KR20230091608A - Apparatus and method for determining a navigation error in a global navigation satellite system - Google Patents

Abstract

This disclosure relates to a method for determining navigation errors in a satellite navigation system. According to this disclosure, a method of operating a navigation error determination device includes the steps of: obtaining a first pseudorange measurement between a first satellite and a first receiver; obtaining a second pseudorange measurement between the first satellite and a second receiver; determining a first differential adjustment value based on a difference between the first and second pseudorange measurements; and determining navigation errors, based on the first differential adjustment value.

Description

Apparatus and method for determining a navigation error in a satellite navigation system

The present disclosure relates generally to satellite navigation systems, and more particularly to an apparatus and method for determining a navigation error in a satellite navigation system.

A satellite system refers to a system that uses a ground station and satellites to perform missions using satellites, and a global navigation satellite system (GNSS) is a type of satellite system, in which a number of navigation satellites deployed in outer space transmit It directs the radionavigation system that can calculate its position and time by receiving the signal from the ground receiver or aircraft. In a satellite navigation system, a receiver may receive a signal from a navigation satellite, calculate a distance between the satellite and the receiver, and determine a position and time of the receiver using the calculation result.

Since the navigation satellites in the satellite navigation system are located in outer space, a number of error factors exist in the propagation process of radio waves from the satellite to the receiver. That is, various error factors such as measurement errors generated by receivers, measurement errors generated by satellites, ionospheric errors, tropospheric errors, multi-path errors, and noise errors may occur during the satellite navigation calculation process. According to one example, the ionosphere is a major cause of satellite signal delay, and it is difficult for a receiver to accurately receive a signal due to a propagation delay related to a residual error in the ionosphere. Free electrons in the ionosphere are mainly generated by ionization of neutral atoms or molecules by ultraviolet rays emitted by the sun. Accordingly, active ionization generally increases the density of free electrons during the day and increases the amount of propagation delay. Propagation delay is reduced.

Conventionally, in order to improve the accuracy of satellite navigation determination, a navigation error determination device for estimating and correcting an error generated in a process of propagating radio waves from a navigation satellite to a receiver has been used. However, the conventional navigation error determination device is greatly affected by the surrounding radio wave environment, and has a problem in that correction performance varies greatly depending on the surrounding environment. In response to this, there has recently been a demand for technology development related to a method for accurately calculating satellite navigation errors.

The foregoing technology is technical information that the inventor possessed for derivation of the present invention or acquired during the derivation process of the present invention, and does not necessarily indicate a known technology disclosed to the general public prior to filing the present invention.

Based on the above discussion, the present disclosure provides an apparatus and method for determining a navigation error in a satellite navigation system.

In addition, the present disclosure provides an apparatus and method for removing a common error component of receivers by determining a navigation error using a plurality of receivers in a satellite navigation system.

In addition, the present disclosure provides an apparatus and method for reducing an ionospheric error and an error due to an unknown number by determining a navigation error using a plurality of receivers in a satellite navigation system.

In addition, the present disclosure provides an apparatus and method for monitoring a change in radio wave environment around a reference station on the ground by determining a navigation error using a plurality of receivers in a satellite navigation system.

According to various embodiments of the present disclosure, in a satellite navigation system, a method of operating a navigation error determination device includes obtaining a first pseudorange measurement value between a first satellite and a first receiver, and between the first satellite and a second receiver. obtaining a second pseudorange measurement of , determining a first differential adjustment value based on a difference between the first pseudorange measurement and the second pseudorange measurement, and based on the first differential adjustment value, It may include determining a navigation error.

According to another embodiment, the first difference adjustment value is composed of a sum of a plurality of difference values, and the plurality of difference values are a distance from the first receiver to broadcasting coordinates of the first satellite and the second receiver. A difference value of a distance from the broadcasting coordinates of the first satellite, a difference value between a time error of the first receiver and a time error of the second receiver, included in a pseudorange measurement value from the first receiver to the first satellite The difference between the multipath error and the multipath error included in the pseudorange measurement from the second receiver to the first satellite, and the receiver noise error included in the pseudorange measurement from the first receiver to the first satellite and the and a differential value of receiver noise error included in the pseudorange measurement value from the second receiver to the first satellite.

According to another embodiment, a distance from the first receiver to broadcasting coordinates of the first satellite may be the same as a distance from the second receiver to broadcasting coordinates of the first satellite.

According to another embodiment, the time error of the first receiver and the time error of the second receiver may be the same.

According to another embodiment, the first differential adjustment value may be determined based on the following equation.

(mathematical expression)

Here, i is the first receiver, k is the second receiver, j is the first satellite, ρ _i ^j is the first pseudorange measurement value, ρ _k ^j is the second pseudorange measurement value, d _i ^j , d _k ^j is the distance between broadcast coordinates from i to j, the distance between broadcast coordinates from k to j, and δR _i ^j and δR _k ^j are the position errors of broadcast coordinates of j included in the pseudodistance measurements from i to j, respectively. , the broadcast coordinate position error of j included in the pseudo distance measurement from k to j, B _i , B _k are the visual error of i, the visual error of k, I _i ^j , T _i ^j , M _i ^j , E _i ^j is the ionospheric error, tropospheric error, multipath error, noise error of i included in the pseudorange measurements from i to j, respectively, and I _k ^j , T _k ^j , M _k ^j , E _k ^j are respectively from k to j It can indicate the ionospheric error, tropospheric error, multi-path error, and noise error of k included in the pseudorange measurements to .

According to another embodiment, the determining of the navigation error includes obtaining a third pseudorange measurement between a second satellite and the first receiver, and a fourth pseudorange measurement between the second satellite and the second receiver. Obtaining a difference between the third pseudorange measurement and the fourth pseudorange measurement, determining a second differential adjustment value, and a difference between the first differential adjustment value and the second differential adjustment value. Based on , determining the navigation error may be included.

