KR102078181B1 - Tracking relative position of nodes system and method of the same - Google Patents

Abstract

The present invention provides a communication apparatus which transmits an RSS signal in both directions with each other, and comprises a plurality of nodes; An operation sensor installed in the node and configured to determine each of the plurality of nodes as a fixed node or a mobile node by the movement of the node; And a position determining unit for estimating a relative position of the at least one mobile node and another node based on the presence of the fixed node.

Description

Relative position tracking system of node and relative position tracking method of node {TRACKING RELATIVE POSITION OF NODES SYSTEM AND METHOD OF THE SAME}

The present invention relates to a relative position tracking system of a node and a relative position tracking method of a node applicable to a situation where a plurality of nodes are variable as moving or fixed nodes.

Location recognition technology in the sensor network environment is a technique for estimating the relative position using information such as distance or angle from a known position, and calculating the position of nodes using the same.

Common methods for measuring location in a sensor network environment include various technologies such as infrared, ultrasonic, RFID, UWB, RSSI, camera sensor, and light.

Among the various techniques described above, the position measurement technique using the received signal strength RSSI (Received Signal Strength Indication) of the sensor node is not easy to use directly because the RSSI varies greatly depending on the characteristics of the surrounding environment. Many studies are being conducted to measure distance using such irregular RSSI values.

In addition, in order to detect the location of the node, techniques such as event detection, location awareness dependent computing, and geographic tracking are required. Although much research has been conducted on reliability and data reliability from the viewpoint of sensor networks, there is a need for a method and system that can secure the reliability of hand signals in location recognition.

Korea Patent Registration 10-1052097 (Invention name: Location management system and method of wireless sensor node, Announcement date: July 26, 2011)

One object of the present invention is to estimate the relative position of nodes when a state change occurs between nodes or when the structure between nodes is variable.

In order to solve the above problems, the relative position tracking system of the node of the present invention is to communicate by transmitting RSS signals in both directions between each other, the node consisting of a plurality; An operation sensor installed in the node and configured to determine each of the plurality of nodes as a fixed node or a mobile node by the movement of the node; And a position determining unit estimating a relative position of the at least one mobile node and another node based on the presence of the fixed node.

According to an example related to the present disclosure, the location determining unit, when the fixed node exists, uses the distance information and the RSS signal between the fixed nodes to determine a relative position between the at least one mobile node and another node. Estimate.

According to another example related to the present disclosure, when the fixed node does not exist, the position determining unit estimates a relative position of the at least one mobile node and another node by using an RSS signal between the mobile nodes. do.

According to another example related to the present invention, the motion sensor determines that the voltage generated by the movement of the plurality of nodes is greater than or equal to the predetermined voltage value, and determines the mobile node, and the voltage value generated by the movement of the plurality of nodes. If it is less than the predetermined voltage value, it is determined as a fixed node.

According to another example related to the present disclosure, the position determining unit estimates a relative position of the at least one mobile node and another node based on distance information between the nodes and an RSS signal between the nodes.

In order to solve the above another problem, the relative position tracking method of the node comprises the steps of detecting the movement of the plurality of nodes by the motion sensor to determine the plurality of nodes as a fixed node or a mobile node; And a position estimating step of estimating a relative position of the mobile node with another node based on the presence of the fixed node.

According to an example related to the present disclosure, the position estimating may include, when the fixed node exists, a relative position between the at least one mobile node and another node using distance information between the fixed nodes and an RSS signal. Estimating.

According to another example related to the present disclosure, the location estimating step may be performed by using an RSS signal between the mobile nodes to determine a relative position between the at least one mobile node and another node when the fixed node does not exist. Estimating.

According to another example related to the present invention, the method for tracking a relative position of a node further includes correcting an RSS signal between the plurality of nodes.

The present invention is free to attach, move, and change the number of nodes as necessary, so that the nodes can be installed at any position as needed rather than a fixed position.

