KR101617033B1 - Global standard point positioning apparatus using multi global satellite positioning systems and the method thereof - Google Patents

Global standard point positioning apparatus using multi global satellite positioning systems and the method thereof Download PDF

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KR101617033B1
KR101617033B1 KR1020150130248A KR20150130248A KR101617033B1 KR 101617033 B1 KR101617033 B1 KR 101617033B1 KR 1020150130248 A KR1020150130248 A KR 1020150130248A KR 20150130248 A KR20150130248 A KR 20150130248A KR 101617033 B1 KR101617033 B1 KR 101617033B1
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satellite
receiver
distance
error
positioning
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최병규
조창현
조정호
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한국 천문 연구원
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    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S19/00—Satellite radio beacon positioning systems; Determining position, velocity or attitude using signals transmitted by such systems
    • G01S19/01—Satellite radio beacon positioning systems transmitting time-stamped messages, e.g. GPS [Global Positioning System], GLONASS [Global Orbiting Navigation Satellite System] or GALILEO
    • G01S19/03—Cooperating elements; Interaction or communication between different cooperating elements or between cooperating elements and receivers
    • G01S19/07—Cooperating elements; Interaction or communication between different cooperating elements or between cooperating elements and receivers providing data for correcting measured positioning data, e.g. DGPS [differential GPS] or ionosphere corrections
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S19/00—Satellite radio beacon positioning systems; Determining position, velocity or attitude using signals transmitted by such systems
    • G01S19/01—Satellite radio beacon positioning systems transmitting time-stamped messages, e.g. GPS [Global Positioning System], GLONASS [Global Orbiting Navigation Satellite System] or GALILEO
    • G01S19/03—Cooperating elements; Interaction or communication between different cooperating elements or between cooperating elements and receivers
    • G01S19/08—Cooperating elements; Interaction or communication between different cooperating elements or between cooperating elements and receivers providing integrity information, e.g. health of satellites or quality of ephemeris data

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Abstract

The present invention relates to an integrated global positioning device using a multi-satellite navigation system and a method thereof. The device comprises: a receiving unit configured to classify and output satellite signals per a satellite navigation system; a satellite-receiving unit distance operating unit configured to operate and output a satellite-receiving unit distance; a satellite-receiving unit correction distance operating unit configured to operate and output a satellite-receiving unit correction distance; a residual extracting unit configured to extract the difference between the satellite-receiving unit distance and the satellite-receiving unit correction distance as a residual; a time and coordinate converting unit; and a positioning information extracting unit. Therefore, the device can improve positioning accuracy, reliability, and satellite availability of a global navigation satellite system (GNSS).

Description

TECHNICAL FIELD [0001] The present invention relates to a global positioning system using a multi-satellite navigation system,

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a global positioning apparatus and method, and more particularly, to GPS, Galileo, GLONASS. Satellite navigation system including one or more satellite navigation systems such as BeiDou, QZSS, etc., and to a method for integrating global positioning using the multi-satellite navigation system .

The Global Positioning System (GPS) in the United States is a global satellite navigation system that has been operating for over 30 years, providing users with useful location and visual information. GPS signals are used in various fields because they can be received anytime and anywhere regardless of the weather. In addition, GPS is becoming an important social public infrastructure due to increasing demand in defense and private sectors.

As the value of economic, social and military utility of GPS becomes more prominent, Russia has established and operated a system called GLONASS, and the European Union and China are building a global satellite navigation system called Galilleo and BeiDou. GPS is currently in operation for 31 units, and Russia's GLONASS has been operating all 24 satellites since the end of 2011. Galileo of the European Union will be composed of 30 medium orbit satellites, and six navigation satellites are currently in operation. China's BeiDou satellite is currently in operation with 14 units and plans to launch 35 satellites by 2020 (BeiDou ICD, 2013). Countries have recently been competing to build systems and improve performance in order to secure leadership in satellite navigation systems.

Japan is developing a regional satellite navigation system called the Quasi-Zenith Satellite System (QZSS), and currently has one (IS-QZSS, 2014). QZSS is expected to play an important role in ensuring positioning stability in the city center while maintaining high elevation angle with the satellite covering the Asia-Oceania region.

The Global Navigation Satellite System (GNSS) enables more accurate and precise information such as geodetic, navigation, and time information. Since 2020, it is expected to receive at least 35 GNSS navigation signals in Asia-Oceania.

Accordingly, Korean Patent Laid-Open Publication No. 10-2014-0040316 calculates the coordinates of the distance and the center position between the moving object and the reference position using the moving object camera and the reference position information, compares the coordinates with the GNSS position information, and corrects the GNSS coordinate information A GNSS coordinate information correction method using a vision system and a satellite navigation apparatus according to the method.

Further, Korean Patent Registration No. 10-0946929 estimates the present time and position to generate the leaveless information, and then determines an operation mode related to navigation information generation as a hot start mode based on the generated leaveless information To shorten the TTFF and reduce the power consumption by reducing the connection time with the GNSS satellite and a method of operating the GNSS navigation receiver.

Thus, various techniques for the application of GNSS positioning systems are being provided.

Therefore, in order to improve the positioning accuracy, reliability, and satellite availability of GNSS, it is necessary to correct the propagation delay and the time error accurately after integrating the received signal information from multiple navigation satellite systems It is required to provide a global positioning apparatus and method using a multi-satellite navigation system that can improve the positioning accuracy, reliability, and satellite availability of a GNSS positioning system .

