JP7288313B2 - POSITIONING ASSISTANCE DEVICE, POSITIONING ASSISTANCE SYSTEM, POSITIONING SYSTEM AND POSITIONING ASSISTANCE METHOD - Google Patents

Description

The present invention relates to a positioning support device, a positioning support system, a positioning system, and a positioning support method.

In recent years, the use of positioning using GNSS (Global Navigation Satellite System) is rapidly expanding. Positioning using GNSS is hereinafter referred to as GNSS positioning. In smartphones, applications using location information obtained by GNSS positioning are also increasing. Location information obtained by GNSS positioning is also used for automatic driving of vehicles, control of drones, and the like. Furthermore, the momentum toward the realization of an IoT (Internet of Things) society is increasing, and it is expected that IoT devices will also use location information obtained by GNSS positioning.

Along with the expansion of the use of GNSS positioning, consideration is also being given to increasing the accuracy of GNSS positioning. As an example of highly accurate GNSS positioning, RTK (Real Time Kinematic) positioning is known, which performs positioning calculations using the phase of carrier waves from satellites. RTK positioning is used in surveying equipment, automatic driving of vehicles, and the like. In RTK positioning, it is necessary to provide receivers for receiving positioning signals transmitted from satellites at both the reference point and the measurement point, and the position of the reference point must be measured with high accuracy. For this reason, installation and operation of the reference points require costs and man-hours.

As a method that does not require setting a reference point, there is a VRS (Virtual Reference Station) method in which artificial observation data is generated by virtual calculation and transmitted to a user terminal (see Non-Patent Document 1). In the VRS system, first, a user terminal obtains its own position by code positioning using a positioning signal transmitted from a satellite, and transmits the position to a service providing center. Then, the center generates artificial observation data corresponding to the virtual reference point with the position received from the user terminal as the virtual reference point using the observation data of the electronic reference points set by the Geospatial Information Authority of Japan. Send to terminal. The user terminal regards the observation data received from the center as the observation data of the reference point and performs RTK positioning.

Michio Tsuzuki et al., "Real-time positioning by virtual reference point method", Geospatial Information Authority of Japan Jiho No. 96 p39-p44, Geospatial Information Authority of Japan 2001

However, in the VRS system, in order to perform positioning by the VRS system, the user terminal must be registered with the center in advance, and after confirmation of authentication, it is necessary to transmit the approximate location of the user to the center. sends artificial observation data based on the approximate location of the user for each request. Since communication is basically 1:1, the cost for using it is often high. Therefore, there is a problem that general users cannot easily use this service without being conscious of it. With the expansion of the use of the GNSS positioning described above, there is a demand for a technology that allows ordinary users to easily achieve highly accurate positioning without taking the trouble of registration.

The present invention has been made in view of the above, and provides a positioning support device, a positioning support system, a positioning system, and a positioning support method that can easily provide highly accurate positioning to the user without requiring the user's trouble. aim.

In order to solve the above-described problems and achieve the object, the present invention provides a Centimeter Level Augmentation Service (CLAS) transmitted from a Quasi-Zenith Satellite System (QZSS). An observation data generation unit that generates artificial observation data observed at a plurality of predetermined points based on positioning augmentation information, and a communication unit that transmits data based on the artificial observation data to devices corresponding to the points. and.

ADVANTAGE OF THE INVENTION According to this invention, it is effective in being able to provide a user with highly accurate positioning easily, without requiring a user's time and effort.

1 is a diagram showing a configuration example of an entire system including a positioning support system according to an embodiment of the present invention; FIG. FIG. 4 is a diagram for explaining a positioning augmentation signal; FIG. It is a figure which shows the functional structural example of an information processing apparatus. It is a figure which shows the hardware example of an information processing apparatus. FIG. 2 is a diagram showing an example of functional configurations of a base station and a terminal; FIG. FIG. 10 is a diagram showing another configuration example of a terminal; It is a chart figure which shows the operation example of the whole system of an Example. 4 is a flowchart illustrating an example of a positioning support processing procedure executed by an information processing device; FIG. 4 is a schematic diagram showing an example of the relationship between the communicable range of the base station and the positioning accuracy guarantee range of the embodiment; It is a figure which shows the structural example in the case of using artificial observation data and the observation data of a GNSS receiver together. FIG. 4 is a diagram showing a configuration example when the positioning support system transmits artificial observation data directly to terminals; FIG. 12 is a diagram showing a functional configuration example of a terminal in the overall system shown in FIG. 11;

A positioning support device, a positioning support system, a positioning system, and a positioning support method according to embodiments of the present invention will be described below in detail with reference to the drawings. In addition, this invention is not limited by this Example.

FIG. 1 is a diagram showing a configuration example of an overall system (positioning system) including a positioning support system according to an embodiment of the present invention. As shown in FIG. 1 , the measurement support system 1 of the embodiment can receive positioning augmentation signals transmitted from a Quasi-Zenith Satellite System (QZSS) 2 . Also, the measurement support system 1 can receive a positioning augmentation signal transmitted from the ground station 7 . Although FIG. 1 shows an example in which the measurement support system 1 can receive both the positioning augmentation signal transmitted from the QZSS and the positioning augmentation signal transmitted from the ground station 7, only one of them can be received. may be

A positioning augmentation signal is a signal containing positioning augmentation information in Centimeter Level Augmentation Service (CLAS). The positioning augmentation information is information for correcting positioning errors, and is calculated by the ground station 7 based on observation data of electronic reference points and the like. The ground station 7 can transmit a positioning augmentation signal containing positioning augmentation information via a terrestrial line. Also, the ground station 7 transmits a positioning augmentation signal to the quasi-zenith satellite 2 . The quasi-zenith satellite 2 transmits the positioning augmentation signal received from the ground station 7 toward the ground as an L6 signal. Details of the positioning augmentation signal will be described later.

The quasi-zenith satellite 2 transmits a positioning augmentation signal and a positioning signal toward the ground. The positioning signal is at least one of L1 signal, L2 signal and L5 signal, and is a signal including C/A code, navigation message and the like. The positioning satellites 3-1 to 3-m shown in FIG. 1 are GNSS satellites or the like, and are satellites that transmit positioning signals to the ground. m is an arbitrary integer of 3 or more. In addition, although one quasi-zenith satellite 2 is illustrated in FIG. 1, a plurality of quasi-zenith satellites 2 may be used.

