KR20230063241A - A Positioning System and Method thereof using Signal Strength, Distance and Azimuth - Google Patents

Abstract

The present invention relates to a positioning system and a method thereof. In the positioning system, a plurality of receivers receive a wireless signal transmitted from a wireless signal transmitting device, the received wireless signal is transmitted to a server, and the server measures the position of the wireless signal transmitting device. Then, unit positions are calculated based on the signal strength of the receiver which receives the wireless signal from the transmitter. And, by adding the distance and azimuth to the transmitter to determine the final unit position with increased accuracy by combining the unit positions, and selecting the final position, the reliability of position measurement can be increased.

Description

A Positioning System and Method Using Signal Strength, Distance and Azimuth

In the present invention, a plurality of receivers receive radio signals transmitted from a radio signal transmission device, the received radio signals are transmitted to a server, the server measures the location of the radio signal transmission device, and then the receiver receives the radio signal of the transmitter. A positioning system and method that can increase the reliability of position measurement by calculating the unit position with the signal strength, determining the final unit position with increased accuracy of the unit position by adding the distance and azimuth to the transmitter, and selecting the final position by combining them it's about

Attempts have been made to provide various services such as preventing and finding lost children by attaching a wireless signal transmission device (hereinafter referred to as a 'transmitter') to a person or object and tracking the location of a person or object, and tracking the location of logistics during movement. In this attempt, a separate receiving device (hereinafter referred to as 'receiver') receives a wireless signal transmitted from a transmitter that transmits wireless signals such as BLE (Bluetooth Low Energy) beacon, Wi-Fi, Bluetooth, ZigBee, and UWB to receive the signal It is done by measuring the position of the emitter based on the intensity.

So far, the method of measuring the location has been used triangulation / trilateration and wireless fingerprint method. However, the radio signal transmitted from the transmitter is unstable to the extent that its value changes every moment even at the same point due to numerous factors such as other radio waves, temperature, humidity, objects, and people. Therefore, when the position is measured based on the unstable radio signal, even if the terminal is at the same point, the radio signal of the transmitter received by the receiver changes every moment, so it appears as if the position of the transmitter has changed. This reliability problem can be said to be a serious drawback in attempts to measure the position of a transmitter using a radio signal so far. Therefore, a process of normalizing an unstable wireless signal into a reliable and stable wireless signal is absolutely necessary, and the present invention started in this context.

[Prior patent literature]

Republic of Korea Patent Publication No. 10-2014-0119333 "Position positioning method and device for improving position accuracy"

It was devised to solve the problems of the prior art,

An object of the present invention is to select a predetermined number of receivers in the order of signal strength among receivers receiving radio signals from transmitters, and to select a unit position between the remaining receivers based on the receiver showing the strongest radio signal strength among the radio signals of these receivers. It is to provide a positioning system and method capable of increasing the reliability of position measurement by calculating and selecting the final position by integrating these multiple unit positions.

Another object of the present invention, the position measuring unit further comprises a final unit position calculation unit for determining a final unit position by additionally calculating the distance and azimuth angle of the transmitter and the receiver with respect to the first unit position, the final unit The position calculation unit calculates the second unit position determination module for determining the second unit position of the transmitter based on the distance and azimuth angle between the transmitter and the receiver measured by the receiver, and calculates the second unit position with the first unit position determined by the unit position calculator and a final unit position determination module for determining the final unit position, wherein the final position determination unit calculates a plurality of final unit positions to determine the final position of the emitter, thereby reducing errors caused by measured values of different characteristics. An object of the present invention is to provide a positioning system and method for measuring a more accurate position.

Another object of the present invention is that the final unit position determination module determines the final unit position closer to the unit position where the width of the area connecting each unit position is smaller among the first unit position and the second unit position measured for each receiver. And the final unit position is weighted and calculated in inverse proportion to the ratio of the square root of the area formed by the plurality of first unit positions and the second unit position, thereby measuring the position of the emitter based on the more accurate unit position An object of the present invention is to provide a positioning system and method with improved positioning accuracy.

Another object of the present invention is to calculate the final unit position of each receiver by calculating the second unit position of the strongest receiver with the first unit position of the strongest receiver and the first unit position of the strongest receiver, so that the final unit position determination module calculates the speed of position measurement. It is to provide a positioning system and method capable of quickly

Another object of the present invention is to calculate the distance between the receiver that has received the current radio signal and the previous position of the transmitter, and if it is greater than a predetermined distance threshold, the receiver is excluded from the position measurement process of the transmitter to measure the reliability of the position. It is to provide a positioning system and method capable of increasing the

Another object of the present invention, if the difference between the radio signal strength of the receiver receiving the strongest radio signal and the remaining receivers is more than a predetermined signal strength threshold value, the transmitter is located adjacent to the receiver receiving the strongest radio signal It is to provide a positioning system and method capable of increasing the reliability of position measurement by determining that the position is determined as such.

Another object of the present invention is a positioning system and method for increasing accuracy by adding the distance and azimuth of the transmitter to the position measurement process using the existing wireless signal strength by using the distance and azimuth of the transmitter coming through the AoA receiver. is to provide

The present invention is implemented by the following embodiments in order to achieve the above object.

According to an embodiment of the present invention, the positioning system of the present invention includes a plurality of receivers that receive radio signals transmitted from transmitters, and a server that receives radio signal information from the plurality of receivers, wherein the server is located A receiver list determination unit that defines the number of receivers to participate in the decision, and a final determination of the position of the transmitter based on the signal strength or signal strength of each receiver's radio signal on the list of receivers determined by the receiver list determination unit, distance and azimuth angle It is characterized in that it comprises a positioning unit having a positioning unit.

According to another embodiment of the present invention, in the positioning system of the present invention, the receiver list determining unit arranges the receiver list in the order of receivers showing strong signal strength within a predetermined number of ranges, and the position measuring unit arranges the strongest receiver and the strongest receiver and the strongest receiver. Based on the signal strength of the strongest receiver and at least one or more chagang receiver including a unit position calculation unit for calculating the first unit position of the emitter, wherein the first unit position is defined on a straight line between the strongest receiver and the chagang receiver to be characterized

According to another embodiment of the present invention, in the positioning system of the present invention, the position measurement unit additionally calculates the distance and azimuth of the transmitter and the receiver with respect to the first unit position, and determines the final unit position. The final unit position calculation unit further includes a second unit position determination module for determining the second unit position of the transmitter based on the distance and azimuth angle between the transmitter and the receiver measured from the receiver, and the second unit position of the unit position calculator And a final unit position determination module for determining the final unit position by calculating the first unit position determined in, and the final position determining unit calculates a plurality of final unit positions to determine the final position of the emitter.

