Management node, communication terminal, and data collection method

Abstract

The purpose of the present invention is to provide a data collection system management node, communication terminal, and terminal position ascertainment method that are capable of improving reliability of IoT data while keeping the construction, operation, and management of devices constituting an IoT service simple with minimal human intervention.　A data collection system 302 according to the present invention comprises a management node 13 and a plurality of communication terminals 14, and is characterized in that: the communication terminals 14 each transmit / receive radio waves to / from each other at an arbitrary timing and report the strengths of the received radio waves to the management node 13; and the management node 13 calculates the relative positions of the communication terminals 14 on the basis of the reported strengths.

Description

Technical Field

[0001] This disclosure relates to sensing data collection in the Internet of Things (IoT).

Background Art

[0002] Using a lightweight communication protocol that is standardized and does not require high performance, obtain the network configuration information and device information of terminals and devices. For example, in Non-Patent Document 1, a method using LLDP (Link Layer Discovery Protocol, see Non-Patent Document 3 for example) has been reported.

[0003] In the IoT, it is necessary to network-connect a large number of sensor terminals and collect the data (sensing data) they generate. Also, in data utilization in the IoT, not only the sensing data itself generated by sensor terminals, but also the importance of data related to sensing data, called metadata, has been reported (such as Non-Patent Document 2). It is expected that by obtaining and distributing sensing data and metadata together, users can safely and easily utilize the sensing data. For example, by using LLDP disclosed in Non-Patent Document 1, metadata (device information) such as the manufacturer name and model number related to sensing data can be collected with an economical system configuration.

Prior Art Documents

Non-Patent Documents

[0004]

Non-Patent Document 1

Non-Patent Document 2

[0005] As the proliferation of services utilizing IoT sensors (sensing devices) is expected to increase, it is conceivable that sensors may unintentionally enter a state different from the administrator's intentions (for example, location, environment, installation orientation, fixing status, power supply amount, etc.) when managing these services. In such a state, accurate data cannot be obtained from the sensor, potentially leading to incorrect control and the inability to provide appropriate services. To avoid this situation, it is necessary to periodically check the status of the sensors, but there is a challenge in that it is difficult for workers to inspect a large number of sensors. Furthermore, although it is possible to determine the location of sensors using BLE beacons, this requires deploying a large number of BLE beacons in precise locations, and there are challenges in that it is difficult for workers to perform this task accurately and to check for any deviations in the position of the BLE beacons.

[0006] Therefore, the present invention aims to provide a management node for a data collection system, a communication terminal, and a terminal location determination method that can improve the reliability of IoT data while keeping the construction, operation, and management of the group of devices constituting an IoT service as simple as possible with minimal human intervention, in order to solve the above problems. [Means for solving the problem]

[0007] To solve the above problems, the data collection system according to the present invention actively changes the settings of sensing devices, access points, beacons, and other communication terminals to measure relative positions and distances, thereby improving the accuracy of position determination on a floor map.

[0008] Specifically, the present invention relates to a management node of a data collection system comprising multiple communication terminals, The aforementioned communication terminal includes a data communication receiving unit that transmits and receives radio waves from each other at arbitrary timings and notifies the measured received strength of the radio waves, An information processing unit that calculates the relative position of the communication terminal from the notified received signal strength, It is characterized by being equipped with [the following features].

[0009] Furthermore, the present invention relates to a communication terminal that communicates with a management node of a data collection system, A data communication receiving unit that receives instruction signals from the management node, A beacon signal transmitting unit that transmits radio waves based on the instruction signal, A beacon signal receiving unit that receives radio waves from other communication terminals, A processing unit for measuring the received signal strength of the aforementioned radio waves, A data communication transmission unit that notifies the management node of the received signal strength, It is characterized by being equipped with [the following features].

[0010] Furthermore, the terminal location determination method according to the present invention is The ability to send and receive radio waves between multiple communication terminals at any given time. The communication terminal notifies the management node of the received signal strength of the radio waves it has received, and The management node calculates the relative position of the communication terminal from the received signal strength that has been notified. To do so.

[0011] In the space to be managed, any number of communication terminals (sensing devices, access points, or beacons) capable of sending and receiving radio waves to and from each other and measuring the strength of the received radio waves are placed. The relative positions of the communication terminals are then recorded at any time. By placing such communication terminals, the administrator can determine the location of the communication terminals themselves even if they move, and based on the location of the communication terminals, the administrator can also determine the locations of sensing devices, access points, and beacons within that space. In other words, the administrator can determine the current location and positional deviation of sensing devices without having to go to the space or manage a large number of BLE beacons.