Korean Patent Publication No. 10-2014-0040316 Korean Patent No. 10-0946929

Therefore, the present invention calculates and analyzes the bias generated by the combination of systems, and eventually combines GPS / GLONASS / BeiDou / QZSS to determine the positioning accuracy, reliability, satellite availability The present invention also provides a global positioning apparatus and method using the multi-satellite navigation system that can improve the positioning accuracy and the like.

According to another aspect of the present invention, there is provided a global integrated positioning system using a multi-satellite navigation system, comprising: a receiver for detecting frequencies of satellite signals observed for a plurality of satellite navigation systems and classifying and outputting satellite signals for each satellite navigation system; A satellite-receiver distance calculator for calculating and outputting a satellite-receiver distance (P i j , j is a GNSS satellite identifier, i is an i-th frequency) using the time information of the satellite signal output from the receiver; A satellite-receiver correction distance calculator for calculating and outputting a satellite-receiver correction distance S i j using the geometric distance of the receiver and the satellite; A residual extracting unit for extracting a difference (P i j - S i j ) between the satellite-receiver distance and the satellite-receiver correction distance as residuals; A time and coordinate converter for converting a time system and a coordinate system of each of the plurality of satellite navigation systems into a reference time system and a reference coordinate system of a satellite navigation system selected as a reference satellite navigation system in a plurality of satellite navigation systems; And a positioning information estimating unit estimating positioning information including position information of the receiving unit using the residual, the reference time frame, and the reference frame coordinate information.

The satellite-receiver correction distance calculation unit, a geometric distance between the satellite and the receiver (geometry range) (ρ i j ), the satellite clock error satellite clock error delay distance (cdT j), convective layer delay error by a (dT j) (d j trop), i the second ionospheric delay error of the GNSS satellite with a frequency (d j iono / Li), receiver noise and multipath error (ε j Pi) the operation after the first satellite-receiver calibration distance (S i ρ i j = 1 j -cdT j + d j d j + trop iono / Li + ε j Pi) and a derived, cdt delay distance by the receiver clock error (dtj) derived by the position information estimation (j) and after receiving the input bias (ISB j) between the system of the second satellite-receiver distance correction (Si j 2) = j ρ i + j + cdt ISB -cdT j j + d j d j + trop iono / Li + ε j P i ) of the received signal.

Where j is the GNSS satellite identifier, i is the i th frequency, ρ i j is the geometry range between the satellite and receiver, dt j is the receiver clock error, dT j is the satellite clock error, ISBj (Intersystem biases) the system to-bias, c is the speed of light, d j trop convective layer delay error, d j iono / Li is the i-th ionospheric delay error of the GNSS satellite with a frequency, ε j P i is the receiver noise and multipath error.

The ionospheric delay error ( dj iono / Li ) of the GNSS satellite having the i-th frequency can be calculated by (f GPSLi / f GLSSL i) 2 * Klob.

Where f GPSLi is the GPS Li frequency, f GLSSLi is GPS Li, GLonASS Li, Bi of BeiDou Bi, and Li frequency of QZSS, and Klob is the ionospheric delay value calculated through the Klobuchar model.

The residual extractor may be configured to derive a first residual (P i j - S i j 1) and a second residual (P i j - S i j 2).

The time and coordinate converter may be configured to convert a time system and a coordinate system of the received satellite signals of the multi-satellite navigation system into a reference time system and a reference coordinate system of the reference satellite navigation system.

The positioning information estimation unit is configured to estimate positioning information including at least one of position information, a clock error, and a system-to-system bias by applying a weighted least squares method.

The positioning information (

Figure 112015089536089-pat00001
),

Figure 112015089536089-pat00002

Figure 112015089536089-pat00003
,

Figure 112015089536089-pat00004
,

Figure 112015089536089-pat00005
,

Lt; / RTI >

Here, H denotes a design matrix, W denotes a weighted matrix according to a satellite elevation angle,

Figure 112015089536089-pat00006
G is GPS, R is GLONASS, C is BeiDou, Q is QZSS, and E is an elevation angle.

Multiple global integration positioning method using a satellite positioning system of the present invention for achieving the above object, the residual extracting additional satellites using the time information of the satellite signal from the receiver-receiver distance (P i j, j is GNSS I is the i-th frequency), and the first satellite-receiver correction distance S i j 1 = ρ i j -cdT j + d j trop + d j iono / Li + ε j P i) with a difference between the first residual-first residual extracting process of extracting the ((P i j S i j 1); clock and the coordinate converting part of the received satellite signals in the multiple satellite navigation system A time and coordinate conversion process of converting a time system and a coordinate system into a reference time system and a reference coordinate system of the reference satellite navigation system, a positioning information estimation unit applying a weighted least squares method to the first residual, More than one A first positioning information estimating step of estimating first positioning information including a delay time (cdt j ) due to a receiver time clock error (dt j ) derived from the first positioning information and an inter-system bias (ISB j And the second satellite-receiver correction distance S i j 2 = ρ i j + cdt j + ISB j -cdT j + d j trop + d j iono / Li + ε j Pi) A second residual extraction step of deriving a second residual (P i j - S i j 2); And the positioning information estimation unit estimates second positioning information including at least one of position information, a clock error, and a system-to-system bias by applying a weighted least squares method to the second residual, and outputs the second positioning information as positioning information including the position of the receiving unit And a second positioning information estimation process.