According to the present invention, when an operation of a fixed node occurs, the mobile node is converted to a mobile node, and when the mobile node is no longer operated, the mobile node is converted to a fixed node, and the relative position of the node can be estimated based on this.

According to the present invention, since the fixed / mobile node is determined by the motion sensor itself and the relative relationship can be estimated even when there is no fixed node, the dynamic situation or the node state is variable as well as the existing fixed type of location service. Applicable to

The present invention can be utilized for parking confirmation service and indoor location service by further improving location estimation performance within a short distance based on RSS signal.

1 is a conceptual diagram of a relative position tracking system of a node of the present invention.
2A is a graph illustrating an example of a signal generated by a motion sensor in a mobile node of the present invention.
2B is a graph illustrating an example of a signal generated by a motion sensor at a fixed node of the present invention.
3 is a conceptual diagram illustrating an example of transmitting and receiving a signal between nodes of the present invention.
4 is a flowchart of a method for tracking relative positions of nodes of the present invention.

Hereinafter, exemplary embodiments disclosed herein will be described in detail with reference to the accompanying drawings, and the same or similar components will be given the same or similar reference numerals, and redundant description thereof will be omitted. The suffix "part" for the components used in the following description is given or mixed in consideration of ease of specification, and does not have a meaning or role distinguished from each other. In addition, in describing the embodiments disclosed herein, when it is determined that the detailed description of the related known technology may obscure the gist of the embodiments disclosed herein, the detailed description thereof will be omitted. In addition, the accompanying drawings are intended to facilitate understanding of the embodiments disclosed herein, but are not limited to the technical spirit disclosed herein by the accompanying drawings, all changes included in the spirit and scope of the present invention. It should be understood to include equivalents and substitutes.

Terms including ordinal numbers such as first and second may be used to describe various components, but the components are not limited by the terms. The terms are used only for the purpose of distinguishing one component from another.

When a component is referred to as being "installed" and "connected" to another component, it should be understood that there may be other components in between, although it may be directly installed and connected to the other component. .

Singular expressions include plural expressions unless the context clearly indicates otherwise.

In this application, the term "comprises" and the like is intended to indicate that there is a feature, number, step, operation, component, part or combination thereof described in the specification, but one or more other features or numbers, step It is to be understood that the present disclosure does not exclude the possibility of the presence or the addition of any operation, a component, a part, or a combination thereof.

The relative position tracking system 100 of a node of the present invention includes a node 10, a motion sensor 20, and a position determining unit 30.

The node 10 is composed of a plurality of nodes, the plurality of nodes 10 communicate with each other by transmitting the RSS signal in both directions. The node 10 may be a fixed node 10a or a mobile node 10b, as described below, and the node 10 may be referred to as a sensor network.

The fixed node 10a and the mobile node 10b of the present invention may include any device or sensor node capable of transmitting and receiving RF (Radio Frequency) having a constant intensity.

The RSS signal may be a signal based on received signal strength (RSS).

The plurality of nodes 10 may acquire the strength of the received signal by sensing the strengths of the signals transmitted between the nodes 10.

The plurality of nodes 10 may be understood as variable nodes capable of forming the relative position tracking system 100. The relative position tracking system 100 of the variable node may be understood as a system in which each of the plurality of nodes 10 may be flexibly changed to a moving or fixed node 10a. In addition, the relative position tracking system 100 of the variable node may be understood as a system in which the number or operating position of the node 10 may vary.

The motion sensor 20 is installed in the node 10. For example, the motion sensor 20 may be installed in each of the plurality of nodes 10. The motion sensors 20 may determine the plurality of nodes 10 as the fixed node 10a or the mobile node 10b, respectively.

The motion sensor 20 determines whether the motion of the node 10 is detected as a fixed node 10a or a floating node.