According to another embodiment of the present invention, in the positioning system of the present invention, the final unit position determination module determines the final unit position by averaging the first unit position and the second unit position measured for each receiver. do.

According to another embodiment of the present invention, in the positioning system of the present invention, in the final unit position determination module, the width of an area connecting each unit position among the first unit position and the second unit position measured for each receiver is smaller. It is characterized in that the final unit position is determined close to the unit position.

According to another embodiment of the present invention, in the positioning system of the present invention, the final unit position is weighted and calculated in inverse proportion to the ratio of the square root of the area formed by the plurality of first unit positions and second unit positions to be characterized

According to another embodiment of the present invention, in the positioning system of the present invention, the final unit position determination module calculates the second unit position of the strongest receiver with the first unit position of the strongest receiver and the strongest receiver and the final unit position of each receiver It is characterized in that it calculates.

According to another embodiment of the present invention, in the positioning system of the present invention, the receiver list determination unit sorts the receiver list in the order of receivers showing strong signal strength within a predetermined number of ranges, and the position measurement unit sorts the strongest of the receiver list. If the signal strength difference between the receiver and the chagang receiver is more than a predetermined signal strength threshold value, it is characterized in that it further comprises a neighbor determination unit for determining that the emitter is adjacent to the strongest receiver.

According to another embodiment of the present invention, in the positioning system of the present invention, the receiver list determination unit calculates the distance between the receiver currently transmitting the radio signal and the previous position of the transmitter, and if it is greater than the distance threshold, the receiver is selected as the receiver. It is characterized in that the error of position measurement is reduced by excluding it from the list.

The present invention has the following effects by the above configuration.

The present invention calculates the unit position with the signal strength of the receiver receiving the radio signal of the transmitter, adds the distance and azimuth to the transmitter to determine the final unit position with increased accuracy of the unit position, and selects the final position by synthesizing the location. The effect of increasing the reliability of measurement can be obtained.

In the present invention, the position measuring unit further includes a final unit position calculating unit for determining a final unit position by additionally calculating a distance and an azimuth angle between the transmitter and the receiver with respect to the first unit position, and the final unit position calculating unit includes a receiver A second unit position determination module for determining the second unit position of the transmitter based on the distance and azimuth of the transmitter and receiver measured from the transmitter, and the final unit position by calculating the second unit position with the first unit position determined by the unit position calculator And a final unit position determination module for determining the final position, wherein the final position determination unit calculates a plurality of final unit positions to determine the final position of the emitter, thereby reducing errors caused by measurement values of different characteristics to obtain a more accurate position. make it measurable.

In the present invention, the final unit position determination module determines the final unit position closer to the unit position where the width of the area connecting each unit position is smaller among the first unit position and the second unit position measured for each receiver, The final unit position is weighted and calculated in inverse proportion to the ratio of the square root of the area formed by the plurality of first unit positions and the second unit position, thereby measuring the position of the transmitter based on the more accurate unit position to achieve position measurement accuracy has the effect of enhancing

In the present invention, the final unit position determination module calculates the second unit position of the strongest receiver with the first unit position of the strongest receiver and car receivers to calculate the final unit position of each receiver, thereby speeding up the position measurement. there is.

The present invention calculates the distance between the receiver that has received the current radio signal and the previous position of the transmitter, and if it is greater than a predetermined distance threshold, the receiver is excluded from the position measurement process of the transmitter to increase the reliability of position measurement. have an effect

The present invention determines that the transmitter is located adjacent to the receiver receiving the strongest radio signal when the difference between the radio signal strength of the receiver receiving the strongest radio signal and the other receivers is equal to or greater than a predetermined signal intensity threshold. The effect of increasing the reliability of measurement can be obtained.

1 is a diagram illustrating a positioning system and method according to an embodiment of the present invention;
Figure 2 is a block diagram of a radio signal normalization system according to an embodiment of the present invention.
3 is a block diagram of a radio signal normalization unit shown in FIG. 2;
FIG. 4 is a diagram showing a queue to which radio signal signal strength, distance, and azimuth angle are input by the radio signal normalization unit shown in FIG. 2;
5 is a block diagram of a position measuring unit shown in FIG. 2;
6 is a flowchart illustrating a radio signal normalization method and a positioning method using the same according to an embodiment of the present invention.
Figure 7 is a flow chart of the radio signal normalization step shown in Figure 6;
8 is a flowchart of the signal strength determining step shown in FIG. 7;
9 is a flowchart of the position measurement step shown in FIG. 6;
10 is a flow chart of a receiver list determination step shown in FIG. 9;
11 is a view showing a use state of a positioning method according to an embodiment of the present invention.
12 is a diagram comparing an area formed by first unit positions and an area formed by second unit positions of each receiver;
13 is a diagram showing that the transmitter 1 is located in an area formed by final unit positions.

Hereinafter, a joint and a base plate of an artificial shoulder joint according to the present invention will be described in detail with reference to the accompanying drawings. It should be noted that like elements in the drawings are indicated by like numerals wherever possible. In addition, detailed descriptions of well-known functions and configurations that may unnecessarily obscure the subject matter of the present invention will be omitted. Unless there is a special definition, all terms in this specification are the same as the general meaning of the term understood by a person skilled in the art to which the present invention belongs, and if it conflicts with the meaning of the term used in this specification, the present invention Follow the definitions used in the specification. Throughout the specification, when a part is said to "include" a certain element, this means that it does not exclude other elements unless otherwise stated, and may further include other elements, and the specification Terms such as “~unit” described herein mean a unit that processes at least one function or operation. In addition, when it is said that certain components are "connected", this is not limited to being in direct contact with each other and fastening, but includes fastening through other components, and even if they are not fastened, a predetermined force or energy can be transmitted. It can mean that it is arranged so that Terms such as "first ~" and "second ~" may be used to indicate the same or substantially the same configuration in a different order, and may be used to indicate the same or substantially the same configuration as "first" or "second". can be interpreted as composition. Hereinafter, the present invention will be described in detail by describing preferred embodiments of the present invention with reference to the accompanying drawings.

1 is a diagram illustrating a positioning system and method according to an embodiment of the present invention.

