KR101831199B1 - A method for precise position determination using RSSI and DOP information of wireless network - Google Patents

Abstract

(A) selecting a first group of base stations based on a predetermined criterion among a plurality of base stations and transmitting the position information of the first group base station and a received signal strength indicator (RSSI) Calculating a comparison position of the receiving terminal based on the comparison result; (b) calculating first placement information (Dution of Precision) based on a comparison position of the receiving terminal and position information of the first group base station; (c) selecting a second group of base stations based on a predetermined criterion among the plurality of base stations, and based on the comparison position of the receiving terminal and the position information of the second group base station, of Precision); And (d) based on the signal strengths of the first group and the second group base station, the first placement information, and the second placement information, one of the first group and the second group is positioned at a position Selecting a reference base station for measurement and calculating a position of the receiving terminal based on the position information and the signal strength of the selected reference base station.

Description

[0001] The present invention relates to a method of precise positioning using RSSI and DOP (Dilution of Precision) information of a wireless network,

The present invention relates to a network-based, high-precision positioning method.

A positioning method using a received signal strength indicator (RSSI) of a conventional wireless network is a method in which a receiving terminal (hereinafter referred to as a terminal) located in an area in which a plurality of (usually three or more) base station signals are receivable receives an RSSI attenuation model (Base station position information and calculated distance information), which are sequentially transmitted from the base station to the mobile station, and then sequentially triangulated using the base station information (the distance information is physically close to the base station) As shown in FIG.

Alternatively, if the signal strength information measured by the receiving terminal is transmitted as a Positioning Determination Entity (PDE), the PDE determines the position of the corresponding terminal by triangulation using the base station information for transmitting the signal to the corresponding terminal, And transmitting the calculated position information.

The positioning accuracy of this conventional method is proportional to the accuracy of the distance information calculated using the attenuation model for RSSI measurements. For example, under propagation environments where multipaths are large, such as indoors, conventional RSSI attenuation models exhibit large distance calculation errors. Because of the distance error of several meters even under the normal radio wave environment, the triangular surveyed position error is maintained over several meters.

Therefore, there is a need for a highly accurate network-based positioning method capable of stably providing the position accuracy within 3 m required for the user's location in the indoor environment composed of the corridor and the dividing section.

The present invention is directed to solving the above-mentioned problems and other problems. Another object of the present invention is to provide a highly accurate positioning method that further considers the comparison arrangement information of the base stations related to the positioning in the triangulation method using RSSI.

According to an aspect of the present invention, there is provided an apparatus for selecting a first group of base stations based on a predetermined criterion among a plurality of base stations, Calculating a comparison position of a receiving terminal based on RSSI (Received Signal Strength Indicator); (b) calculating first placement information (Dution of Precision) based on a comparison position of the receiving terminal and position information of the first group base station; (c) selecting a second group of base stations based on a predetermined criterion among the plurality of base stations, and based on the comparison position of the receiving terminal and the position information of the second group base station, of Precision); And (d) based on the signal strengths of the first group and the second group base station, the first placement information, and the second placement information, one of the first group and the second group is positioned at a position And determining a position of the receiving terminal based on the position information and the signal strength of the selected reference base station.

In the embodiment, the step (a) may include: selecting a first base station, a second base station, and a third base station as the first group according to the order of the signal strengths of the plurality of base stations .

In yet another embodiment, the step (a) comprises applying a triangulation based on the position information of the first base station, the second base station and the third base station and the signal strength, And calculating a comparison position.

In another embodiment, the step (c) includes: selecting the fourth base station having a large signal strength next to the first base station, the second base station and the third base station as the second group can do.

In yet another embodiment, the step (d) may include: determining, based on the signal strengths of the first base station, the second base station, and the third base station, And calculating a second selection indicator for the second group based on the signal strengths of the first base station, the second base station and the fourth base station and the second placement information .

