KR20120039250A - Differential gps using range correction mapping - Google Patents

Abstract

PURPOSE: A satellite navigation enforcement method using location area mapping of measured value correction information is provided to reduce costs required for new module purchase in order to improve performance by removing effective errors of a low-price type satellite navigation module. CONSTITUTION: A navigation satellite orbit information receiving module(601) receives satellite orbit information and calculates the location of a visible satellite. An observation matrix configuring module(603) constitutes an observation matrix by calculation of a view line vector based on geometric relation between a user and a satellite. A location area projecting module(605) constitutes correlation equation between location-based correction information and measured value correction information. A location-based correction information generating module(606) generates the location-based correction information and removes errors of the location-based correction information through differential.

Description

Satellite GPS reinforcement method using location area mapping of measured value correction information {Differential GPS using Range Correction Mapping}

The present invention relates to a method for reinforcing satellite navigation in a location area in which measured value correction information used for improving the accuracy of satellite navigation is projected and subdivided into the location area.

Global Navigation Satellite System (GNSS), commonly known as Global Positioning System (GPS), is a satellite-based, global radio navigation system that allows users with a module to receive signals from satellites anytime, anywhere. Irrespective of their position, it is an ideal system to determine their position with high positional accuracy of about several tens of meters.

To determine the position using satellite navigation, the navigation equation of [Equation 1] is used. The satellite position-related information included in the navigation data is analyzed to determine the position vector of the satellite, and the position equation is calculated by constructing the observation equation for the measured satellites.

[Equation 1]

Error components included in satellite navigation measurements include errors in satellite orbit and time estimates, errors in the ionosphere and convective layers, and multipath and receiver noise errors. Among these, multipath and receiver noise errors are determined by the characteristics and environment of the receiver, but the remaining error components are called common errors because their effects are similar within a short range within the same time zone.

The satellite navigation reinforcement system (DGNSS / DGPS, Differential GNSS / GPS) uses the characteristic that the common error between the points within the same time is close to the common point. It is a technique to improve the application and accuracy to 1 ~ 3m level. In general, a method for improving the accuracy of the satellite navigation system includes a measurement area satellite navigation reinforcement method (FIG. 1) and a range area reinforcement method called block shift technique (Range Correction) applying distance correction information for each measurement value of a visible satellite. 3) are divided into two.

The technique using the distance correction information calculates the distance between the reference station 102 and the satellite 101 where the location is accurately known, and then estimates the error components of each satellite through the difference between the measured values received from the reference station and the data. The error is eliminated by transmitting the correction information 104 through the communication 105 to differential the distance based on all measurements received by the user 103. There are two methods of generating correction information, a scalar method that calculates an error amount regardless of an error factor, and a vector method that decomposes components by an error factor. Calm down in the domain.

[Equation 2]

After the user 103 of the reinforcement system using the distance correction information receives the measured value correction information 201, the user 103 through the difference as shown in [Equation 2] to the measured value obtained from the raw data extraction module 202 (203). An improved position result may be obtained by removing an error in a distance area and substituting 204 the measured value from which the error is removed into the observation equation of Equation 1.

)를 구한 후, 기존에 정확히 측량된 위치(

)와의 차분을 통해 위치영역에서의 오차 벡터(

)(304)를 계산하여 이를 보정정보로 적용하는 방식이다. 근거리 내에 배치된 기준국과 사용자(303)의 경우 동시간에 동일 위성 조합이라면 측정치 오차가 위치에 투영되는 오차 벡터 상관성이 높으므로, 기준국에서 생성된 위치 오차 벡터를 사용자에서 산출한 위치(402)에서 차분함(403)으로써 [수학식 4]와 같이 정확도가 향상된 위치 결과를 산출(404)한다.The position correction information technique combines the currently received navigation satellite 301 signal with a position at the reference station 302.