Referring to FIG. 1, the positioning system of the present invention receives a plurality of receivers (B1, B2, B3,,,,,,, Bn) for receiving radio signals transmitted from a transmitter and receives radio signals from them, signal strength, It includes a server 3 that measures the location of the transmitter by receiving radio signal information including distance, azimuth, and identification information about the receiver. Here, the server may be located at a remote or short distance from the receiver, and bidirectional or one-way communication between the server and the receiver is possible through a wired/wireless communication channel, the Internet, or the like. In addition, although the server may be configured separately from the receiver, it is not excluded that it may be provided together with any one of a plurality of receivers. After receiving the radio signal transmitted from the transmitter, the receiver measures the distance between the transmitter and the receiver and the azimuth angle of the direction in which the transmitter is located based on the receiver. At this time, the azimuth angle is expressed as an angle formed with a reference vector by projecting the direction of the transmitter perpendicular to the reference plane in the spherical coordinate system. The reference vector for azimuth measurement may be true north or magnetic north, and increases clockwise from north.

As seen above, the receiver (B1, B2, B3,,,,,,, Bn) receives a radio signal from a transmitter that transmits radio signals such as Bluetooth Low Energy (BLE) beacon, Wi-Fi, Bluetooth, ZigBee As a device, a plurality of units are arranged at regular intervals according to a predetermined design in a space where the position of the transmitter needs to be measured through interaction with the transmitter. In Figure 1, four receivers are installed at four points, and the transmitter 1 is located between the points.

The transmitter periodically transmits radio signals, for example, it can be set to transmit 2 to 4 times per second, and can be set appropriately in consideration of battery life.

The receiver (B1, B2,,,, Bn) receives the radio signal transmitted from the emitter, and must be equipped with a means capable of receiving the radio signal, and a smartphone, a beacon scanner, etc. can be exemplified. .

The server 3 includes a radio signal normalization unit 10 for normalizing the received radio signal and a position measurement unit 20 for measuring the location of the transmitter based on the normalized or non-normalized radio signal.

The wireless signal transmitted by the transmitter is so unstable that its value changes every moment even at the same point due to numerous factors such as different radio waves, temperature, humidity, objects, and people. Therefore, if the strength, distance, and azimuth of the received radio signal are used for position measurement as they are without processing, the reliability of position measurement is inevitably lowered. The radio signal normalization unit 10 serves to normalize the radio signal strength, distance and azimuth of each received receiver, and as shown in FIG. 3, the receiver 11, the signal strength determination unit 12, It includes a list management unit 15, a regular signal strength calculating unit 16, a regular distance calculating unit 17, and a regular azimuth calculating unit 18.

As shown in Figure 1, a plurality of receivers (B1, B2, B3,,,,,,, Bn) installed in the space where the transmitter (1) is located receive the radio signal transmitted by the transmitter and its strength, distance , measure the azimuth. Theoretically, it can be said that the wireless signal strength received by the receiver is greater as the receiver is closer to the transmitter (1), but as seen above, since the wireless signal is unstable due to various factors, the nearest receiver has a smaller signal strength than the farthest receiver. can also show When the location is measured based on such signal strength, it can be confirmed that the transmitter is located near the farthest receiver, not the nearest receiver. That is, in the case of FIG. 1, the receiver (B1, B2, B3,,,,,,, Bn) should measure the signal strength in the order of B1>B2>B3>B4, but due to the instability of the radio signal, the receiver receives It frequently occurs that the signal strength is measured as greater for the receiver B4 than the receiver B1, and when the location is measured based on this, the transmitter 1 can be expressed as being located close to the receiver B4. This corresponds to an error in location measurement of the terminal. For this reason, a normalization process for stably converting radio signals is required. It is preferable that the same applies to the distance and azimuth angle measured by each receiver. In the case of FIG. 1, each receiver (B1, B2, B3,,,,,,, Bn) should measure the distance in the order of B1<B2<B3<B4, but due to the instability of the radio signal as in the case of signal strength, B4 The receiver can be measured as being closer than the B1 receiver.

The signal strength determination unit 12, in consideration of the fact that the physical possible range in which the transmitter can move for a certain time is limited, considers the difference value of the signal strength of the generated wireless signal and the maximum fluctuation width C, and the current signal strength will decide For example, the distance that the emitter can move for a certain amount of time can be defined as a physical limit, and it is impossible to move beyond that physical limit for a certain amount of time.

The maximum fluctuation range C is the difference between the previous signal strength and the next signal strength of the transmitter when the transmitter moves, and means the maximum value that is physically possible and can be set by the user. For example, when the transmitter approaches from receiver B1 to B4, the radio signal strength of receiver B1 receiving the transmitter's radio signal decreases and the radio signal strength of receiver B4 receives the transmitter's radio preference increases. There is a physically possible range of fluctuations in signal strength that can occur due to the movement of (1). Fluctuations in signal strength, which means fluctuations in distances that transmitters cannot move in a short time, cause instability of wireless signals.

Subsequently, the signal strength determination unit 12 uses the current signal strength as an input signal without change when the difference value E between the previous signal strength and the current signal strength of the same receiver is smaller than the maximum fluctuation range C. This means that if the difference value E is smaller than the maximum fluctuation range C, it means that the transmitter moved within a physically possible range, so the current signal strength is used as it is. However, when the difference value E of the signal strength is larger than the maximum variation range C, the current signal strength is determined as follows.

When the difference value E of the signal strength is greater than the maximum variation range C, the signal strength determination unit 12 adds the maximum variation range C to the previous signal strength when the current signal strength of the same receiver is greater than the previous signal strength to obtain the current signal strength. If the current signal strength of the same receiver is smaller than the previous signal strength, the maximum fluctuation range C is subtracted from the previous signal strength and replaced with the current signal strength. At this time, it is preferable that the previous signal strength has a value greater than the maximum fluctuation width C.

When the list management unit 15 inputs the wireless signals determined by the signal strength determination unit to the queues Q1, Q2, Q3, and Q4 as shown in FIG. 4, and the number of input signal strengths exceeds the predetermined number The oldest signal strength is deleted. Referring to FIG. 4, the signal strength of the five radio signals transmitted from the receiver B1 is the signal strength of the five radio signals determined by the signal strength determination unit as seen above input to the cue Q1, and all of the cues Q2, Q3, and Q4 Through the same process, the radio signal strengths of the receivers B2, B3, and B4 are input. At the same time, distances are input to Q5, Q6, Q7, and Q8, and azimuths are input to Q9, Q10, Q11, and Q12, and the number of data input to the queue is determined according to the signal strength determination unit standard of the list management unit 15.