By using the positioning augmentation signal, it is possible to achieve centimeter-level positioning accuracy. A decoder is required, and a device that independently performs positioning using the positioning augmentation signal is large and expensive. The distribution destination of the positioning augmentation signal from the ground station 7 is limited, and even if the positioning augmentation signal is received, terminals capable of performing positioning calculations using the positioning augmentation signal are not widespread. On the other hand, surveying instruments and the like capable of performing RTK calculations are already in widespread use, and it is expected that application software for performing RTK calculations will also spread in general-purpose terminals such as smartphones in the future.

In the present embodiment, although the details will be described later, for example, the positioning support system 1 uses positioning augmentation information to set one or more predetermined fixed positions (coordinates) as virtual reference points, and artificially generate observational data. Then, the positioning support system 1 transmits the artificial observation data to the communication device, and the communication device reports the artificial observation data and the coordinates of the virtual reference point. As a result, any terminal that can communicate with the communication device described above can receive highly accurate artificial observation data generated using the positioning augmentation information and the coordinates of the virtual reference point. Therefore, if the terminal has a function capable of performing RTK positioning, highly accurate positioning can be achieved by receiving the above-described highly accurate artificial observation data and the coordinates of the virtual reference point. That is, the terminal can perform highly accurate positioning without preparing an antenna for receiving the positioning augmentation signal transmitted from the quasi-zenith satellite 2 and without having a function of performing calculations using the positioning augmentation signal. can be realized.

In the following, as a specific example, an example will be described in which the above-described communication devices are base stations 5-1 to 5-n in a mobile phone network, and virtual reference points are the coordinates of the base stations 5-1 to 5-n. . n is an arbitrary integer of 1 or more. In the present invention, the coordinates of the virtual reference point need not be exact positions of the base stations 5-1 to 5-n, but may be rough coordinates obtained from map information or the like. Therefore, the base stations 5-1 to 5-n do not need to have a function for precisely obtaining their own positions like reference points in RTK positioning. The base stations 5-1 to 5-n report the coordinates of the virtual reference point corresponding to each and artificial observation data, and the terminals 6-1 and 6-2 receive the reported coordinates of the virtual reference point. and artificial observation data. Hereinafter, when the base stations 5-1 to 5-n are individually indicated without distinction, they are referred to as the base station 5, and when the terminals 6-1 and 6-2 are individually indicated without distinction, they are referred to as the terminal 6. . Similarly, the positioning satellites 3-1 to 3-m are referred to as positioning satellites 3 when they are not distinguished individually. Although two terminals 6 are shown in FIG. 1, the number of terminals 6 is not limited to the example shown in FIG.

The base station 5 and the terminal 6 perform wireless communication according to a communication method specified by the mobile phone network. Communication between the base station 5 and the terminal 6 can use a general method, and since there are no particular restrictions, the description is omitted. Terminal 6 is, for example, a smart phone, a feature phone, a tablet, or a personal computer. The terminal 6 may be an IoT device, a device for automatic driving mounted on a vehicle, or the like.

Next, the positioning augmentation signal will be explained. FIG. 2 is a diagram for explaining the positioning augmentation signal. A large number of electronic reference points have been established throughout Japan. The electronic reference point generates observation data by receiving positioning signals from the positioning satellites 3-1 to 3-m and the quasi-zenith satellite 2. FIG. The coordinates of the electronic reference point are precisely determined. The distribution device 8 collects observation data from each electronic reference point, associates the coordinates of the electronic reference point with the observation data, and distributes them. That is, the observation data distributed from the distribution device 8 is position (coordinate) dependent observation data.

The ground station 7 receives the coordinates of each electronic reference point and the observation data from the distribution device 8 and uses these data to create a position-independent or position-dependent system for correcting errors in positioning calculations. Generate positioning augmentation information that is non-existent data. The positioning augmentation information is, for example, information generated based on a plurality of observation data obtained by observing positioning signals transmitted from positioning satellites at electronic reference points, which are a plurality of observation points. Here, the positioning augmentation information will be explained. Positioning augmentation methods can be broadly divided into OSR (Observation Space Representation) methods that use observation data itself at a fixed position, and SSR (State Space Representation) methods that are position-independent (the position is not fixed). representation) method. The OSR method is a method using position-dependent data, and the SSR method is a method using position-independent data.

Describe location-dependent data. Let u be a variable that identifies the user's receiver, that is, the terminal 6, and p be a variable that identifies each of the positioning satellites 3-1 to 3-m and the quasi-zenith satellite 2 that transmit positioning signals. At this time, the carrier phase of the signal s, which is the positioning signal between the satellite p and the user's receiver u, can be expressed by the following equation (1).

Also, the pseudorange by the signal s between the satellite p and the user's receiver u can be expressed by the following equation (2).

The bias error B _s,up ^can be expressed by the following equation (3).

The carrier phase and pseudorange shown in equations (1) and (2), ie, observation data, are data that depend on the position of the user's receiver u. Therefore, observation data is data that cannot be determined unless the position is determined. On the other hand, position-independent positioning augmentation information is data represented by, for example, a state space representation (SSR). Another example of position-independent positioning augmentation information is the FKP (Flaechen Korrektur Parameter) method. The FKP method is a method using correction data obtained by combining the OSR method and the SSR method. Although the SSR method will be described below as an example, the present invention can also be applied to the case of using FKP method data and other similar position-independent data.

A method of calculating positioning augmentation information of the SSR method will be described. First, based on multiple observation data obtained by observing positioning signals transmitted from positioning satellites at multiple observation points, more specifically, based on observation data from multiple electronic reference points, the state space model A state space vector is obtained by positioning processing using a Kalman filter. Then, among the state space vectors, the common errors for each factor are satellite clock error _δt ^sp , satellite orbital error ^δop (vector), satellite signal bias (satellite circuit signal delay) _δd ^sp , tropospheric propagation error Separate into T _grid ^p , the ionospheric propagation error. Each of these errors has different properties. The satellite clock error δt _s ^p is unpredictable and fast-varying because it is caused by the internal noise of the oscillator. On the other hand, the satellite orbit error δo ^p (vector) is mainly determined by global changes in gravitational potential, atmosphere and solar pressure, so it does not change fast. Ionospheric propagation errors are the most complex part and are generally represented with reduced bandwidth by representing the error factors in a more subdivided manner. Specifically, it is separated into a global part I _{s,polynominal} ^p expressed by a function and a probabilistic part I _s,grid ^p that is satellite/location dependent. The global part I _{s,polynominal} ^p represents the general and smooth nature of the ionosphere. The random error remaining after being represented by the global part I _{s,polynominal} ^p of the ionospheric propagation error is represented as the satellite/location dependent probabilistic part I _s,grid ^p . Thus, error factors are separated based on physical properties. The positioning augmentation information includes information indicative of each error separated as described above. Regarding multipath, it is supposed to be corrected at the terminal 6, and is not included in the modeling here either. The antenna phase center is also corrected separately and is not included in the modeling here either.