According to another embodiment, a method of operating a navigation error determination apparatus includes determining differential adjustment values based on a preset time interval, identifying whether a variation amount of the differential adjustment values is greater than or equal to a threshold value, and When the amount of change is equal to or greater than the threshold value, the method may further include providing a signal indicating a change in the propagation environment to the user.

According to various embodiments of the present disclosure, in a satellite navigation system, an apparatus for determining a navigation error includes a control unit, wherein the control unit acquires a first pseudorange measurement value between a first satellite and a first receiver, and obtain a second pseudorange measurement between a second receiver, determine a first differential adjustment value based on a difference between the first pseudorange measurement and the second pseudorange measurement, and based on the first differential adjustment value , the navigation error can be determined.

According to another embodiment, the distance from the first receiver to the broadcasting coordinates of the first satellite is the same as the distance from the second receiver to the broadcasting coordinates of the first satellite, and the time error of the first receiver The second receiver may have the same visual error.

According to another embodiment, the control unit obtains a third pseudorange measurement between a second satellite and the first receiver, obtains a fourth pseudorange measurement between the second satellite and the second receiver, and 3 A second differential adjustment value may be determined based on a difference between the pseudorange measurement value and the fourth pseudorange measurement value, and a navigation error may be determined based on the difference between the first differential adjustment value and the second differential adjustment value. there is.

Each of the various aspects and features of the invention are defined in the appended claims. Combinations of features of the dependent claims may be combined with features of the independent claims as appropriate, not just those explicitly set forth in the claims.

In addition, one or more selected features of any one embodiment described in this disclosure may be combined with one or more selected features of any other embodiment described in this disclosure, and alternatives of such features The combination of the present disclosure at least partially alleviates one or more technical problems discussed in the present disclosure, or at least partially alleviates the technical problems discernable by a person skilled in the art from the present disclosure, and further features of the embodiments ( A particular combination or permutation so formed of embodiment features is possible, provided that it is not understood by a person skilled in the art to be incompatible.

In any described example implementation, two or more physically separate components may alternatively be integrated into a single component, where such integration is possible, and a single component so formed If the same function is performed by , the integration is possible. Conversely, a single component in any embodiment described in this disclosure may alternatively be implemented as two or more separate components that achieve the same function, where appropriate.

It is an object of certain embodiments of the present invention to address, mitigate, or eliminate, at least in part, at least one of the problems and/or disadvantages associated with the prior art. Certain embodiments aim to provide at least one of the advantages described below.

An apparatus and method according to various embodiments of the present disclosure enable a satellite navigation error to be accurately determined in a satellite navigation system.

Also, an apparatus and method according to various embodiments of the present disclosure enable a navigation error to be determined using a plurality of receivers in a satellite navigation system, thereby removing a common error component of the receivers.

In addition, the apparatus and method according to various embodiments of the present disclosure can reduce ionospheric errors and errors due to unspecified integers by determining navigation errors using a plurality of receivers in a satellite navigation system.

In addition, the apparatus and method according to various embodiments of the present disclosure enable a navigation error to be determined using a plurality of receivers in a satellite navigation system, thereby monitoring a change in the radio wave environment around a reference station on the ground.

In addition, the apparatus and method according to various embodiments of the present disclosure can reduce the maintenance cost of the satellite navigation system by monitoring a change in the radio wave environment around the reference station in the satellite navigation system.

Effects obtainable in the present disclosure are not limited to the effects mentioned above, and other effects not mentioned may be clearly understood by those skilled in the art from the description below. will be.

1 illustrates a satellite navigation system according to various embodiments of the present disclosure.
2 illustrates a schematic diagram of a signal transmission process for determining a navigation error in a satellite navigation system according to various embodiments of the present disclosure.
3 illustrates a configuration of a navigation error determining device 360 in a satellite navigation system according to various embodiments of the present disclosure.
4 is a schematic diagram of a method for determining a navigation error in a satellite navigation system according to various embodiments of the present disclosure.
FIG. 5 is a flowchart illustrating a method for determining a navigation error by a navigation error determination device using a single satellite in a satellite navigation system according to various embodiments of the present disclosure.
6 is a flowchart illustrating a method for determining a navigation error by using a plurality of satellites by a navigation error determining apparatus in a satellite navigation system according to various embodiments of the present disclosure.

Terms used in the present disclosure are only used to describe a specific embodiment, and may not be intended to limit the scope of other embodiments. Singular expressions may include plural expressions unless the context clearly dictates otherwise. Terms used herein, including technical or scientific terms, may have the same meaning as commonly understood by one of ordinary skill in the art described in this disclosure. Among the terms used in the present disclosure, terms defined in general dictionaries may be interpreted as having the same or similar meanings as those in the context of the related art, and unless explicitly defined in the present disclosure, ideal or excessively formal meanings. not be interpreted as In some cases, even terms defined in the present disclosure cannot be interpreted to exclude embodiments of the present disclosure.

In various embodiments of the present disclosure described below, a hardware access method is described as an example. However, since various embodiments of the present disclosure include technology using both hardware and software, various embodiments of the present disclosure do not exclude software-based access methods.

Hereinafter, the present disclosure relates to an apparatus and method for determining a navigation error in a satellite navigation system. Specifically, this disclosure describes techniques for reducing navigation errors in a satellite navigation system.