The regular signal strength calculation unit 16 averages the signal strengths filled when the queue is filled with a predetermined number, and defines it as the signal strength of the corresponding receiver. As can be seen in FIG. 4, the average value derived from reference numeral A becomes the radio signal strength, and the average value of Q1 to Q4 is used for positioning. Therefore, the signal strength, which has changed over 5 times in each receiver, is stabilized by the average value. For example, receiver B1 shows the signal strength of -54, -59, -55, -62, -60, but the average value is -58, receiver B2 average value is -64.8, transmitter B3 is -72.4, transmitter B3 becomes -82.

The regular distance calculation unit 17 averages the filled distance when the queue is filled with the predetermined number, and defines it as the distance between the corresponding receiver and transmitter. In FIG. 4 , the average value derived from reference numeral A may be defined as the distance, and the average value of Q5 to Q8 defined as the distance is used for positioning. Therefore, it is stabilized by the average value of the distances changed over 5 times in each receiver. For example, receiver B1 shows distances of 2, 2.1, 1.9, 2, 2.2, but the average is 2.04, receiver B2 is 1.92, receiver B3 is 1.88, and receiver B4 is 2.08.

The normal azimuth calculation unit 18 averages the filled azimuths when the queue is filled with the predetermined number, and defines it as the azimuth of the transmitter. As can be seen in FIG. 4, the average value of reference numeral A is defined as an azimuth, and the average value of Q9 to Q12 is used for positioning as an azimuth. Therefore, it is stabilized by the average value of the azimuth that has changed over five times in each receiver. For example, receiver B1 shows azimuths of 260, 255, 257, 264, and 262, but the average value is 259.6, receiver B2 averages 259.4, receiver B3 has 260.2, and receiver B4 has 260.6.

Hereinafter, the position measurement unit 20 according to an embodiment of the present invention will be described.

Referring to FIG. 5, the position measurement unit 20 measures the position of the transmitter 1 based on the signal strength, distance, and azimuth of the previously normalized wireless signal or the wireless signal that has not undergone the normalization process, and the receiver list. It includes a determination unit 21, an adjacent determination unit 22, a unit position operation unit 23, a final unit position operation unit 24 and a final position determination unit 25.

The receiver list determining unit 21 defines the number of receivers to participate in positioning, and arranges them in the receiver list in order of receivers showing strong signal strength within a predetermined range. Referring to FIG. 1, when four receivers are used to determine the position of a receiver, these receiver lists include information sorted in the order of B1, B2, B3, and B4. Here, the receiver showing the strongest wireless signal strength is named the strongest receiver and the remaining receivers are called chagang receivers. The number of these receivers can be changed as needed. As the number increases, the accuracy of position measurement increases, but there is a problem that the time for position measurement increases due to the increase in the amount of data. It is preferable to select

The receiver list determination unit 21 calculates the distance between the previous position of the transmitter and the receiver receiving the current radio signal of the transmitter, and if it is greater than the distance threshold value F, the corresponding receiver is excluded from the receiver list to reduce the position measurement error. Reduce. Among the receivers in the receiver list, if the distance to the previous position of the transmitter (1) is greater than the distances between the previous positions of other receivers and transmitters, the radio signal transmitted from the receiver is regarded as unstable and excluded, thereby eliminating errors in position measurement. In order to reduce, a distance threshold value F is defined, and if the distance between the previous location of the transmitter and the receiver receiving the current radio signal of the transmitter exceeds the distance threshold value F, the corresponding receiver can be deleted from the list.

The adjacency determination unit 22 determines whether the transmitter 1 is located adjacent to a predetermined receiver in a space where a plurality of receivers are installed. If the signal strength difference value R between the strongest receiver and the chagang receiver is greater than a predetermined signal strength threshold value G, the transmitter determines that it is adjacent to the strongest receiver and determines the coordinates of the strongest receiver as the position of the transmitter. For example, if the receiver is installed on the ceiling or in a high place, if the transmitter is not brought very close to the receiver, the signal strength of the wireless signal cannot be shown as much as when it is adjacent. If you do, it is determined that the transmitter is located at a predetermined point between the strongest receiver and the car receiver, but as above, if the signal strength difference value R is greater than the signal strength threshold G according to the adjacent judge is determined, so the accuracy of position measurement is increased. In this case, the operation by the unit position calculation unit below is not performed.

The unit position calculation unit 23 calculates the first unit position of the transmitter between the strongest receiver and the car receiver among the receivers in the receiver list determined by the receiver list determination unit. As seen earlier, within the receiver list, the chagang receiver refers to all receivers other than the strongest receiver, and the first unit position is the position of the transmitter on a straight line connecting the strongest receiver and the rest of the chagang receiver. As shown in FIG. 11, the coordinates of receiver B1 are P ₁ , the coordinates of receiver B2 are P ₂ , the coordinates of receiver B3 are P ₃ , the coordinates of receiver B4 are P ₄ , and the first unit position is the strongest receiver B1. Coordinates of _P1 , coordinates of transmitter _P12 on a straight line between the strongest receiver B1 and receiver B2, and coordinates of transmitter _P13 on a straight line between the strongest receiver B1 and receiver B3, and on a straight line between the strongest receiver B1 and receiver B4 It becomes the coordinates P ₁₄ of the transmitter. The first unit position may be calculated by various formulas. For example, the unit position P _1n may be determined by the following formula.

P _1n =P _n -(P _n -P ₁ ) value R/G

R: Signal strength difference between the strongest receiver and the chagang receiver

G: signal strength threshold

P _1n : first unit position of the transmitter on a straight line between the strongest receiver and the car receiver

P _n : positional coordinates of the strongest receiver P ₁ : positional coordinates of the strongest receiver

It is preferable to include the coordinates of the strongest receiver in the first unit position because it can increase the accuracy of position measurement. Also, whether or not to include the coordinates of the strongest receiver used for position measurement in the first unit position may be dependently changed according to a formula.