[0012] Accordingly, the present invention provides a management node for a data collection system, a communication terminal, and a terminal location determination method that can improve the reliability of IoT data while keeping the construction, operation, and management of the group of devices constituting an IoT service as simple as possible with minimal human intervention.

[0013] It is preferable that the management node repeatedly calculates the relative position by varying the transmission intensity of the radio waves transmitted by the communication terminal. The distance d between communication terminals is calculated based on the received signal strength index (RSSI), but the accuracy of the distance d can be improved by changing the transmitted radio wave strength.

[0014] It is preferable that the communication terminal notifies the received signal strength using an extended area of ​​the Layer 2 communication protocol. By using a Layer 2 communication protocol, it is unnecessary to establish a connection between the communication terminal and the management node, allowing for low-load and high-speed determination of the relative location of the communication terminal.

[0015] Furthermore, the management node, Obtaining the positional relationship between the sensing terminal that acquires sensing data and the communication terminal, and Regarding the information on the sensing terminal obtained from the positional relationship as metadata, and storing the sensing data and the metadata by associating them with each other is further performed.

[0016] Grasp the positions of each sensing device from the relative position of the communication terminal, and manage the position information in association with the sensing data acquired by each sensing device as metadata. Even if the position of the sensing device is deviated, the administrator can recognize that it is the sensing data at the deviated position, and it can also be used for services as the sensing data at the deviated position.

[0017] In addition, the above inventions can be combined as much as possible.

Effect of the Invention

[0018] The present invention can provide a management node, a communication terminal, and a terminal position grasping method of a data collection system that can enhance the reliability of IoT data while keeping the construction, operation, and management of a group of devices constituting an IoT service as simple as possible without much manual intervention. In addition, the present invention eliminates the need for pre-accurately deploying a large number of BLE beacons, etc., and introducing an effective position measurement system.

Brief Description of the Drawings

[0019] [Figure 1] It is a diagram for explaining the data collection system according to the present invention. [Figure 2] It is a diagram for explaining the terminal of the data collection system according to the present invention. [Figure 3] It is a diagram for explaining the management node of the data collection system according to the present invention. [Figure 4] It is a diagram for explaining the frame transmitted from the terminal to the management node. <00001​ [Figure 6] This is a diagram illustrating the data collection system according to the present invention. [Figure 7] This diagram illustrates the operation of the data collection system according to the present invention. [Figure 8] This is a diagram explaining the fingerprinting method. [Figure 9] This is a diagram illustrating the three-point positioning method and the WCL method. [Figure 10] This is a diagram illustrating the data collection system according to the present invention. [Figure 11] This is a diagram illustrating the data collection system according to the present invention. [Figure 12] This diagram illustrates the operation of the data collection system according to the present invention. [Modes for carrying out the invention]

[0020] Embodiments of the present invention will be described with reference to the attached drawings. The embodiments described below are examples of the present invention, and the present invention is not limited to these embodiments. In this specification and in the drawings, components with the same reference numerals refer to the same components.

[0021] (Embodiment 1) This embodiment describes the basic configuration of the data collection system. Figure 1 is a diagram illustrating the data acquisition system 301 of this embodiment. The data acquisition system 301 is a data acquisition system that utilizes the extended domain of standardized communication protocols (LLDP, HTIP, IEEE802.11, etc.) to perform communication from terminal 11 to network device 12. Terminal 11 stores the sensing data detected by the sensor device in an area within the frame defined by the communication protocol, different from the area where metadata is stored, and sends it to the network device 12. The network device 12 forwards the frame to the management node 13. The management node 13 associates and stores the sensing data and the metadata based on the information identifying the terminal 11 described in the frame. It is characterized by the following:

[0022] The data collection network 15 is a network that connects sensor terminals 11 located within a specific range to a management node 13. The data collection network 15 can be, for example, a local area network (LAN), a field area network (FAN), or an IoT area network. Within the same data collection network 15, there may be multiple sensor terminals 11 of a single type, or there may be multiple types of sensor terminals.

[0023] Figure 2 is a diagram illustrating terminal 11. Terminal 11 is, for example, an IoT sensor terminal that performs sensing on an object to be observed and generates sensing data. Terminal 11 includes a sensor device 11a, a sensing data storage processing unit 11b, an equipment information storage processing unit 11c, a protocol operation unit 11d1, a metadata detection unit (11e1, 11e2, 11e3, ...), and a metadata storage processing unit 11f.

[0024] The sensor device 11a performs sensing on the object being observed and acquires sensing data (main data). Sensing data includes, for example, temperature, image, acceleration, sound, light, CO2, etc. The device information storage processing unit 11c collects information about the device being observed (for example, the manufacturer name, model name, model number, etc.) and stores this information in a predetermined location in the frame (an area that can be used for proprietary purposes, such as the "extended area" or "optional area" defined in the protocol).