), Then use the existing

Error vector in the location region

) 304 is calculated and applied as correction information. In the case of the reference station and the user 303 disposed within a short distance, if the same satellite combination is the same at the same time, the error vector correlation of the measurement error is projected to the position is high, and thus the position calculated by the user at the position error vector generated by the reference station 402. By subtracting 403, the position result of which the accuracy is improved as shown in Equation 4 is calculated (404).

&Quot; (3) "

&Quot; (4) "

Of the conventional satellite navigation reinforcement system, the method using the position correction information can be intuitively used by general users who do not have a professional understanding of the navigation algorithm, and can be easily applied to the receiver which cannot access the raw data. . However, when the reference station and the user's visible satellites are different, the error components of the combination of satellites are different from each other so that the user can be used only when the user is very close to the reference station and the same satellite visibility is secured. Since this is a very difficult condition to be met in reality, the location area reinforcement system is only described conceptually and is generally rarely used.

On the other hand, the satellite navigation reinforcement system using the distance correction information is currently used because the user can selectively apply the correction information generated by the reference station according to his situation. Most reinforcement systems in use use it. However, this method is also limited to use because it can be implemented only in the receiver for the reinforcement system to provide the raw data and there is a limitation that the accuracy cannot be improved only by the predetermined location information. In particular, when a low-cost satellite navigation receiver module using a chip unit provides only a location result such as GPGGA of the National Marine Electronics Association (NMEA), it is impossible to remove an error included in the calculated location result.

The present invention intends to propose a method for improving position accuracy even for a satellite navigation receiving module that does not provide raw data.

The present invention for achieving the above object relates to a technology that can improve the position output accuracy of about 15m to within a level of 1 ~ 3m even for satellite navigation receiving module that does not provide raw data, the existing distance-based satellite navigation The mapping of the correction information to the position-based correction information is the core of the present invention.

The system for the implementation of the proposed invention includes data communication capable of receiving distance-based satellite navigation correction information and satellite orbit information, software for generating location-based satellite navigation correction information, and related hardware including a reference station and a user receiving module. It is composed. It acquires satellite orbit information through data communication, calculates the position of the satellite, and constructs the observation matrix through the relationship with the user position provided by the receiving module. The distance-based correction information (measurement correction information) generated at the reference station and received through data communication is multiplied by the pseudo inverse of the calculated observation matrix, thereby generating location-based correction information. The user error is eliminated by subtracting this in the form of a vector to the user position provided by the receiving module.

In other words, the present invention relates to a satellite navigation reinforcement method for improving the accuracy of satellite navigation, to obtain the position of the navigation satellite by receiving the orbit information of the navigation satellite 501, the user's satellite navigation alone positioning module 602 Determining a user location through a tenth step; A step 20 of constructing an observation matrix by calculating a gaze vector of the navigation satellite based on a geometric relationship between the position of the navigation satellite and a user position; Generating position-based correction information from a correlation between the measurement correction information including the observation matrix and the position-based correction information; And determining the user location from which the error is removed by subtracting the location-based correction information from the user location determined by the satellite navigation single positioning module 602 of the user.

When applying the location area satellite navigation reinforcement method through the location-based correction information mapping derived from the present invention, it is possible to effectively eliminate the error of the low-cost satellite navigation module that users have installed, so that it is necessary to purchase a new module for performance improvement. It can contribute to cost reduction. And it is possible to reduce the cost and popularize location-based high-end service equipment, including surveying, which was possible only with expensive equipment. In addition, the performance of low-cost satellite navigation modules can be effectively improved to high-class receivers, and overall industrial growth is expected in the field of LBS (Location Based Service), Information Technology (IT), and Intelligent Transportation System (ITS).