The final unit position calculation unit 24 determines the final unit position by additionally calculating the first unit position including the distance and azimuth between the transmitter and the receiver, and the first unit position of the transmitter determined by the unit position determination unit The accuracy of the final unit position is increased by calculating the second unit position of the transmitter determined by the distance and azimuth between the transmitter and the receiver. As described above, the first unit location is a point located on the straight lines connecting the strongest receiver and the car receiver, but in fact, the transmitter 1 is located at any one point in the area between the plurality of receivers, Even if the coordinates of one unit position are averaged, a certain degree of error may occur with the actual position of the emitter. In order to minimize the resulting error, the final unit position calculation unit 24 calculates a second unit position that may have coordinates that deviate from the straight lines connecting the strongest receiver and the car receivers through data of a different nature from the signal strength. It is possible to further reduce the error between the measured position and the position of the emitter by determining and calculating the final unit position through the second unit position and the previously derived first unit position. The final unit position calculation unit 24 includes a second unit position determination module 241 and a final unit position determination module 243.

The second unit position determination module 241 determines the second unit position of the transmitter based on the distance and azimuth between the transmitter and the receiver measured by the receiver. The second unit location may be derived from at least one of a distance and an azimuth between the transmitter and the receiver, but may be preferably calculated based on both the distance and the azimuth between the transmitter and the receiver. Preferably, the distance and azimuth angle used to determine the second unit position are the normalized distance and azimuth angle described above. As shown in FIG. 11, the distance between the receiver B2 and the position Pf of the emitter is D2, the azimuth is Z2, and the second unit position P ₂₂ can be calculated using the distance and the azimuth. The second unit position P _2n is calculated in the same way for other receivers.

The final unit position determining module 243 determines the final unit position P _3n by calculating the second unit position P 2n with the first unit position P _{1n determined} by the unit position calculating unit. The normal distance and normal azimuth from each receiver normalized in the above-described normal distance calculator 17 and normal azimuth calculator 18 represent predetermined positional coordinates. The normal distance Dn and the normal azimuth angle Zn from each receiver may not represent the same location coordinates. This is due to the instability and normalization of the radio signal, and the second unit positions (P _2n ) measured by the normal distance (Dn) and normal azimuth (Zn) measured by each receiver have a predetermined error with the actual transmitter position. . At this time, the error between the second unit position and the actual position (P _f ) of the transmitter occurs when measuring based on the measured distance and azimuth angle, and the first unit position (P _1n ) defined based on the signal strength and It is different from the error between the actual position of the emitter (P _f ) and its nature. When these errors are synthesized and smoothed, errors caused by measurement values of different characteristics can be reduced to measure more accurate positions. Therefore, a measurement error can be minimized by calculating the final unit position (P _3n ) by averaging the first unit position (P _1n ) and the second unit position (P _2n ).

In one embodiment of the present invention, the first unit position (P _1n ) and the second unit position (P _2n ) may be averaged to determine the final unit position. In a preferred embodiment of the present invention, when determining the final unit position, the final unit position ₍ P 3n ) can be derived by averaging the first unit position (P _1n ) and the second unit position (P _2n ) for each receiver. there is.

In another embodiment of the present invention, the final unit position may be calculated at a different ratio according to the area area between the first unit location P _1n and the area area between the second unit location P ₂₂ of each receiver. Referring to FIG. 12, the first unit position (P _1n ) and the second unit position (P ₂₂ ) may be calculated differently from a plurality of receivers according to the type of receiver, and the first unit position (P _1n ) between The area between the area and the second unit location P ₂₂ may also be calculated differently. When the area between the second unit locations P _2n is smaller than the area between the first unit locations P _1n , the second unit location P _2n can be estimated as a relatively accurate unit location. there is. In this case, the final unit position is not derived by averaging the first unit position (P _1n ) and the second unit position (P _2n ), but the final unit position (P _3n ) is derived close to the second unit position (P _2n ). Weights can be applied to the calculations as much as possible. Accordingly, the final unit position determination module 243 of the present invention is closer to the unit position where the error between the first unit position and the second unit position is smaller, that is, the area connecting the plurality of unit positions is smaller. location can be determined.

At this time, since the ratio of the area of the area of the first unit location P _1n and the second unit location P _2n is proportional to the square of the distance between each unit location, the square root of the area of the area formed by each unit location It can be weighted and calculated in inverse proportion to the ratio of Therefore, as shown in the equation below, the final unit position (P _3n ) may be determined as a position dividing the first unit position (P _1n ) and the second unit position (P _2n ) at a predetermined ratio according to the area formed by each unit position. there is.

P _1n : first unit position of receiver (Bn) P _2n : second unit position of receiver (Bn)

A ₁ : Area of the area formed by the first unit positions

A ₂ : area of the area formed by the second unit locations

In another embodiment of the present invention, the final unit position may be calculated based on the second unit position of the strongest receiver. Depending on the application or system, measuring the positioning of the transmitter may require minimum calculation or a fast time. In this case, the distance and azimuth from the strongest receiver are estimated as the most accurate second unit position (P ₂₁ ), and the first By calculating the unit position and deriving the final unit position, the speed of calculation can be reduced and the positioning of the transmitter can be measured more quickly.

The final position determination unit 25 determines the final position of the transmitter using the plurality of final unit positions. As shown in FIG. 13, the final position P _f exists within a space enclosed when the final unit positions P ₃₁ , P ₃₂ , P ₃₃ , and P ₃₄ are connected with a straight line. For example, the average value of these four coordinates Through this, the final position is calculated. Since the final position is calculated through this process, the position of the emitter can be captured similarly to the actual one. The final location revealed through this process can be displayed on a map to express the current location, or it is possible to provide various location information-based services such as identifying information on the location of children or logistics.

Hereinafter, a positioning method according to an embodiment of the present invention will be described. The positioning method synthesizes the final unit position calculated through a plurality of first unit positions derived based on the signal strength between the transmitter and the receiver, and the second unit position derived based on the distance and azimuth between the transmitter and the receiver. By selecting the final location of the transmitter, the reliability of position measurement can be increased. By using the distance and azimuth of the transmitter coming through the AoA receiver, the distance and azimuth of the transmitter are added to the position measurement process using the existing wireless signal strength. You can increase the accuracy by doing this. The positioning method includes a radio signal normalization method (S3) and a position measurement method (S5).

The applicant looks at the radio signal normalization method (S3) with reference to FIGS. 6 to 8 below. According to another embodiment of the present invention, the radio signal normalization method of the present invention includes a radio signal receiving step of receiving radio signals from a plurality of receivers (S30), a maximum fluctuation range setting step (S31), a signal strength determining step (S34), It includes list management step (S35), signal strength averaging step (S37), distance averaging step (S38), and azimuth averaging step (S39).

The radio signal receiving step (S30) is a step in which the receiving unit 11 receives the radio signal transmitted by each receiver and transmits it to the signal strength determining unit 12.