[0025] The sensing data storage processing unit 11b stores the sensing data from the sensor device 11a in a predetermined location in the frame (such as the payload portion defined by the protocol). The sensing data storage processing unit 11b may also process the sensing data to fit the format / limitations of the frame's unique extension area, such as by converting it into a certain abbreviated code or by splitting it into multiple frames (fragmentation), before storing it in the frame.

[0026] The sensing data storage processing unit 11b can arbitrarily set the timing for storing sensing data in a frame. For example, the storage timing can be set to each time the sensing data is updated, or the sensing data can be stored after being accumulated for a certain period of time, rather than sequentially. In addition, if the sensing data storage processing unit 11b has accumulated sensing data for a certain period of time, it may also store the record (log) of that data or the results of specific calculations / statistical processing in a frame.

[0027] The type of sensing data stored in the frame and the timing of storage may be fixed or variable. The type of sensing data and the timing of storage may be dynamically changed based on the sensor terminal 11's own judgment, or on instructions from the data analysis unit 13 or the data collection unit 12. Furthermore, the frame transmission period may be fixed or variable. The frame transmission period may also be dynamically changed based on the sensor terminal 11's own judgment or instructions from the data analysis unit 13 or the data collection unit 12.

[0028] The metadata detection unit 11e acquires information other than device information (metadata). Information other than device information includes, for example, location information, time information, person, object, or event information of the detection target, and other information. However, the present invention is not limited to this information other than device information. To acquire this information, the metadata detection unit 11e has a location information detection unit 11e1, a time detection unit 11e2, a person, object, or event detection unit 11e3, and other detection units.

[0029] The location information detection unit 11e1 is, for example, a GPS, an accelerometer, a gyroscope, or an RSSI receiver such as a Wi-Fi signal or a BLE beacon signal. The location metadata detected by the location information detection unit 11e1 is location information obtained from GPS signals, BLE beacon signals, radio wave information from wireless communication, non-communication radio wave information (television, radio, radio-controlled clocks, and other noise, etc.), power information, visible light information, sound wave information, vibration information, acceleration information, and other location metadata sources.

[0030] The time detection unit 11e2 is, for example, a receiver of information from GPS, NTP (Network Time Protocol), etc. The time metadata detected by the time detection unit 11e2 is time-related information obtained from GPS signals, NTP information, and other time metadata sources.

[0031] The person, object, and event detection unit 11e3 is a receiver that receives information from sources such as BLE beacons (carried by a person), smartphones carried by a person, and image analysis results. The person, object, or event metadata detected by the person, object, and event detection unit 11e3 is information about people, objects, or events obtained from BLE beacons carried by a person, smartphones carried by a person, image analysis results, and other sources of timely metadata.

[0032] Other metadata detected by the detection unit includes information about the network configuration.

[0033] The metadata detection unit 11e may detect all of the multiple detection targets, or it may detect any one of them.

[0034] The metadata storage processing unit 11f stores the data detected by the metadata detection unit 11e as metadata in the extended area or optional area within the frame, as defined by the communication protocol. For example, the metadata storage processing unit 11f can store metadata in the control system frame of an IEEE 804.11 wireless LAN. Specifically, it stores various metadata in the "Vendor Specific" area, which is the extended area of ​​the Probe Request frame. Alternatively, it stores various metadata in the "Vendor Specific" area, which is the extended area of ​​the Probe Response frame.

[0035] The metadata storage processing unit 11f may store metadata in a frame after processing it, such as by converting it into a certain abbreviated code and storing it, or by splitting it and storing it in multiple frames (fragmentation), in order to conform to the format / limitations of the frame's unique extension area.

[0036] The metadata storage processing unit 11f can arbitrarily set the timing for storing metadata in a frame. For example, the storage timing can be set to each time the metadata is updated, or the metadata can be stored after a certain period of accumulation rather than sequentially. Furthermore, when metadata has been accumulated for a certain period, the metadata storage processing unit 11f may store the record (log) of that data or the results of specific calculations / statistical processing in a frame.

[0037] The type and timing of metadata stored in a frame may be fixed or variable. The type and timing of metadata storage may be dynamically changed based on the terminal 11's own judgment or instructions from the management node 13.

[0038] The protocol operation unit 11d1 transmits a frame containing sensing data and device information in a predetermined area and metadata in an extended area or optional area to the network device 12 using a lightweight, standardized communication protocol such as LLDP or HTIP. The communication protocol of the frame containing the sensing data and the communication protocol of the frame containing the device information may be the same or different. In the latter case, the metadata storage processing unit 11f may store the metadata in a frame of either one of the communication protocols (either the frame containing the sensing data or the frame containing the device information), or it may store it in frames of both communication protocols (the frame containing the sensing data and the frame containing the device information).

