KR20180090646A - Method and apparatus for location estimating using gis information - Google Patents

Abstract

According to an aspect of the present invention, a position estimation apparatus using GIS information comprises: a GPS signal receiving part for receiving a GPS signal from a satellite; a position calculating part for estimating the initial position of the position estimation apparatus using the received GPS signal; a communication part for receiving GIS information around the initial position from a GIS server; and a position correcting part for correcting the estimated initial position with the received GIS information and determine the final position of the position estimation apparatus. It is possible to increase the accuracy of position estimation.

Description

Field of the Invention [0001] The present invention relates to a method and apparatus for estimating a position using GIS information,

More particularly, the present invention relates to a method of compensating an error occurring in the position estimation by using GIS (Geographic Information System) information due to the occurrence of multipath in the process of receiving a signal from a satellite, ≪ / RTI >

The conventional position measurement method estimates a position using a triangulation method using signal information received from a Global Navigation Satellite System (GNSS) satellite.

However, when a multipath occurs in a signal path between a satellite and a position measuring device such as a car navigation device due to a surrounding environment such as a building in a city environment, an error of several meters may occur at a few meters.

1 shows the difference in visibility of the satellite according to the position of the vehicle.

The solid line represents the LOS (Line Of Sight) signal, and the dotted line represents the NLOS (Non-Line of Sight) signal.

When the vehicle is in the position A, the SV2 satellite and the SV3 satellite can receive the LOS signal while the visibility is secured, but the SV1 satellite can not receive the LOS signal because the visibility is not secured.

Likewise, when the vehicle is in the position of B, the LOS signal can not be received from the SV3 satellite.

In this case, because the building is located at the location of A or B, if the satellite is blocked and the NLOS signal is received, there will be an error in the estimation of the position.

Various hardware and software methods have been studied to compensate for this, but there is a fundamental limitation because it depends on the multipath signal.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a position estimating apparatus and a method therefor which can improve the accuracy of position estimation by supplementing satellite signals using GIS information.

The objects of the present invention are not limited to the above-mentioned objects, and other objects not mentioned can be clearly understood by those skilled in the art from the following description.

According to an aspect of the present invention, there is provided a position estimation apparatus using GIS information, comprising: a GPS signal receiver for receiving GPS signals from satellites; A position calculator for estimating an initial position of the position estimating apparatus using the received GPS signal; A communication unit for receiving GIS information around the initial location from the GIS server; And a position correcting unit for correcting the estimated initial position with the received GIS information to determine a final position of the position estimating apparatus.

According to another aspect of the present invention, there is provided a method of estimating a position using GIS information, comprising: receiving a GPS signal from a satellite; Estimating an initial position of the position estimating apparatus using the received GPS signal; Receiving GIS information around the initial location from a GIS server; And determining the final position of the position estimating apparatus by correcting the estimated initial position with the received GIS information.

According to the present invention, it is possible to estimate the position more accurately even in a place where a satellite signal is disturbed due to multiple paths such as reflection, diffraction, and scattering due to a surrounding environment such as a building.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a view showing a reception state of a satellite signal according to a vehicle position; FIG.
2 is a diagram showing a signal intensity of an LOS signal;
3 is a diagram showing signal intensity of an NLOS signal;
4 is a structural view of an entire system including a position estimating apparatus according to an embodiment of the present invention;
FIG. 5 illustrates a 3D map of a building formed according to an embodiment of the present invention. FIG.
6 is a structural diagram of a position estimation apparatus according to an embodiment of the present invention;
7 is a graph showing a probability density function of an LOS signal and an NLOS signal;
8 is a flowchart of a method of estimating a position according to an embodiment of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS The advantages and features of the present invention, and the manner of achieving them, will be apparent from and elucidated with reference to the embodiments described hereinafter in conjunction with the accompanying drawings. The present invention may, however, be embodied in many different forms and should not be construed as being limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. Is provided to fully convey the scope of the invention to those skilled in the art, and the invention is only defined by the scope of the claims. It is to be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. In the present specification, the singular form includes plural forms unless otherwise specified in the specification. As used herein, the terms " comprises, " and / or "comprising" refer to the presence or absence of one or more other components, steps, operations, and / Or additions.