Hereinafter, various embodiments will be described in detail so that those skilled in the art can easily implement the present disclosure with reference to the accompanying drawings. However, since the technical spirit of the present disclosure may be implemented in various forms, it is not limited to the embodiments described herein. In describing the embodiments disclosed in this specification, if it is determined that a detailed description of a related known technology may obscure the gist of the technical idea of the present disclosure, a detailed description of the known technology will be omitted. The same or similar components are assigned the same reference numerals, and duplicate descriptions thereof will be omitted.

In this specification, when an element is described as being “connected” to another element, this includes not only the case of being “directly connected” but also the case of being “indirectly connected” with another element intervening therebetween. When an element "includes" another element, this means that it may further include another element without excluding another element in addition to the other element unless otherwise stated.

Some embodiments may be described as functional block structures and various processing steps. Some or all of these functional blocks may be implemented with any number of hardware and/or software components that perform a particular function. For example, the functional blocks of the present disclosure may be implemented by one or more microprocessors or circuit configurations for a predetermined function. The functional blocks of this disclosure may be implemented in a variety of programming or scripting languages. The functional blocks of this disclosure may be implemented as an algorithm running on one or more processors. The functions performed by the function blocks of the present disclosure may be performed by a plurality of function blocks, or the functions performed by the plurality of function blocks in the present disclosure may be performed by one function block. In addition, the present disclosure may employ prior art for electronic environment setting, signal processing, and/or data processing.

In addition, in the present disclosure, the expression of more than or less than is used to determine whether a specific condition is satisfied or fulfilled, but this is only a description to express an example and excludes more or less description. It's not about doing it. Conditions described as 'above' may be replaced with 'exceeds', conditions described as 'below' may be replaced with 'below', and conditions described as 'above and below' may be replaced with 'above and below'.

1 illustrates a satellite navigation system 100 according to various embodiments of the present disclosure.

The satellite navigation system 100 indicates a system for delivering GNSS error correction information and integrity information applicable to GNSS users located on the ground or in the air using an artificial satellite network. According to the satellite navigation system 100, a satellite may receive a signal from a communicator on the ground and transmit a signal to a receiver or a mobile body. Referring to FIG. 1 , a satellite navigation system 100 may include a satellite 101, a central processing station 103, a reference station 105, a communication station 107, and a mobile body 109.

The satellite 101 indicates a device that orbits around the earth and performs a satellite mission. According to an embodiment of the present disclosure, in order to perform a satellite mission, the satellite 101 may collect information related to the satellite mission, and transmit the collected information to the ground or mobile body 109 using a transponder transceiver. there is. According to an embodiment of the present disclosure, the satellite 101 may transmit information about correction of the receiver position to the receiver. The satellite 101 is a celestial body orbiting around the earth, and regions such as the ionosphere and the convection layer exist between the satellite and the earth. In the satellite navigation system 100, the ionosphere and the convection layer are one of the elements that cause delay errors in the signal propagation process. signal can be received.

The central processing station 103 instructs a ground station to process signals received from satellites. The central processing station 103 may perform a function of integrally managing signals transmitted from satellites. The central processing station 103 may receive signal data received from satellites by receivers on the ground and process the data. In addition, the central processing station 103 may generate a signal to be transmitted to the satellite 101 and transmit it to the communication station 107.

The reference station 105 instructs the ground station to receive a signal from the satellite 101 . The reference station 105 may collect signals transmitted from satellites. According to an embodiment of the present disclosure, the reference station 105 may include at least one receiver installed on the ground to receive a signal from a satellite. At least one receiver may be configured with an antenna for receiving a signal from a satellite, and may collect signals using the antenna. The reference station 105 may forward the collected signals to the central processing station 103 .

The communication station 107 performs a function of transmitting signals to the satellite 101. The communication station 107 may transmit a signal including error correction information and integrity information to the satellite 101 for terrestrial broadcasting.

According to the satellite navigation system 100, the reference station 105 may include at least one receiver, and may perform a data processing procedure for estimating and correcting errors generated in the process of propagating navigation satellites and radio waves. To perform this data processing procedure, a navigation error determining device may be used. The navigation error determining device indicates a device for determining an error generated in a process of propagating radio waves in the satellite navigation system 100 . According to an embodiment of the present disclosure, the navigation error determination device may indicate a separate external device connected to the central processing station 103 or the reference station 105. According to another embodiment of the present disclosure, the navigation error determination device may be installed and operated in a computing device of the central processing station 103 or a computing device of the reference station 105 .

The navigation error determination device measures a pseudorange about the distance between the satellite 101 and the receiver of the reference station 105, and extracts a navigation error component included in the pseudorange. Pseudorange measurement is greatly affected by obstacles and radio interference, and as multipath error components and noise components are reflected in the pseudorange measurement value, the error correction performance of the navigation error determination device may deteriorate when the radio environment changes.

According to the prior art, the navigation error determination device calculates a code minus carrier (CMC) value using a pseudorange measurement value and a carrier measurement value among data measured by a receiver of the reference station 105, and continuously checks the influence of the radio wave environment to determine the radio environment effect. Changes were recognized. Specifically, the pseudorange measurement value measured by the receiver of the reference station 105 may be determined based on Equation 1.

Referring to Equation 1, i is a receiver, j is a satellite, ρ _i ^j is a pseudo distance measurement from i to j, d _i ^j is the distance from i to the broadcast coordinate of j, and δR _i ^j is from i The broadcast coordinate position error of j included in the pseudorange measurement to j, b ^j is the visual error of j, B _i is the visual error of i, I _i ^j , T _i ^j , M _i ^j , E _i ^j are respectively i Indicates the ionospheric error, tropospheric error, multipath error, and noise error of i included in the pseudorange measurements from j to j.

Also, the carrier measurement value measured by the receiver of the reference station 105 may be determined based on Equation 2.