[0039] Furthermore, terminal 11 also has the function of operating in accordance with instructions from a management node, etc. Specifically, terminal 11 has an instruction interpretation unit 11g, and when it changes the BLE beacon signal or metadata information (information to be transmitted, radio wave strength, transmission frequency, etc.) transmitted by the terminal itself in accordance with instructions from the management node 13, it transmits that information to the outside. When transmitting information using the same protocol as communication with network device 12, it operates the communication protocol operation unit 11d1. When transmitting information using a different protocol than communication with network device 12, in addition to the communication protocol operation unit 11d1, it is equipped with a communication protocol operation unit 11d2, and operates the communication protocol operation unit 11d2.

[0040] This also includes cases where terminal 11 itself is a beacon signal source for other terminals to grasp metadata. For example, terminal 11 may be a beacon signal source for identifying location metadata, or it may be a beacon terminal carried by a worker to identify nearby people.

[0041] The network device 12 is, for example, a network switch, a wireless access point, or a wireless repeater. The network device 12 sends the frame group uploaded from the lower-level data collection network 15 directly to the management node 13. Here, the network device 12 may have a metadata processing unit (metadata detection unit 11e and metadata storage processing unit 11f) for metadata possessed by the terminal 11. Even if the network device 12 does not have a sensor device 11a, it can add unique information such as its own MAC address and metadata such as connection port to the frame sent from the terminal 11 and forward it to the management node 13. If the network device 12 has a metadata processing unit, it becomes possible to understand the logical connections from the management node 13 to the terminal 11, and to create a more accurate logical / physical network management map. In other words, even if the network device 12 is a network switch (switching hub) or wireless repeater that does not have Layer 3 or higher functionality, this technology operates at Layer 2, making it possible to manage and understand the connections of network devices, including the network device 12.

[0042] Figure 3 illustrates the management node 13. The management node 13 comprises a protocol operation unit 13a, an information processing unit 13b, and an information storage unit 13c. The management node 13 extracts and stores information from frames received from the network device 12 and uses it for analysis. In particular, the management node 13 is characterized by its function of storing combinations of two or more collected pieces of information in the information storage unit 13c.

[0043] The protocol operation unit 13a receives frames containing sensing data and metadata from terminals 11 and network devices 12. The information processing unit 12b extracts sensing data, device information, and metadata from the received frames and organizes them in the information storage unit 13c based on information that identifies the individual terminal 11 (e.g., MAC address). (1) Physical information of the terminal (information such as the characteristics of the casing, image information, information on attached labels, the object the worker is pointing to, the object the worker is looking at, etc.) (2) Identifier of a terminal on the logical network (MAC address, UUID, etc.) (3) Main data (sensing data such as temperature, image, acceleration, sound, light, CO2, etc.) (4) Various metadata (data such as location, time, people, things, events, etc.) For example, the management node 13 refers to metadata about a location and stores primary data obtained from the same location or within a certain area in the format [location metadata, primary data]. [supplement] Let me add some information about location metadata. In some cases, like GPS information, the location metadata is directly determined at the time it is sensed by terminal 11. On the other hand, in some cases, such as signals from BLE beacons, visible light, or sound information, it is not determined whether the information is location information at the time it is sensed by terminal 11 and sent as metadata, and the management node 13 recognizes / understands the metadata as location metadata. [End of supplementary information]

[0044] Figure 4 illustrates a frame 41 transmitted from terminal 11 to management node 13. The network device 12 is omitted from Figure 4. Frame 41 is a Layer 2 communication frame, such as an Ethernet® frame or a Wi-Fi communication frame. Frame 41 consists of a logical identifier 41a of the communication device, such as a MAC address; a source and destination identifier 41b, such as an IP address; an area 41c where sensing data such as temperature and images are stored; and an extended area 41d where metadata is stored. Of these, the identifier 41b and area 41c constitute a Layer 3 communication packet.

[0045] The management node 13, for example, combines the MAC address of the logical identifier 41a with the location metadata of the extended area 41d to create [MAC address, location metadata], and combines the MAC address of the logical identifier 41a with the installer metadata of the extended area 41d to create [MAC address, installer metadata], and organizes this information in the information storage unit 13c.

[0046] Thus, the data acquisition system 301 can acquire network configuration information, device information, sensor data, and metadata of terminals and devices using a communication protocol that does not require high performance.