1 is a conceptual diagram of a measurement-based satellite navigation reinforcement system of the conventional satellite navigation correction method.
2 is a conceptual diagram of a measurement-based satellite navigation reinforcement system which is a conventional satellite navigation correction method.
3 is a conceptual diagram of a configuration of a satellite navigation system based on location, which is a conventional satellite navigation correction method.
4 is a conceptual diagram of a position-based satellite navigation reinforcement system which is a conventional satellite navigation correction method.
5 is a block diagram of a satellite navigation system based on location using measurement-based correction information according to an embodiment of the present invention.
6 is a detailed algorithm conceptual diagram of the measurement correction information location region mapping module according to the present invention;

Hereinafter, a satellite navigation reinforcement system using position area projection and difference of measured value correction information according to the present invention will be described in detail with reference to the accompanying drawings. Advantages and features of the present invention and methods for achieving them will be apparent with reference to the embodiments described below in detail with the accompanying drawings.

However, the present invention is not limited to the embodiments disclosed below, but will be implemented in various forms, and only the present embodiments are intended to complete the disclosure of the present invention, and the general knowledge in the art to which the present invention pertains. It is provided to fully convey the scope of the invention to those skilled in the art, and is only defined by the scope of the claims of the invention. Like reference numerals refer to like elements throughout.

FIG. 5 is a diagram illustrating a configuration of a location area satellite navigation reinforcement system in which error is offset after mapping measurement-based satellite navigation correction information to location-based satellite navigation correction information.

As shown in FIG. 5, the reinforcement system for implementing the present invention includes a navigation satellite 501 for transmitting a navigation signal, a reference base satellite navigation reinforcement system reference station 502, a data communication 505 for transmitting correction information, Satellite orbit information transmission server 508, satellite orbit information transmission data communication 509, the user 503 is configured.

The above components include not only the existing infrastructure but also new types of components that perform the same functions. In particular, the navigation satellite 501 is a satellite, such as GPS, GLONASS, Galileo, QZSS, COMPASS, Beidou, Pseudolite, two-way Pseudolite, which transmits the same or similar signals as the navigation satellite, And distance-based positioning system signal sources.

The measurement-based satellite navigation correction information 504 generated by the measurement-based satellite navigation reinforcement system reference station 502 is a scalar type such as PRC (Pseudo-Range Correction) or Carrier Phase Correction (CPC) of Local DGNSS, and SBAS (US). Satellite-based Augmentation System (WAS) Includes all types of correction information that can be converted into distance-domain correction information when applied to users, such as a vector form such as a wide area augmentation system (WAAS), or a form based on a model equation.

FIG. 5 illustrates only the case where the measurement correction information location area mapping module 506 is included in the user 503, but is separated from the user 503, or included in the reference station 502 or the server 508. Technically, all embodiments of the same type are included in the present invention.

In the present embodiment, only the measurement-based satellite navigation correction information 504 and the satellite orbit information transmitted from the measurement-based satellite navigation enhanced system reference station 502 through the communication channels 505 and 509 are described. This also applies to measurement-based satellite navigation correction information and satellite orbit information given to users regardless. In addition, the satellite orbit information includes all the absolute or relative position of the satellite, and various parameters for calculating such a position.

The measurement-based satellite navigation correction information 504 and the satellite orbit information given to the user are converted into the position-based satellite navigation correction information 507 through the measurement correction information location region mapping module 506, and then the position of the user 503. Accuracy is improved by eliminating errors.

The measurement-based satellite navigation correction information is also referred to simply as measurement correction information.

)를 산출하여 관측 행렬 H를 구성한다(603).FIG. 6 is a conceptual diagram of a user 503 application method of location-based correction information generated by the measurement correction information location region mapping module 506. The satellite orbit information is received by the navigation satellite orbit information receiving module 601 to obtain the position of the visible satellite. The gaze vector of [Equation 1] based on the geometric relationship between the user and the satellite based on the obtained position of the satellite and the position determined by the satellite navigation single positioning module 602 of the user 503 (

) Is constructed to form the observation matrix H (603).