For example, the motion sensor 20 detects the movement of the node 10 and transmits a voltage value. If the transmitted voltage value is greater than or equal to a predetermined voltage value, the operation sensor 20 determines the mobile node 10b, and the transmitted voltage value is If it is less than the predetermined voltage value, it can be determined by the fixed node (10a).

The motion sensor 20 may be, for example, an inertial measurement unit (IMU).

2A and 2B illustrate examples of voltage values transmitted by the motion sensor 20 installed in the node 10, and FIG. 2A illustrates examples of voltage values exceeding a predetermined voltage value by the movement of the node 10. It is determined that the mobile node 10b. In FIG. 2B, an example in which the node 10 is hardly moved and a voltage value of less than or equal to a predetermined voltage value is transmitted is illustrated, which is determined as the fixed node 10a.

The position determining unit 30 is configured to estimate a relative position of the at least one mobile node 10b and another node 10 based on the presence of the fixed node 10a.

The position determining unit 30 may be electrically connected to the plurality of nodes 10 and the motion sensor 20 or may be connected to enable wired or wireless communication.

When the fixed node 10a is present, the position determining unit 30 uses the distance information and the RSS signal between the fixed nodes 10a and the relative position between the at least one mobile node 10b and another node 10. Can be estimated. In addition, when the fixed node 10a is present, the location determining unit 30 may provide RSS information and distance information between the fixed node 10a and the mobile node 10b or between the mobile node 10b and the mobile node 10b. By further utilizing, it is possible to estimate the relative position of at least one mobile node 10b with another node 10.

In addition, when the fixed node 10a does not exist, the position determining unit 30 utilizes an RSS signal between the mobile nodes 10b to determine a relative position between the at least one mobile node 10b and another node. It can be estimated.

The position determining unit 30 determines time-of-arrival (TOA), time difference of arrival (TDOA), and RSS (received) when estimating the position of the mobile node in the presence of the fixed node and in the absence of the fixed node. Signal Strength, AOA (Angle of Attack), Multihop, etc. may be used.

Referring to Fig. 3, a bidirectional RSS signal will be described.

When the bidirectional RSS signals have different characteristics, the RSS signal may be corrected by a statistical method or by using the motion sensor 20.

By combining the bidirectional RSS signals, higher accuracy distance estimation may be possible.

Since the RSS signal can be transmitted in both directions, all nodes 10 can be switched to the fixed and mobile nodes 10a and 10b, which has been described above.

On the other hand, the relative position tracking method (S100) of the node of the present invention includes the step (S10) and the position estimation step (S20) for determining the plurality of nodes 10 as a fixed node (10a) or a mobile node (10b). .

In the step S10 of determining the plurality of nodes 10 as the fixed node 10a or the mobile node 10b, the motion sensor 20 installed in the plurality of nodes 10 detects the movement of the plurality of nodes 10. By doing so.

For example, in the determining of operation S10, the motion sensor 20 detects the movement of the node 10 and transmits a voltage value. And, if the transmitted voltage value is less than the predetermined voltage value may be performed by allowing the fixed node (10a) to determine.

The position estimating step S20 estimates a relative position between the mobile node 10b and another node 10 based on the presence of the fixed node 10a.

In the case of the position estimating step S20, when the fixed node 10a exists, the position information relative to the at least one mobile node 10b and the other node 10 may be utilized by utilizing the distance information and the RSS signal between the fixed nodes 10a. It may include the step of estimating the position (S23).

In addition, when the fixed node 10a does not exist, the position estimating step S20 utilizes an RSS signal between the mobile nodes 10b so as to be relative to at least one mobile node 10b and another node 10. It may include the step of estimating the position (S25).

The position estimation step S20 may be performed by the position determination unit 30.

When the fixed node 10a is present, the position determining unit 30 uses the distance information between the fixed nodes 10a and the RSS signal to determine a relative position of at least one mobile node 10b and another node. It can be estimated. In addition, when the fixed node 10a is present, the position determining unit 30 includes distance information between the fixed node 10a and the mobile node 10b and an RSS signal or between the mobile node 10b and the mobile node 10b. By using the distance information of the and the RSS signal, it is possible to estimate the relative position of the at least one mobile node (10b) and the other node.