[0047] (Embodiment 2) Figure 5 illustrates the data collection system 302 of this embodiment. The data collection system 302 can determine the location of communication devices in space without the need to accurately deploy a large number of BLE beacons in advance or to introduce an expensive positioning system.

[0048] Specifically, the data collection system 302 is a data collection system comprising a management node 13 and a plurality of communication terminals 14, The communication terminals 14 transmit and receive radio waves to each other at any time, and notify the management node 13 of the received strength of the radio waves. The management node 13 calculates the relative position of the communication terminal 14 from the notified received signal strength. It is characterized by the following.

[0049] In this embodiment, the case where there are three communication terminals 14 is described, but the number of communication terminals 14 in the data collection system of the present invention is not limited to three. Here, the communication terminal 14 may be a terminal 11 equipped with a sensor device as described in Figure 2, or it may be a location-aware terminal such as a BLE beacon that serves as a location metadata source in Embodiment 3 described later. In addition, the communication terminal 14 may be a terminal that can collect various sub-sensor data that can be used as metadata. Furthermore, the communication terminal 14 may be a stationary type with a fixed position, a portable type whose position can be freely changed, or a patrol robot type that makes regular rounds.

[0050] Figure 6 is a diagram illustrating the functional blocks of the data acquisition system 302. The communication protocol operation unit 13a of the management node 13 includes a data communication transmission unit 13d and a data communication reception unit 13e. Each communication device 14 includes a data communication receiving unit 14a, a data communication transmitting unit 14b, a beacon signal receiving unit 14c, a beacon signal transmitting unit 14d, and a processing unit 14e. Alternatively, the terminal 11 described in Figure 2 may be modified into a communication terminal 14 by adding a data communication receiving unit 14a, a data communication transmitting unit 14b, a beacon signal receiving unit 14c, a beacon signal transmitting unit 14d, and a processing unit 14e.

[0051] Figure 7 is a sequence diagram illustrating the terminal location determination method performed by the data collection system 302. This terminal location determination method is as follows: Sending and receiving radio waves between multiple communication terminals at any time (step S14), The communication terminal notifies the management node 13 of the received strength of the radio waves it has received (step S18), and The management node 13 calculates the relative position of the communication terminal from the received signal strength that has been notified (step S20). To do so.

[0052] I will explain in more detail. The information processing unit 13b of the management node 13 outputs an instruction to transmit a beacon signal with intensity X to a desired communication terminal (communication terminal 14-1 in this embodiment) at any time (step S10). The data communication transmission unit 13d receives the instruction and outputs an instruction signal to transmit a beacon signal to communication terminal 14-1 with intensity X (step S11).

[0053] The data communication receiving unit 14a of communication terminal 14-1 receives the instruction signal and notifies the processing unit 14e (step S12). The processing unit 14e instructs the beacon signal transmitting unit 14d to transmit a beacon signal at strength X based on the notification (step S13). The beacon signal is received by the beacon signal receiving units 14c of other communication terminals (in this embodiment, communication terminals 14-2 and 14-3) (step S14). The processing unit 14e of the other communication terminals confirms the received strength Y of the beacon signal received by the beacon signal receiving unit 14c (steps S15, S16). The processing unit 14e of the other communication terminals notifies the data communication transmitting unit 14b that the received strength of the beacon signal is Y (step S17). The data communication transmitting unit 14b of the other communication terminals transmits a response signal to the management node 13 indicating that the received strength of the beacon signal is Y (step S18).

[0054] The data communication receiving unit 13e of the management node 13 notifies the information processing unit 13b of the content of the response signal (step S19). The information processing unit 13b of the management node 13 calculates the relative position of the communication terminal from the content of the response signal, based on the difference or ratio between intensity X and intensity Y (step S20).

[0055] Then, the management node 13 repeatedly calculates the relative position by changing the transmission strength of the radio waves transmitted by the communication terminal 14. Specifically, the data communication receiving unit 13e of the management node 13 decides to change the strength X (step S21). After that, steps S10 to S21 are repeated a predetermined number of times.

[0056] In this embodiment, an example was described in which the management node 13 transmits a beacon signal to the communication terminal 14-1, but the same applies when transmitting a beacon signal to other communication terminals. That is, the data collection system 302 transmits and receives beacon signals between multiple communication terminals 14 and determines the relative position of the communication terminals 14 from the relationship between the transmitted strength X and the received strength Y.

[0057] Furthermore, it is preferable that the transmission strength X and reception strength Y of the communication between the management node 13 and the communication terminal 14 (the instruction signal in step S11 and the response signal in step S18) are stored in the extended area of ​​the Layer 2 communication protocol. By performing this through the extended area of ​​the Layer 2 communication protocol, the relative position of the communication terminal 14 can be determined with low load and low latency (because IP connection establishment is not required). Since the relative position can be determined with low load and low latency, the relative position of the communication terminal 14 can be confirmed at any time, and it is possible to track the movement of the communication terminal 14.