Where j is the GNSS satellite identifier, ρ i j is the geometry range between the satellite and receiver, dt j is the receiver clock error, dT j is the satellite clock error, ISB j is the inter-system bias, c is the speed of light, d j trop convection zone) delay error, d j iono / Li is i ionospheric delay error of the GNSS satellite having a first frequency, ε j Pi is the receiver noise and multipath error.

The global combined positioning method may be configured to repeat the second residual information extraction process and the second positioning information estimation process after the second positioning information estimation process is performed until the positioning information satisfies predetermined accuracy .

The present invention having the above-described configuration provides an effect of significantly improving the accuracy of the positioning information of the receiver by improving the accuracy of the electronic delay compensation in the integrated positioning process using the multi-satellite navigation system.

1 is a block diagram of a global positioning apparatus (hereinafter referred to as an integrated positioning apparatus 100) using a multi-satellite navigation system according to an embodiment of the present invention.
FIG. 2 is a diagram showing a musical composition according to a satellite navigation system constituting a GNSS system; FIG.
3 is a flowchart showing a process of a global positioning method using a multi-satellite navigation system according to an embodiment of the present invention.
FIG. 4 is a graph showing the number of visible satellites and the sum of all visible satellites according to the satellite navigation system constituting the GNSS over time in the MKPO GNSS reference station.
5 is a graph showing a result of performing standard point positioning using only a single frequency code.
FIG. 6 is a graph showing the horizontal position error shown in FIG. 5 and the horizontal position error calculated using only the GPS in a two-dimensional plane, respectively.
7 is a graph showing the RMS value of the position error calculated through the experimental group.
8 is a table showing the results shown in FIG. 7 and the daily average position error according to each combination.
9 is a graph showing ISB calculation values over time using data observed by the Trimble NetR9 receiver operating in the MKPO GNSS reference station.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in more detail with reference to the accompanying drawings showing preferred embodiments of the present invention.

In the following description of the present invention, detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention rather unclear.

The embodiments according to the concept of the present invention can be variously modified and can take various forms, so that specific embodiments are illustrated in the drawings and described in detail in the specification or the application. It is to be understood, however, that the intention is not to limit the embodiments according to the concepts of the invention to the specific forms of disclosure, and that the invention includes all modifications, equivalents and alternatives falling within the spirit and scope of the invention. Also, the word "exemplary" is used herein to mean "serving as an example, instance, or illustration." Any aspect described herein as "exemplary " is not necessarily to be construed as preferred or advantageous over other aspects.

It is to be understood that when an element is referred to as being "connected" or "connected" to another element, it may be directly connected or connected to the other element, . On the other hand, when an element is referred to as being "directly connected" or "directly connected" to another element, it should be understood that there are no other elements in between. Other expressions that describe the relationship between components, such as "between" and "between" or "neighboring to" and "directly adjacent to" should be interpreted as well.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The singular expressions include plural expressions unless the context clearly dictates otherwise. In this specification, the terms "comprises ", or" having ", or the like, specify that there is a stated feature, number, step, operation, , Steps, operations, components, parts, or combinations thereof, as a matter of principle.

1 is a block diagram of a global positioning apparatus (hereinafter referred to as an integrated positioning apparatus 100) using a multi-satellite navigation system according to an embodiment of the present invention.

1, the integrated positioning apparatus 100 includes a reception unit 110 having an antenna 111, a satellite-reception unit distance calculation unit 120, a satellite-reception unit correction distance calculation unit 130, A time and coordinate transforming unit 150, and a positioning information estimating unit 160.

The receiver 110 detects frequencies of satellite signals observed for each of a plurality of satellite navigation systems and classifies and outputs satellite signals for each satellite navigation system.

GPS uses two L-band (L1 ~ 1,575.42MHz, L2 ~ 1,227.60MHz) and GLONASS has two frequency bands fL1 = (1602 + n * 0.5625) MHz and fL2 = (1246 + n * 0.4375) MHz to provide information to the user (GLONASS ICD, 2008). Where n is the frequency channel number. In addition, BeiDou satellite transmits three frequencies (B1 ~ 1,561,098MHz, B2 ~ 1,207,140MHz, and B3 ~ 1,268,520MHz) (BeiDou ICD, 2013) and QZSS uses the same signal as GPS.

In the description of the embodiment of the present invention, a GPS is used as a reference satellite navigation system, and an L1 C / A (Coarse / Acquisition) code, a GLONASS L1 code of GPS, a BeiDou B1 Code, and the L1 code of QZSS.

In the present invention, the observation equation using the GNSS code value is expressed by Equation (1).

Figure 112015089536089-pat00007

Here, Pi j is the satellite-receiver distance, RHS is a satellite-receiver is corrected distance (Si j) is a j i + cdt j + ISB ρ j -cdT j + d j d j + trop iono / Li + ε j Pi) , ρ i j is the geometric distance (geometry range), dt j between the satellite and the receiver includes a receiver clock error, dT j is the satellite clock error, ISBj (intersystem biases) are intersystem bias, c is the speed of light, d j trop convection layer delay error, dj iono / Li is the ionospheric delay error of the GNSS satellite with the ith frequency, ε j Pi is the receiver noise and multipath error, j is the GNSS satellite identifier, and i is the i th frequency.