The maximum fluctuation width setting step (S31) refers to the maximum physically possible value as the difference between the current signal strength and the previous signal strength of the transmitter that can be physically measured when the transmitter moves, and these maximum fluctuation widths C are set. .

The signal strength determination step (S34) is a step of detecting the movement of the transmitter and determining the signal strength by interlocking the maximum variation C and the signal strength of the wireless signal of the receiver received from the receiver, the signal strength determination step (S341), It includes a signal strength increasing step (S343) and a signal strength decreasing step (S345).

The signal strength determination step (S341) determines whether the difference between the current signal strength and the previous signal strength of the wireless signal received by the receiver is greater than or less than the maximum fluctuation range C.

The maximum fluctuation range C means the maximum physically possible value as the difference between the previous signal strength and the next signal strength of the transmitter when the transmitter moves. For example, when the transmitter approaches from receiver B1 to B4, the radio signal strength of receiver B1 receiving the transmitter's radio signal decreases and the radio signal strength of receiver B4 receives the transmitter's radio preference increases. There is a physically possible range of fluctuations in signal strength that can occur due to the movement of (1). Fluctuations in signal strength, which means fluctuations in distances that transmitters cannot move in a short time, cause instability of wireless signals.

In the signal strength determination step (S341), when the difference value E between the previous signal strength and the current signal strength of the same receiver is smaller than the maximum fluctuation range C, the current signal strength is used as the input signal without change. This means that if the difference value E is smaller than the maximum fluctuation range C, it means that the transmitter moved within the physically possible movement range, so the current signal strength is used as it is. However, when the difference value E of the signal strength is greater than the maximum fluctuation range C, the following signal strength increasing step and signal strength decreasing step are performed.

The signal strength increasing step (S343) is a step of replacing the current signal strength by adding the maximum variation width C to the previous signal strength when the current signal strength of the same receiver is greater than the previous signal strength, and the signal strength decreasing step (S345) is the same If the current signal strength of the receiver is smaller than the previous signal strength, it is a step of subtracting the maximum fluctuation range C from the previous signal strength and replacing it with the current signal strength.

The signal strength derivation step (S347) is a step of determining the final signal strength through the above signal strength determination step (S341), signal strength increasing step (S343) and signal strength decreasing step (S345).

The list management step (S35) is a step of inputting a predetermined number of signal strengths output from the signal strength determining step for each receiver into a queue and deleting the oldest signal strength. The radio signals determined by the signal strength determination unit are input to the queues (Q1, Q2, Q3, Q4) as shown in FIG. 4, and the oldest signal strength is deleted when the number of input signal strengths exceeds the predetermined number. do. Referring to FIG. 4, the signal strength of the five radio signals transmitted from the receiver B1 is the signal strength of the five radio signals determined by the signal strength determination unit as seen above input to the cue Q1, and all of the cues Q2, Q3, and Q4 Through the same process, the radio signal strengths of the receivers B2, B3, and B4 are input.

The signal strength average step (S37) is a step of defining the average value of the signal strength input to the queue through the list management step as the signal strength of the corresponding receiver. When the queue is filled with a predetermined number, the average of the signal strengths filled is defined as the signal strength of the corresponding receiver. In FIG. 4, reference numeral A is the average value and the radio signal strength, and this value is used for positioning. Therefore, the signal strength, which has changed over 5 times in each receiver, is stabilized by the average value. For example, receiver B1 shows signal strengths of -54, -59, -55, -62, -60, but the average value is -58, receiver B2 averages -64.8, receiver B3 -72.4, and receiver B4 becomes -82.

The distance averaging step (S38) is a step of defining the average value of the distance input to the queue through the list management step as the distance between the transmitter and the receiver. When the queue is filled with a predetermined number, the filled distance is averaged and defined as the distance between the transmitter and the receiver. An average value indicated by reference numeral A in FIG. 4 may be defined as the distance, and an average value of Q5 to Q8 defined as the distance is used for positioning. Therefore, it is stabilized by the average value of the distances changed over 5 times in each receiver. For example, receiver B1 shows distances of 2, 2.1, 1.9, 2, 2.2, but the average is 2.04, receiver B2 is 1.92, receiver B3 is 1.88, and receiver B4 is 2.08.

The azimuth averaging step (S39) is a step of defining the average value of the azimuth input to the queue through the list management step as the azimuth of the transmitter. When the number set in the queue is all filled, the filled azimuths are averaged and defined as the azimuth of the transmitter. As can be seen in FIG. 4, the average value of reference numeral A is defined as an azimuth, and the average value of Q9 to Q12 is used for positioning as an azimuth. Therefore, it is stabilized by the average value of the azimuth that has changed over five times in each receiver. For example, receiver B1 shows azimuths of 260, 255, 257, 264, and 262, but the average value is 259.6, receiver B2 averages 259.4, receiver B3 has 260.2, and receiver B4 has 260.6.

The applicant looks at the transmitter location measurement method with reference to FIGS. 6 and 9 to 12 below.

Referring to FIG. 9, the position measurement method measures the position of the transmitter 1 based on the normalized radio signal or non-normalized signal strength seen above, and the receiver list determination step (S51) and the neighbor determination step (S53). ), a unit position calculation step (S55), a final unit position calculation step (S56), and a final position determination step (S57).

The receiver list determination step (S51) includes a receiver number setting step (S511) for defining the number of receivers to participate in positioning and a receiver sorting step for arranging the receiver list in the order of receivers showing strong signal strength within a predetermined number range ( S513). Referring to FIG. 1, when four receivers are used to determine the location of an emitter, these receiver lists include information sorted in the order of B1, B2, B3, and B4. The number of these receivers can be changed as needed. As the number increases, the accuracy of position measurement increases, but there is a problem that the time for position measurement increases due to the increase in the amount of data, so it is necessary to select them appropriately.

The receiver list determination step (S51) calculates the distance between the previous position of the transmitter and the receiver that currently transmits the radio signal, and if it is greater than the distance threshold value F, the receiver is excluded from the receiver list to reduce the error of position measurement. An exclusion step (S515) is further included. If the distance from the previous position of the transmitter among the receivers in the receiver list is greater than the distance between the previous positions of other receivers and transmitters, the wireless signal transmitted from the corresponding receiver is regarded as unstable and excluded. In order to reduce errors in positioning, A distance threshold F is defined, and if the distance exceeds the distance threshold F, the corresponding receiver is deleted from the list.