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

As shown in FIG. 1, when the NLOS signal is received, the signal of the satellite SV1 can not be properly received because it is hidden in the building at the position A. Therefore, the SV1 satellite signal (GPS signal) is multipath generated, and an error occurs in the position estimation.

In order to solve such a problem, the present invention aims to estimate a more accurate position by correcting the position of a satellite using GIS information.

GIS is an abbreviation of Geographic Information System (Geographical Information System), which digitally maps geographical information from all over the country and creates it as a digital map. Through various information and communication technologies, GIS is used for disaster, environment, facilities, Is an advanced information system that we want to utilize.

The GIS information includes terrain information and building information. Using the location information, the shape, the width, the length and the height information of the building information, it is possible to determine whether the building exists as an obstacle between the specific location and the satellite have. When the building exists as an obstacle between the specific location and the satellite from the GIS information and the GPS information, the received satellite signal (GPS signal) is determined as a Non-Line Of Sight (NLOS) signal. If there is no building as an obstacle, the received satellite signal is determined as a LOS (Line Of Sight) signal. In the case of the NLOS signal, the satellite signal is estimated to be transmitted along the multipath, and in the case of the LOS signal, the satellite signal may be estimated to be transmitted through the linear path.

First, using the GIS information in the situations shown in FIGS. 1 to 3, the received satellite signal can be classified into the LOS signal or the NLOS signal. The received satellite signal may be either an LOS signal or an NLOS signal, and a probabilistic distribution of the satellite signal may be estimated using a radio channel propagation model according to each signal. At this time, the probability distribution of the satellite signal is precisely estimated using the intensity of the satellite signal, the transmission time, and the SNR (Signal-to-Noise Ratio).

The wireless channel propagation model is a model of electromagnetic wave propagation characteristics by reflecting empirical results in the theoretical equation to reflect the signal characteristics of a wireless mobile communication environment.

In the present invention, a radio channel propagation model is used to analyze fading due to multipath such as reflection, diffraction, scattering of a GNSS signal. Typically, a Rician Distribution Model and a Rayleigh Distribution Model Model) are used, which are classified according to the probability distribution characteristic of the power spectrum (PSD).

As shown in FIG. 2, the Rician distribution model models a case where the intensity of the LOS signal S1 arriving without disturbance of the obstacle is greater than the intensity of the NLOS signals S2 and S3 where the fading phenomenon occurs. Normally, the LOS signal is a signal that arrives in a straight path without reflection, diffraction, scattering, etc., so that the intensity of the signal is larger than that of the NLOS signal and the propagation time is also short. For example, in the case of FIG. 2, the NLOS signals S2 and S3 are reflected, diffracted, and scattered on a building to weaken the intensity of the signal, and the propagation time becomes longer due to the longer optical path. A Rician distribution model can be applied to the LOS signal S1 for a hypotenuse signal in which such a characteristic is clearly displayed. However, the occurrence of multipaths showing the characteristics of reflection, diffraction, and scattering can occur in various situations, and thus there is a problem in that there is a large error in determining only by the characteristics of the satellite signals. In the GIS information, the position, shape, When information is further utilized, it is possible to precisely determine whether the satellite signal is the LOS signal or the NLOS signal.

The Probability Density Function (PDF) used in the Rician distribution model is shown in Equation 1 below.

r is the signal intensity, I is the Bessel function, and σ and μ are the mean and variance of the probability density function, respectively.

On the other hand, the Rayleigh distribution model models the probabilistic distribution of the signal when only the NLOS signals (S2, S3) receiving the fading due to the obstacle are received as shown in FIG. As shown in Fig. 3, the LOS signal S1 is blocked by the obstacle, and only the NLOS signal is received. As compared with FIG. 2, since there is no reference LOS signal, it can be determined that the NLOS signal is based on the signal strength and the transmission time.

However, it is difficult to clearly distinguish between the size of the first reflected NLOS signal and the size of the second reflected NLOS signal, and therefore, the size and transmission of the NLOS signal There is a problem that it is difficult to grasp the optical path with time only, and there is a problem that a large error (up to several hundreds of meters) occurs in predicting the vehicle position by triangulation using GPS satellite signals.