In the conventional satellite navigation reinforcement system, the process of removing the measurement error through [Equation 2] and substituting it into [Equation 1] can be described as in [Equation 5].

[Equation 5]

&Quot; (6) "

)와 위치기반 보정정보(

)간의 상관식이 구성되고 이에 근거하여 측정치 보정정보의 위치영역 투영 모듈(605)이 구성된다. Measured value correction information according to Equation 6 above (

) And location-based correction

) Is constructed, and based on this, the position area projection module 605 of the measurement correction information is constructed.

)를 구할 수 있다. 아래의 수식은 위치기반 보정정보(

)를 도출하기 위한 일부 예로써, [수학식 6]의 식에 근거한 모든 도출 방법을 포함한다.By using the least-squares method shown in Equation 7 or Equation 8, the position-based correction information (Equation 6)

) Can be obtained. The following formula is based on location-based correction information (

Some examples to derive) include all derivation methods based on the equation (6).

[Equation 7]

[Equation 8]

)를 생성(606)한 이후, [수학식 4]에 사용자의 위성항법 단독 측위 모듈(602)의 결과값(

)을 대입하여, 차분을 통한 위치오차 제거 모듈(607)을 통해 오차가 제거된 사용자 위치(

)를 결정(608)한다.
Location-based correction information (through the above process)

After generating 606, the resultant value of the user's satellite navigation single positioning module 602 is expressed in [Equation 4].

), The user position (the error is removed through the position error removal module 607 through the difference)

(608).

501: navigation satellite
502 reference station based satellite
503: user
504: measurement based satellite navigation correction information
505: data communication for correction information transmission
506: measurement value correction information position area mapping module
507: position-based satellite navigation correction information
508: satellite orbit information transmission server
509: Data communication for satellite orbit information transmission
601: navigation satellite orbit information receiving module
602: satellite navigation single positioning module
603: observation matrix configuration module
604: satellite navigation measurement based correction information receiving module
605: position area projection module of measured value correction information
606: location-based correction information generation module
607: Position error removal module by difference
608: positioning module

Claims (6)

The present invention relates to a satellite navigation reinforcement method for improving the accuracy of satellite navigation.
Receiving a trajectory information of the navigation satellite 501 to obtain a location of the navigation satellite, and determining a user location through the user's satellite navigation single positioning module 602;
A step 20 of constructing an observation matrix by calculating a gaze vector of the navigation satellite based on a geometric relationship between the position of the navigation satellite and a user position;
Generating a location-based correction information by projecting onto a location area from a correlation between the measurement correction information including the observation matrix and the location-based correction information;
Determining a user position from which an error is removed by subtracting the position-based correction information from the user position determined by the satellite navigation single positioning module 602 of the user;
Satellite navigation reinforcement method using the location region mapping of the measured value correction information, characterized in that consisting of. In claim 1,
The observation matrix of step 20 is

here
H: observation matrix

: line of sight of the i-th satellite
Satellite navigation reinforcement method using the location region mapping of the measured value correction information. In claim 1,
The correlation between the measured value correction information and the position-based correction information in the thirtieth step is

here

: Measurement correction information
H: observation matrix

Location-based correction information
Satellite navigation reinforcement method using the location region mapping of the measured value correction information. 4. The method of claim 3,
Location-based correction

) By the least-squares method

The satellite navigation reinforcement method using the position area mapping of the measurement value correction information, characterized in that obtained by projecting the measurement value correction information to the position area in the equation. 4. The method of claim 3,
Location-based correction

) By the least-squares method

here
R; Measurement correction information

Covariance matrix of
Satellite navigation reinforcement method using the location region mapping of the measured value correction information. The method of claim 4 or 5,
The user location where the error is removed is

here

: User location with error removed

: User location determined in the satellite navigation single positioning module 602

Location-based correction information
Satellite navigation reinforcement method using the location region mapping of the measurement correction information, characterized in that obtained from the correlation.

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