JP2011237205A - Monitoring station, control method, wide area augmentation system and control program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a monitoring station capable of installing a monitoring station constituting a wide area augmentation system on a moving object, and to provide a control method, a wide area augmentation system, and a control program.SOLUTION: A monitoring station of a wide area augmentation system comprises: detection means for detecting a position of a self-monitoring station and outputting the position as position information; and transmission means for transmitting the input position information.

Description

  The present invention relates to a monitoring station, a control method, a wide area reinforcement system, and a control program.

  As GNSS (Global Navigation Satelite System: Satellite Navigation System), for example, GPS (Global Positioning System) developed in the United States and GLONASS (Global Orbiting Navigation System) developed in Russia are known. For example, GPS positioning is performed using a pseudorange between a plurality of satellites and a receiver position. The pseudo distance is defined as the time difference Δt between the transmission time of the GPS signal and the reception time at the receiver multiplied by the speed of light c. The receiver calculates its own position based on the position and pseudorange for each satellite. Actually, the pseudo distance includes a predetermined amount of error. Examples of errors include errors due to radio wave delays in the ionosphere and troposphere, clock errors of satellites and receivers, errors of satellite orbits, and errors due to multipaths. Therefore, the positioning accuracy of GPS is generally 10 to 20 m.

  By the way, currently, a proposal to use such a GNSS for, for example, taking off and landing of an aircraft is being studied. In this case, it is necessary to improve the detection accuracy and reliability of GNSS. And the reinforcement system which reinforces the detection precision and reliability of GNSS is a GNSS navigation reinforcement system. In particular, a reinforcement system that uses satellites and is intended to reinforce a wide area is called a wide area reinforcement system or SBAS (Satellite Based Augmentation System).

  For example, as described in Patent Document 1, the SBAS is composed of an SBAS satellite (wide area reinforcement satellite) and a plurality of monitoring stations and control stations installed on the ground. The SBAS satellite is a satellite that provides wide-area reinforcement information to the user. Each monitoring station receives observation data from each of a GNSS satellite (eg, a GPS satellite) and an SBAS satellite. The control station collects observation data of each monitoring station and creates reinforcement information (also called a reinforcement message) based on the observation data. Examples of the reinforcement information include pseudorange error information (GNSS satellite and receiver distance correction information), reliability information, and SBAS satellite and receiver pseudorange information. The reinforcement information is provided to the user's receiver via the SBAS satellite. Thereby, for example, it is possible to perform positioning with higher accuracy than when positioning only with GPS. For example, it is assumed that positioning in units of several meters can be performed.

JP 2007-171082 A

  In general SBAS as disclosed in Patent Document 1, in order to obtain highly accurate reinforcement information, it is necessary to know the position of each monitoring station accurately. On the other hand, since the monitoring station of SBAS did not have the function of surveying its own position, it was assumed that the position of the monitoring station did not change and was fixed (in other words, the monitoring station performed the initial surveying). It was assumed that there was no change from the time position). Therefore, it has been difficult to install a monitoring station on a moving object on the sea where the position of a ship, a buoy or the like is difficult to determine.

  Here, generally, the range in which highly accurate reinforcement information can be provided is an area surrounded by a plurality of monitoring stations. Therefore, highly accurate reinforcement information can be provided in the inland area surrounded by a plurality of monitoring stations. However, as described above, because the monitoring station cannot be installed on the sea, it is difficult to provide highly accurate reinforcement information in coastal areas that are difficult to be surrounded by a plurality of monitoring stations, or the reinforcement information itself cannot be provided. May not be available.

  An object of this invention is to provide the monitoring station which can install the monitoring station which comprises a wide area reinforcement system in the moving object, a control method, a wide area reinforcement system, and a control program.

  The monitoring station of the present invention is a monitoring station of a wide area reinforcement system, and includes a detecting unit that detects the position of the own monitoring station and outputs the position as position information, and a transmission unit that transmits the input position information. .

  The control method of the present invention is a control method for a monitoring station of a wide area reinforcement system, detects the position of the own monitoring station, and transmits the detected position as position information.