At this time, since the reference satellite navigation system is GPS in the embodiment of the present invention, the convective layer delay error d j trop is applied to the calculation method of the convection layer delay error of the GPS model.

The satellite-receiver distance calculator 130 calculates a satellite-receiver distance (P i j , j is a GNSS satellite identifier and i is an i-th frequency) using the time information of the satellite signal output from the receiver 110 And outputs it. The satellite-receiver distance (P i j ) is obtained by multiplying the arrival time of the radio wave by the speed of light using the difference between the time information included in the satellite signal and the time information of the receiver.

The satellite-receiver correction distance calculator 140 is configured to calculate and output the satellite-receiver correction distance S i j using the geometric distance (ρ i j ) between the receiver and the satellite.

For this, the satellite-receiver correction distance calculator 140 calculates a geometry range (ρ i j ) between the satellite and the receiver, a satellite clock error delay distance (cdT j ) based on the satellite clock dT j , the convective layer delay error (d trop j), ionospheric delay error of the GNSS satellite that has the i-th frequency (d j iono / Li), receiver noise and multipath error (ε j P i) is extracted by calculation. Where j is the GNSS satellite identifier and i is the i-th frequency.

The ionospheric delay error ( dj iono / Li ) of the GNSS satellite having the i-th frequency is obtained by Equation (2).

Figure 112015089536089-pat00008

Where f GPSLi is the GPS Li frequency, f GLSSLi is GPS Li, GLonASS Li, Bi of BeiDou Bi, and Li frequency of QZSS, and Klob is the ionospheric delay value calculated through the Klobuchar model.

The satellite-receiver correction distance calculator 140 also derives the satellite-receiver correction distance S i j by applying the calculated information. The derived the satellite-receiver distance correction (S i j) is the first satellite-receiver distance correction (S i j = 1 j ρ i -cdT j + d j d j + trop iono / Li + ε j Pi) and The second satellite-receiver correction distance (S i j 2) = ρ i j + cdt j + ISB j -cdT j + d j trop + d j iono / Li + ε j Pi.

The first satellite-receiver distance correction (S i j = 1 j ρ i -cdT j + d j d j + trop iono / Li + ε j Pi) is the geometric distance between the satellite and the receiver (geometry range) (ρ i j), satellite clock error delay distance (cdT j), convective layer delay error (d j trop), ionospheric delay error of the i GNSS satellite having a second frequency according to the satellite clock error (dT j) (d j iono / Li ), The noise of the receiver and the multipath error (ε j Pi) are applied.

The second satellite-receiver correction distance (S i j 2 = ρ i j + cdt j + ISB j -cdT j + d j trop + d j iono / Li + ε j Pi) The delay time (cdt j ) due to the clock error (dt j ) and the inter-system bias (ISB j ) are calculated and become the desired first positioning information.

The residual extraction section 150 is a satellite is configured to extract the - (S P i j i j) by the residual difference between the reception calibration distance (S i j) - receiver distances (P i j) and the satellite.

At this time, the residual is satellite-car receiver of correcting distance (S i j = 1 j ρ i -cdT j + d j d j + trop iono / Li + ε j Pi) - receiver distances (P i j) of the first satellite first residual (P i j - S i j 1) and the satellite-receiver distance (Pij) and the second satellite-receiver distance correction (S i j i j + 2 = ρ j + cdt ISB -cdT j j + d j (P i j - S i j 2), which is the difference between trop + d j iono / Li + ε j Pi.

The time and coordinate conversion unit 150 is configured to convert a plurality of time-of-satellite systems and a coordinate system into a reference time system and a reference time system of a satellite navigation system selected as a reference satellite navigation system in a plurality of satellite navigation systems.

The GPS and QZSS use the GPS time (GPST), the BeiDou use the BeiDou Time (BDT) and the 14 second difference from the GPST (BeiDou ICD, 2013). GLONASS also uses Coordinated Universal Time (UTC).

The reference coordinate system is the World Geodetic System 84 (WGS 84) used in the GPS system. BeiDou and QZSS use reference coordinate system called China Geodetic Coordinate System 2000 (CGCS2000) and Japan Satellite Navigation Geodetic System (JGS), respectively.

In the embodiment of the present invention, the GPS is set as the reference satellite navigation system. Therefore, in the embodiment of the present invention, it is assumed that CGCS2000 and JGS are the same as WGS84, and the reference coordinate system of GLONASS's Parametric Zemli 1990 (PZ-90) is converted into WGS84 by applying [Equation 3].

Figure 112015089536089-pat00009

Here, (x ', y', z ') is the WGS84 reference coordinate value, and (x, y, z) is the PZ-90 reference coordinate value. To convert between two reference frame 7 coefficients, that is {T 1, T 2, T 3, D, R 1, R 2, R 3} The essential factor, and the value {T 1, T 2 , T 3 } is {0.07m, 0.00m, 0.77m}, D is -3 parts per billion, and {R 1 , R 2 , R 3 } is {-19, -4, 353}. The units of {R 1 , R 2 , R 3 } are all mili-arc seconds.