In another embodiment, the step (d) may include the step of selecting a group of smaller values among the first selection index and the second selection index as the reference base station.

In another embodiment, the step (d) may include calculating a position of the receiving terminal by applying a triangulation based on the position information and the signal strength of the reference base station.

The effect of the high accuracy positioning method using the received signal strength indicator (RSSI) and the dilution of precision (DOP) information of the wireless network according to the present invention will be described below.

The positioning method using the existing wireless network signal strength gives low accuracy position information under a poor propagation environment such as a multi-path environment, but according to the present invention, it is possible to make more precise positioning even under the same environment. As a result, the stability and usability of the location information can be dramatically improved.

Further scope of applicability of the present invention will become apparent from the following detailed description. It should be understood, however, that the detailed description and specific examples, such as the preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art.

1 is a flowchart for explaining a highly accurate positioning method according to the present invention.
2 is a conceptual diagram for explaining a triangulation method using RSSI.
3 is a flowchart for explaining an embodiment in which a reference base station is selected.
4 is a conceptual diagram for explaining an embodiment in which a reference base station is selected.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to the like elements throughout. The suffix "module" and " part "for the components used in the following description are given or mixed in consideration of ease of specification, and do not have their own meaning or role. In the following description of the embodiments of the present invention, a detailed description of related arts will be omitted when it is determined that the gist of the embodiments disclosed herein may be blurred. It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are intended to provide further explanation of the invention as claimed. , ≪ / RTI > equivalents, and alternatives.

Terms including ordinals, such as first, second, etc., may be used to describe various elements, but the elements are not limited to these terms. The terms are used only for the purpose of distinguishing one component from another.

It is to be understood that when an element is referred to as being "connected" or "connected" to another element, it may be directly connected or connected to the other element, . On the other hand, when an element is referred to as being "directly connected" or "directly connected" to another element, it should be understood that there are no other elements in between.

The singular expressions include plural expressions unless the context clearly dictates otherwise.

In the present application, the terms "comprises", "having", and the like are used to specify that a feature, a number, a step, an operation, an element, a component, But do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, or combinations thereof.

The present invention relates to a method for enabling high precision positioning by further considering the comparison arrangement information of a base station associated with positioning in a triangulation method using RSSI.

1 is a flowchart for explaining a highly accurate positioning method according to the present invention.

Referring to FIG. 1, a base station of a first group is selected based on a preset reference among a plurality of base stations, and based on position information of a first group base station and a received signal strength indicator (RSSI) (S110) of calculating the comparison position of the receiving terminal is proceeded.

Subsequently, step S120 of calculating the first placement information (DOP: Dilution of Precision) is performed based on the comparison position of the receiving terminal and the position information of the first group base station.

Next, based on a predetermined criterion among the plurality of base stations, a second group of base stations is selected, and based on the comparison position of the receiving terminal and the position information of the second group base station, Dilution of Precision (S130) is performed.

Thereafter, based on the signal strengths of the first group and the second group base station, the first placement information, and the second placement information, one of the first group and the second group is subjected to position measurement (S140) of calculating the position of the receiving terminal based on the position information and the signal strength of the selected reference base station.

In an exemplary embodiment, the step S110 may include selecting the first base station, the second base station, and the third base station as the first group in order of increasing signal strength among the plurality of base stations.

In yet another embodiment, the step S110 may include applying a triangulation based on the location information of the first base station, the second base station, and the third base station and the signal strength, And a step of calculating

In yet another embodiment, the step S130 may include selecting a fourth base station having a large signal strength next to the first base station, the second base station, and the third base station as the second group .

In yet another embodiment, the step of S140 may further include the step of, based on the signal strengths of the first base station, the second base station and the third base station, and the first placement information, And calculating a second selection index for the second group based on the signal strengths of the first base station, the second base station, and the fourth base station and the second placement information.

In yet another embodiment, the step S140 may include selecting a group of smaller values among the first selection index and the second selection index as the reference base station.