The adjacency determination step (S53) determines the case where the transmitter 1 is located adjacent to a predetermined receiver in a space where a plurality of receivers are installed. If the signal strength difference value R between the strongest receiver and the chagang receiver is greater than or equal to a predetermined signal strength threshold, it is determined that the transmitter is adjacent to the strongest receiver, and the coordinates of the strongest receiver are determined as the position of the transmitter. For example, if the receiver is installed on the ceiling or in a high place, if the emitter is not brought very close to the receiver, the strength of the wireless signal cannot be shown as much as when it is adjacent. If you do, it is determined that the transmitter is located at a predetermined point between the strongest receiver and the car receiver, but as above, if the difference value R is greater than the signal strength threshold G according to the adjacency determination step, the position of the receiver is determined as the position of the strongest receiver This increases the accuracy of positioning. In this case, the operation by the unit position calculation step below is not performed.

The unit position calculation step (S55) calculates the first unit position of the transmitter between the strongest receiver and the receiver in the receiver list determined by the receiver list determining step. As seen above, within the receiver list, the chagang receiver refers to all receivers other than the strongest receiver, and the first unit position is the position of the terminal on a straight line connecting the strongest receiver and the remaining chagang receivers. As shown in FIG. 11, the coordinates of receiver B1 are P ₁ , the coordinates of receiver B2 are P ₂ , the coordinates of receiver B3 are P ₃ , the coordinates of receiver B4 are P ₄ , and the first unit position is the strongest receiver B1. Coordinates of _P1 , coordinates of transmitter _P12 on a straight line between the strongest receiver B1 and receiver B2, and coordinates of transmitter _P13 on a straight line between the strongest receiver B1 and receiver B3, and on a straight line between the strongest receiver B1 and receiver B4 It becomes the coordinates P ₁₄ of the transmitter. The first unit position may be calculated by various formulas. For example, the unit position P _1n is determined by the above-mentioned formula.

It is preferable to include the coordinates of the strongest receiver in the first unit position because it can increase the accuracy of position measurement. And, whether or not to include the coordinates of the strongest receiver used for position measurement in the unit position may be dependently changed according to a formula.

The final unit position calculation step (S56) is a step of determining the final unit position by additionally calculating the distance and azimuth angle of the emitter and the receiver with respect to the first unit position. It is possible to increase the accuracy of position measurement by determining the final unit position by calculating the second unit position of the transmitter determined by the first unit position and the distance and azimuth of the transmitter and receiver. As described above, the first unit location is a point located on the straight lines connecting the strongest receiver and the car receiver, but in fact, the transmitter 1 is located at any one point in the area between the plurality of receivers, Even if the coordinates of one unit position are averaged, a certain degree of error may occur with the actual position of the emitter. In order to minimize the resulting error, the final unit position calculation unit 24 calculates a second unit position that may have coordinates that deviate from the straight lines connecting the strongest receiver and the car receivers through data of a different nature from the signal strength. It is possible to further reduce the error between the measured position and the position of the emitter by determining and calculating the final unit position through the second unit position and the previously derived first unit position. The final unit position calculation step (S56) includes a second unit position determining step (S561) and a final unit position determining step (S563).

In the second unit position determining step (S561), the second unit position of the transmitter is determined based on the distance and azimuth between the transmitter and the receiver measured by the receiver. Preferably, the distance and azimuth angle used to determine the second unit position are the normalized distance and azimuth angle described above. As shown in FIG. 11, the distance between the receiver B2 and the position Pf of the emitter is D2, the azimuth is Z2, and the second unit position P ₂₂ can be calculated using the distance and the azimuth. The second unit position P _2n is calculated in the same way for other receivers.

In the final unit position determining step (S563), the second unit position (P _2n ) is calculated with the first unit position (P _1n ) determined by the unit position calculating unit to determine the final unit position (P _3n ). In one embodiment of the present invention, the first unit position (P _1n ) and the second unit position (P _2n ) may be averaged to determine the final unit position. In a preferred embodiment of the present invention, when determining the final unit position, the final unit position ₍ P 3n ) can be derived by averaging the first unit position (P _1n ) and the second unit position (P _2n ) for each receiver. there is.

In another embodiment of the present invention, the final unit position may be calculated at a different ratio according to the area area between the first unit location P _1n and the area area between the second unit location P ₂₂ of each receiver. Referring to FIG. 12, the first unit position (P _1n ) and the second unit position (P ₂₂ ) may be calculated differently from a plurality of receivers according to the type of receiver, and the first unit position (P _1n ) between The area between the area and the second unit location P ₂₂ may also be calculated differently. When the area between the second unit locations P _2n is smaller than the area between the first unit locations P _1n , the second unit location P _2n can be estimated as a relatively accurate unit location. there is. In this case, the final unit position is not derived by averaging the first unit position (P _1n ) and the second unit position (P _2n ), but the final unit position (P _3n ) is derived close to the second unit position (P _2n ). Weights can be applied to the calculations as much as possible. Accordingly, in the final unit position determining step (S563) of the present invention, the error between the first unit position and the second unit position is smaller, that is, the area connecting the plurality of unit positions is closer to the unit position with the smaller area. location can be determined. As described above, in one embodiment of the present invention, each unit location may be weighted and calculated in inverse proportion to the ratio of the square root of the area of the area formed.

In another embodiment of the present invention, the final unit position may be calculated based on the second unit position of the strongest receiver. Depending on the application or system, measuring the positioning of the transmitter may require minimum calculation or a fast time. In this case, the distance and azimuth from the strongest receiver are estimated as the most accurate second unit position (P ₂₁ ), and the first By calculating the unit position and deriving the final unit position, the speed of calculation can be reduced and the positioning of the transmitter can be measured more quickly.

The final positioning step (S57) determines the final position of the transmitter using the plurality of final unit positions. As shown in FIGS. 11 and 12, the final position P _f exists in a space enclosed when unit positions P _31, P ₃₂ , P ₃₃ , and P ₃₄ are connected with a straight line, and for example, the average value of these four coordinates. The final position is calculated through . Since the final position is calculated through this process, the position of the terminal can be captured similarly to the actual one. The final location revealed through this process can be displayed on a map to express the current location, or it is possible to provide location information-based services such as identifying information on the location of children or logistics.