[0058] Traditionally, in order to confirm the location of the communication terminals under management, workers had to manually and accurately register the physical positions between fixed beacons and the output signal strength of each beacon in a database beforehand. However, with the data collection system 302, the relative position of the communication terminals can be confirmed by instructions from the management node 13, eliminating the need for workers to manually register terminals or input signal strength information.

[0059] [Relative position calculation method] This section explains how the management node 13 calculates the relative position of the communication terminal in step 20. (Step 1) The distance between two communication terminals is calculated from the received signal strength Y and the transmitted signal strength X. The received signal strength Y is, for example, the RSSI value (Received Signal Strength Indicator), which the sensor generates as a numerical value when it receives a signal. The formula for calculating the distance d between two communication terminals is as follows: d=10 ((X-Y) / N×10) Here, N is a coefficient that changes depending on the environment of the space where the beacon is placed. In an ideal space without obstacles, N=2.0, In a space where radio waves propagate while reflecting, N < 2.0, In a space where the signal is absorbed and attenuated by obstacles as it propagates, N > 2.0, Set it like this. <Specific measurement methods> The system transmits a beacon signal in a sweeping pattern to any given communication terminal, changing the transmission strength from weak to strong, and mutually collects RSSI between that terminal and nearby communication terminals. Performing such sweeping transmit signals increases the amount of reference information available, making it easier to estimate the distance d and the coefficient N.

[0060] To measure the distance between a beacon and a sensor using beacon signals, it is preferable to have a signal strength reference value. While distance measurement is possible using only the RSSI, the accuracy of the measurement depends on whether the RSSI is greater than or less than the reference value. By comparing these two values, it is possible to determine that the distance is within 1 meter if the RSSI is greater than the reference value, and further otherwise. The signal strength reference value is the RSSI value when received at a distance of 1 meter from the transmitting device. It is attached to the end of the beacon information when the beacon is transmitted. This value exists only in the iBeacon® and AltBeacon formats.

[0061] (Step 2) Step 2 involves obtaining the distance d between multiple communication terminals as in Step 1, and estimating their approximate relative positions in planar / three-dimensional space. Estimation methods include, for example, the fingerprint method, tripoint positioning, and weighted centroid method (WCL method). Step 2 can use any one or more of these methods.

[0062] (1) Fingerprint method Figure 8 illustrates the fingerprinting method. As shown in Figure 8(A), the space is allocated to the area of ​​the communication terminal 14. We consider estimating the position of communication terminal 14-i. First, we obtain the RSSI between the four communication terminals 14 (see Figure 8(B)). Here, if the RSSI between communication terminal 14-i and other communication terminal 14 is as follows, RSSI = 59 with communication terminal 14-1 RSSI = 48 with communication terminal 14-2 RSSI = 80 with communication terminal 14-3 RSSI = 70 with communication terminal 14-4 It can be estimated that communication terminal 14-i is located in area 2.

[0063] (2) Three-point positioning method Figure 9 illustrates the tripartite positioning method. As in Procedure 1, the distances (d1, d2, d3) between three or more communication terminals (e.g., 14-1, 14-2, 14-3) and communication terminal 14-i are obtained, and a point is determined where the circumferences from the locations of each communication terminal (14-1, 14-2, 14-3) intersect. This point is then estimated to be the position of communication terminal 14-i.

[0064] (3) WCL method Figure 9 also illustrates the WCL method. As in step 1, the distances (d1, d2, d3) between three or more communication terminals (e.g., 14-1, 14-2, 14-3) and communication terminal 14-i are obtained. From these distances, "weights" are calculated, and the position of communication terminal 14-i is estimated from the balance between these "weights". Compared to triangulation, this method is expected to reduce computational costs and improve noise immunity.

[0065] (Embodiment 3) The data collection system 302 described in Embodiment 2 requires the implementation of a beacon signal transmission / reception unit (14c, 14d) and a low-level communication protocol extension function (a function equivalent to the metadata storage processing unit 11f described in Figure 2) in addition to the main communication (data communication transmission / reception unit (14a, 14b)) in the communication terminal 14, as described in Figure 6. However, modifying existing terminals (such as sensor terminals) to add these functions is difficult, hindering widespread adoption. Therefore, in this embodiment, we will describe a data collection system 303 that can determine the location of the existing terminal 10 by placing a communication terminal 14 capable of collecting low-level metadata in the vicinity without modifying the existing terminal 10.