In the present invention, since only the NLOS signal is determined by using the signal size and the transmission time, it is possible to clearly distinguish the LOS signal and the NLOS signal. However, since it is simultaneously determined whether the satellite signal is the LOS signal or the NLOS signal, the GIS information is used together with the intensity of the satellite signal, the transmission time, and the SNR information, (LOS signal or NLOS signal) can be accurately judged.

The probability density function of the Rayleigh distribution model is shown in Equation 2 below.

FIG. 4 illustrates a structure of an overall system in which a position estimation method according to an embodiment of the present invention is performed.

The position estimating apparatus 400 receives a signal for position estimation from the satellite 100 and receives information from the A-GPS server 200 for using the existing GNSS and the GIS server 300 for transmitting the GIS information .

A-GPS (Assisted GPD) means a satellite-based position acquisition system that improves the GPS start-up speed under certain conditions and reduces the time it takes until the first satellite and data link are fixed, Or used primarily in smartphones. While Stand-alone GPS (S-GPS) works independently by using GPS satellite radio signal, A-GPS uses satellite signal more quickly by utilizing wireless network resources to obtain position, Multipath propagation phenomenon, and propagation attenuation phenomenon. The A-GPS can provide the orbit information and the ephemeris data of the GPS satellite to the communication unit 420 and the snapshot of the GPS signal for the position information processing can be stored in the server so that weak signals can be compared and analyzed, Position calculation is enabled. However, even if A-GPS is used, the time required to fix the required satellite and data link (TTFF, Time to First Fix) becomes too long in a densely populated area in the city where almost no LOS signal can be received In the present invention, the A-GPS server and the GIS server can be used together to accurately estimate the position.

The location estimation apparatus 400 receives the terrain information and building information from the GIS server 300, which is called GIS information. The GIS information includes the location, shape, width, length and height information of the building. In addition, a 3D map can be formed using the received GIS information.

Using the satellite signal received from the satellite 100, the information received from the A-GPS server, and the GIS information received from the GIS server 300, the received satellite signal is an NLOS signal, a line of sight signal. The probability of the vehicle position is calculated using the Rayleigh distribution in the case of the NLOS signal and the Rician distribution in the case of the LOS signal. The accuracy of the vehicle position can be improved based on the calculated probability.

5 shows an example in which information is received from the GIS server 300 to form a 3D map.

When the information on the road building like FIG. 5A is received from the GIS server 300, the position estimating apparatus 400 can be formed in a 3D map form as shown in FIG. 5B.

6 is a structural diagram of a position estimation apparatus 400 according to an embodiment of the present invention.

The position estimating apparatus 400 includes a GPS signal receiving unit 410, a communication unit 420, a position calculating unit 430, and a position correcting unit 440.

The GPS signal receiving unit 410 receives the satellite signal and outputs the result of the estimation through its own algorithm (WLS, LSQ, NLSQ, KF, etc.) in the form of NMEA (National Marine Electronics Association) standard. The NMEA standard is a standard for transmitting information such as time, position, and bearing.

The GPS signal receiving unit 410 may receive the satellite signal and output the NMEA standard type data to the location information of the vehicle. In addition, the GPS signal receiving unit 410 may receive NMEA standard data from an external GPS receiver.

The communication unit 420 requests and receives information from the A-GPS server 200 or the GIS server 300. As described above, the A-GPS server 200 obtains the position of the satellite from the satellite signal more quickly and performs a part of the operation to be performed by the GPS signal receiving unit 410 in the A-GPS server 200, The calculation burden of the GPS receiver 410 is reduced and the information that is not held by the GPS signal receiver 410 and information affecting the GPS signal can be easily obtained using the information of the base station. The GIS server 300 receives the GIS information including the terrain information and the building information around the vehicle.

The position calculation unit 430 can obtain a pseudorange (distance information) for GPS positioning by using the information received from the GPS signal receiving unit 410 and the information received from the A-GPS server through the communication unit 420 have. The pseudo range means the approximate distance between the satellite and the GPS signal receiving unit 410. Transmission time, Transition time and pseudo distance can be obtained by using NMEA standard type data.

The position correcting unit 440 corrects the pseudo distance of the satellite calculated by the position calculating unit 430 by using GIS information, ionospheric delay, and delayer delay.

