Position measuring device and position measuring method

Abstract

The present invention provides a position measurement device and a position measurement method that can improve positioning accuracy. [Solution] A position measuring device 10 is provided with a position calculation unit 22 that calculates the position of observation station A by relative positioning from a satellite signal received by a first satellite signal receiver 12 installed at observation station A to be positioned and a satellite signal received by a second satellite signal receiver 14 installed at a predetermined reference station B. The device further includes an information measurement unit 20 that measures at least one piece of information, such as atmospheric pressure, gravity, and time, at the time the satellite signal is received at observation station A and reference station B. The position calculation unit 22 calculates information on the altitude difference between observation station A and reference station B based on the difference in the information between observation station A and reference station B, and calculates the position of observation station A using the calculated altitude difference information as a constraint.

Description

Technical Field

[0001] The present invention relates to a position measuring device and a position measuring method.

Background Art

[0002] Conventionally, a society has emerged in which a large amount of navigation data is constantly transmitted from many positioning satellites and earth observation satellites. Its uses cover a wide range, such as monitoring daily changes in the ground and structures, and surveying. As an example, a technique using GNSS (Global Navigation Satellite System) is known (see, for example, Patent Document 1).

[0003] As a method for calculating the position from the received data of GNSS positioning satellites, a pseudo-range is calculated by code positioning, and based on the result, an integer value called ambiguity (the number of carrier waves between the positioning satellite and the observation station, that is, the exact distance) is searched for using the carrier phase to determine the final position (see, for example, Patent Document 2).

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, the radio waves from positioning satellites contain various noises due to the influence of the atmosphere and ionosphere, clock errors, and the surrounding environment. The positioning results calculated from these radio waves generally include errors of several centimeters to several tens of meters. Since millimeter-level positioning accuracy is often required at construction sites and the like, improvement of positioning accuracy has been demanded.

[0006] The present invention has been made in view of the above, and aims to provide a position measurement device and a position measurement method that can improve positioning accuracy. [Means for solving the problem]

[0007] To solve the above-mentioned problems and achieve the objective, the position measuring device according to the present invention is a position measuring device comprising a position calculation unit that calculates the position of an observation station by relative positioning from a satellite signal received by a first satellite signal receiver installed at an observation station to be positioned and a satellite signal received by a second satellite signal receiver installed at a predetermined reference station, and further comprising an information measurement unit that measures at least one piece of information, such as atmospheric pressure, gravity, and time, at the time the satellite signal is received at the observation station and the reference station, and the position calculation unit calculates information on the altitude difference between the observation station and the reference station based on the difference in the information between the observation station and the reference station, and calculates the position of the observation station using the calculated altitude difference information as a constraint condition.

[0008] Furthermore, the position measurement method according to the present invention is a position measurement method having a position calculation step of calculating the position of an observation station by relative positioning from a satellite signal received by a first satellite signal receiver installed at an observation station to be positioned and a satellite signal received by a second satellite signal receiver installed at a predetermined reference station, the method further having an information measurement step of measuring at least one piece of information, such as atmospheric pressure, gravity, and time, at the time the satellite signal was received at the observation station and the reference station, and the position calculation step is characterized in that it calculates information on the altitude difference between the observation station and the reference station based on the difference in the information between the observation station and the reference station, and calculates the position of the observation station using the calculated altitude difference information as a constraint condition. [Effects of the Invention]

[0009] The position measuring device according to the present invention includes a position calculation unit that calculates the position of an observation station by relative positioning from a satellite signal received by a first satellite signal receiver installed at an observation station to be positioned and a satellite signal received by a second satellite signal receiver installed at a predetermined reference station, and further includes an information measurement unit that measures at least one piece of information, such as atmospheric pressure, gravity, and time, at the time the satellite signal is received at the observation station and the reference station, and the position calculation unit calculates information on the altitude difference between the observation station and the reference station based on the difference in the information between the observation station and the reference station, and calculates the position of the observation station using the calculated altitude difference information as a constraint condition, thereby improving positioning accuracy.

[0010] Furthermore, the position measurement method according to the present invention is a position measurement method having a position calculation step of calculating the position of an observation station by relative positioning from a satellite signal received by a first satellite signal receiver installed at an observation station to be positioned and a satellite signal received by a second satellite signal receiver installed at a predetermined reference station, and further having an information measurement step of measuring at least one piece of information of atmospheric pressure, gravity, and time when the satellite signal was received at the observation station and the reference station, and the position calculation step calculates information of the altitude difference between the observation station and the reference station based on the difference in the information between the observation station and the reference station, and calculates the position of the observation station using the calculated altitude difference information as a constraint condition, thereby having the effect of improving positioning accuracy. [Brief explanation of the drawing]

[0011] [Figure 1] Figure 1 is a schematic diagram showing an embodiment of the position measuring device according to the present invention. [Figure 2] Figure 2 is a schematic procedure diagram showing an embodiment of the position measurement method according to the present invention. [Modes for carrying out the invention]

[0012] Embodiments of the position measuring device and position measuring method according to the present invention will be described in detail below with reference to the drawings. However, the present invention is not limited to these embodiments.