[0066] Figure 10 is a diagram illustrating the data collection system 303. The data acquisition system 303 is Management node 13 and An existing terminal 10 acquires sensing data and outputs it wirelessly as main data D1, Access point 12-1 receives the main data D1 wirelessly output by the existing terminal 10 and forwards it to the management node 13, A communication terminal 14 wirelessly outputs metadata D2 obtained from metadata source 16, Access point 12-2 receives metadata D2 wirelessly output by communication terminal 14 and forwards it to management node 13, It is equipped with. The communication method between the existing terminal 10 and access point 12-1, and between the communication terminal 14 and access point 12-2, is, for example, Wi-Fi.

[0067] Management node 13 is To obtain the positional relationship between the existing terminal 10 and the communication terminal 14, and The information regarding the existing terminal 10 obtained from the aforementioned positional relationship is used as metadata, and the main data D1 and metadata D2 are linked and stored together. Further steps are taken.

[0068] The communication terminal 14 can acquire its own position using the method described in Embodiment 2. The communication terminal 14 also acquires the distance to the existing terminal 10. The method for acquiring this distance may be set by the operator, or it may be acquired by communicating with the existing terminal 10 and obtaining it from RSSI values ​​or the like. Furthermore, if the communication terminal 14 is adjacent to the existing terminal 10, the position of the communication terminal 14 may be used as the position of the existing terminal 10.

[0069] The existing terminal 10 acquires sensing data at any given time and wirelessly outputs it as main data D1. At this time, the communication terminal 14 communicates with the existing terminal 10 and determines the time at which the existing terminal 10 with MAC address xxx sent the main data D1, and how far away it is (step S31). Then, the communication terminal 14 wirelessly outputs this information and location information as metadata D2. At this time, the communication terminal 14 may acquire other information from the metadata source (see Figure 1) and include it in metadata D2.

[0070] The management node 13 associates and stores the main data D1 and metadata D2 based on the MAC address and time information contained in metadata D2 and the MAC address and time information contained in main data D1 (step S32). Furthermore, since the communication terminal 14 and access point 12-2 communicate at Layer 2, connection establishment is unnecessary, and the management node 13 can acquire metadata D2 with low latency.

[0071] In this way, the data collection system 303 can collect metadata without modifying the existing terminal 10 or access point 12-1 and without interfering with the main communication (main data).

[0072] (Embodiment 4) This embodiment also describes a data collection system 304 that can determine the location of the existing terminal 10 by placing a communication terminal 14 capable of collecting low-level metadata in the vicinity, without making any modifications to the existing terminal 10.

[0073] Figure 11 is a diagram illustrating the data acquisition system 304. The data acquisition system 304 and the data acquisition network 15 are, for example, a wired LAN. The data acquisition system 304 is, Management node 13 and An existing terminal 10 acquires sensing data and outputs it as main data D1, A communication terminal 14 receives the main data D1 output by the existing terminal 10 and outputs it together with metadata D2 obtained from the metadata source 16, A gateway 12-3 receives the main data D1 and metadata D2 output by the communication terminal 14 and forwards them to the management node 13. It is equipped with. Existing terminals 10 include, for example, surveillance cameras and business phones that operate using PoE (Power over Ethernet).

[0074] The communication terminal 14 is inserted into the LAN cable 15a between the existing terminal 10 and the gateway 12-3. In particular, it is preferable that the communication terminal 14 be located near the existing terminal 10 in order to collect metadata about the location and environment of the existing terminal 10. The communication terminal 14 can acquire its own location using the method described in Embodiment 2, and this location is set as the location of the existing terminal 10.

[0075] The existing terminal 10 acquires sensing data at any given time and outputs it as main data D1 over the LAN cable 15a. The communication terminal 14 basically passes the main data D1 through the gateway 13. The communication terminal 14 transparently forwards the Ethernet frame containing the main data D1 to the upstream network and sends metadata D2, which includes information such as its own location, its own identifier (MAC address, etc.), the identifier of the main data source (MAC address, etc.), and the order of the nodes it passed through, into an LLDP frame to the upstream network. At this time, the communication terminal 14 may acquire other information from the metadata source (see Figure 1) and include it in the metadata D2.

[0076] The management node 13 stores the main data D1 included in the same LLDP frame in association with it. Furthermore, since the communication terminal 14 and gateway 12-3 communicate at Layer 2, connection establishment is unnecessary, and the management node 13 can obtain metadata D2 with low latency.

[0077] In this way, the data collection system 304 can collect metadata without modifying the existing terminal 10 or gateway 12-3 and without interfering with the main communication (main data).