For the satellite/location-dependent probabilistic portion I _s,grid ^p of the ionospheric propagation error, an error correction value is defined for each point at approximately 60 km intervals called a grid. The same is true for the tropospheric propagation error T _grid ^p . For I _{s , grid} ^p and T _grid ^p , the entire area of Japan is divided into 12 nets, and the error correction value for each grid is determined for each net. The augmented positioning information includes information about the entire network, and a user using the augmented positioning information performs positioning calculations using the augmented positioning information of the corresponding network and grid when performing positioning.

In addition, the quality of each of the above errors is managed by indicators of accuracy, availability, integrity, and continuity, and the results are included in the positioning augmentation information as SSR URA (User Range Accuracy), SSR STEC, and SSR Tropospheric delay. is

The positioning augmentation information can be considered to indicate the form and coefficients of the function when the bias error B _s, up is represented by f _ssr (t, s, u, ^p ), where t is time. Thus, here t indicates the time of day, s indicates the signal, p indicates the satellite (satellite position), and u indicates the user receiver (user receiver position).

As described above, the positioning augmentation information including the information for correcting the positioning error represented by the state space representation is transmitted from the quasi-zenith satellite 2 via the ground station 7 as the positioning augmentation signal as described above. be.

Next, the positioning support system 1 of this embodiment will be described. The measurement support system 1 includes an antenna 11, a decoder 12 and an information processing device 13, as shown in FIG. Antenna 11 receives a positioning augmentation signal from quasi-zenith satellite 2 and outputs the received signal to decoder 12 . The decoder 12 demodulates (decodes) the signal input from the antenna 11 and outputs augmented positioning information obtained by the demodulation to the information processing device 13 . The information processing device 13 generates artificial observation data at one or more predetermined virtual reference points using the positioning augmentation information, and communicates the artificial observation data with the artificial observation data. It is a positioning support device according to the present invention that transmits to a device.

FIG. 3 is a diagram showing a functional configuration example of the information processing device 13. As shown in FIG. The information processing device 13 includes a communication section 131 , an observation data generation section 132 and a position data storage section 133 . The position data storage unit 133 stores coordinates indicating the positions of the base stations 5-1 to 5-n, which are virtual reference points, as base station position data. As described above, the coordinates of the base stations 5-1 to 5-n may not be precise, and may be obtained from map information or the like. Therefore, for example, the operator of the positioning support system 1 acquires the coordinates of the base stations 5-1 to 5-n from the installation operator of the base stations 5-1 to 5-n, and inputs them to the information processing device 13. Alternatively, the information processing device 13 may acquire the information from a server owned by the installation operator of the base stations 5-1 to 5-n via a communication line. Moreover, when a new base station 5 is added, the coordinates of the base station 5 may be added to the base station position data.

The communication unit 131 communicates with the decoder 12, the ground station 7, the base stations 5-1 to 5-n via the network 4, and the like. Communication between the information processing device 13 and the base stations 5-1 to 5-n is generally performed via a base station controller (not shown), but here the network 4 includes devices such as the base station controller. described as. Communication between the ground station 7 and the information processing device 13 may be performed using a dedicated line or via a public network. The observation data generator 132 generates artificial observation data observed at one or more predetermined fixed points. An example of the one or more predetermined fixed points is the position of the base station 5, but as will be described later, the one or more predetermined fixed points are points other than the position of the base station 5. In some cases. Although details will be described later, the observation data generation unit 132 uses the base station position data, the positioning augmentation information, and the ephemeris included in the navigation message stored in the position data storage unit 133 to generate the base stations 5-1 to 5-5. - Generate artificial observation data corresponding to n. There are no particular restrictions on the method of acquiring ephemeris, and the information processing device 13 may acquire, from a receiver set at an arbitrary location, a navigation message included in a positioning signal received by the receiver. , IGS (International GNSS Service), etc. through the network. The observation data generation unit 132 associates the artificial observation data generated by the observation data generation unit 132 with the coordinates of the base stations 5-1 to 5-n, which are virtual reference points. It is transmitted to the base stations 5-1 to 5-n via the network 4. FIG.

For example, the communication unit 131 transmits data in which n sets of individual data, which is a set of data including coordinates of a virtual reference point and corresponding artificial observation data, are stored. Note that n sets of individual data are transmitted to all of the base stations 5-1 to 5-n, and the base stations 5-1 to 5-n select their own individual data from the n sets of individual data. may be notified. Alternatively, the communication unit 131 may specify the destination of each of the base stations 5-1 to 5-n and transmit the corresponding set of individual data to the base stations 5-1 to 5-n. Alternatively, a base station controller (not shown) may transmit corresponding individual data out of the n sets of individual data to each of the base stations 5-1 to 5-n. By setting the interval between the base stations 5 to be narrower than the effective range of the artificial observation data, the terminal 6 can automatically receive the effective artificial observation data from the nearest base station 5. It becomes possible. In addition, when there are a plurality of base stations 5 within the effective range of artificial observation data, the information processing device 13 does not set a virtual reference point for each base station 5, but rather sets a virtual reference point for these base stations 5. A virtual reference point may be defined, and the same artificial observation data and the coordinates of the virtual reference point may be transmitted to a plurality of base stations 5 .