The position calculator 430 can estimate the current position according to the triangulation method using the pseudo distance obtained from a plurality of satellites and the position of each satellite. The estimated current position is referred to as a first position.

The position correcting unit 440 corrects the first position using the GIS information. The corrected position is referred to as a second position. In order to calculate the second position using the first position and the GIS information estimated by the position calculation unit 430, a region within a predetermined constant radius around the first position is divided into a plurality of candidate positions.

It is determined whether an obstacle such as a building exists between one satellite position and one candidate position. When there is a building as an obstacle between the satellite positions with respect to the candidate position that is the current determination target by using the GIS information, the signal of the satellite is determined as the NLOS signal. If there is no obstacle building, Is determined as the LOS signal.

(LOS signal or NLOS signal) with respect to all the satellites with respect to one candidate position, and grasps the characteristics of the satellite signals with respect to all the satellites with respect to the remaining candidate positions in the same manner.

For example, it has been experimentally known that, when GPS signals and an A-GPS server are used, errors due to multipaths are at a level of up to 200 meters. When the first position is determined using the GPS signal and the A-GPS server, the maximum error level can be divided into N candidate positions within a radius of 200m or less centered on the first position. Also, N candidate positions may be selected for fast calculation.

A uniformly distributed random generator may be used to select N candidate locations, but a random generator with a probability density function of the position predicted using the GPS signal and the A-GPS server may be used, A two-dimensional normal distribution curve can be used, but a random generator using a two-dimensional normal distribution function adjusted by taking into account the error of the current system only the standard deviation can be used.

In case of using a probability density function of a normal distribution form, it is more advantageous to an actual distribution, and there is an advantage that a second position can be determined more precisely in the vicinity of the first position, and when a uniform probability density function is used, There is a high reliability advantage of the result of the estimated second position when it is present at a position that is considerably distant from the first position (e.g., 150 m from the first position).

That is, the normal distribution function is advantageous when the first position reflects the current position well (when the error is small), and when the first position does not reflect the current position (when the error is large) It is advantageous. The present invention can correct the current position appropriately when the error is large even when using the A-GPS server, and can accurately correct the current position even when the error is small. Can be said to be in a reward relationship.

The operation according to the present invention can be performed quickly even if it is equipped with a computing power of a cellular phone level. However, in order to more precisely select a candidate position and to accurately estimate the second position, information necessary for calculation is transmitted to an external server , And the second position calculated and calculated by the external server can be received again. The function of the external server may be implemented in an A-GPS server or a GIS server, and may be constructed as a separate server.

Considering the computation time, the candidate position selection method can be divided into two or more stages.

For example, in the first step, the candidate position is selected based on the first position (for example, 50 m) by widening the interval to determine a candidate position having a high probability.

In the second step, the candidate position is selected again at a narrower interval (for example, 2 m) based on the determined candidate position, and the candidate position with high probability is determined again.

This step can be divided into three or more steps in consideration of the operation speed.

For example, assuming that the minimum error is 2 m in consideration of the length of the ordinary vehicle, and considering the square shape of the candidate position selection target area as the first position as 400 m x 400 m, 200 (400 m / 2 m) Candidate positions can be selected. At this time, if the number of dividing one side is m (m = 200 in the above example), the calculation time is in the form of O (m ² ). In the method of estimating the second position by dividing the above steps, the calculation time is O (m * log (m)) based on the accuracy of the same level, so that the gain of the calculation time can be obtained.

In the case of the first step, m = 8 (400 m / 50 m), and a total of 64 operations are performed. In the case of the above two steps, m = 25 (= 50 m / 2 m). If the steps are not divided, 40,000 calculations can be performed. If the two steps are divided into 689 calculations, a similar level of accuracy can be obtained. Theoretically, it is possible to compute approximately 150 (= 40 * ln (40)) times by adjusting the number of steps and the interval to be divided and calculate the same level of precision.

In the case of estimating the second position by dividing the steps, the distribution of the actual satellite signals between the respective candidate positions should be continuous or dense at a certain level or more. However, since the statistical distribution of the satellite signals is discontinuous depending on the location, shape, and height of the building, there is a risk that the method of dividing the steps may cause a large error in some cases.