2 is a diagram showing the specifications of a satellite navigation system constituting the GNSS system.

In the table of FIG. 2, reference time system and reference coordinate system, maximum number of satellites (current number of available satellites), satellite orbital plane, orbit inclination angle, average altitude of satellites, and rotation period of satellites are shown together.

The positioning information estimating unit 160 estimates positioning information including position information of the receiver using the residual, the reference time, and the reference coordinate system information

Figure 112016010694528-pat00010
). Specifically, the positioning information includes position information of a receiving unit, a clock error, and bias information between systems.

The positioning information (

Figure 112015089536089-pat00011
) Is obtained by the following equations (4) to (7).

Figure 112015089536089-pat00012

Figure 112015089536089-pat00013

Figure 112015089536089-pat00014

Figure 112015089536089-pat00015

In Equation 5 to 7, H is the design matrix (Design matrix), the (x 0, y o, z 0) are the coordinates of the GPS based navigation system, (X, Y, Z) are each superscript The coordinates of the corresponding satellite navigation system coordinate system, W is a weighted matrix according to the satellite elevation angle,

Figure 112015089536089-pat00016
(Res) vector, G is GPS, R is GLONASS, C is BeiDou, Q is QZSS, and E (Elevation) is an elevation angle.

The positioning information as a final solution obtained by the above-mentioned [Expression 4] to [Expression 7] is expressed by [Expression 8].

Figure 112015089536089-pat00017

Here, Ux, Uy, and Uz are user's position information, dt is the receiver clock error, ISB GPS-GLO is the system bias between GPS and GLONASS, and ISB GPS-BDS is the system bias between GPS and BeiDou.

The second satellite-receiver correction distance S2, which is more accurate by applying the receiver time offset dt and the inter-system bias ISB of the positioning information derived by Equation (8) to [Equation 1] . Thus, a more accurate second residual (

Figure 112016010694528-pat00018
2) is obtained, and by applying this to [Expression 4] to [Expression 7], more accurate positioning information can be obtained. As described above, by repeatedly applying the information obtained by the positioning information estimation unit 150, the accuracy of the positioning information can be increased. Therefore, it is possible to acquire the positioning information of the desired accuracy by setting the number of repetitions at which the positioning information with the desired accuracy is obtained.

3 is a flowchart illustrating a process of a global positioning method using a multi-satellite navigation system according to an embodiment of the present invention.

3, the integrated positioning method of the present invention includes a first residual extraction step S100, a time and coordinate transformation step S20, a first positioning information estimation step S30, a second residual extraction step S40, 2 positioning information estimation process (S50).

First residual extracting process (S100) in the residual extraction section (S140) that, using the time information of the satellite signal output from receiver 110-satellite-receiver distance (P i j, j is a GNSS satellite identifier, i is i times And the first satellite-receiver correction distance (S i j 1 = ρ j -cdT j + d j trop + d j iono / Li + ε Pi), which is generated by correcting the receiving unit and the geometric- And extracts the first residual (P i j - S i j 1).

To this end, the first residual extraction process S100 is performed by calculating the satellite-receiver distance P i j and the first satellite-receiver correction distance S i j 1 of the integrated positioning device 100 S13) and a first residual derivation process (S15).

In the satellite-receiver distance (P i j ) calculation process S11 of the integrated positioning device 100, the satellite-receiver distance calculator 120 calculates the satellite-receiver distance using the time information of the satellite signal output from the receiver 110, (P i j , j is the GNSS satellite identifier, i is the i-th frequency).

In the first satellite-receiver correction distance Sij1 calculation process S13, the satellite-receiver correction distance calculator 130 calculates the first satellite-receiver correction distance S i j 1 (S ij 1) generated by correcting the receiver- = ρ j -cdT j + d j trop + d j iono / Li + ε j Pi).

In the first residual derivation process S15, the residual extractor 140 subtracts the difference between the satellite-receiver distances P i j and the first satellite-receiver correction distances S i j 1 of the integrated positioning device 100 The first residual (

Figure 112016010694528-pat00019
1 = P i j - S i j 1).

In the time and coordinate transformation step S20, the clock and coordinate transformation unit 150 converts the time system and the coordinate system of the received satellite signals of the multi-satellite navigation system into a reference time system and a reference coordinate system of the reference satellite navigation system.

For this, the time and coordinate transformation process S20 includes a reference time transformation process S210 and a reference coordinate transformation process S23.

In the reference time conversion step S21, the time and coordinate transformation unit 150 performs a process of matching the time system of the multi-satellite navigation systems with the time of the reference time system of the reference satellite navigation system.

In the reference coordinate transformation step S23, the time and coordinate transformation unit 150 transforms the coordinates of the multi-satellite navigation systems into the coordinates of the reference coordinate system of the reference navigation system.

In the first positioning information estimation process S30, the positioning information estimator 160 applies the weighted least squares method to the first residual to calculate first positioning information including at least one of position information, a clock error, And performs an estimation process.

The second residual extracting process (S40) in the receiving the residual extraction section 140 inputs the bias (ISB j) between the first delay distance (cdtj) and the system according to the receiver clock error (dtj) derived from one positioning information The second satellite-receiver correction distance (S i j 2 = ρ j + cdt j + ISB j -cdT j + d j trop + d j iono / Li + ε j Pi)

Figure 112016010694528-pat00020
2 = P i j - S i j 2).