In yet another embodiment, the step S140 may include calculating a position of the receiving terminal by applying a triangulation based on the position information of the reference base station and the signal strength.

In the present invention, the receiving terminal may be a mobile phone, a smart phone, a laptop computer, a digital broadcasting terminal, a personal digital assistant (PDA), a portable multimedia player (PMP), a navigation device, a slate PC ), Tablet PCs, ultrabooks, wearable devices (e.g., smartwatches, smart glass, HMDs (head mounted displays), etc.) Terminal.

However, it will be appreciated by those skilled in the art that the configuration according to the embodiments described herein may be applied to fixed terminals such as a digital TV, a desktop computer, a digital signage, and the like, will be.

2 is a conceptual diagram for explaining a triangulation method using RSSI.

) 순서로 상위 세 개의 네트워크 기지국을 선정한다. Referring to FIG. 2, the signal strength of a plurality of base stations is high (RSSI is large,

), The top three network base stations are selected.

In an embodiment, the first base station, the second base station, and the third base station may be selected as the first group of base stations in order of increasing signal strength.

)를 이용해 일반적인 삼각측량 방법으로 수신단말의 비교 위치(

)를 결정한다. Then, the three network base station information having a strong signal strength

) Using the general triangulation method to compare the location of the receiving terminal (

).

The comparison placement information (DOP) is calculated using the following procedure using the comparison position of the receiving terminal determined in this manner and the position information of the base station (base station associated with the comparison position determination). At this time, the comparison arrangement information means the first arrangement information.

First, the unit vector from the receiving terminal to the i-th base station can be calculated as Equation (1).

)는 수신단말의 비교위치를 의미하고, (

)는 i 번째 기지국 위치를 의미한다. here, (

) Denotes a comparison position of the receiving terminal, and

) Denotes an i-th base station position.

Next, the line-of-sight matrix A composed of unit vectors to the i-th base station can be calculated by the following equation (2).

Then, the mutual covariance matrix Q can be calculated by the following Equation (3).

Based on the calculated values, the comparison arrangement information DOP can be calculated by the following equation (4).

를 4번째 크기의 RSSI를 주는 기지국 정보

로 대체하여, 후보 배치정보(DOP1, 2, n)를 재계산할 수 있다. Next, the base station information providing the RSSI information of the third size

To the base station information providing the RSSI of the fourth size

, The candidate arrangement information DOP1, 2, n can be recalculated.

As an example, the third base station may be replaced by a fourth base station having a signal strength next to the third base station. Accordingly, the first base station, the second base station, and the fourth base station can be selected as the base stations of the second group. Then, candidate placement information (second placement information) can be calculated.

The gaze angle matrix A1,2, n and the mutual covariance matrix Q1,2, n for calculating the candidate placement information can be calculated by the following equation (5).

As a result, the candidate placement information can be calculated by the following equation (6).

Next, the RSSI information for each base station associated with the positioning, the previously calculated comparison placement information (first placement information), and the candidate placement information (second placement information) are set as the input terms of the base station selection algorithm, 1 selection index) and candidate selection index (second selection index).

At this time, the selection index can be calculated by the following equation (7).

Based on Equation (7), the comparison selection indicator and the candidate selection indicator can be calculated by the following Equation (8).

Next, the comparison selection index is compared with the candidate selection index, and a combination of base stations indicating a small selection index is selected as the positioning reference base station.

The reference base station can be calculated by the following equation (9).

3 is a flowchart for explaining an embodiment in which a reference base station is selected.

Referring to FIG. 3, RSSI and DOP values may be input as input values of a BS selection algorithm. Accordingly, the RSSI index value and the DOP index value are calculated, and the base station selection index can be calculated based on the RSSI index value and the DOP index value. The reference base station is selected based on the calculated base station selection index.

In an embodiment, when the RSSI value and the DOP value of the first base station, the second base station, and the third base station are input, the index value for each value can be calculated by Equation (7). Then, the value of the comparison selection indicator (first selection indicator) can be calculated by Expression (8).