The present invention is a method of distinguishing whether each satellite signal is an LOS signal or an NLOS signal and calculating a second position probabilistically from a first position calculated by the GPS system to correct multipath caused by the building.

However, the signal intensity and the transmission time can be different depending on the location, shape, width, height, and the like of the building at the position of the used satellite. Therefore, the SNR of the satellite signal Ratio, Signal to Noise Ratio) to estimate the probability of each candidate location from the probability density function. The signal strength and propagation time can be different depending on the propagation path, but the SNR of the satellite signal is relatively independent of the propagation path, but has a somewhat different distribution depending on whether it is the LOS signal or the NLOS signal.

SNR means the ratio between the signal of the satellite signal and the noise. If expressed in terms of the dB scale of the logarithmic scale, the SNR has a characteristic value independent of the intensity of the signal. It is well known that the SNR of a satellite signal follows the Rician distribution and the Rayleigh distribution according to the above-described radio channel propagation model, with probability distribution according to the signal-to-noise ratio. GPS signal receiver 410, because receiving the satellite signals from a plurality of satellites, define the SNR (Signal to Noise Ratio) of the satellite signal and a vector z, SNR of the i-th satellite may be denoted as z _i. That is, _{z = (z 1, z 2} , ..., z N).

It is possible to determine whether the satellite is in the LOS position or the NLOS position at a specific candidate position by using the GIS information, and the distribution of the SNR of the satellite signal according to the Rician distribution and the Rayleigh distribution, as described above, .

The SNR distribution of the LOS and the SNR distribution of the NLOS are shown in Fig. 2 (a) and (b), respectively. The Rician distribution, and the Rayleigh distribution.

To s _i is 1, then the LOS signal from the equation (3), when the NLOS signal is defined as s _i is zero.

FIG. 7 is a graph of the probability density function of Equation (3).

7 shows the probability density function of the SNR of the satellite signal. The SNR value of the satellite signal of a specific satellite can be calculated and substituted into f _LOS or f _NLOS to calculate the probability. Specifically, an accurate calculation method can be calculated using Equations (4) to (8). However, since the variables used in equations (4) to (8) are constants having a constant value, and the object of the present invention is to determine the position with the highest probability of being present in the candidate position, By using the probability values obtained from the function, the calculated positions can be compared with each other to determine the second position among the candidate positions.

After the position calculator 430 divides the candidate position about the first position, calculates the probability of determining the second position by calculating each candidate position.

Through the GIS information, the multi-path environment is analyzed to determine the range of the candidate location selection area. And a candidate position is selected at predetermined intervals in the determined candidate region. For example, the position to be predicted is within a few hundred meters in consideration of the error level. In one embodiment of the present invention, a radius of 200 m or less is set as a candidate region, and a user position candidate can be selected in units of 2m. It is to be understood that the present invention is not limited thereto.

Let K be the total number of candidate locations. Defining the index with k is k {1, 2, ....., K}.

The larger the value of K, the more accurate the result. However, the smaller the value of K, the smaller the amount of computation, but the accuracy may decrease. Since the distance between candidates becomes shorter as K becomes larger and the distance between the candidates becomes an error of the position to be predicted, when the distance between the candidates is fixed, the computation amount increases as the candidate region becomes wider. In addition to environmental analysis, it is possible to set the optimum range by repeated experiments.

When the candidate region is set, the 3D building model of the candidate region can be formed by receiving the GIS information of the candidate region from the GIS server as shown in FIG. 5 (b).

As the information of the building increases, the accuracy increases. However, since the calculation amount increases in proportion to the information, the 3D building model can be generated using the shape, width, and height information of the building.

Also, it is possible to calculate the candidate position k directly from the GIS information using the shape, width, height, position information of the building, and arrangement of the satellites.

At this time, for all candidate positions, the probability of being the current position is calculated. The candidate position having the highest probability of the calculated current position is selected as the second position.

A method for calculating a probability of a current position from a plurality of satellite signals with respect to one candidate position is as follows. It is judged that the satellite signal is the LOS signal or the NLOS signal depending on whether there is an obstacle between the candidate position and the satellite. When the satellite signal is the LOS signal, the probability is extracted by substituting the SNR value of the satellite signal into the Rician model. If the satellite signal is an NLOS signal, the probability is extracted by substituting the SNR value of the satellite signal into the Rayleigh model. The extracted probabilities for all satellites are multiplied to calculate the probability that the candidate position is the current position. The candidate position having the largest value among the calculated probability of the current position is determined as the second position.