To this end, the second residual extraction step S40 includes a second satellite-receiver correction distance S i j2 calculation step S41 and a second residual

Figure 112016010694528-pat00021
2 = P i j -S i j 2) (S43).

In the second satellite-receiver correction distance (S i j 2) calculation process S41, the satellite-receiver correction distance calculator 130 calculates the satellite-receiver correction distance S i j2 by using the receiver clock error dt j derived by the positioning information estimator 160 After receiving the delay distance cdt j and inter-system bias ISBj, the second satellite-receiver correction distance S i j 2 = ρ j + cdt j + ISB j -cdT j + d j trop + d j iono / Li +? J Pi).

The second residual (

Figure 112016010694528-pat00022
2 = P i j -S i j 2) deriving process (S43) in the satellite of the residual extraction section 140 integrates the positioning apparatus 100-receiver distance (P i j) in the second satellite-receiver distance correction (S i j 2) is subtracted from the second residual (
Figure 112016010694528-pat00023
2 = P i j -S i j 2).

In the second positioning information estimation process S50, the positioning information estimation unit 160 applies weighted least squares to the second residual to obtain second positioning information including at least one of position information, clock error, And outputs it as positioning information including the position of the receiving unit.

Also, the global combined positioning method may further include a second positioning information estimation step (S50), a second residual information extraction step (S40), and a second positioning information estimation step (S40), until the positioning information satisfies predetermined accuracy (S50). ≪ / RTI > For this, an error determination process S60 may be further performed to determine whether the estimated positioning information performed in the second positioning information estimation process S50 is within a reference error.

4 to 9 are experimental examples to which the present invention is applied.

In order to analyze the performance of the integrated positioning apparatus of the present invention, observation data received from the MKPO GNSS reference station operated by the Korea Astronomy and Space Science Institute were used. The MKPO GNSS reference station is equipped with a Trimble NetR9 receiver and a TRM59800 antenna. The Trimble NetR9 receiver used in the experiment can receive satellite signals such as GPS, GLONASS, BeiDou, Galileo, and QZSS. In addition, the received observations were converted to Receiver Independent Exchange format (version, "extended 2.11") and used in the preprocessing step. First, we analyzed the changes in the number of visible satellites over time on the Korean peninsula using the observed data.

FIG. 4 is a graph illustrating the number of visible satellites and the sum of all visible satellites according to the satellite navigation system constituting the GNSS according to the passage of time in the MKPO GNSS reference station.

FIG. 4 is a graph showing changes in the number of visible satellites of GPS, GLONASS (GLO), BeiDou (BDS) and QZSS (QZS) over time, Are shown at 15-minute intervals. In FIG. 4, the vertical axis represents the number of visible satellites, and the horizontal axis represents the time when Universal Time (UT) is a reference.

Changes in the number of GPS visible satellites were marked with green diamonds. GPS satellites were observed at up to 12 satellites at UT 3 o'clock, and at least six satellites were observed continuously during the day. GLONASS (GLO) was observed from minimum 4 to maximum 9, and BeiDou (BDS) was marked with red triangle. The number of visible satellites was observed from 7 to 10 at least. Based on the time of observation, it can be seen that China's BDS is observed more than Russian GLO on the Korean Peninsula. In QZSS (QZS), one satellite signal was observed, but no signal was received from 19:00 to 23:00 UT. It was confirmed that this occurred because the integrated positioning apparatus 100 set the elevation cutoff of the satellite at 10 degrees. The number of visible satellites combined with GPS + GLO + BDS + QZS is indicated by gray squares. From at least 19 to 29 satellites, the number of observable satellites varies by time. there was. In the MKPO GNSS reference station, navigation satellites were observed at relatively lower altitudes than at night.

Next, the multi-GNSS observation data received from the MKPO GNSS reference station were processed and the combined positioning results were calculated.

5 is a graph showing a result of performing standard point positioning using only a single frequency code.

As shown in FIG. 5, the positional errors with time are divided into the east direction, the south direction, and the altitude direction component. The absolute position used to calculate the position error was calculated by applying the Static Precise Point Positioning (PPP) method using the GNSS software developed by Korea Astronomy and Space Science Institute. In Fig. 2, the average value of daily position error calculated by the integrated positioning of GPS + GLO + BDS + QZS was calculated as 0.29m, 0.47m, and -0.74m in the east, north, and altitude directions, respectively. In addition, it was found that the average position error of the horizontal (east and south) direction components was smaller than that of the vertical (altitude) direction. The root mean square (RMS) value for the position error is similar to the mean position error, and the positional accuracy of the horizontal direction component is superior.

FIG. 6 is a graph showing a horizontal positional error shown in FIG. 5 and a horizontal positional error calculated using only GPS on a two-dimensional plane, respectively.

In FIG. 6, the abscissa represents the position error of the east direction component, the ordinate axis represents the position error of the north direction component, and the yellow cross mark represents the absolute position (0, 0). The horizontal position error of GPS is indicated by a blue circle, and the horizontal position error of GPS + GLO + BDS + QZS is indicated by red color. As shown in FIG. 6, the integrated positioning results of GPS + GLO + BDS + QZS show that both the positional accuracy and the positional accuracy of the horizontal component are improved as compared with the GPS independent positioning. Especially, it was found that the position accuracy in the north direction was further improved in the horizontal direction component.