[0078] (Embodiment 5) Figure 12 is an overall diagram illustrating the operation of the data acquisition system described in Embodiments 2 to 4. The flow of main data D1 is shown by a dotted line, and the flow of metadata D2 is shown by a dashed line. (Step S51) The management node 13 determines the relative position of the communication device 14 using the method described in Embodiment 2. At this time, the management node 13 not only knows the communication device 14, but also the relative position of the BLE beacon 17 if the data collection system is equipped with a BLE beacon 17. (Step S52) The management node 13, using the method described in Embodiment 3, ascertains the presence of existing terminals 10 located near each communication terminal 14, and the presence of access points 12-1 communicating with them. Here, the management node 13 obtains the MAC addresses of the existing terminals 10 via the communication terminals 14. The management node 13 also calculates the distance between the communication terminals 14 and the existing terminals 10 based on the strength of Wi-Fi wireless information, etc. Then, the management node 13 calculates the location of the existing terminals 10 by comparing this information with the information obtained in step S51. (Step S53) The management node 13 stores the main data D1, which was transferred via access point 12-1, and the metadata D2, which was transferred via access point 12-2, linked together based on the MAC address of the existing terminal 10 and the acquisition time of the main data sensing data. (Step S54) The management node 13 may use the information obtained in steps S51 and S52 to create a floor map showing the locations of existing terminals 10.

[0079] As described above, the data collection system according to the present invention improves the accuracy of determining location on a floor map by actively changing the settings of the communication terminal 14, access point 12-1, and beacon 17 to measure relative positions and distances. For this reason, the data collection system according to the present invention does not require the precise deployment of a large number of BLE beacons in advance or the introduction of an expensive positioning system. [Explanation of symbols]

[0080] 10: Existing devices 11: Sensor terminal 11a: Sensor device 11b: Sensing data storage unit 11c: Equipment information storage unit 11d1, 11d2: Protocol operation unit 11e, 11e1, 11e2, 11e3, ...: Metadata detection unit 11f: Metadata storage processing unit 11g: Instruction Interpretation Section 12: Network devices 12-1, 12-2: Access Point 12-3: Gateway 13: Management Node 13a: Communication protocol operation unit 13b: Information Processing Section 13c: Information storage section 14, 14-1, 14-2, 14-3, ...: Communication devices 14a: Data communication receiving unit 14b: Data communication transmission unit 14c: Beacon signal receiver 14d: Beacon signal transmitter 14e: Processing Unit 15: Data Collection Network 15a: LAN cable 16: Metadata Source 41: Frame 41a: Logical identifier 41b: Source / Destination Identifier 41c: Main data area 41d: Extended area 301-304: Data collection system

Claims

1. A management node of a data collection system equipped with multiple communication terminals, The aforementioned communication terminal includes a data communication receiving unit that transmits and receives radio waves from each other at arbitrary timings and notifies the measured received strength of the radio waves, An information processing unit that calculates the relative position of the communication terminal from the notified received signal strength, Equipped with, The management node is characterized in that the information processing unit causes the transmission intensity of the radio waves transmitted to the communication terminal to vary and repeatedly calculates the relative position.

2. The management node according to claim 1, characterized in that the data communication receiving unit notifies the received strength by receiving a frame in which the received strength is stored in the extended area of ​​the Layer 2 communication protocol.

3. The aforementioned information processing unit, To obtain the positional relationship between the sensing terminal that acquires sensing data and the communication terminal, and The information regarding the sensing terminal obtained from the aforementioned positional relationship is used as metadata, and the sensing data and the metadata are linked and stored in the information storage unit. The management node according to claim 1, further characterized by performing the following.

4. A communication terminal that communicates with the management node of the data acquisition system, A data communication receiving unit that receives instruction signals from the management node, A beacon signal transmitting unit that transmits radio waves based on the instruction signal, A beacon signal receiving unit that receives radio waves from other communication terminals, A processing unit for measuring the received signal strength of the aforementioned radio waves, A data communication transmission unit that notifies the management node of the received signal strength, Equipped with, The communication terminal is characterized in that the beacon signal transmitting unit varies the transmission intensity of the radio waves transmitted based on the instruction signal.

5. The communication terminal according to claim 4, characterized in that the data communication transmission unit transmits and notifies by transmitting a frame in which the received strength has been stored in the extended area of ​​the communication protocol of Layer 2.

6. The ability to send and receive radio waves between multiple communication terminals at any given time. The communication terminal notifies the management node of the received signal strength of the radio waves it has received, and The management node calculates the relative position of the communication terminal from the received signal strength that has been notified. A method for determining the location of a terminal, A terminal position determination method characterized by repeatedly calculating the relative position by varying the transmission intensity of the radio waves transmitted to the communication terminal when calculating the relative position.

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