The theory of how to calculate the probability of the current position is as follows. The probability for the candidate position k when the SNR vector z of the satellite signal received from each satellite is given according to the conditional probability calculation method is expressed by Equation (4).

When the number of satellites is N, the SNR vector z = (z ₁ , z ₂ , ..., z _N ) and z _i means the SNR value of the i th satellite.

Can be applied to each satellite using the vector z, and can be expressed by the following Equation (5).

은 수학식 7과 같이 정의할 수 있다.Let p (k) denote the probability of each candidate. Set the probability of the initial candidate group to follow the uniform distribution as shown in Equation (6) before repeatedly calculating the probability,

Can be defined as shown in Equation (7).

은 후보 위치(k)별로 차이가 없는 상수에 해당하고, 본 발명에서는 각 후보 위치 별로 계산된 현재 위치일 확률을 상대적으로 비교하면 족하므로,

의 값만 구하면 충분하다.The p (k) and the constant

In the present invention, it is sufficient to compare the probability of the current position calculated for each candidate position relatively,

It is sufficient to obtain only the value of.

Using the above equations, the probability of each satellite shown in Equation (4) can be finally obtained as shown in Equation (8).

를 구할 수 있고, 이를 수학식 5에 대입하여

를 계산할 수 있고, 이를 수학식 4에 대입하면

를 구할 수 있다. 각 위성으로부터 수신한 SNR 벡터 z와, GIS 정보를 이용하여 후보 영역 내의 후보 위치 k에 사용자가 있을 확률(현재 위치일 확률)이 계산된다.Using equation (8)

, And substituting this into Equation 5

, And substituting this into Equation 4

Can be obtained. The SNR vector z received from each satellite and the GIS information are used to calculate the probability that the user is present at the candidate position k in the candidate region (probability of the current position).

Therefore, the candidate position with the highest probability of the user can be determined as the final position (second position) of the user.

Since the user's location information obtained in this way considers both the LOS signal and the NLOS signal of the satellite using not only the GPS signal but also the GIS information, there is an effect that the positioning error due to the multipath of the GPS signal can be reduced.

8 is a flowchart of a method of estimating a position according to an embodiment of the present invention.

A GPS signal is received for initial position estimation (S810).

The initial position is estimated using the received GPS signal. If the initial position is calculated without distinguishing between the LOS signal and the NLOS signal, an error of up to 200 m may occur due to the delayed signal due to the multipath. However, since the NLOS signal is a multipath signal and the probability of existence of a predicted position increases in the vicinity of a location where the NLOS signal is generated, if the LOS signal and the NLOS signal can be distinguished from each other, There will be.

In order to correct the estimated initial position, the initial position is transmitted to the GIS server, and the building information around the initial position is received from the GIS server (S830).

When the building information is received, it is possible to model the LOS and NLOS of each satellite at the candidate position around the estimated initial position, and the signal distribution of the candidate position can be obtained by the Rician distribution or the Rayleigh distribution. The final position can be probabilistically estimated (S840).

The detailed method of the final position estimation is as described above.

Meanwhile, the position estimation method using GIS information according to the embodiment of the present invention can be implemented in a computer system or recorded on a recording medium. The computer system may include at least one or more processors, a memory, a user input device, a data communication bus, a user output device, and a storage. Each of the above-described components performs data communication via a data communication bus.

The computer system may further comprise a network interface coupled to the network. The processor may be a central processing unit (CPU), or a semiconductor device that processes instructions stored in memory and / or storage.

The memory and the storage may include various forms of volatile or non-volatile storage media. For example, the memory may include ROM and RAM.

Therefore, the position estimation method using GIS information according to the embodiment of the present invention can be implemented by a method executable by a computer. When a method of estimating a position using GIS information according to an embodiment of the present invention is performed in a computer device, computer-readable instructions can perform the recognition method according to the present invention.