Referring to Equation 2, i is a receiver, j is a satellite, φ _i ^j is the carrier measurement value from i to j, d _i ^j is the distance between the broadcast coordinates from i to j, and δR _i ^j is from i to j j's broadcast coordinate position error included in the pseudodistance measurement to j, b ^j is the visual error of j, B _i is the visual error of i, I _i ^j and T _i ^j are included in the pseudo distance measurement from i to j, respectively. ionospheric error, convective error, λ is the wavelength of the carrier wave, N _i ^j , m _i ^j , ε _i ^j are unknown integers included in the measured values of the carrier waves from i to j, respectively, multipath error, noise error of i instruct

That is, the navigation error determination device can determine the difference between the pseudorange carriers using the pseudorange measurement value determined based on <Equation 1> and the carrier measurement value determined based on <Equation 2>. A difference value between pseudorange carriers may be determined based on Equation 3.

Referring to <Equation 3>, i is a receiver, j is a satellite, ρ _i ^j , φ _i ^j are a pseudorange measurement value from i to j, a carrier measurement value, and I _i ^j are a pseudorange measurement value from i to j, respectively. ionospheric error included in , λ is the wavelength length of the carrier, N _i ^j , m _i ^j , ε _i ^j are unknown integers included in the measured values of carriers from i to j, respectively, multipath error, i receiver noise error, M _i ^j _, E _i ^j denote the multipath error included in the pseudorange measurement value from i to j, and the noise error of i.

According to the navigation error determined as in Equation 3, an ionospheric error component and an unspecified carrier component were included in the CMC measurement value, so it was not possible to accurately confirm a change in the propagation environment. Correspondingly, the navigation error determination device can correct the error by applying a leveling technique, but if a cycle slip occurs in the measured value of the carrier or the ionospheric error is large at a low elevation angle, only the desired radio wave environment component is extracted and the radio environment is monitored. I had a difficult problem.

FIG. 2 illustrates a schematic diagram 200 of a signal transmission process for determining a navigation error in the satellite navigation system 100 according to various embodiments of the present disclosure. Referring to FIG. 2 , the satellite navigation system 100 may include at least one satellite and a reference station including a plurality of receivers. FIG. 2 illustrates a case in which two satellites 201 and 203 and two receivers 211 and 213 are configured in the satellite navigation system 100, but the number of satellites and receivers may change depending on the deployment situation. .

In the satellite navigation system 100, the reference station 105 may include a plurality of receivers in order to prepare for a failure of equipment such as a receiver. The receiver may point to an antenna receiving a signal from a satellite. According to an embodiment of the present disclosure, a plurality of receivers may be arranged to be 120 m apart. Here, the navigation error determination apparatus may determine the navigation error using pseudorange measurement values measured between at least one satellite and a plurality of receivers. The navigation error determination apparatus can monitor the environment using only propagation environment components such as multipath and noise by differentiating pseudorange measurements measured using a plurality of receivers and removing a common error component.

According to an embodiment of the present disclosure, the first receiver 211 and the second receiver 213 may receive signals from at least one of the first satellites 201 and 203 . Here, the first receiver 211 and the second receiver 213 may measure a pseudorange between at least one of the first to second satellites 201 and 203 .

The navigation error determination device may determine the navigation error using a single satellite. According to an embodiment of the present disclosure, the first receiver 211 may measure a first pseudorange using a signal received from the first satellite 201, and the second receiver 213 may measure the first pseudorange ( The second pseudorange may be measured using the signal received from 201). The first receiver 211 and the second receiver 213 may transmit the measured first pseudorange and the second pseudorange to the manager 231 .

The navigation error determination apparatus may determine the navigation error using multiple satellites. According to an embodiment of the present disclosure, along with determining the first pseudorange measurement value and the second pseudorange measurement value, the first receiver 211 determines the third pseudorange by using the signal received from the second satellite 203. measurement, and the second receiver 213 can measure the fourth pseudorange using the signal received from the second satellite 203 . The first receiver 211 and the second receiver 213 may transmit the measured third pseudorange and fourth pseudorange to the manager 231 .

The manager 231 may instruct a device for monitoring the state of the reference station 105 and a radio wave environment around the reference station. According to an embodiment of the present disclosure, when the navigation error determination device is installed inside the manager 231, a difference adjustment value may be determined using a difference between the first pseudorange and the second pseudorange, and the difference adjustment value The navigation error can be determined from According to another embodiment of the present disclosure, when the navigation error determining device is connected to the outside of the manager 231, the manager 231 may transmit information about the first pseudorange and the second pseudorange to the navigation error determining device. there is. Thereafter, the navigation error determination device may determine a difference adjustment value using the received information. According to an embodiment of the present disclosure, the differential adjustment value may indicate an error value including a component related to a propagation environment, such as a multipath error or a receiver noise error. The navigation error determination device may determine and correct the navigation error from the differential adjustment value. The specific configuration and operating method of the navigation error determination device will be described in detail with reference to FIGS. 3 to 6 .

3 illustrates a configuration 300 of a navigation error determination device 360 in the satellite navigation system 100 according to various embodiments of the present disclosure. '...' is used below. wealth', '… A term such as 'group' refers to a unit that processes at least one function or operation, and may be implemented as hardware, software, or a combination of hardware and software. The navigation error determination device 360 may include a communication unit 310 , a storage unit 320 , and a control unit 330 .

The communication unit 310 performs functions for transmitting and receiving signals through a wireless or wired channel. All or part of the communication unit 310 may be referred to as a transmission unit, a reception unit, or a transmission and reception unit. According to an embodiment of the present disclosure, the communication unit 310 may receive a first pseudorange measurement value and a second pseudorange measurement value. Also, the communication unit 301 may additionally receive a third pseudorange measurement value and a fourth pseudorange measurement value together with the first pseudorange measurement value and the second pseudorange measurement value.