Although the applicant has looked at the embodiments implementing the technical details of the present invention above, the scope of the present invention should be construed as including various changes and modifications without being limited only to the above embodiments.

b1, b2,,,,bn: Receiver 1: Transmitter 3: Server
10: radio signal normalization unit 11: receiver 12: signal strength determination unit
15: list management unit 16: normal signal strength calculation unit 17: regular distance calculation unit
18: normal azimuth calculation unit
20: Position measurement unit 21: Receiver list determination unit 22: Adjacent determination unit
23: unit position calculation unit 24: final unit position determination unit
241: second unit position determination module 243: final unit position determination module
25: final position determining unit
S3: Radio signal normalization method
S30: wireless signal receiving step S31: maximum variation width setting step S34: signal strength determining step
S35: list management step S37: signal strength average step S38: distance average step
S39: azimuth averaging step
S5: Location measurement method
S51: receiver list determination step S53: neighbor determination step
S55: unit position calculation step S56: final unit position calculation step
S57: final positioning step

Claims (17)

It includes a plurality of receivers for receiving radio signals transmitted from the transmitter, and a server for receiving radio signal information from the plurality of receivers,
The server includes a receiver list determination unit that defines the number of receivers to participate in position determination, a unit position calculation unit that calculates the first unit position of the transmitter according to the radio signal of each receiver on the receiver list determined by the receiver list determination unit, and the transmitter A position measurement unit having a final unit position calculation unit for deriving the second unit position of and calculating the final unit position of the transmitter together with the first unit position and a final position determining unit for determining the position of the transmitter based on the final unit position positioning system. The positioning according to claim 1, wherein the first unit position is determined according to the signal strength of the transmitter and the receiver, and the second unit position is determined based on at least one of a distance and an azimuth angle between the transmitter and the receiver. system. The method of claim 2, wherein the receiver list determination unit arranges the receiver list in the order of receivers showing strong signal strength within a predetermined number of ranges, and the unit position operation unit determines the strongest receiver and the strongest receiver based on the signal strength of the strongest receiver and the weakest receiver. Calculate the first unit position of the emitter between at least one or more chagang receivers,
Wherein the first unit position is defined on a straight line between the strongest receiver and the car receiver. The unit position calculation unit according to claim 3, wherein the final unit position calculation unit determines the second unit position of the transmitter based on the distance and azimuth angle between the transmitter and the receiver measured by the receiver, and the second unit position is determined by the unit position calculator And a final unit position determination module for determining the final unit position by calculating the first unit position determined in
The positioning system, characterized in that the final position determination unit determines the final position of the transmitter by calculating a plurality of final unit positions. The positioning system according to claim 4, wherein the final unit position determination module determines the final unit position by averaging the first unit position and the second unit position measured for each receiver. The method of claim 4, wherein the final unit position determining module determines a final unit position closer to a unit position having a smaller width of an area connecting each unit position among the first unit position and the second unit position measured for each receiver, , The final unit position is weighted and calculated in inverse proportion to a ratio of a square root of an area formed by a plurality of first unit positions and second unit positions. The positioning system according to claim 4, wherein the final unit position determination module calculates the final unit position of each receiver by calculating the second unit position of the strongest receiver with the first unit positions of the strongest receiver and the car receivers. According to any one of claims 1 to 7,
The receiver list determination unit arranges the receiver list in the order of receivers showing strong signal strength within a predetermined number of ranges,
The location measurement unit further comprises a neighbor determination unit for determining that the transmitter is adjacent to the strongest receiver when the difference in signal strength between the strongest receiver and the strongest receiver in the receiver list is equal to or greater than a predetermined signal strength threshold. system. The method of any one of claims 1 to 7, wherein the receiver list determination unit calculates the distance between the receiver currently transmitting the radio signal and the previous position of the transmitter, and if it is greater than the distance threshold, the receiver is selected from the receiver list. Positioning system characterized in that to reduce the error of position measurement by excluding.
A receiver list determination step in which wireless signal information is transmitted to a server from a plurality of receivers that have received radio signals transmitted from transmitters and the number of receivers to participate in position determination is defined, and each receiver on the receiver list determined by the receiver list determination step The unit position calculation step of calculating the first unit position of the transmitter according to the radio signal of the transmitter, the final unit position calculation step of deriving the second unit position of the transmitter and calculating the final unit position of the transmitter together with the first unit position, and the above A positioning method comprising a final position determination step of determining the position of the transmitter based on the final unit position. 11. The method of claim 10, wherein the first unit position is determined according to the signal strength of the transmitter and the receiver, and the second unit position is determined based on at least one of a distance and an azimuth angle between the transmitter and the receiver. method. The method of claim 11, wherein the receiver list determining step sorts the receiver list in the order of receivers showing strong signal strength within a predetermined number of ranges, and the unit position calculation step is based on the signal strength of the strongest receiver and the strongest receiver. Calculate the first unit position of the emitter between the receiver and at least one chagang receiver,
Wherein the first unit position is defined on a straight line between the strongest receiver and the car receiver. The method of claim 12, wherein the final unit position calculation step is a second unit position determining step of determining the second unit position of the transmitter based on the distance and azimuth angle between the transmitter and the receiver measured by the receiver, and the second unit position as the unit position And a final unit position determination step of determining a final unit position by calculating the first unit position determined by the operation unit,
The positioning method, characterized in that the final position determination step determines the final position of the transmitter by calculating a plurality of final unit positions. 14. The method of claim 13, wherein the step of determining the final unit position determines a final unit position closer to a unit position having a smaller width of an area connecting each unit position among the first unit position and the second unit position measured for each receiver; ,
The final unit position is weighted and calculated in inverse proportion to a ratio of a square root of an area formed by a plurality of first unit positions and second unit positions. The positioning method according to claim 13, wherein the final unit position determination step determines the final unit position by averaging the first unit position and the second unit position measured for each receiver. According to any one of claims 10 to 15,
In the receiver list determining step, the receiver list is arranged in the order of receivers showing strong signal strength within a predetermined number of ranges, and the positioning method determines that the difference between the signal strength of the strongest receiver and the strongest receiver in the receiver list is a predetermined signal strength threshold. The positioning method further comprises a neighbor determination step of determining that the transmitter is adjacent to the strongest receiver if the value is greater than or equal to the value. The method of any one of claims 10 to 15, wherein the receiver list determining step calculates a distance between a receiver currently transmitting a radio signal and a previous position of the transmitter, and if the distance is greater than a threshold value, the corresponding receiver is selected from the receiver list. Positioning method characterized in that to reduce the error of position measurement by excluding from.

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