  The wide area reinforcement system of the present invention includes a wide area reinforcement satellite and a monitoring station that receives at least a signal of the wide area reinforcement satellite, and the monitoring station detects a position of the own monitoring station and outputs the position information as detection information. Means, and transmission means for transmitting the input position information.

  The control program of the present invention is a control program for a monitoring station of a wide area reinforcement system, and performs processing for detecting the position of the own monitoring station and processing for transmitting the detected position as position information to the computer of the monitoring station. Let it run.

  According to the present invention, it is possible to install a monitoring station constituting a wide area reinforcement system on a moving object.

It is a block diagram for demonstrating the structural example of the monitoring station which concerns on the 1st Embodiment of this invention. It is a block diagram for demonstrating the structural example of the wide area reinforcement system (SBAS) which concerns on the 2nd Embodiment of this invention. It is a block diagram for demonstrating the structural example of the ground side system shown in FIG. 4 is a flowchart for explaining an operation example of each monitoring station shown in FIG. 3. It is a flowchart for demonstrating the operation example of the control station shown in FIG.

[First Embodiment]
FIG. 1 is a block diagram for explaining a configuration example of a monitoring station 200 according to the first embodiment of the present invention. The monitoring station 200 is a monitoring station of the wide area reinforcement system, and includes a detection unit 202 (detection unit) that detects the position of the own monitoring station 200 and a transmission unit 204 (transmission unit) that transmits the detected position information. Prepare. The transmission unit 204 transmits the position information to a control station (not shown in FIG. 1) of the wide area reinforcement system.

  As described above, since the monitoring station 200 according to the first embodiment includes the detection unit 202 that detects its own position, the control station can detect the position of the monitoring station 200 even if the position of the monitoring station 200 changes. Can be grasped. Therefore, the position of the monitoring station 200 does not need to be fixed, and can be installed on a moving object on the sea where the position of a ship, a buoy or the like is difficult to be determined.

  Since it is possible to set up a monitoring station on the sea, it is possible to build an environment surrounded by multiple monitoring stations even in the coastal area, providing highly accurate reinforcement information to the coastal area. It becomes possible.

[Second Embodiment]
FIG. 2 is a block diagram for explaining a configuration example of a wide area reinforcement system (hereinafter referred to as SBAS) 10 according to an embodiment of the present invention. The SBAS 10 is a reinforcing system that reinforces the detection accuracy and reliability of a GNSS (Global Navigation Satellite System). In the following description, GPS (Global Positioning System) is taken as an example of GNSS. Of course, the GNSS is not limited to the GPS, and may be another system, for example, a GLONASS (GL Orbiting Navigation Satellite System).

  The SBAS 10 includes an SBAS satellite (wide area reinforcement satellite) 12 and a ground side system 14. The ground side system 14 includes a plurality of monitoring stations 16-1 to 16-n and a control station 18. Each of the monitoring stations 16-1 to 16-n receives the GPS satellite signal D1 from the plurality of GPS satellites 100 and receives the SBAS satellite signal D2 from the SBAS satellite 12. Each monitoring station 16-1 to 16-n, on the other hand, detects its own position. Each of the monitoring stations 16-1 to 16-n has a GPS satellite signal D1 (including predetermined information calculated based on D1) and an SBAS satellite signal D2 (predetermined information calculated based on D2) at a predetermined timing. And monitoring station data D3 including its own location information is transmitted to the control station 18. The control station 18 obtains the reinforcement message D4 based on each monitoring station data D3 collected from each monitoring station 16-1 to 16-n. The reinforcement message D4 is provided to the user receiver 110 via the SBAS satellite 12.

  FIG. 3 is a block diagram for explaining a configuration example of the ground side system 14 shown in FIG.

  Each of the monitoring stations 16-1 to 16-n includes a receiving unit 20, a reference frequency oscillator 22, a detecting unit 24 (detecting unit), a position recording unit 26 (recording unit), a data processing unit 28, and data transmission. Unit 30 (transmission means).