The storage unit 320 stores data such as a basic program for operation of the navigation error determination device 360, an application program, and setting information. The storage unit 320 may include volatile memory, non-volatile memory, or a combination of volatile and non-volatile memories. Also, the storage unit 320 may provide stored data according to the request of the control unit 330 .

The controller 330 controls overall operations of the navigation error determination device 360 . For example, the control unit 330 may transmit and receive signals through the communication unit 310 . Also, the control unit 330 may record data in the storage unit 320 . According to various embodiments of the present disclosure, the control unit 330 controls to acquire information on a pseudorange measurement value between a satellite and a receiver, performs an operation for determining a difference adjustment value based on a difference between the pseudorange measurements, and , an operation for determining a navigation error based on the differential adjustment value may be performed. For example, the controller 330 may control the navigation error determination device 360 to perform operations according to various embodiments described later.

4 illustrates a schematic diagram 400 of a method for determining a navigation error in the satellite navigation system 100 according to various embodiments of the present disclosure. Referring to FIG. 4 , the satellite navigation system 100 includes a first satellite 201, a second satellite 203, a first receiver 211, a second receiver 213, a manager 231, and navigation error determination. Device 360 may be included.

Referring to FIG. 4 , the navigation error determination device 360 may determine a navigation error based on pseudorange measurement values using a plurality of receivers. According to an embodiment of the present disclosure, the navigation error determination apparatus 360 may determine a first differential adjustment value by calculating a difference between pseudorange measurement values for one satellite and each of a plurality of receivers. Thereafter, the navigation error determination device 360 may determine a navigation error based on the first differential adjustment value. Here, when the plurality of receivers are not synchronized, the navigation error determination device 360 may additionally obtain information about pseudorange measurement values for each of the plurality of satellites and the plurality of receivers. The navigation error determining unit 360 may determine a second difference adjustment value by calculating a difference between the additionally obtained pseudorange measurement values. Thereafter, the navigation error determination apparatus 360 may calculate a difference between the first differential adjustment value and the second differential adjustment value to finally determine the navigation error.

Each of the first receiver 211 and the second receiver 213 determines a pseudorange measurement value using the received signals. The first pseudorange measurement value ρ _i ^j determined by the first receiver 211 and the pseudorange measurement value ρ _k ^j determined by the second receiver may be determined based on Equation 4.

Referring to Equation 4, i is the first receiver, k is the second receiver, j is a satellite, ρ _i ^j , ρ _k ^j are pseudo distance measurements from i to j, and pseudo distances from k to j, respectively. The measurements, d _i ^j , d _k ^j , the distance from i to the broadcast coordinate of j, and the distance from k to the broadcast coordinate of j, δR _i ^j , δR _i ^{j ,} respectively, are the values of j included in the pseudodistance measurement from i to j. broadcast coordinate position error, the broadcast coordinate position error of j included in the pseudo distance measurement from k to j, b ^j is the visual error of j, B _i , B _k are the visual error of i, the visual error of k, I _i ^j , T _i ^j , M _i ^j , E _i ^j are the ionospheric error, tropospheric error, multipath error, noise error of i, I _k ^j , T _k ^j , included in the pseudorange measurements from i to j, respectively. M _k ^j , E _k ^j indicate the ionospheric error, tropospheric error, multipath error, and noise error of k included in the pseudorange measurements from k to j, respectively.

The navigation error determination device 360 may determine a first difference adjustment value based on a difference between the first pseudorange measurement value ρ _i ^j and the second pseudorange measurement value ρ _k ^j . The first difference adjustment value ρ _i ^j -ρ _k ^j may be determined based on Equation 5.

Referring to Equation 5, i is the first receiver, k is the second receiver, j is the first satellite, ρ _i ^j , ρ _k ^j are pseudo distance measurements from i to j, and from k to j The pseudorange measurements, d _i ^j and d _k ^j , are the distance between the broadcast coordinates from i to j, and the distance between the broadcast coordinates from k to j, δR _i ^j and δR _k ^j are the pseudo distance measurements from i to j, respectively The broadcast coordinate position error of j included in , the broadcast coordinate position error of j included in the pseudo distance measurement value from k to j, B _i , B _k are the visual error of i, the visual error of k, I _i ^j , T _i ^j , M _i ^j , E _i ^j are the ionospheric error, tropospheric error, multipath error, noise error of i, I _k ^j , T _k ^j , and M _k ^j included in the pseudorange measurements from i to j, respectively. , E _k ^j indicate the ionospheric error, tropospheric error, multipath error, and noise error of k included in the pseudorange measurements from k to j, respectively.

At this time, since the precise positions of the first receiver 211 and the second receiver 213 can be obtained through surveying, d _i ^j -d _k ^j uses the precise position of the antenna of the receiver and the satellite position calculated from the navigation data. so it can be removed. That is, when the distance from the first receiver 211 to the broadcasting coordinates of the first satellite 201 and the distance from the second receiver 213 to the broadcasting coordinates of the first satellite 201 are the same, the first differential adjustment value ρ _i ^j -ρ _k ^j may be determined based on Equation 6.

는 i로부터 j까지의 의사 거리 측정치와 k로부터 j까지의 의사 거리 측정치의 차분 조정 값, B_i, B_k는 각각 i의 시각 오차, k의 시각 오차, M_i ^j, E_i ^j는 각각 i로부터 j까지의 의사 거리 측정치에 포함된 다중 경로 오차, i의 잡음 오차, M_k ^j, E_k ^j는 각각 k로부터 j까지의 의사 거리 측정치에 포함된 다중 경로 오차, k의 잡음 오차를 지시한다.Referring to Equation 6, i is the first receiver, k is the second receiver, j is the first satellite,

is the difference adjustment value between the pseudo distance measurement from i to j and the pseudo distance measurement from k to j, B _i , B _k are the visual error of i, the visual error of k, M _i ^j and E _i ^j are respectively i The multipath error included in the pseudodistance measurement from k to j, the noise error of i, M _k ^j , and E _k ^j indicate the multipath error included in the pseudorange measurement from k to j and the noise error of k, respectively. .

