at the wall where Room A and Room B intersect. At this time, the RFID card reader in Room A does not detect the positioning tag entering its own sensing range, indicating that the positioning tag has not gone out. Therefore, it is finally determined that the positioning tag is inside Room A and at a certain coordinate inside the wall intersecting with Room B.

[0198] In one embodiment, the sensing range of the RFID card reader can be set within 40 cm.

[0199] In the fifth aspect, as Figure 3 shown, in one embodiment, the present invention provides a positioning system based on AOA, including:

[0200] A processing device, configured to obtain the initial positioning coordinates where the positioning tag is located according to the angles of arrival respectively calculated by multiple positioning base stations; calibrate the initial positioning coordinates according to the motion data between the positioning tag and the reference coordinates to obtain the target positioning coordinates where the positioning tag is located; the motion data is calculated by a motion sensor.

[0201] Through the above positioning system based on AOA, the AOA positioning algorithm with higher positioning accuracy is adopted, and the motion data output by the motion sensor is also used to calibrate the initial positioning coordinates obtained by the AOA algorithm, so as to obtain higher-precision target positioning coordinates, enabling it to be applied to positioning scenarios with a more complex spatial structure.

[0202] As Figure 3 shown, in one embodiment, the above positioning system based on AOA further includes:

[0203] A motion sensor, configured to calculate the motion data.

[0204] In one embodiment, the motion sensor is specifically configured to calculate the first moving distance between the positioning tag and the reference coordinates; the processing device is specifically configured to calibrate the initial positioning coordinates according to the first moving distance between the positioning tag and the reference coordinates.

[0205] In one embodiment, the processing device is specifically configured to calibrate the initial positioning coordinates according to a first moving distance and a second moving distance between the positioning tag and the reference coordinates; the reference coordinates are the coordinates corresponding to the reference base station, the reference base station is one of the multiple positioning base stations, and the second moving distance is calculated from the signal strength value corresponding to the broadcast signal received by the reference base station.

[0206] In one embodiment, the processing device is specifically configured to obtain a third moving distance between the positioning tag and the reference coordinates according to the initial positioning coordinates; obtain a target moving distance according to the first moving distance, the second moving distance, and the third moving distance; and calibrate the initial positioning coordinates according to the target moving distance to obtain the target positioning coordinates.

[0207] In one embodiment, the processing device is specifically configured to perform weighted averaging on the first moving distance, the second moving distance, and the third moving distance according to preset weight parameters to obtain the target moving distance.

[0208] In one embodiment, the motion sensor is specifically configured to calculate a first angle between the positioning tag and the reference coordinates; the processing device is specifically configured to calibrate the initial positioning coordinates according to the first angle between the positioning tag and the reference coordinates.

[0209] In one embodiment, the processing device is specifically configured to obtain a third moving distance between the positioning tag and the reference coordinates according to the initial positioning coordinates; and obtain the target positioning coordinates where the positioning tag is located according to the reference coordinates, the third moving distance, and the first angle.

[0210] In one embodiment, the motion sensor includes an acceleration sensor or a gyroscope.

[0211] Among them, the acceleration sensor can perform three-axis operations and can obtain relatively rough calculation results. The gyroscope can perform operations with six or more axes and can obtain relatively accurate calculation results.

[0212] As Figure 3 shown, in one embodiment, the above AOA-based positioning system further includes:

[0213] A positioning tag and multiple positioning base stations;

[0214] The positioning tag is configured to cyclically transmit signals at a preset frequency;

[0215] The positioning tag is further configured to adjust the preset frequency according to the motion data.

[0216] In one embodiment, the motion sensor is integrated on the positioning tag.

[0217] In one embodiment, the motion sensor is not integrated on the positioning tag, but is arranged on the clothing of the target object together with the positioning tag.

[0218] In one embodiment, one of the positioning base stations is connected to other positioning base stations as the master base station; the processing device is integrated on the master base station.

[0219] Among them, the master base station is connected to other positioning base stations by wired (serial port, I2C, etc.) or wireless (Bluetooth, etc.) means.

[0220] In other embodiments, the processing device can be an independent device, such as a server; all positioning base stations are directly connected to the processing device.

[0221] As Figure 3 shown, in one embodiment, the system is applied to indoor positioning; the above-mentioned AOA-based positioning system further includes:

[0222] RFID chip;

[0223] An RFID reader set at the room door for detecting whether the RFID chip enters the sensing range and generating detection data;

[0224] The processing device is specifically configured to calibrate the initial positioning coordinates according to the motion data and the detection data.

[0225] As Figure 3 shown, in one embodiment, the above-mentioned AOA-based positioning system further includes:

[0226] A display device connected to the processing device;

[0227] The processing device is used to output the target area where the positioning tag is located to the display device;

[0228] The display device is used to display the target area where the target object is located.

[0229] The technical features of the above embodiments can be combined arbitrarily. For the sake of brevity of description, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered as the scope recorded in this specification.

[0230] The above-described embodiments only represent several implementation manners of the present invention. Their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present invention, several modifications and improvements can still be made, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the present invention should be subject to the appended claims.

Claims

1. A positioning method based on signal strength, characterized in that Including: The processing device obtains the target area where the positioning tag is located based on multiple groups of signal strength values calculated by multiple positioning base stations respectively set in multiple positioning areas; The target area is one of the multiple positioning areas; Wherein, each group of signal strength values is calculated by the corresponding positioning base station through receiving multiple broadcast signals; the multiple broadcast signals are obtained by the positioning tag transmitting at different transmission powers; Each positioning area represents a room, multiple RFID readers are arranged at the entrances of multiple rooms, and an RFID chip is integrated on the positioning tag; Wherein, for room-level positioning, it can be confirmed whether the positioning tag has left the room through the RFID chip and the RFID reader, including: the previous positioning shows that the positioning tag is in Room A, and during the current positioning calculation, the positioning tag is in Room A or Room B. At this time, the RFID reader in Room A does not detect the positioning tag entering its sensing range, and it is determined that the positioning tag is in Room A.