Meanwhile, the position estimation method using the GIS information according to the present invention described above can be implemented as a computer-readable code on a computer-readable recording medium. The computer-readable recording medium includes all kinds of recording media storing data that can be decoded by a computer system. For example, there may be a ROM (Read Only Memory), a RAM (Random Access Memory), a magnetic tape, a magnetic disk, a flash memory, an optical data storage device and the like. The computer-readable recording medium may also be distributed and executed in a computer system connected to a computer network and stored and executed as a code that can be read in a distributed manner.

While the present invention has been described in detail with reference to the accompanying drawings, it is to be understood that the invention is not limited to the above-described embodiments. Those skilled in the art will appreciate that various modifications, Of course, this is possible. Accordingly, the scope of protection of the present invention should not be limited to the above-described embodiments, but should be determined by the description of the following claims.

100: satellite
200: A-GPS server
300: GIS server
400: position estimating device
410: GPS signal receiver
420:
430:
440:

Claims (10)

1. A position estimation apparatus comprising at least one processor,
A GPS signal receiving unit for receiving a GPS signal from a satellite;
A position calculator for estimating an initial position of the position estimating apparatus using the received GPS signal;
A communication unit for receiving GIS information around the initial location from the GIS server; And
A position correcting unit for correcting the estimated initial position with the received GIS information to determine a final position of the position estimating apparatus;
And a position estimating unit for estimating a position of the object based on the GIS information.
The communication device according to claim 1,
And receiving the type, width, and height information of a building within a predetermined radius set around the estimated initial position from the GIS server
Position estimation apparatus using GIS information.
The apparatus of claim 1, wherein the position correcting unit
The information about buildings estimated around the initial position is analyzed based on the received GIS information, and a plurality of candidate positions within a predetermined constant radius centering on the estimated initial position based on the analyzed information about the surrounding buildings (LOS) or NLOS (Non-Line of Sight) information for each satellite in the satellite, and corrects the initial position using the information
Position estimation apparatus using GIS information.
The apparatus as claimed in claim 3, wherein the position correcting unit
If the position of the satellite is the LOS position at the candidate position, calculates the probability density of the GPS signal by applying the SNR value of the specific GPS signal to the Rician Distribution Model at the candidate position, Calculating the probability density of the GPS signal by applying an SNR value of a specific GPS signal to a Rayleigh Distribution Model
Position estimation apparatus using GIS information.
5. The apparatus of claim 4, wherein the position correcting unit
Multiplying the probability density of a plurality of GPS signals corresponding to individual candidate positions to calculate a probability of being a current position and determining a candidate position having the greatest probability of the current position as a final position
Position estimation apparatus using GIS information.
A method for estimating a position performed by a position estimating apparatus including at least one processor,
Receiving a GPS signal from a satellite;
Estimating an initial position of the position estimating apparatus using the received GPS signal;
Receiving GIS information around the initial location from a GIS server; And
Determining the final position of the position estimating apparatus by correcting the estimated initial position with the received GIS information;
The method comprising the steps of:
7. The method of claim 6, wherein receiving the GIS information comprises:
And receiving the type, width, and height information of a building within a predetermined radius set around the estimated initial position from the GIS server
A method for estimating a location using GIS information.
7. The method of claim 6, wherein determining the final position comprises:
The information about buildings estimated around the initial position is analyzed based on the received GIS information, and a plurality of candidate positions within a predetermined constant radius centering on the estimated initial position based on the analyzed information about the surrounding buildings (LOS) or non-line of sight (NLOS) information for each satellite on the basis of the information about the building around the initial position and correcting the initial position using the information
A method for estimating a location using GIS information.
9. The method of claim 8, wherein determining the final position comprises:
If the position of the satellite is the LOS position at the candidate position, calculates the probability density of the GPS signal by applying the SNR value of the specific GPS signal to the Rician Distribution Model at the candidate position, Calculating the probability density of the GPS signal by applying an SNR value of a specific GPS signal to a Rayleigh Distribution Model
A method for estimating a location using GIS information.
10. The method of claim 9, wherein determining the final position comprises:
Multiplying the probability density of a plurality of GPS signals corresponding to individual candidate positions to calculate a probability of being a current position and determining a candidate position having the greatest probability of the current position as a final position
A method for estimating a location using GIS information.

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