In addition, when the fixed node 10a does not exist, the position determining unit 30 utilizes an RSS signal between the mobile nodes 10b to determine a relative position between the at least one mobile node 10b and another node. It can be estimated.

Relative position tracking method (S100) of the node of the present invention may further comprise the step (S30) of correcting the RSS signal between the plurality of nodes.

Compensating the RSS signal between the plurality of nodes, for example, when the bidirectional RSS signal between the plurality of nodes 10 exhibits different characteristics, the RSS by a statistical method or the use of the motion sensor 20 Can be performed by correction of the signal. In addition, a higher accuracy distance estimation may be possible by combining the bidirectional RSS signals.

The relative position tracking system 100 and the relative position tracking method S100 of the node described above are not limited to the configuration and the method of the embodiments described above, but the embodiments may be modified in various embodiments. All or some of these may optionally be combined.

It is apparent to those skilled in the art that the present invention can be embodied in other specific forms without departing from the spirit and essential features of the present invention. Accordingly, the above detailed description should not be construed as limiting in all aspects and should be considered as illustrative. The scope of the present invention should be determined by reasonable interpretation of the appended claims, and all changes within the equivalent scope of the present invention are included in the scope of the present invention.

100: node relative position tracking system
10: node 10a: fixed node 10b: mobile node
20: motion sensor
30: position determination
S100: How to track the relative position of a node
S10: determining a plurality of nodes as fixed nodes or mobile nodes
S20: position estimation step
S23: estimating the relative position between the mobile node and another node by using the RSS information and distance information between the fixed nodes when the fixed node exists.
S25: estimating the relative position of the mobile node with other nodes by utilizing the RSS signal between the mobile nodes when there is no fixed node

Claims (9)

As a relative position tracking system of a node that can be applied in a situation where a plurality of nodes are variable as moving or fixed nodes,
A node comprising a plurality of nodes which communicate by transmitting RSS signals in both directions with each other;
An operation sensor installed in the node and configured to determine each of the plurality of nodes as a fixed node or a mobile node by the movement of the node; And
A position determining unit for estimating a relative position of the at least one mobile node and another node based on the presence of the fixed node;
If the fixed node does not exist, the location determining unit estimates a relative position of the at least one mobile node and another node by utilizing the RSS signal between the mobile nodes,
The location determining unit, when the fixed node is present, estimates a relative position of the at least one mobile node and another node by using distance information between the fixed nodes and the RSS signal. Relative position tracking system.
delete delete The method of claim 1,
The motion sensor determines the mobile node if the voltage value generated by the movement of the plurality of nodes is greater than or equal to the predetermined voltage value, and determines the fixed node if the voltage value generated by the movement of the plurality of nodes is less than or equal to the predetermined voltage value. Relative position tracking system of the node, characterized in that.
The method of claim 1,
The position determining unit estimates a relative position between the at least one mobile node and another node based on distance information between the nodes and an RSS signal between the nodes.
As a method of tracking the relative position of a node that can be applied when a plurality of nodes are variable as moving or fixed nodes,
Detecting the movement of the plurality of nodes by a motion sensor and determining the plurality of nodes as fixed nodes or mobile nodes; And
A position estimation step of estimating a relative position of the mobile node with another node based on the presence of a fixed node,
The location estimating step includes estimating a relative position of the at least one mobile node and another node by utilizing an RSS signal between the mobile nodes when the fixed node does not exist,
The location estimating step includes estimating a relative position of the at least one mobile node and another node by using the RSS information and distance information between the fixed nodes when the fixed node exists. Relative location tracking method.
delete delete The method of claim 6,
And correcting an RSS signal between the plurality of nodes.

Images