KR101221482B1 - Apparatus and Method for tracing positions of multiple items based on the radio communication - Google Patents

Abstract

The present invention relates to a system for recognizing positions of a plurality of objects based on wireless communication.
According to an embodiment of the present invention, a method of recognizing positions of a main target and a plurality of peripheral targets based on wireless communication may include triangulation using a distance traveled by a moving object and a distance from a position before and after the movement of the moving object to the peripheral target. Measuring the position of the neighboring target, and recalculating the position of the neighboring target using a minimum mean squared error (MMSE) algorithm with the measured position of the neighboring target and a position of another neighboring target. do.

Description

{Apparatus and Method for tracing positions of multiple items based on the radio communication}

The present invention relates to a method and system for recognizing a location of a plurality of objects based on wireless communication.

Regarding a system for tracking the position and direction of things, research is being conducted in many fields and technological advances are being made at a considerable level.

In particular, in order to secure safety in a high-risk environment, various studies are being conducted in relation to the development of a system that can recognize the location of a plurality of objects such as dangerous substances, corresponding equipment, and corresponding personnel based on wireless communication. to be. For example, in the work environment for synthesizing PET (Positron Emission Tomography) radiopharmaceuticals, monitoring of people and equipment entering and exiting the workplace is an important factor for securing workplace safety because PET radiopharmaceuticals are radioactive materials.

In relation to the position and direction tracking technology, Korean Patent No. 0882351 (Registration date: 2009.1.30.) Discloses a device and method for tracking position and direction using the RF signal. Since only the location of the target is tracked, there is a problem that is not applicable to an environment having a plurality of objects.

In addition, Korean Patent Application No. 2010-0118284 (filed date: April 28, 2009) discloses a safety management facility for heavy work operations, the present invention has a problem that requires a base station that already knows the location.

The present invention is to solve the above problems, the problem to be solved by the present invention is based on wireless communication wireless communication that can effectively recognize the location of a plurality of objects without using a base station that already knows the location It is to provide a multi-object position recognition system.

In order to achieve the above object, according to the present invention, a method for recognizing a location of a plurality of objects including a USN-tagged main target and one or more peripheral targets based on a wireless communication, the distance traveled by the moving object, and Measuring the position of the one or more peripheral targets by performing triangulation using respective distances from the position before and after the movement of the moving object to the one or more peripheral targets, the position of one of the one or more peripheral targets measured And recalculating the position of any one of the neighboring targets using a minimum mean squared error (MMSE) algorithm having a position of the remaining neighboring targets of the one or more neighboring targets, wherein the moving object is the USN. And an antenna for receiving a radio signal from the tag.

In addition, according to the present invention, in a method for recognizing a location of a plurality of objects including a USN-tagged main target and one or more peripheral targets on a wireless communication basis, the position of any one of the peripheral targets recalculated is

,

, l_1i 는 상기 이동체가 상기 USN 태그로부터 수신한 상기 어느 하나의 주변 타겟과 상기 나머지 주변 타겟 사이의 거리)이다.Here, the position of any one peripheral target is (x ₁ , y ₁ ), the position of the remaining peripheral target is (x _i , y _i ), and the distance between the one peripheral target and the remaining peripheral target is

,

, l _1i is the distance between the one peripheral target and the remaining peripheral target received by the mobile from the USN tag.

(여기서, R_antenna1 은 제1 안테나로 측정된 상기 하나 이상의 주변 타겟의 무선신호의 크기, R_antenna2 은 제2 안테나로 측정된 상기 하나 이상의 주변 타겟의 무선신호의 크기)이다.In addition, in the method for recognizing a location of a plurality of objects including a USN-tagged main target and one or more peripheral targets based on wireless communication, the step of measuring the location of the one or more peripheral targets may include: The position of one or more peripheral targets is determined by a position in an approximate direction measured by the antenna, from among two positions measured by the triangulation, the antenna having first and second antennas coupled at right angles to each other. The approximate direction is

Where R _antenna1 is the magnitude of the radio signal of the at least one peripheral target measured with the first antenna, and R _antenna2 is the magnitude of the radio signal of the at least one peripheral target measured with the second antenna.