At this time, when the first receiver 211 and the second receiver 213 are synchronized according to the same reference time, the difference between the time error of the first receiver and the time error of the second receiver becomes zero. That is, when the time error of the first receiver and the time error of the second receiver are the same, the first difference adjustment value ρ _i ^j -ρ _k ^j may be determined based on Equation 7.

는 i로부터 j까지의 의사 거리 측정치와 k로부터 j까지의 의사 거리 측정치의 차분 조정 값, M_i ^j, E_i ^j는 각각 i로부터 j까지의 의사 거리 측정치에 포함된 다중 경로 오차, i의 잡음 오차, M_k ^j, E_k ^j는 각각 k로부터 j까지의 의사 거리 측정치에 포함된 다중 경로 오차, k의 잡음 오차를 지시한다.Referring to Equation 7, i is the first receiver, k is the second receiver, j is the first satellite,

is the difference adjustment value between the pseudorange measurements from i to j and the pseudorange measurements from k to j, M _i ^j , E _i ^j are the multipath errors included in the pseudorange measurements from i to j, respectively, and the noise of i The errors, M _k ^j and E _k ^j , indicate the noise error of k, a multipath error included in the pseudorange measurements from k to j, respectively.

As a result, when the two receivers are synchronized according to the same reference time, the first differential adjustment value may be composed of information about the multipath error M and the receiver noise error E. The navigation error determination device 360 may monitor a radio wave environment around the receiver by estimating an error using the determined first differential adjustment value.

However, when the first receiver 211 and the second receiver 213 are not synchronized according to the same reference time, an additional procedure for removing a time error of the receivers may be performed. The navigation error determining unit 360 may remove the time error using pseudo distance measurements between the first receiver 211, the second receiver 213, and the second satellite 203. That is, the navigation error determining unit 360 calculates the third pseudorange measurement value ρ _i ^p between the first receiver 211 and the second satellite 203 and the second pseudo distance between the second receiver 213 and the second satellite 203. 4 A second difference adjustment value ρ _{i p} ^-ρ _k ^p , which is a difference value between pseudorange measurement values ρ k ^p , may be determined. Thereafter, the navigation error determination device 360 may determine the navigation error through a difference operation between the first differential adjustment value ρ _i ^j -ρ _k ^j and the second differential adjustment value ρ _i ^p -ρ _k ^p . A difference between the first differential adjustment value and the second differential adjustment value may be determined based on Equation 8.

는 제1 차분 조정 값과 제2 차분 조정 값의 차이, M_i ^j, E_i ^j는 각각 i로부터 j까지의 의사 거리 측정치에 포함된 다중 경로 오차, i의 잡음 오차, M_k ^j, E_k ^j는 각각 k로부터 j까지의 의사 거리 측정치에 포함된 다중 경로 오차, k의 잡음 오차, M_i ^p, E_i ^p는 각각 i로부터 p까지의 의사 거리 측정치에 포함된 다중 경로 오차, i의 잡음 오차, M_k ^p, E_k ^p는 각각 k로부터 p까지의 의사 거리 측정치에 포함된 다중 경로 오차, p의 잡음 오차를 지시한다.Referring to Equation 8, i is the first receiver, k is the second receiver, j is the first satellite, p is the second satellite,

are the difference between the first difference adjustment value and the second difference adjustment value, M _i ^j , E _i ^j are the multipath error included in the pseudorange measurement from i to j, the noise error of i, M _k ^j , E _{k ,} respectively ^j is the multipath error included in the pseudorange measurements from k to j, the noise error of k, M _i ^p , E _i ^p are the multipath errors included in the pseudorange measurements from i to p, respectively, and the noise of i The errors, M _k ^p and E _k ^{p ,} indicate the noise error of p, a multipath error included in the pseudorange measurements from k to p, respectively.

As a result, when the two receivers are not synchronized according to the same reference time, the difference between the differential adjustment values may be composed of information about the multipath error M and the receiver noise error E. The navigation error determination device 360 may monitor the propagation environment around the receiver by estimating the error using the difference between the determined differential adjustment values. Additionally, the navigation error determination device 360 may calculate and store differential adjustment values according to a preset time interval, and detect a change in the environment of the satellite navigation system 100 using a change in the differential adjustment values. The navigation error determination device 360 may collect and store differential adjustment values every second, monitor changes in the radio wave environment around the reference station by checking changes in the differential adjustment values while the satellite navigation system 100 is operating, and generate an anomaly. follow-up can be performed.

According to an embodiment of the present disclosure, the navigation error determination apparatus 360 determines a plurality of navigation errors based on a preset time interval, identifies whether a variation amount of the plurality of navigation errors is greater than or equal to a threshold value, and When the amount is greater than or equal to the threshold value, a signal indicating a change in the propagation environment may be provided to the user.

FIG. 5 is a flowchart 500 illustrating a method for determining a navigation error by using a single satellite by the navigation error determination device 360 in the satellite navigation system 100 according to various embodiments of the present disclosure. 5 illustrates a method of determining a navigation error using the first satellite 201, the first receiver 211, and the second receiver 213.

Referring to FIG. 5 , in step 501, the navigation error determination device 360 obtains a first pseudorange measurement between the first satellite and the first receiver. According to an embodiment of the present disclosure, the navigation error determination device 360 may obtain a first pseudorange measurement value regarding a pseudorange from the first satellite 201 to the first receiver 211 .