In order to compare and analyze the positioning performance through various combinations of navigation satellites, data processing was performed by dividing into five experimental groups. The experimental group is divided into GPS only, GPS + BDS, GPS + GLO, GPS + GLO + BDS and GPS + GLO + BDS + QZSS respectively.

7 is a graph showing the RMS value of the position error calculated through the experimental group.

In FIG. 7, the horizontal axis represents the RMS value for the position error, and the vertical axis represents the east, north, and elevation components. The GPS + BDS combination increased the RMS value of the east direction component by 0.03m, while the RMS value of the north and altitude component components decreased, indicating that the positioning performance was improved as compared with the GPS single location. On the other hand, the GPS + GLO combination showed the largest error in the RMS values of the east and elevation components compared to other experimental groups. And the North direction component showed a small error compared to GPS only and GPS + BDS. These results show that the GPS + GLO combination has an increased RMS value for position error compared to GPS only. In other words, the combination of GPS and GLONASS in the Korean Peninsula did not improve the positioning performance compared with GPS alone. The results presented in this study also tend to agree with previous results. This may be because the noise of the GLONASS satellite signal is large or that the transform coefficients between different reference coordinate systems do not fit well in the mid-latitude peninsula region.

 The combination of GPS + GLO + BDS shows that the RMS values of all directional components are reduced compared to the combination of GPS + GLO. Especially in the altitude direction, the RMS value difference was greatly reduced by about 0.6m. The GPS + GLO + BDS + QZS combination decreased the RMS values of the north and elevation components except for the east component. The addition of one QZS satellite to the GPS + GLO + BDS combination further reduces the RMS value of the altitude component. In other words, the combination of GPS + GLO + BDS + QZS shows that the accuracy of the position of north and elevation components is improved.

  As a result of analyzing the positional accuracy through various combinations, the combination of GPS + GLO showed a relatively low positional accuracy compared to other combinations, whereas the combination of GPS + GLO + BDS + QZS confirmed that positional accuracy was further improved I could.

FIG. 8 is a table showing the results shown in FIG. 7 and the daily average position error according to each combination.

The average position error was found to be relatively higher in the east and altitude direction components compared to other combinations of GPS + GLO combination. This increase in average position error in a particular direction is consistent with an increase in the RMS value. On the contrary, the position error in the north direction showed the smallest error compared to other combinations. In addition, the GPS + GLO + BDS + QZS combination improves the positional accuracy of the north and elevation components, especially in the elevation direction.

The combination of different systems can be expected to improve positional accuracy and position accuracy due to the increase of visible satellites. However, since there is a hardware bias (ISB) between systems, it is necessary to estimate the system bias.

9 is a graph showing ISB calculation values over time using data observed by a Trimble NetR9 receiver operating in the MKPO GNSS reference station.

Since the ISB is a relative value between systems, the characteristics vary from one receiver to another, and there are other differences depending on observations, estimation methods, and visual modeling. SPP and PPP data processing methods.

In FIG. 9, the abscissa indicates the time and the ordinate indicates the ISB (nano-seconds) value. The red triangles and blue squares are ISB changes between GPS and GLONASS (GLO) systems, and ISB changes between GPS and BeiDou (BDS) systems, respectively. The average daily ISB of GPS / GLO is -322.21 ns and GPS / BDS is 39.83 ns. As a result, the average daily ISB between GPS and GLO is relatively large compared to GPS / BDS.

In order to verify the performance of the present invention, the performance of location accuracy according to the combination of navigation satellites was analyzed using multi-GNSS observations received in the Korean Peninsula. In order to compare the performance of location accuracy, data processing was performed by dividing into 5 combinations in total: GPS only, GPS + BDS, GPS + GLO, GPS + GLO + BDS and GPS + GLO + BDS + QZS. As a result of analyzing position error, GPS + GLO combination showed relatively lower positional accuracy compared to other combinations, whereas GPS + GLO + BDS + QZS combination showed improved positional accuracy and positional accuracy . As a result, according to the experimental example of the present invention, it has been confirmed that the combination of many navigation satellites in the Korean peninsula according to the present invention not only increases the number of visible satellites but also improves the user's positional accuracy and positional accuracy.

Further, the present invention has confirmed that the daily average ISB values of GPS / GLO and GPS / BDS are -322.21 ns and 39.83 ns, respectively, by estimating the ISB generated by the combination of systems. From these results, it can be seen that the absolute mean value of ISB of GPS / GLO is larger than the ISB value of GPS / BDS.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments. It will be apparent to those skilled in the art that various modifications may be made without departing from the scope of the present invention. Accordingly, the true scope of the present invention should be determined by the technical idea of the appended claims.