Similarly, when the RSSI value and the DOP value of the first base station, the second base station, and the nth base station are input, the index value for each value can be calculated by Equation (7). Then, the value of the candidate selection index (the second selection index or the n-th selection index) can be calculated by the equation (8).

The size of the comparison selection index thus calculated and the size of the candidate selection index are compared to select the reference base station.

4 is a conceptual diagram for explaining an embodiment in which a reference base station is selected.

4, when the first selection index (comparison selection index) is smaller than the second selection index (candidate selection index), the first base station, the second base station and the third base station can be selected as the reference base station A have.

Alternatively, when the first selection index (comparison selection index) is larger than the second selection index (candidate selection index), the first base station, the second base station, and the fourth base station can be selected as the reference base station B.

Thereafter, triangulation is performed using the selected reference base station (positioning reference base station), and the position of the receiving terminal is determined. In this case, the accuracy of the calculated position can be improved to some extent.

The effect of the high accuracy positioning method using the received signal strength indicator (RSSI) and the dilution of precision (DOP) information of the wireless network according to the present invention will be described below.

The positioning method using the existing wireless network signal strength gives low accuracy position information under a poor propagation environment such as a multi-path environment, but according to the present invention, it is possible to make more precise positioning even under the same environment. As a result, the stability and usability of the location information can be dramatically improved.

The present invention described above can be embodied as computer-readable codes on a medium on which a program is recorded. The computer readable medium includes all kinds of recording devices in which data that can be read by a computer system is stored. Examples of the computer readable medium include a hard disk drive (HDD), a solid state disk (SSD), a silicon disk drive (SDD), a ROM, a RAM, a CD-ROM, a magnetic tape, a floppy disk, , And may also be implemented in the form of a carrier wave (e.g., transmission over the Internet). Also, the computer may include a control unit 180 of the terminal. Accordingly, the above description should not be construed in a limiting sense in all respects and should be considered illustrative. The scope of the present invention should be determined by rational interpretation of the appended claims, and all changes within the scope of equivalents of the present invention are included in the scope of the present invention.

Claims (7)

(a) selecting a first group of base stations based on a preset reference among a plurality of base stations, and selecting a comparison position of a receiving terminal based on position information of the first group base station and a received signal strength indicator (RSSI) ;
(b) calculating first placement information (Dution of Precision) based on a comparison position of the receiving terminal and position information of the first group base station;
(c) selecting a second group of base stations based on a predetermined criterion among the plurality of base stations, and based on the comparison position of the receiving terminal and the position information of the second group base station, of Precision); And
(d) based on the signal strengths of the first group and the second group base station, the first placement information, and the second placement information, one of the first group and the second group is measured And calculating a position of the receiving terminal based on the position information and the signal strength of the selected reference base station. The method according to claim 1,
The step (a)
And selecting the first base station, the second base station, and the third base station as the first group according to the order of the signal strengths of the plurality of base stations. 3. The method of claim 2,
The step (a)
And calculating a comparison position of the receiving terminal by applying a triangulation based on the position information and the signal strength of the first base station, the second base station, and the third base station, High precision positioning method. The method of claim 3,
The step (c)
And selecting a fourth base station having a large signal strength next to the first base station, the second base station and the third base station as the second group. 5. The method of claim 4,
The step (d)
Calculates a first selection index for the first group based on the signal strengths of the first base station, the second base station and the third base station and the first placement information,
And calculating a second selection index for the second group based on the signal strengths of the first base station, the second base station and the fourth base station and the second placement information Positioning method. 6. The method of claim 5,
The step (d)
And selecting a group for a smaller value among the first selection index and the second selection index as the reference base station. The method according to claim 6,
The step (d)
And calculating a position of the receiving terminal by applying a triangulation based on the position information and the signal strength of the reference base station.

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