In step 503, the navigation error determination device 360 obtains a second pseudorange measurement between the first satellite and the second receiver. According to an embodiment of the present disclosure, the navigation error determination device 360 may obtain a second pseudorange measurement value regarding a pseudorange from the first satellite 201 to the second receiver 213 .

In step 505, the navigation error determination device 360 determines a first differential adjustment value based on a difference between the first pseudorange measurement value and the second pseudorange measurement value. The navigation error determining unit 360 may determine the first difference adjustment value through a difference operation between the first pseudorange measurement value and the second pseudorange measurement value. According to an embodiment of the present disclosure, the first difference adjustment value is composed of a sum of a plurality of difference values, and the plurality of difference values are a distance from the first receiver to broadcasting coordinates of the first satellite and a distance from the second receiver to the broadcasting coordinates of the first satellite. The difference value of the distance to the broadcasting coordinates of the satellite, the difference value between the time error of the first receiver and the time error of the second receiver, the multipath error included in the pseudorange measurement value from the first receiver to the first satellite, and the difference value from the second receiver The difference value of the multipath error included in the pseudorange measurement to the first satellite, and the receiver noise error included in the pseudorange measurement from the first receiver to the first satellite and the pseudorange measurement from the second receiver to the first satellite It may include a differential value of the included receiver noise error.

According to an embodiment of the present disclosure, a distance from the first receiver to broadcasting coordinates of the first satellite may be the same as a distance from the second receiver to broadcasting coordinates of the first satellite. According to an embodiment of the present disclosure, a time error of the first receiver and a time error of the second receiver may be the same.

In step 507, the navigation error determining unit 360 determines a navigation error based on the first differential adjustment value. In the first difference adjustment value, common errors between the first pseudorange measurement value and the second pseudorange measurement value are removed. Accordingly, the navigation error determining unit 360 may estimate and correct the navigation error using the first differential adjustment value.

In addition, the navigation error determination device 360 may monitor the propagation environment using the differential adjustment value. According to an embodiment of the present disclosure, the navigation error determination apparatus 360 determines differential adjustment values based on a preset time interval, identifies whether a change amount of the differential adjustment values is greater than or equal to a threshold value, and determines whether the change amount is a threshold value. If it is greater than or equal to the value, a signal indicating a change in the propagation environment may be provided to the user.

FIG. 6 is a flowchart 600 illustrating a method for determining a navigation error by using a plurality of satellites by the navigation error determination device 360 in the satellite navigation system 100 according to various embodiments of the present disclosure.

6 illustrates a method of determining a navigation error using a first satellite 201, a second satellite 203, a first receiver 211, and a second receiver 213. Also, FIG. 6 illustrates an operation process after the navigation error determination device 360 determines the first differential adjustment value as shown in FIG. 5 .

Referring to FIG. 6 , in step 601, the navigation error determination device 360 obtains a third pseudorange measurement value between the second satellite and the first receiver. According to an embodiment of the present disclosure, the navigation error determination device 360 may obtain a third pseudorange measurement value regarding a pseudorange from the second satellite 203 to the first receiver 211 .

In step 603, the navigation error determination device 360 obtains a fourth pseudorange measurement between the second satellite and the second receiver. According to an embodiment of the present disclosure, the navigation error determination device 360 may obtain a fourth pseudorange measurement value related to a pseudorange from the second satellite 203 to the second receiver 213 .

In step 605, the navigation error determining unit 360 determines a second differential adjustment value based on a difference between the third pseudorange measurement value and the fourth pseudorange measurement value. The navigation error determining unit 360 may determine the second difference adjustment value through a difference operation between the third pseudorange measurement value and the fourth pseudorange measurement value. The second differential adjustment value may be determined in the same way as the method of determining the first differential adjustment value.

In step 607, the navigation error determining unit 360 determines a navigation error based on the difference between the first differential adjustment value and the second differential adjustment value. The navigation error determining unit 360 may determine a difference between the first differential adjustment value and the second differential adjustment value as a final differential adjustment value. Thereafter, common errors of the first pseudorange measurement value to the fourth pseudorange measurement value are removed from the difference value between the first difference adjustment value and the second difference adjustment value. Accordingly, the navigation error determining unit 360 may estimate and correct the navigation error using the difference between the difference adjustment values.

Methods according to the embodiments described in the claims or specification of the present disclosure may be implemented in the form of hardware, software, or a combination of hardware and software.

When implemented in software, a computer readable storage medium storing one or more programs (software modules) may be provided. One or more programs stored in a computer-readable storage medium are configured for execution by one or more processors in an electronic device. The one or more programs include instructions that cause the electronic device to execute methods according to embodiments described in the claims or specification of the present disclosure.

Such programs (software modules, software) may include random access memory, non-volatile memory including flash memory, read only memory (ROM), and electrically erasable programmable ROM. (electrically erasable programmable read only memory (EEPROM), magnetic disc storage device, compact disc-ROM (CD-ROM), digital versatile discs (DVDs), or other It can be stored on optical storage devices, magnetic cassettes. Alternatively, it may be stored in a memory composed of a combination of some or all of these. In addition, each configuration memory may be included in multiple numbers.

In addition, the program is provided through a communication network such as the Internet, an intranet, a local area network (LAN), a wide area network (WAN), or a storage area network (SAN), or a communication network consisting of a combination thereof. It can be stored on an attachable storage device that can be accessed. Such a storage device may be connected to a device performing an embodiment of the present disclosure through an external port. In addition, a separate storage device on a communication network may be connected to a device performing an embodiment of the present disclosure.