100: Integrated positioning device
111: Antenna

Claims (9)

A receiver for detecting frequency of satellite signals observed for each of a plurality of satellite navigation systems and classifying and outputting satellite signals for each satellite navigation system;
A satellite-receiver distance calculator for calculating and outputting a satellite-receiver distance (P i j , j is a GNSS satellite identifier, i is an i-th frequency) using the time information of the satellite signal output from the receiver;
A satellite-receiver correction distance calculator for calculating and outputting a satellite-receiver correction distance S i j using the geometric distance of the receiver and the satellite;
A residual extracting unit for extracting a difference (P i j - S i j ) between the satellite-receiver distance and the satellite-receiver correction distance as residuals;
A time and coordinate converter for converting a time system and a coordinate system of each of the plurality of satellite navigation systems into a reference time system and a reference coordinate system of a satellite navigation system selected as a reference satellite navigation system in a plurality of satellite navigation systems; And
And a positioning information estimating unit estimating positioning information including position information of the receiving unit using the residual, reference time, and reference coordinate system information.
The satellite-to-reception-signal-correction-distance calculator according to claim 1,
Geometric distance between the satellite and the receiver (geometry range) (ρ i j ), satellite clock error delay distance (cdT j), convective layer delay error (d j trop), i-th frequency of the satellite clock error (dT j) ionospheric delay error of the GNSS satellite having (d j iono / Li), receiver noise and multipath error (ε j Pi) the operation after the first satellite-receiver distance correction (S i j j i 1 = ρ j -cdT + d j trop + d j iono / Li +? j Pi)
Receiver correction distance (Si j 2) = ρi j + cdt after receiving the delay distance cdt j and the inter-system bias ISB j due to the receiver time clock error dtj derived by the positioning information estimation j + ISB j -cdT j + d j trop + d j iono / Li + ε j Pi) a global positioning system integrated with the multi-satellite positioning system configured to derive by calculation.
Where j is the GNSS satellite identifier, i is the ith frequency, ρi j is the geometry range between the satellite and receiver, dt j is the receiver clock error, dT j is the satellite clock error, ISBj (Intersystem biases) The system bias, c is the velocity of light, d j trop convective layer delay error, d j iono / Li is the ionospheric delay error of the GNSS satellite with the ith frequency, and ε j Pi is the receiver noise and multipath error.
The method of claim 2,
The ionospheric delay error ( dj iono / Li ) of the GNSS satellite having the i-
Global Positioning System using a multi - satellite navigation system calculated by Klob (f GPSLi / f GLSSL i) 2 * Klob.
Where f GPSLi is the GPS Li frequency, f GLSSLi is the GPS Li, GLonASS Li, Bi of BeiDou Bi, and Li frequency of QZSS, Klob is the ionospheric delay value calculated through the Klobuchar model.
The apparatus according to claim 1,
A global positioning device using a multiple satellite navigation system configured to derive a first residual (P i j - S i j 1) and a second residual (P i j - S i j 2).
The apparatus of claim 1, wherein the time and coordinate transformer comprises:
Wherein the global satellite positioning system is configured to convert a time system and a coordinate system of a received satellite signal of the multi-satellite navigation system into a reference time system and a reference coordinate system of a reference satellite navigation system.
The positioning system according to claim 1,
And estimating positioning information including at least one of position information, a clock error, and a system-to-system bias by applying a weighted least squares method.
The method according to claim 6, wherein the positioning information (
Figure 112015089536089-pat00024
),
Figure 112015089536089-pat00025

Figure 112015089536089-pat00026
,
Figure 112015089536089-pat00027
,
Figure 112015089536089-pat00028
,
Global Positioning System Using Multi - satellite Navigation System Estimated by.
H is a design matrix, W is a weighted matrix according to a satellite elevation angle,
Figure 112015089536089-pat00029
G is GPS, R is GLONASS, C is BeiDou, Q is QZSS, and E is elevation angle.
The residual extraction unit derives the satellite-receiver distance (P i j , j is the GNSS satellite identifier, i is the i-th frequency) using the time information of the satellite signal output from the receiver, corrects the receiver- (P i j -S i j ( j )) which is a difference between the first satellite-receiver correction distance (S i j 1 = ρ i j -cdT j + d j trop + d j iono / Li + 1) is extracted;
A time and coordinate transformation process of converting the time coordinate system and the coordinate system of the received satellite signal of the multi-satellite navigation system into the reference time coordinate system and the reference coordinate system of the reference satellite navigation system;
A first positioning information estimation process of estimating first positioning information including at least one of position information, a clock error, and a system-to-system bias by applying a weighted least squares method to the first residual;
The residual extraction unit receives the delay distance cdt j and the inter-system bias ISB j due to the receiver time clock error dt j derived from the first positioning information and outputs the second satellite-receiver correction distance S i j 2 ) = ρ i j + cdt j + ISB j -cdT j + d j trop + d j iono / Li + ε j Pi) and calculating the second residual (P i j - S i j 2) A second residual extraction process for deriving the second residual; And
The positioning information estimating unit estimates second positioning information including at least one of position information, a clock error, and a system-to-system bias by applying a weighted least squares method to the second residual and outputs the second positioning information as positioning information including the position of the receiving unit 2 positioning information estimation process using the multi-satellite navigation system.
Where j is the GNSS satellite identifier, ρ i j is the geometry range between the satellite and receiver, dt j is the receiver clock error, dT j is the satellite clock error, ISB j is the inter-system bias, c is the speed of light, d j trop convection zone) delay error, d j iono / Li is i ionospheric delay error of the GNSS satellite having a first frequency, ε j Pi is the receiver noise and multipath error.
The method of claim 8,
Wherein the second positioning information estimation process is repeatedly performed after the second positioning information estimation process is performed until the positioning information satisfies a preset accuracy, Integrated positioning method.
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