Next, the hardware configuration of the information processing device 13 will be described. FIG. 4 is a diagram showing a hardware example of the information processing device 13. As shown in FIG. The information processing device 13 is realized by a computer system (computer system) as shown in FIG. As shown in FIG. 4, this computer system comprises a control section 101, an input section 102, a storage section 103, a display section 104, a communication section 105 and an output section 106, which are connected via a system bus 107. there is

In FIG. 4, a control unit 101 is a processor such as a CPU (Central Processing Unit), and executes the positioning assistance program of this embodiment. The input unit 102 is composed of, for example, a keyboard and a mouse, and is used by the user of the computer system to input various information. The storage unit 103 includes various memories such as RAM (Random Access Memory) and ROM (Read Only Memory) and storage devices such as a hard disk, and stores programs to be executed by the control unit 101 and necessary information obtained in the course of processing. store data, etc. The storage unit 103 is also used as a temporary storage area for programs. The display unit 104 includes a display, LCD (liquid crystal display panel), etc., and displays various screens to the user of the computer system. The communication unit 105 is a transmitter and a receiver that carry out communication processing. The output unit 106 is a printer or the like. Note that FIG. 4 is an example, and the configuration of the computer system is not limited to the example in FIG. For example, the computer system need not include output unit 106 .

Here, an operation example of the computer system until the positioning support program of the present embodiment becomes executable will be described. In the computer system having the above-described configuration, for example, a CD (Compact Disc)-ROM or DVD (Digital Versatile Disc)-ROM drive (not shown) stores a positioning support program stored in a CD-ROM or DVD-ROM drive. 103 installed. Then, when the positioning assistance program is executed, the positioning assistance program read from storage unit 103 is stored in a predetermined location of storage unit 103 . In this state, the control unit 101 executes the positioning support processing of this embodiment according to the program stored in the storage unit 103 .

In this embodiment, a program describing the positioning support process is provided using a CD-ROM or DVD-ROM as a recording medium, but the configuration of the computer system, the capacity of the provided program, etc. are not limited to this. Depending on the situation, for example, a program provided via a transmission medium such as the Internet via the communication unit 105 may be used.

A communication unit 131 shown in FIG. 3 is the communication unit 105 shown in FIG. Observation data generation unit 132 shown in FIG. 3 is implemented by control unit 101 and storage unit 103 in FIG. 4, and position data storage unit 133 shown in FIG. 3 is implemented by storage unit 103 in FIG.

Next, configuration examples of the base station 5 and the terminal 6 will be described. FIG. 5 is a diagram showing a functional configuration example of the base station 5 and the terminal 6. As shown in FIG. The base station 5 includes a radio communication section 51 , a notification signal generation section 52 and a communication section 53 . The wireless communication unit 51 performs wireless communication with the terminal 6 . The communication unit 53 communicates via the network 4 . The notification signal generation unit 52 uses artificially generated observation data (or artificially generated observation data associated with coordinates) that the communication unit 53 receives from the information processing device 13 via the network 4. , the positioning assistance data is generated, and the positioning assistance data is notified via the wireless communication unit 51 . The positioning assistance data includes coordinates of the base station 5 and artificial observation data. In addition to the components shown in FIG. 5, the base station 5 generally has a function for allocating radio resources to the terminal 6, a function for realizing call control with the terminal 6, and the like. However, here, the description of the general functions of these base stations is omitted, and the portions related to the present invention will be described.

Further, the terminal 6 includes a wireless communication unit 61, a positioning signal reception unit 62, an RTK calculation unit 63, and a display unit 64, as shown in FIG. The radio communication unit 61 performs radio communication with the base station 5 . The positioning signal receiving unit 62 receives positioning signals transmitted from the positioning satellites 3 - 1 to 3 - m and the quasi-zenith satellite 2 . The RTK calculation unit 63 calculates the position of the terminal 6 by performing RTK calculation using the positioning assistance data received by the wireless communication unit 61 and the positioning signal received by the positioning signal reception unit 62 . Specifically, the RTK calculation unit 63 performs the RTK calculation using the coordinates of the base station 5 and the observation data, which are the positioning support data, as the coordinates of the reference point and the observation data in the RTK calculation. A display unit 64 displays the position calculated by the RTK calculation unit 63 . Alternatively, the terminal 6 may include a calculation unit that performs processing using the position of the terminal 6 calculated by the RTK calculation unit 63 , and this calculation unit may perform calculation using the position of the terminal 6 . The RTK calculation unit 63 is realized by installing application software in the terminal 6, for example.

FIG. 6 is a diagram showing another configuration example of the terminal 6. As shown in FIG. In the example shown in FIG. 5, the terminal 6 itself has the function of performing RTK calculation, but in the example shown in FIG. It has a function of delivering support data to an RTK device 9 having an RTK calculation function. Components having functions similar to those in FIG. 5 are assigned the same reference numerals as those in FIG. 5, and overlapping descriptions are omitted. In the example shown in FIG. 6 , the terminal 6 has a wireless communication section 61 , a device control section 65 and a device communication section 66 . The device control section 65 controls the RTK device 9 . The device communication unit 66 performs wireless communication with the RTK device 9 by, for example, a wireless LAN (Local Area Network) such as Wi-Fi (registered trademark), Bluetooth (registered trademark), or a short-range wireless system such as infrared communication. Alternatively, the device communication unit 66 may perform wired communication with the RTK device 9 . The device control section 65 transmits the positioning assistance data received by the wireless communication section 61 to the RTK device 9 via the device communication section 66 .

The RTK device 9 includes a communication section 91 , an RTK calculation section 92 , an operation control section 93 and a positioning signal reception section 94 . The communication unit 91 communicates with the terminal 6 by the above-described wireless LAN, short-range wireless system, wired communication, or the like. A positioning signal receiving unit 94 receives positioning signals transmitted from the positioning satellites 3 - 1 to 3 - m and the quasi-zenith satellite 2 . The RTK calculation unit 92 calculates the position of the RTK device 9 by performing RTK calculation using the positioning assistance data received by the communication unit 91 and the positioning signal received by the positioning signal reception unit 94 . The motion control section 93 controls the motion of the RTK device 9 based on the position of the RTK device 9 calculated by the RTK calculation section 92 . In the configuration example shown in FIG. 6, the terminal 6 is, for example, a smartphone, and the RTK device 9 is a vehicle that operates automatically, a surveying device, or the like. Note that the RTK device 9 does not have to include the operation control unit 93 when it is a surveying device. In this way, the terminal 6 may be a relay device that distributes the coordinates of the virtual reference point and the observation data to the device having the function of performing RTK calculation. As a result, existing equipment such as surveying equipment having an RTK calculation function can realize highly accurate positioning without requiring the cost and configuration for installing and operating reference points.