In the specific embodiments of the present disclosure described above, components included in the disclosure are expressed in singular or plural numbers according to the specific embodiments presented. However, the singular or plural expressions are selected appropriately for the presented situation for convenience of explanation, and the present disclosure is not limited to singular or plural components, and even components expressed in plural are composed of the singular number or singular. Even the expressed components may be composed of a plurality.

Meanwhile, in the detailed description of the present disclosure, specific embodiments have been described, but various modifications are possible without departing from the scope of the present disclosure. Therefore, the scope of the present disclosure should not be limited to the described embodiments and should not be defined by the scope of the claims described below as well as those equivalent to the scope of these claims.

101 satellite 103 central processing station
105 reference station 107 communication station
109 Mobile
201, 203 1st satellite, 2nd satellite
211, 213 first receiver, second receiver
231 controller 360 navigation error determination device
310 communication unit 320 storage unit
330 control

Claims (11)

A method of operating a navigation error determination device in a satellite navigation system,
obtaining a first pseudorange measurement between a first satellite and a first receiver;
obtaining a second pseudorange measurement between the first satellite and a second receiver;
determining a first differential adjustment value based on a difference between the first pseudorange measurement and the second pseudorange measurement; and
and determining a navigation error based on the first differential adjustment value.
The method of claim 1,
The first difference adjustment value is composed of a sum of a plurality of difference values,
The plurality of difference values,
The difference between the distance from the first receiver to the broadcasting coordinates of the first satellite and the distance from the second receiver to the broadcasting coordinates of the first satellite, the time error of the first receiver and the time error of the second receiver A difference value of a difference value between a multipath error included in the pseudorange measurement value from the first receiver to the first satellite and a multipath error included in the pseudorange measurement value from the second receiver to the first satellite, and the th A navigation error determination device comprising a difference between a receiver noise error included in a pseudorange measurement value from a first receiver to the first satellite and a receiver noise error included in a pseudorange measurement value from the second receiver to the first satellite how it works.
The method of claim 2,
A method of operating a navigation error determination device in which a distance from the first receiver to the broadcasting coordinates of the first satellite is the same as a distance from the second receiver to the broadcasting coordinates of the first satellite.
The method of claim 2,
A method of operating a navigation error determination device in which a time error of the first receiver and a time error of the second receiver are the same.
The method of claim 1,
A method of operating a navigation error determining device in which the first differential adjustment value is determined based on the following equation:

Here, i is the first receiver, k is the second receiver, j is the first satellite, ρ _i ^j is the first pseudorange measurement value, ρ _k ^j is the second pseudorange measurement value, d _i ^j , d _k ^j is the distance between broadcast coordinates from i to j, the distance between broadcast coordinates from k to j, and δR _i ^j and δR _k ^j are the position errors of broadcast coordinates of j included in the pseudodistance measurements from i to j, respectively. , the broadcast coordinate position error of j included in the pseudo distance measurement from k to j, B _i , B _k are the visual error of i, the visual error of k, I _i ^j , T _i ^j , M _i ^j , E _i ^j is the ionospheric error, tropospheric error, multipath error, noise error of i included in the pseudorange measurements from i to j, respectively, and I _k ^j , T _k ^j , M _k ^j , E _k ^j are respectively from k to j Indicates the ionospheric error, tropospheric error, multipath error, and noise error of k included in the pseudorange measurements to .
The method of claim 1,
The step of determining the navigation error,
obtaining a third pseudorange measurement between a second satellite and the first receiver;
obtaining a fourth pseudorange measurement between the second satellite and a second receiver;
determining a second differential adjustment value based on a difference between the third pseudorange measurement and the fourth pseudorange measurement; and
and determining the navigation error based on a difference between the first differential adjustment value and the second differential adjustment value.
The method of claim 1,
determining differential adjustment values based on a preset time interval;
identifying whether a change amount of the difference adjustment values is greater than or equal to a threshold value; and
and providing a user with a signal indicating a change in propagation environment when the amount of change is greater than or equal to a threshold value.
In the satellite navigation system, in the navigation error determination device,
The navigation error determination device includes a control unit,
The control unit,
obtain a first pseudorange measurement between a first satellite and a first receiver;
obtain a second pseudorange measurement between the first satellite and a second receiver;
determine a first differential adjustment value based on a difference between the first pseudorange measurement and the second pseudorange measurement;
A navigation error determination device configured to determine a navigation error based on the first differential adjustment value.
The method of claim 8,
The first difference adjustment value is composed of a sum of a plurality of difference values,
The plurality of difference values,
The difference between the distance from the first receiver to the broadcasting coordinates of the first satellite and the distance from the second receiver to the broadcasting coordinates of the first satellite, the time error of the first receiver and the time error of the second receiver A difference value of a difference value between a multipath error included in the pseudorange measurement value from the first receiver to the first satellite and a multipath error included in the pseudorange measurement value from the second receiver to the first satellite, and Navigation error determination including a difference between a receiver noise error included in the pseudorange measurement from the first receiver to the first satellite and a receiver noise error included in the pseudorange measurement from the second receiver to the first satellite Device.
The method of claim 9,
The distance from the first receiver to the broadcasting coordinates of the first satellite is the same as the distance from the second receiver to the broadcasting coordinates of the first satellite;
The navigation error determination device of claim 1 , wherein a time error of the first receiver and a time error of the second receiver are the same.
The method of claim 8,
The control unit,
obtain a third pseudorange measurement between a second satellite and the first receiver;
obtain a fourth pseudorange measurement between the second satellite and a second receiver;
determine a second differential adjustment value based on a difference between the third pseudorange measurement and the fourth pseudorange measurement;
A navigation error determination device for determining a navigation error based on a difference between the first differential adjustment value and the second differential adjustment value.

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