[0013] As shown in Figure 1, the position measurement device 10 according to an embodiment of the present invention consists of a GNSS receiver 12 installed at observation station A, a GNSS receiver 14 installed at base station B, and a processing terminal 16 that is communicatively connected to the GNSS receivers 12 and 14. This embodiment assumes application to surveying work on buildings and other structures at construction sites.

[0014] Observation station A is installed at the location where the position to be measured is to be measured (for example, the top of a building under construction). Reference station B is a reference location for relative positioning such as differential positioning and real-time kinematic positioning, and is installed, for example, on the ground near the site where radio waves can be received well.

[0015] GNSS receiver 12 is a first satellite signal receiver, and GNSS receiver 14 is a second satellite signal receiver. GNSS receivers 12 and 14 each include a receiving unit 18 that receives satellite signals transmitted from multiple GNSS positioning satellites, and an information measurement unit 20.

[0016] The information measurement unit 20 is a sensor that measures at least one piece of information—atmospheric pressure, gravity, and time—when the GNSS receivers 12 and 14 receive satellite signals. The information measurement unit 20 can be configured using a barometer, gravity (accelerometer), and clock mounted on the GNSS receivers 12 and 14. Alternatively, the information measurement unit 20 may use a separate pressure sensor, gravity (accelerometer), clock, etc., instead of using the barometer, gravity (accelerometer), and clock mounted on the GNSS receivers 12 and 14.

[0017] The processing terminal 16 includes a position calculation unit 22, a position storage unit 24, and an output unit 26.

[0018] The position calculation unit 22 calculates the position of the observation station A by relative positioning from the reception information of the GNSS receivers 12 and 14. At the time of initial setting, the positions of the observation station A and the reference station B are calculated from each of the GNSS receivers 12 and 14 and stored in the position storage unit 24. Thereafter, the position calculation unit 22 calculates the position of the observation station A by relative positioning from the reception information of the GNSS receivers 12 and 14 at each predetermined time, and stores the calculation result in the position storage unit 24 as the measured position. The calculation result can be output to the output unit 26.

[0019] Here, the position calculation unit 22 calculates information on the altitude difference between the observation station A and the reference station B based on the difference in at least one of the information on air pressure, gravity, and time between the observation station A and the reference station B measured by the information measurement unit 20. Then, using the calculated altitude difference information as a constraint condition in the positioning calculation, the position of the observation station A is calculated. For example, in the positioning calculation, the ambiguity included in the carrier phase of the satellite signal may be determined by solving an equation using the altitude difference information as a constraint condition, and the position of the observation station A may be calculated based on the determined ambiguity.

[0020] As described above, in the present embodiment, the altitude difference is calculated using any one of the air pressure, gravity, and time measured by a separate sensor mounted on the GNSS receivers 12 and 14, or the difference between a plurality of information, and this is added as a constraint condition when solving the equation in the positioning calculation in the position calculation unit 22. Thereby, the positioning accuracy in the height direction can be improved.

[0021] In general relative positioning, since information on two points, namely the reference station B which is a fixed point and the observation station A where position measurement is performed, is used, in terms of air pressure, a sensor capable of measuring the total pressure is used to calculate the altitude difference from the air pressure difference between the two points of the observation station A and the reference station B. Also, regarding gravity, if information such as the gravity potential (geoid) and tides is accurately known, it is possible to convert the gravity difference between two points into an altitude difference. Similarly, due to the relativistic effect, since the way time progresses changes due to the gravity difference, a difference in the time of the clocks between two points occurs, enabling conversion into an altitude difference. By using the altitude difference information obtained thereby as a constraint condition during positioning calculation, the positioning accuracy is improved.

[0022] By this method, it becomes possible to perform positioning with a positioning accuracy that could not be achieved by conventional methods, and the applicable range is greatly expanded not limited to construction sites.

[0023] For example, when using a barometer, the altitude difference Δh = h2 - h1 can be calculated by the following formula (1) using the formula of the standard atmosphere.

[0024]

Equation

[0025] Here, h1 is the altitude of the reference station, h2 is the altitude of the observation station, P1 is the pressure at the reference station, P2 is the pressure at the observation station, RT / gM is the scale height, R is the gas constant, T is the temperature of the atmosphere, M is the molar mass of the atmosphere, and g is the acceleration due to gravity. The above can be extended and an equation considering the lapse rate of air temperature may be used.

[0026] When using a gravimeter, the altitude difference Δh can be calculated by the following formula (2).