Here, hardware configurations of the base station 5, terminal 6 and RTK device 9 will be described. The radio communication unit 51 of the base station 5 is realized by an antenna and communication circuit. The communication unit 53 is implemented by a communication circuit. The notification signal generator 52 is implemented by a processing circuit. The processing circuit may be a dedicated circuit such as FPGA, or may be realized by a processor and memory similar to the control unit 101 and storage unit 103 in FIG. A wireless communication unit 61 of the terminal 6 is realized by an antenna and a communication circuit. The positioning signal receiver 62 is implemented by an antenna and a decoder. The display unit 64 is implemented by an LCD or the like. The RTK calculation unit 63, the device control unit 65, the RTK calculation unit 92, and the operation control unit 93 may each be a dedicated circuit such as an FPGA, or may be a processor similar to the control unit 101 and the storage unit 103 in FIG. It may be realized by memory. The device communication unit 66 and the communication unit 91 are realized by an antenna and a communication circuit, but if a wired line is used, the antenna is not necessary.

Next, the operation of this embodiment will be described. FIG. 7 is a chart showing an operation example of the entire system of this embodiment. In the example shown in FIG. 7, it is assumed that the terminal 6-1 exists within the communicable range of the base station 5-1 and the terminal 6-2 exists within the communicable range of the base station 5-2. As shown in FIG. 7, the positioning support system 1 first receives a positioning augmentation signal (step S1). In FIG. 7, base stations 5-1 and 5-2 are shown as base stations 5 for simplification, but as described above, the number of base stations 5 is arbitrary and the number of base stations 5 is It is not limited to the numbers shown in FIG. Also, here, an example of receiving a positioning augmentation signal from the quasi-zenith satellite 2 will be described, but as described above, the positioning support system 1 may receive positioning augmentation information from the ground station 7 via a ground line.

Next, the positioning support system 1 generates n observation data (artificial observation data) corresponding to each of the base stations 5-1 and 5-2 (step S2). The positioning support system 1 transmits the coordinates and artificial observation data of the base station 5-1 to the base station 5-1, and transmits the coordinates and artificial observation data of the base station 5-2 to the base station 5-2 ( step S3). In step S3, as described above, the positioning support system 1 may transmit individually corresponding data to the base stations 5-1 and 5-2, or the data of all the base stations 5 may be transmitted to the base station 5, The corresponding data may be selected by the base station 5 .

The base station 5-1 reports the coordinates and artificial observation data of the base station 5-1, and the base station 5-2 reports the coordinates and artificial observation data of the base station 5-2 (step S4). The terminal 6-1 receives the coordinates of the base station 5-1 and the artificial observation data transmitted in step S4 from the base station 5-1, and also receives the positioning signal (step S5). The terminal 6-1 performs RTK calculation using the coordinates of the base station 5-1, the artificial observation data, and the positioning signal (step S6). Similarly, the terminal 6-2 receives the coordinates of the base station 5-2 and the artificial observation data, as well as the positioning signal (step S7). The terminal 6-2 performs RTK calculation using the coordinates of the base station 5-2, the artificial observation data, and the positioning signal (step S8).

In the example shown in FIG. 7 above, the example in which the one or more predetermined fixed points is the position of the base station 5 has been described. is not limited to

In addition, in the example shown in FIG. 7, the terminal 6 performs the RTK calculation like the configuration example shown in FIG. In the case of the configuration example shown in FIG. 6, instead of steps S5 to S8 in FIG. Perform RTK operations.

Next, the details of the positioning support processing executed by the information processing device 13 of this embodiment will be described. FIG. 8 is a flow chart showing an example of a positioning support processing procedure executed by the information processing device 13. As shown in FIG. As shown in FIG. 8, first, the observation data generation unit 132 acquires positioning augmentation information from the communication unit 131 (step S11). Note that the communication unit 131 acquires the augmented positioning information by receiving the augmented positioning information from the decoder 12 or the ground station 7 as described above.

The observation data generation unit 132 initializes i, which is a variable indicating the number of the base station 5 to be processed, to i=1 (step S12). The observation data generation unit 132 acquires the coordinates of the i-th base station 5 by reading the coordinates of the i-th base station 5 from the base station position data stored in the position data storage unit 133 (step S13). . The observation data generator 132 uses the positioning augmentation information to generate artificial observation data of the coordinates of the i-th base station 5 (step S14).

Here, an example of a method for generating artificial observation data in step S14 will be described. The artificial observation data is observation data of a virtual reference point that is used instead of the actual observation data of the reference point in the RTK calculation. A virtual reference point means a virtual observation point that is not actually observing, that is, receiving no measurement signal.

The observation equation at the coordinate b of the i-th base station 5, which is the virtual reference point, can be expressed by the following equation (4).

The positioning augmentation information is represented by, for example, f _ssr (t, s, b, p) by the state space model, as described above. Here, t is the time at the time of calculation, s is the signal, and p is all available positioning satellites. Then, the estimated value of the bias error of the coordinate b of the i-th base station 5 can be expressed by the following equation (5).

By giving ε _s,b ^p and substituting equation (5) into equation (4), the observation data generator 132 generates artificial observation data ρ ' _{s, b} ^p can be calculated. The same is true for the carrier phase.

The observation data generation unit 132 also performs crustal deformation correction calculation on the artificial observation data of the i-th base station 5, and converts the artificial observation data of the i-th base station 5 into epoch coordinates. This is because GNSS positioning generally requires the current coordinates of the world geodetic system such as WGS84, but the maps are expressed in epoch coordinates. The surface of the earth is covered with more than ten plates, and the plates move on top of the convection mantle inside the earth at a speed of several centimeters per year. Therefore, the map is created based on the ground position in the epoch, with a certain year as the epoch. If the current coordinates determined by GNSS positioning are to be accurately plotted on the epoch coordinates of the map, crustal deformation correction is required to convert the current coordinates to the epoch coordinates. However, in special cases where the map is represented by the current coordinates or where the current coordinates are required by the application, crustal deformation correction is not necessary. Also, if the terminal has already performed the process of correcting the crustal deformation, the center does not need to correct the crustal deformation. The information processing device 13 may transmit both the coordinates for which the crustal movement correction calculation is performed and the coordinates for which the crustal deformation correction calculation is not performed as the coordinates of the i-th base station 5 to the base stations 5-1 to 5-n. The observation data generator 132 holds the coordinates of the i-th base station 5 and artificial observation data.