In addition, according to the present invention, a method for recognizing a location of a plurality of objects including a USN-tagged main target and one or more peripheral targets based on wireless communication may include: And dividing the difference between the position and the position of the one peripheral target recalculated by the MMSE algorithm by a predetermined error to obtain the accuracy of the position of the one peripheral target.

According to the present invention, a method for recognizing a location of a plurality of objects including a USN-tagged main target and one or more peripheral targets based on a wireless communication may include a distance between a moving object and a position before and after the movement of the moving object. Measuring a first position of the main target by performing triangulation using respective distances to a target, wherein a moving direction of the movable body and a direction connecting the position after the movement of the movable body and the position of the main target are formed to each other; Measuring a second position of the main target by using an angle between the main target and an angle between the main target and a position after the movement of the movable body, and averaging the first position and the second position to determine the position of the main target. And estimating, wherein the moving object has an antenna for receiving a radio signal from the USN tag.

In addition, according to the present invention, a method for recognizing a location of a plurality of objects including a USN-tagged main target and one or more peripheral targets based on a wireless communication, pre-set the difference between the first location and the second location Dividing by an error to obtain an accuracy of the estimated position of the main target.

According to the present invention, a system for recognizing a location of a plurality of objects including a USN-tagged main target and one or more peripheral targets based on a wireless communication includes: a moving object having an antenna for rotating and receiving a radio signal from the plurality of objects. And a location determiner configured to perform the method for recognizing a plurality of objects based on wireless communication according to any one of claims 1 to 6.

In addition, according to the present invention, a system for recognizing a location of a plurality of objects including a USN-tagged main target and one or more peripheral targets on a wireless communication basis, the antennas are first and second antennas coupled at right angles to each other It is provided.

According to the present invention having the above-described configuration, a plurality of targets can be relatively positioned around the current position of the moving object by using the position information between the movements of the moving object that is actively monitored without using a base station that already knows the position. You can monitor your location.

In addition, the present invention effectively monitors a plurality of people and equipment entering and exiting the workplace in an environment where it is difficult to install a base station, such as a large space for operating the PET radiopharmaceutical automatic synthesizing device or a large number of moving objects, etc. It can contribute to ensuring the safety of the workplace.

In addition, since the direction of one target can be accurately measured when the two-axis antenna is moved, and only the other direction can be measured, the conventional problem of monitoring the position of only one target can be solved.

In addition, the present invention can monitor the position of the surrounding target (peripheral tag) other than the target while the moving object moves to the target by using the USN tag that can measure the distance.

1 shows a biaxial antenna according to the invention.
2 is a view for explaining a method for measuring the position of the main target according to the present invention.
3 is a diagram showing that the positions of the peripheral targets appear at both sides during triangulation.
4 is a view for explaining a method of measuring the position of the peripheral target according to the present invention.

Hereinafter, an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

First, a two-axis antenna applied to the present invention will be described with reference to FIG.

As shown in FIG. 1, the two-axis antenna may be two loop antennas (a first antenna and a second antenna) coupled to each other at right angles. As will be described later, the two-axis antenna can effectively present the direction of movement when the moving object moves to the target, and also, when triangulating using only the distance value, the object is divided into two positions, which is useful for determining one position. Can be utilized.

A USN tag (Ubiquitous Sensor Network Tag) may be attached to the target to be measured position, and the direction measurement of the target may be measured by using the difference in the size of the radio waves measured by the two antennas.

In theory, the angle θ of the incoming radio wave at the antenna is

[Equation 1]

Although the measurement is possible, in practice, since there is an offset value, the direction in which the propagation intensity measured by the first antenna and the propagation intensity measured by the second antenna are equal to each other while the antenna is rotated is estimated as the direction of arrival of the radio wave. In other words, the direction is determined by the ratio of the magnitudes of the signals received from the two antennas as shown in [Equation 1], but in reality there are noises and offsets from the device, so the exact direction of propagation even when calculated according to [Equation 1] This is not calculated.