[0027]

Equation

[0028] Here, r eΔg = g2 - g1 is the gravitational difference between the observation station and the reference station, g1 is the gravitational acceleration at the reference station, g2 is the gravitational acceleration at the observation station, and g0 is the gravitational acceleration at the Earth's surface.

[0029] Next, an example of a position measurement method using the position measurement device 10 described above will be explained. As shown in Figure 2, first, the information measurement units 20 of observation station A and reference station B measure at least one piece of information: atmospheric pressure, gravity, and time when the satellite signal is received (step S1). Next, the position calculation unit 22 calculates the altitude difference between observation station A and reference station B based on the difference in information between observation station A and reference station B (step S2). Finally, the position of observation station A is calculated using the calculated altitude difference as a constraint (step S3). This improves positioning accuracy.

[0030] In the above embodiment, a program for realizing all or part of the functions of the position measuring device 10 may be recorded on a computer-readable recording medium, and the program recorded on this recording medium may be read by a computer and executed to perform the processing of each part.

[0031] Conventional GNSS and similar measurement methods often fail to meet the accuracy requirements in the construction and civil engineering fields. Furthermore, high-precision positioning is required for applications such as autonomous driving and pedestrian flow management. In contrast, this embodiment significantly improves the accuracy of positioning analysis, thereby enhancing positioning accuracy. Moreover, since it can grasp the position of objects and the movement of stationary objects in real time, with millimeter-level positioning accuracy under favorable conditions, it is suitable for position measurement at construction sites and other locations.

[0032] As described above, the position measuring device according to the present invention is a position measuring device comprising a position calculation unit that calculates the position of an observation station by relative positioning from a satellite signal received by a first satellite signal receiver installed at an observation station to be positioned and a satellite signal received by a second satellite signal receiver installed at a predetermined reference station, and further comprising an information measurement unit that measures at least one piece of information, such as atmospheric pressure, gravity, and time, at the time the satellite signal is received at the observation station and the reference station, and the position calculation unit calculates information on the altitude difference between the observation station and the reference station based on the difference in the information between the observation station and the reference station, and calculates the position of the observation station using the calculated altitude difference information as a constraint condition, thereby improving positioning accuracy.

[0033] Furthermore, the position measurement method according to the present invention is a position measurement method having a position calculation step of calculating the position of an observation station by relative positioning from a satellite signal received by a first satellite signal receiver installed at an observation station to be positioned and a satellite signal received by a second satellite signal receiver installed at a predetermined reference station, and further having an information measurement step of measuring at least one piece of information of atmospheric pressure, gravity, and time when the satellite signal was received at the observation station and the reference station, and the position calculation step calculates information of the altitude difference between the observation station and the reference station based on the difference in the information between the observation station and the reference station, and calculates the position of the observation station using the calculated altitude difference information as a constraint condition, thereby improving positioning accuracy.

[0034] Furthermore, the "Sustainable Development Goals (SDGs)" are among the 17 international goals adopted at the UN Summit in September 2015. The position measurement device and position measurement method according to this embodiment can contribute to achieving some of the 17 SDGs, such as Goal 9, "Build resilient infrastructure, promote inclusive and sustainable industrialization and foster innovation." [Industrial applicability]

[0035] As described above, the position measurement device and position measurement method according to the present invention are useful for position measurement at construction sites and the like, and are particularly suitable for improving positioning accuracy. [Explanation of Symbols]

[0036] 10 Position measuring device 12 GNSS receiver (first satellite signal receiver) 14. GNSS receiver (second satellite signal receiver) 16 Processing terminals 18 Receiving Unit 20 Information Measurement Unit 22 Position calculation section 24 Position memory section 26 Output section A Observation Station B reference station

Claims

1. A position measuring device comprising a position calculation unit that calculates the position of an observation station by relative positioning from a satellite signal received by a first satellite signal receiver installed at an observation station to be positioned and a satellite signal received by a second satellite signal receiver installed at a predetermined reference station, The observation station and the reference station are further equipped with an information measuring unit that measures at least one piece of information, such as atmospheric pressure, gravity, and time, when a satellite signal is received. The position measurement device is characterized in that the position calculation unit calculates information on the altitude difference between the observation station and the reference station based on the difference in the information between the observation station and the reference station, and calculates the position of the observation station using the calculated altitude difference information as a constraint condition.

2. A position measurement method comprising a position calculation step of calculating the position of an observation station by relative positioning from a satellite signal received by a first satellite signal receiver installed at an observation station to be positioned and a satellite signal received by a second satellite signal receiver installed at a predetermined reference station, The observation station and the reference station further have an information measurement step of measuring at least one piece of information, such as atmospheric pressure, gravity, and time, when a satellite signal is received. The position calculation step is a position measurement method characterized by calculating information on the altitude difference between the observation station and the reference station based on the difference in the information between the observation station and the reference station, and calculating the position of the observation station using the calculated altitude difference information as a constraint condition.

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