  The receiving unit 20 receives GPS satellite signals D1 from a plurality of GPS satellites 100. The GPS satellite signal D1 includes at least the Ephemeris and Almanac of the GPS satellite 100. The receiving unit 20 calculates the pseudorange and the carrier wave phase of each GPS satellite 100 based on each GPS satellite signal D1. For each GPS satellite 100, the receiving unit 20 creates “first observation data” including the GPS satellite signal D1 (including at least the ephemeris), the calculated pseudorange, and the carrier phase, and a predetermined recording unit (non-recording unit). Record in the figure).

  The receiving unit 20 also receives the SBAS satellite signal D2 from the SBAS satellite 12. The SBAS satellite signal D2 includes a wide area reinforcement message. The wide-area augmentation message includes at least the SBAS satellite 12 ephemeris and almanac. The receiving unit 20 calculates the pseudorange and carrier phase of the SBAS satellite 12 based on the SBAS satellite signal D2. The receiving unit 20 creates “second observation data” including a wide-area reinforcement message (including at least an ephemeris) of the SBAS satellite signal D2 and the calculated pseudorange and carrier phase, and a predetermined recording unit (not shown). To record.

  The reference frequency oscillator 22 supplies an oscillation signal having a reference frequency to the receiving unit 20 in order to improve the reception accuracy of each satellite information. The reference frequency oscillator 22 may be a cesium oscillator, for example.

  The detection unit 24 detects the position of the own monitoring station. The position detection method in the detection unit 24 may be any detection method as long as the position of the own monitoring station can be detected. For example, position detection using RTK (Real Time Kinetic), position detection combining an accelerometer and a gyro, or optical position detection may be employed. In order to improve the accuracy of the reinforcement information, the detection unit 24 preferably has an accuracy capable of detecting the position in units of several centimeters (centimeters), for example. Moreover, the detection part 24 can detect the absolute position or relative position of the own monitoring station, for example. Furthermore, the detection unit 24 may detect the position of the monitoring station when the monitoring station receives the SBAS satellite signal D2 from the SBAS satellite 12. Alternatively, the detection unit 24 continuously detects the position of the monitoring station at a predetermined cycle, and records at least the most recently detected position in a predetermined recording unit (specifically, the position recording unit 26). it can. The detection cycle in this case is preferably set shorter than the reception cycle of the SBAS satellite signal D2. Thereby, a position substantially close to the actual position of the monitoring stations 16-1 to 16-n at the time of receiving the SBAS satellite signal D2 can be acquired.

  The position recording unit 26 records the position of the self-monitoring station detected by the detection unit 24, reads the position information at a predetermined timing (for example, timing when the SBAS satellite signal D2 is received), and reads the read position information. To the data processing unit 28. Here, when the detection unit 24 detects the absolute position of the own monitoring station, the position recording unit 26 records the detected value itself. On the other hand, when the detection unit 24 detects the relative position of the own monitoring station, the position recording unit 26 sets the detected value (that is, relative) to the recorded value (that is, the absolute position nearest to the own monitoring station). After adding (position), the position is recorded as a new absolute position of the own monitoring station.

  The data processing unit 28 reads the position information of the newest self-monitoring station recorded in the position recording unit 26 at a predetermined timing (for example, the timing at which the SBAS satellite signal D2 is received). Alternatively, the data processing unit 28 can drive the detection unit 24 at the timing and acquire position information at that time. Then, the data processing unit 28 creates monitoring station data D3 including the position information and the first observation data and the second observation data, and transmits the monitoring station data D3 to the data transmission unit 30.

  The data transmission unit 30 converts the monitoring station data D3 into predetermined format data, and transmits the converted data to the control station 18. The communication between the data transmission unit 30 and the data reception unit 40 of the control station 18 may be wired communication or wireless communication. Examples of wired communication include a dedicated telephone line, a LAN (Local Area Network), optical communication, and the like. On the other hand, examples of wireless communication include a cellular network, a satellite line, and a wireless LAN.

  The control station 18 includes a data receiving unit 40, a monitoring station position recording unit 42, each satellite position calculating unit 44, a pseudorange error calculating unit 46, and a reinforcement message creating unit 48.