Returning to the description of FIG. 8, the observation data generation unit 132 determines whether i=n (step S15). Repeat the process from If i=n (step S15 Yes), the observation data generation unit 132 sends the coordinates of the held base stations 5-1 to 5-n and the corresponding artificial observation data to the communication unit 131. to the base stations 5-1 to 5-n (step S17). The information processing device 13 performs the processing shown in FIG. 8, for example, each time it acquires positioning augmentation information.

The processing procedure shown in FIG. 8 is an example, and the specific processing procedure is not limited to the example shown in FIG. 8 as long as the same result can be obtained.

Further, the information processing device 13 acquires the positioning signal from a receiver installed in or near the base station 5 that receives the positioning signal (not shown), and the observation data generation unit 132 or the function unit (not shown) The navigation message included in the positioning signal may be added to the observation data described above, and the communication unit 131 may transmit it to the base stations 5-1 to 5-n. Alternatively, the base station 5 may transmit the navigation message acquired from the receiver to the terminal 6 without going through the information processing device 13 . Note that the information processing device 13 may acquire navigation messages from an institution such as an IGS via a network, as described above.

The terminal 6, which has received the coordinates of the base station 5 and the artificial observation data from the base station 5, based on the coordinates of the base station 5, the artificial observation data, and the observation data obtained from the positioning signal received by the terminal 6. can perform positioning calculations. The observation equation of terminal 6 can be expressed by the following equation (6).

The difference between the artificial observation data received by the terminal 6 from the base station 5 and the observation data observed by the terminal 6 can be expressed by the following equation (7).

Here, the ionospheric propagation error and the tropospheric propagation error at two adjacent points are almost equal. Also, the satellite orbit error, satellite clock error, and satellite signal bias are errors that are determined for each satellite regardless of the position. Therefore, Equation (7) can be expressed by Equation (8) below. Since ε _s,u ^b is a random error, it can be removed by averaging. Since the positions of the positioning satellites are known based on the positioning signals and the coordinates of the base station 5 are obtained from the base station 5, the remaining unknowns are the errors c _{s, u} A total of four. Therefore, it can be calculated from simultaneous observation equations of observation data based on positioning signals received by the terminal 6 from four or more of the positioning satellites 3-1 to 3-m and the quasi-zenith satellite 2. FIG.

By the above processing, the terminal 6 can obtain the position of the terminal 6 based on the artificial observation data received from the base station 5 .

Note that the VRS method is known as a method for generating observation data of virtual reference points. In the VRS method , first, a terminal performs independent positioning using a positioning signal to calculate a rough self-position, and transmits the self-position to a service provider. The service provider uses the observation data of the electronic reference point to generate the observation data of the virtual reference point with the position received from the terminal as the virtual reference point, and transmits the observation data to the terminal. As a result, the terminal can realize highly accurate positioning by performing RTK calculation using the coordinates of the virtual reference point, observation data, and the received positioning signal. However, in this case, the terminal must be registered with the service provider and send the approximate location of the user to the center after confirmation of authentication. In addition, the center needs to transmit artificial observation data based on the rough position of the user for each request from the user. Since communication is basically 1:1, the cost for using it is often high. There is also a service that distributes the augmented positioning information itself to the terminal, but in this case the terminal needs to have a function of performing processing using the augmented positioning information.

In this embodiment, by using the coordinates of base stations 5-1 to 5-n installed at predetermined positions instead of the positions of individual terminals 6 as virtual reference points, many calculations can be performed in one calculation. Information necessary for highly accurate positioning can be transmitted to the terminal 6 . Also, the terminal 6 of the present embodiment only needs to have the function of performing RTK calculation, and does not need to have the function of performing processing using positioning augmentation information.

FIG. 9 is a schematic diagram showing an example of the relationship between the communicable range and the positioning accuracy guarantee range of the base stations 5-1 and 5-2 of this embodiment. The communicable ranges 100-1 and 100-2 shown in FIG. 9 are communicable ranges corresponding to the base stations 5-1 and 5-2, respectively. The accuracy guarantee range 101-1 indicates a range in which positioning accuracy above a certain level is compensated using the coordinates of the base station 5-1 reported from the base station 5-1 and the observation data. The accuracy guarantee range 101-2 indicates a range in which positioning accuracy above a certain level is guaranteed using the coordinates of the base station 5-2 reported from the base station 5-2 and the observation data. Although it depends on the form and type of communication of the base stations 5-1 and 5-2 and the accuracy to be guaranteed, the range in which the accuracy of positioning is guaranteed is generally up to about 10 km from the reference point, and the communicable range is the base station. It is about 5 km from In this way, the guaranteed accuracy range is generally wider than the communicable range. Therefore, for example, if the terminal 6 can communicate with the base station 5-1, the terminal 6 can automatically perform positioning using the coordinates of the base station 5-1 and the observation data reported from the base station 5-1. positioning accuracy is guaranteed.

In the example of FIG. 9, terminals 6-1 and 6-2 exist within the communicable range 100-1 of the base station 5-1 and can receive the coordinates and observation data of the base station 5-1. The positions where the terminals 6-1 and 6-2 exist are also within the accuracy assurance range 101-1. Therefore, the terminals 6-1 and 6-2 perform positioning using the information transmitted from the base station 5-1, thereby automatically guaranteeing the positioning accuracy. Similarly, the terminal 6-3 exists within the communicable range 100-2 of the base station 5-2 and can receive the coordinates and observation data of the base station 5-2. Since the position where the terminal 6-3 exists is also within the accuracy assurance range 101-2, the positioning accuracy of the terminal 6-3 is guaranteed. On the other hand, the terminal 6-4 cannot communicate with either the base station 5-1 or the base station 5-2. Also, the terminal 6-4 is not within any of the guaranteed accuracy ranges 101-1 and 101-2. In such a case, the terminal 6-4 can communicate with the base stations 5-1 and 5-2, although positioning based on information received from the base stations 5-1 and 5-2 does not guarantee accuracy. Therefore, there is no problem with positioning accuracy. Although not shown, if there is another base station 5 capable of communicating with the terminal 6-4 near the terminal 6-4, the terminal 6-4 can perform high-precision communication based on the information received from this base station 5. positioning can be realized. In general, a large number of base stations 5 are arranged so that continuous communication is possible even with mobile terminals 6 . Also, the base station 5 with which the terminal 6 can communicate is generally the closest base station 5 to the terminal 6 . On the other hand, the accuracy of positioning in RTK calculation deteriorates as the distance from the reference point increases. The present embodiment can effectively utilize such characteristics of the base station 5 and positioning characteristics to easily provide the terminal 6 with highly accurate positioning. Since the interval between the base stations 5 is usually set narrower than the effective range of artificial observation data, the user terminal automatically receives effective artificial observation data from the nearest base station 5. becomes possible. Note that, contrary to the example shown in FIG. 9, when the interval between the base stations 5 is larger than the effective range of the artificial observation data, one base station 5 and one adjacent base station 5 each have one The above virtual reference points (referred to as inter-base-station virtual reference points) may be provided. In this case, the information processing device 13 generates artificial observation data corresponding to these inter-base-station virtual reference points, and the above-mentioned one base station 5 is an artificial observation data corresponding to the coordinates of the inter-base-station virtual reference points. It suffices to distribute the relevant observation data. The terminal 6 selects the nearest artificial observation data from among the virtual reference points distributed from the base station 5 and one or more inter-base-station virtual reference points. In this way, the one or more predetermined fixed points for which artificial observation data is generated may be arbitrary virtual reference points between the plurality of base stations 5 .