Therefore, when passing through the center direction between the two antennas, the measured values measured by the two antennas are equal, and the rotating motor is mounted below the two antennas in consideration of the relatively small influence of the offset or noise. The antenna is rotated so that the antenna direction is determined as the direction of the target when the ratio of the magnitude of radio waves from the target becomes 1, that is, when the strengths of the radio waves measured by the two antennas are the same.

When there are a plurality of targets, since the direction of all targets cannot be tracked with one biaxial antenna, only the direction of one target is measured during the rotation of the antenna, and the remaining target directions are obtained by using the ratio of the magnitude of the radio wave. Set an 'approximate direction'. That is, the closer the ratio of the magnitude of the radio wave to 1 is, the closer to the center direction of the two antennas, and the closer the distance is to the right angle direction of each antenna. Here, the "approximate direction" refers to a direction in which an offset, noise, or the like is reflected, such as the direction of the target determined by [Equation 1].

Hereinafter, a method of tracking the position of the target target will be described with reference to FIG. 2.

The location tracking of the main target 2 is tracked using the direction and distance. Here, for example, a USN tag (Ubiquitous Sensor Network Tag) is attached to the main target 2, and the mobile unit 1 includes the above-described two-axis antenna and receives a radio signal from the USN tag to receive the main target 2. It is a system that can recognize location. Here, the position determination unit (not shown) for determining the position of the main target 2 by receiving a signal from the biaxial antenna mounted on the movable body 1 is provided integrally with the movable body 1, or the movable body 1 It may be provided separately from.

First, the distance d between the positions Pt. 1 and Pt. 2 before and after the movement of the movable body 1, and the distance l _t ¹ from the position before and after the movement to the main target 2. Use _t ² ) to triangulate to find the position of the main target (2). Next, the position of the main target 2 is calculated by using θ ₁ and l _t ² at the position Pt. 2 after the movement of the movable body 1. The two positions are averaged and estimated as the positions of the main targets 2.

By the difference between these two positions, the accuracy of the estimated position of the main target 2 can be obtained by dividing the predetermined or desired error (for example, 1m if the error is to be estimated to be 1m, 50cm if the weight is to be estimated to be 50cm, etc.). have.

Hereinafter, a method of tracking the position of the peripheral target 3 will be described with reference to FIGS. 3 and 4.

First, the position of the peripheral target 3 is the distance d between the movement front and back positions Pt.1 and Pt.2 of the movable body 1, and the position before and after movement of the movable body 1 (Pt.1, Pt. 2) the distance value (l ₁ ¹ ,) from each to the surrounding target (3); Triangulate using l ₁ ² ).

At this time, as a result of the triangulation, the position of the peripheral target 3 appears on the left and right around the moving direction of the movable body 1, but the position of the peripheral target 3 in the estimated direction from the two-axis antenna mounted on the movable body 1 The position of the target 3 is determined. That is, as shown in FIG. 3, the position of the peripheral target 3 appears on both sides of the moving direction of the moving object 1 during triangulation, where the peripheral target 3 is formed by using a biaxial antenna mounted to the moving object 1. Since the 'approximate' direction is measured, the position in that direction is determined as the position of the peripheral target 3.

Then, with the measured position of the peripheral target 3, the position of the peripheral target 3 is recalculated using a minimum mean squared error (MMSE) algorithm.

For example, referring to FIG. 4, the position of the peripheral target Trasponder ₁ and 3 is referred to as (x ₁ , y ₁ ) and the position of the other peripheral target Trasponder _i and _i is referred to as (x _i , y _i ). In this case, the distance between the peripheral target 3 and another peripheral target i is

&Quot; (2) "

Is calculated.

At this time, the distance between the peripheral target (3) and the other peripheral target (i) (USN tag attached to the main target and the peripheral target is capable of bi-directional communication, moving only the distance from the moving target to the main target and the peripheral target In addition, the distance between the main target and the surrounding target can also be received) l _1i

The difference between the distance calculated by Equation 2 and the distance l _1i received by the moving object is

&Quot; (3) "

를 최소로 만드는 값Is represented, where

Value that minimizes

&Quot; (4) "

This is the position of the desired peripheral target 3.