2. The positioning method based on signal strength according to claim 1, wherein, The processing device obtains the target area where the positioning tag is located based on multiple groups of signal strength values calculated by multiple positioning base stations respectively set in multiple positioning areas, including: The positioning base station obtains the power value, timestamp and feature code of the multiple broadcast signals, and the processing device determines the target area of the positioning tag according to different signal strength values corresponding to the same broadcast signal received by multiple positioning base stations. Wherein, the same broadcast signal is a signal containing the same feature code transmitted by the positioning tag at the same moment and at the same transmission power.

3. The positioning method based on signal strength according to claim 1, wherein The processing device obtains the target area where the positioning tag is located based on multiple groups of signal strength values calculated by multiple positioning base stations respectively set in multiple positioning areas, including: The processing device inputs the multiple groups of signal strength values into the positioning model to obtain the target area where the positioning tag is located output by the positioning model.

4. The positioning method based on signal strength according to claim 1, characterized in that, Before the step that the processing device obtains the target area where the positioning tag is located based on multiple groups of signal strength values calculated by multiple positioning base stations respectively set in multiple positioning areas, it further includes: For the received broadcast signal, the positioning base station calculates the corresponding signal strength value; for the broadcast signal that is not received, the preset strength value is used as the corresponding signal strength value, and the signal strength value group is obtained according to the multiple signal strength values.

5. The positioning method based on signal strength according to claim 4, wherein Before the step that the positioning base station calculates the corresponding signal strength value for the received broadcast signal, and uses the preset strength value as the corresponding signal strength value for the broadcast signal that is not received, and obtains the signal strength value group according to the multiple signal strength values, it further includes: The positioning tag transmits multiple broadcast signals at a preset switching period.

6. The positioning method based on signal strength according to claim 5, characterized in that, Also including: The positioning tag adjusts the preset frequency of the broadcast signal transmission according to the motion data output by the motion sensor integrated thereon.

7. The positioning method based on signal strength according to claim 1, wherein The processing device obtains the target area where the positioning tag is located based on multiple groups of signal strength values calculated by multiple positioning base stations respectively set in multiple positioning areas, including: The processing device obtains the target area where the positioning tag is located according to the multiple groups of signal strength values and multiple pieces of detection data; Wherein, each of the positioning areas represents a room, and the multiple pieces of detection data are generated by multiple RFID readers respectively arranged at the doorways of multiple rooms by detecting whether the RFID chip integrated on the positioning tag enters the corresponding sensing range.

8. A positioning system based on signal strength, characterized in that Including: A processing device, configured to obtain the target area where the positioning tag is located according to multiple groups of signal strength values calculated by multiple positioning base stations respectively arranged in multiple positioning areas; The target area is one of the multiple positioning areas; Wherein, each group of signal strength values is calculated by the corresponding positioning base station by receiving multiple broadcast signals; the multiple broadcast signals are transmitted by the positioning tag with different transmission powers; Each of the positioning areas represents a room, multiple RFID readers are arranged at the doorways of multiple rooms, and an RFID chip is integrated on the positioning tag; Wherein, for room-level positioning, it can be confirmed whether the positioning tag has left the room through the RFID chip and the RFID reader, including: the previous positioning shows that the positioning tag is in room A, and during the current positioning calculation, the positioning tag is in room A or room B. At this time, the RFID reader in room A does not detect that the positioning tag enters its own sensing range, and it is determined that the positioning tag is in room A.

9. The positioning system based on signal strength according to claim 8, wherein The processing device is specifically configured to input the multiple groups of signal strength values into a positioning model to obtain the target area where the positioning tag is located output by the positioning model.

10. The positioning system based on signal strength according to claim 8, wherein Further including: The positioning tag is configured to transmit multiple broadcast signals with different transmission powers; Multiple positioning base stations respectively arranged in multiple positioning areas; For each positioning base station: configured to receive the multiple broadcast signals and calculate the signal strength values of the multiple broadcast signals when received to obtain a group of signal strength values.

11. The positioning system based on signal strength according to claim 10, characterized in that, One of the positioning base stations is used as a main base station and is connected to the other positioning base stations; the processing device is integrated on the main base station.

12. The positioning system based on signal strength according to claim 10, wherein Further including: A motion sensor integrated on the positioning tag; The positioning tag performs signal transmission in a preset frequency cycle; the positioning tag is further configured to adjust the preset frequency according to the motion data output by the motion sensor.

13. The positioning system based on signal strength according to claim 10, characterized in that, Each of the positioning areas represents a room, and further including: An RFID chip integrated on the positioning tag; Multiple RFID readers respectively arranged at the doorways of multiple rooms; for each RFID reader: configured to detect whether the RFID chip enters the sensing range and generate detection data; The processing device is specifically configured to obtain the target area where the positioning tag is located output by the positioning model according to the multiple groups of signal strength values and the multiple pieces of detection data.

14. The positioning system based on signal strength according to claim 8, wherein Each of the positioning areas represents a room, and further including: Shielding layers respectively arranged in multiple rooms.

15. An intelligent garment, characterized in that, It includes a body and a positioning tag integrated on the body, and the intelligent clothing uses the signal strength-based positioning method according to any one of claims 1-7 to implement the positioning of a target object.

16. The intelligent clothing according to claim 15, wherein The positioning tag includes: A flexible middle frame; An electronic module disposed within the flexible middle frame; A waterproof film disposed on at least one side of the flexible middle frame.

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