In the example of FIG. 9, the effective range of the artificial observation data and the effective range of the base station 5 are 1:1. is included, the information processing device 13 determines a representative virtual reference point, generates artificial observation data corresponding to this virtual reference point, and distributes the same artificial observation data to the plurality of base stations 5 as described above. You may transmit the physical observation data and the coordinates of the virtual reference point. This reduces the load of generating artificial observation data. That is, one or more predetermined fixed points for which artificial observation data is generated may be virtual reference points representing a plurality of base stations 5 .

FIG. 10 is a diagram showing a configuration example in which artificial observation data and observation data from a GNSS receiver are used together. In the example shown in FIG. 10, the overall system includes a positioning support system 1a instead of the positioning support system 1 of FIG. The configuration other than these is the same as the configuration example shown in FIG. In the example shown in FIG. 10, actual observation data, which is observation data received by the GNSS receiver 202 via the antenna 201, is sent by the base station 5-1 to the information processing device 13a.

The information processing device 13a has an observation data storage unit 134, a positioning calculation unit 135, and a smoothing unit 1136 added to the information processing device 13 shown in FIG. The communication unit 131 stores the actual observation data received from the base station 5-1 in the observation data storage unit 134. FIG. Note that information indicating the date and time of observation is added to the actual observation data. The observation data generation unit 132 generates artificial observation data corresponding to each virtual reference point as described above, and stores the data together with the corresponding time in the observation data storage unit 134 as artificial observation data. In this manner, the observation data storage unit 134 accumulates actual observation data and artificial observation data. Observation data storage unit 134 is implemented by storage unit 103 shown in FIG. 4, and positioning calculation unit 135 and smoothing unit 136 are implemented by control unit 101 and storage unit 103. FIG.

The positioning calculation unit 135 calculates the position of the GNSS receiver 202 (the phase center of the antenna 201) using the actual observation data and the artificial observation data stored in the observation data storage unit 134. FIG. Specifically, the positioning calculation unit 135 performs positioning calculation using the actual observation data and artificial observation data at the same time corresponding to the actual observation data. The smoothing unit 136 averages the positioning results, that is, the positions calculated by the positioning calculation unit 135 for a predetermined period, and outputs the coordinate values obtained by the averaging process to the communication unit 131 . For example, the smoothing unit 136 performs smoothing by averaging data for about one hour to one day of the positions calculated by the positioning calculation unit 135 . This smoothing removes random noise and bias components to improve accuracy. The accurate coordinate values, which are highly accurate positions calculated by the smoothing unit 136, and the latest actual observation data are transmitted to the base station 5-1 via the communication unit 131. FIG. As a result, the accurate coordinates of the GNSS receiver 202 can be obtained without incurring the cost of surveying, etc., and the coordinate system of the position of the GNSS receiver 202 is obtained by a plurality of observation data for which the positioning augmentation information is generated. It is easily possible to match the coordinate system of the observation point. Although FIG. 10 shows an example in which the antenna 201 and the GNSS receiver 202 are connected to the base station 5-1, the antenna 201 and the GNSS receiver 202 are connected to all of the base stations 5-1 to 5-n. may be connected to similarly distribute highly accurate position and actual observation data, or the antenna 201 and the GNSS receiver 202 may be connected to some of the base stations 5-1 to 5-n. Similarly, high-precision position and actual observation data may be distributed. Further, the transmission of the actual observation data to the information processing device 13a may be performed not via the base station 5 but via another route. Further, the observation data storage unit 134 may be provided in a device different from the information processing device 13a, or the positioning calculation unit 135 and the smoothing unit 136 may be provided in a device different from the information processing device 13a. good.

In the example described above, the information processing device 13 generates the artificial observation data, subtracts the geometric distance between the virtual reference point and the satellite from the artificial observation data, and obtains the data from the base station 5-1. to 5-n. That is, the information processing device 13 may transmit data obtained by processing artificial observation data in some way to the base stations 5-1 to 5-n. The artificial observation data itself and the data generated using the artificial observation data are collectively referred to as data based on the artificial observation data.

In the example described above, the information processing device 13 associates the coordinates of the base stations 5-1 to 5-n with the artificial observation data and transmits them to the base stations 5-1 to 5-n. are known in advance between the base stations 5-1 to 5-n and the information processing device 13, and the information processing device 13 transmits only artificial observation data to the base stations 5-1 to 5-n. good.

In addition, in the terminal 6, so that the RTK calculation can be easily performed, the observation data generation unit 132 formats the standard format standardized in the RTK calculation, the standard format in the RTK reference station, etc., and communicates the artificial observation data You may output to the part 131. FIG. A standard format standardized in RTK calculations, a standard format in an RTK reference station, and the like are collectively referred to as a standard format in RTK.

In addition, if the terminal 6 is equipped with a high-performance antenna for receiving the positioning signal, the coordinates of the base station 5 and the artificial observation data received from the base station 5 can be used to obtain high-precision millimeter-level data. positioning can be realized. That is, according to the present embodiment, it is possible to achieve positioning accuracy that is dependent on the equipment provided in the terminal 6 in the range from millimeter class to meter class. According to the desired positioning accuracy, the user selects an expensive device when high-precision positioning is desired, and selects an appropriate device when low cost is prioritized even if the accuracy is somewhat inferior. can be done. As a result, even if the same information transmitted from the base station 5 is used, the positioning accuracy of the terminal 6 may differ.