If necessary, the calculations are repeated in the same order to recalculate the positions of all peripheral targets (e.g., n). It is also possible to repeat the same steps in order to increase the accuracy of the position of the peripheral target 3. The accuracy of each position includes the distance d between the positions before and after the movement of the movable body 1, and the movable body 1 and the peripheral target 3 at the respective positions Pt.1 and Pt.2 before and after the movement. The difference between the position of the peripheral target 3 measured by triangulation using the measurement distance therebetween and the position of the peripheral target 3 calculated by the above-described MMSE algorithm is determined in advance or by dividing the desired error. 100%).

As described above, the core of the present invention is to obtain the position of the peripheral target by triangulation using the distance between the movement of the moving object and the measured distance value between the moving object and the peripheral target at each position before and after the movement, The concept of filtering using the MMSE algorithm.

While the present invention has been particularly shown and described with reference to exemplary embodiments, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, but, on the contrary, And all changes and modifications to the scope of the invention.

1. moving object, 2. main target
3. peripheral target, i. Other nearby targets

Claims (8)

A method for recognizing a location of a plurality of objects including a USN tagged main target and one or more peripheral targets based on a wireless communication,
Measuring the position of the one or more peripheral targets by performing triangulation using the distance traveled by the moving body and each distance from the position before and after the movement of the movable body to the one or more peripheral targets;
The position of any one of the one or more neighboring targets and the position of the other one of the one or more neighboring targets measured are measured using a minimum mean squared error (MMSE) algorithm. Recalculate Location
Including;
The mobile unit includes an antenna for receiving a radio signal from the USN tag.
Wireless communication based multiple object location recognition method. In claim 1,
The recalculated position of any one peripheral target is

Here, the position of any one peripheral target is (x ₁ , y ₁ ), the position of the remaining peripheral target is (x _i , y _i ), and the distance between the one peripheral target and the remaining peripheral target is

,

, l _1i is the distance between the one peripheral target and the remaining peripheral target received by the mobile from the USN tag)
Wireless communication-based multi-object location recognition method. In claim 1,
In measuring the position of the one or more peripheral targets,
The position of the at least one peripheral target is set to a position in an approximate direction measured by the antenna, from two positions measured by the triangulation,
The antenna has a first antenna and a second antenna coupled to each other at right angles,
The approximate direction is

Where R _antenna1 is the magnitude of the radio signal of the at least one peripheral target measured with the first antenna, and R _antenna2 is the magnitude of the radio signal of the at least one peripheral target measured with the second antenna.
Wireless communication based multiple object location recognition method. In claim 1,
The difference between the position of the one peripheral target measured by the triangulation and the position of the one peripheral target recalculated by the MMSE algorithm is divided by a predetermined error to determine the position of the position of the one peripheral target. A method of recognizing a plurality of objects based on wireless communication further comprising the step of obtaining an accuracy. A method for recognizing a location of a plurality of objects including a USN tagged main target and one or more peripheral targets based on a wireless communication,
Measuring a first position of the main target by performing triangulation using a distance traveled by the moving object and a distance from a position before and after the movement of the moving object to the main target,
The first target of the main target is formed by using an angle formed by the moving direction of the movable body, the position after the movement of the movable body, and the direction connecting the position of the main target to each other, and the distance between the main target at the position after the movement of the movable body. 2 measuring positions,
Estimating the position of the main target by averaging the first position and the second position;
Including;
The mobile unit includes an antenna for receiving a radio signal from the USN tag.
Wireless communication based multiple object location recognition method. The method of claim 5,
And dividing the difference between the first position and the second position by a predetermined error to obtain an accuracy of the estimated position of the main target. A system for recognizing a location of a plurality of objects including a USN tagged main target and one or more peripheral targets based on a wireless communication,
A mobile body having an antenna for rotating and receiving a radio signal from the plurality of objects,
Position determination unit for performing a method for recognizing a plurality of objects based on the wireless communication according to any one of claims 1 to 6.
Wireless communication-based multiple object location recognition system comprising a. In claim 7,
And said antenna comprises first and second antennas coupled at right angles to each other.

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