Further, in the above description, all of the positioning augmentation information is used to generate the artificial observation data, but part of the positioning augmentation information may be used to generate the artificial observation data. In that case, the processing speed can be increased, although the positioning accuracy may deteriorate to some extent.

In the example described above, the positioning support system 1 uses the base stations 5-1 to 5-n as virtual reference points. A communication device may be used instead of the base stations 5-1 to 5-n.

In the example described above, one or more predetermined points are the positions of the base station 5, and the communication unit 131 transmits artificial observation data to the base station 5 as a device corresponding to these points. . The present invention is not limited to this example, and can also be applied when one or more predetermined points are the positions of devices such as terminals. That is, one or more predetermined points may be the terminal or positions near the terminal, and the artificial observation data may be transmitted to this terminal. FIG. 11 is a diagram showing a configuration example when the positioning support system transmits artificial observation data directly to terminals. A positioning support system 1b shown in FIG. 11 is the same as the positioning support system 1 shown in FIG. The information processing device 13b has a configuration in which the position data storage unit 133 is removed from the configuration of the information processing device 13 shown in FIG. In the information processing device 13b, the communication unit 131 receives from the terminal 6a the approximate position of the terminal 6a or the position near the terminal 6a acquired by the terminal 6a by some means. The observation data generation unit 132 of the information processing device 13b generates artificial observation data using the position received by the communication unit 131 as a virtual reference point in the same manner as in the case of the base station 5 described above. observation data to the terminal 6a.

FIG. 12 is a diagram showing a functional configuration example of the terminal 6a in the overall system shown in FIG. A terminal 6a has a positioning calculation unit 68 added to the terminal 6 shown in FIG. The positioning calculation unit 68 performs independent positioning calculation using the positioning signal received by the positioning signal receiving unit 62, and transmits the position obtained by the independent positioning calculation to the information processing device 13b via the communication unit 67. Operations of the terminal 6a other than those described above are the same as those of the terminal 6 shown in FIG.

As described above, in this embodiment, the positioning support system 1 typically calculates a plurality of pieces of artificial observation data at one time. In addition, the number of artificial observation data to be calculated at one time may be one.

The above-described embodiment is only an example, and is not limited to the above-described example, and the above-described configuration and operation may be combined. may be changed.

1, 1a, 1b positioning support system, 2 quasi-zenith satellite, 3-1 to 3-m positioning satellite, 4 network, 5, 5-1 to 5-n base station, 6, 6-1 to 6-m terminal, 7 ground station, 8 distribution device, 9 RTK device, 11, 201 antenna, 12 decoder, 13, 13a, 13b information processing device, 51 wireless communication unit, 52 notification signal generation unit, 53, 67, 91, 131 communication unit, 61 wireless communication unit, 62, 94 positioning signal receiving unit, 63, 92 RTK calculation unit, 64 display unit, 65 device control unit, 66 device communication unit, 68 positioning calculation unit, 93 operation control unit, 100-1, 100- 2 communicable range, 101-1, 101-2 accuracy assurance range, 132 observation data generation unit, 133 position data storage unit, 202 GNSS receiver.

Claims (13)

an observation data generation unit that generates artificial observation data observed at a plurality of predetermined points based on the CLAS positioning augmentation information transmitted from the quasi-zenith satellite system ;
a communication unit that transmits data based on the artificial observation data to a device corresponding to the point;
A positioning support device comprising: 2. The positioning support device according to claim 1 , wherein the communication unit transmits the coordinates of the corresponding point along with the artificial observation data to the device. 3. The positioning support device according to claim 1 , wherein the data based on the artificial observation data is the artificial observation data itself. 3. The positioning support device according to claim 1 , wherein the data based on the artificial observation data is a value obtained by subtracting the geometric distance between the point and the positioning satellite from the artificial observation data. 5. The positioning support device according to any one of claims 1 to 4 , wherein said communication unit further transmits a navigation message corresponding to said point to a device corresponding to said point. The plurality of points are positions of base stations of a mobile phone network,
The observation data generation unit generates the artificial observation data for each of the base stations using predetermined coordinates of a plurality of base stations,
The positioning support device according to any one of claims 1 to 5 , wherein the device corresponding to the point is the base station. The positioning support device according to any one of claims 1 to 6 , wherein the observation data generator formats the artificial observation data into a standard format for real-time kinematic positioning. The observation data generation unit performs crustal deformation correction calculation on the artificial observation data,
The positioning support device according to any one of claims 1 to 7 , wherein the communication unit transmits data based on the artificial observation data after crustal deformation correction calculation to a device corresponding to the point. . Obtaining actual observation data, which is observation data of positioning signals, from a receiver installed at an observation point corresponding to one or more of a plurality of predetermined points,
Positioning calculation is performed using the actual observation data and the artificial observation data at the same time corresponding to the actual observation data, and the positioning results of the positioning calculation are averaged using a predetermined period of time, and the averaging process is performed. 9. The positioning support device according to any one of claims 1 to 8 , wherein the coordinate values obtained by are transmitted to a device corresponding to said point as an accurate coordinate value of said corresponding point. 10. The artificial observation data according to any one of claims 1 to 9 , wherein the observation data generation unit generates the artificial observation data using some subtype messages of the CLAS positioning augmentation information. Positioning support device. An antenna for receiving a signal including CLAS augmentation information transmitted from a quasi-zenith satellite system ;
a decoder that outputs the CLAS positioning augmentation information by decoding the signal;
The positioning support device according to any one of claims 1 to 10 , wherein the CLAS positioning augmentation information is input from the decoder;
A positioning support system comprising: A positioning support device according to any one of claims 1 to 10 ;
a base station that receives data based on the artificial observation data from the positioning support device and notifies the data based on the artificial observation data and the coordinates of the corresponding point;
a terminal that calculates its own position by performing real-time kinematic calculation using data based on the coordinates of the point received from the base station and the artificial observation data;
A positioning system comprising: Based on the CLAS positioning augmentation information transmitted from the quasi-zenith satellite system , the positioning support device uses the positions of a plurality of base stations of the mobile phone network as virtual points for each point to obtain artificial observation data observed at the points. an observation data generation step to generate;
a first transmission step in which the positioning support device transmits data based on the artificial observation data to the base station corresponding to the point;
a second transmission step in which the base station transmits the data based on the artificial observation data and the coordinates of the corresponding point to the terminal;
A positioning support method comprising:

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