  The data receiving unit 40 receives each monitoring station data D3 from each monitoring station 16-1 to 16-n. The monitoring station position recording unit 42 records the position information of each monitoring station 16-1 to 16-n included in each monitoring station data D3. That is, the latest position of each of the monitoring stations 16-1 to 16-n is recorded in the monitoring station position recording unit 42. Each satellite position calculation unit 44 obtains the position of each GPS satellite 100 and SBAS satellite 12 based on each monitoring station data D3. The pseudorange error calculator 46 calculates the pseudorange error of each GPS satellite 100 based on the calculated position information of each satellite and each monitoring station data D3. The reinforcement message creation unit 48 creates the reinforcement message D4 including at least the pseudo distance error.

  FIG. 4 is a flowchart for explaining an operation example of each of the monitoring stations 16-1 to 16-n shown in FIG. First, the receiving unit 20 receives GPS satellite signals D1 from a plurality of GPS satellites 100 (step S10). The receiving unit 20 calculates the pseudorange and the carrier wave phase of each GPS satellite 100 based on each GPS satellite signal D1. For each GPS satellite 100, the receiving unit 20 creates “first observation data” including the GPS satellite signal D1 (including at least the ephemeris), the calculated pseudorange and the carrier phase, and a predetermined recording unit (not shown). ).

  The detection unit 24 detects the position of the self-monitoring station and records the detection result in the position recording unit 26 (step S11). In the present embodiment, it is assumed that the detection cycle in the detection unit 24 is set shorter than the reception cycle of the SBAS satellite signal D2.

  The receiving unit 20 determines whether or not the SBAS satellite signal D2 is received from the SBAS satellite 12 (step S12). If the SBAS satellite signal D2 is not received (No determination in step S12), the processes in steps S10 and S11 are repeated. On the other hand, when the SBAS satellite signal D2 is received (in the case of Yes determination in step S12), the receiving unit 20 executes a reception process of the SBAS satellite signal D2 (step S13). Specifically, the receiving unit 20 calculates the pseudorange and carrier phase of the SBAS satellite 12 based on the SBAS satellite signal D2. The receiving unit 20 creates “second observation data” including the wide-area reinforcement message (including at least the ephemeris) of the SBAS satellite signal D2, the calculated pseudorange and the carrier phase, and sends it to a predetermined recording unit (not shown). Record.

  The data processing unit 28 reads the first observation data and the second observation data from each predetermined storage unit, and reads the current position information of the own monitoring station from the position recording unit 26. Then, the data processing unit 28 creates monitoring station data D3 including the first observation data, the second observation data, and the current position information of the own monitoring station, and sends it to the control station 18 via the data transmission unit 30. Transmit (step S14).

  FIG. 5 is a flowchart for explaining an operation example of the control station 18 shown in FIG. The pseudorange error calculation unit 46 receives each monitoring station data D3 from each monitoring station 16-1 to 16-n via the data receiving unit 40 (step S20). The pseudo distance error calculation unit 46 transmits the position information of each of the monitoring stations 16-1 to 16-n included in each of the monitoring station data D3 to the monitoring station position recording unit 42. The monitoring station position recording unit 42 records the position information of each of the monitoring stations 16-1 to 16-n (Step S21). On the other hand, the pseudorange error calculation unit 46 obtains related information (ephemeris, pseudorange, and carrier phase) about each GPS satellite 100 and related information (ephemeris, pseudorange, and carrier phase) about the SBAS satellite 12. , To each satellite position calculation unit 44. Each satellite position calculation unit 44 calculates each position of each GPS satellite 100 and SBAS satellite 12 based on each related information (step S22), and transmits the calculation result to the pseudorange error calculation unit 46. The pseudorange error calculation unit 46 calculates the pseudorange error of each GPS satellite 100 based on the calculation result of each satellite position calculation unit 44 (that is, the position information of each satellite) and the monitoring station data D3 (step S23). . Specifically, first, the pseudo distance error calculation unit 46 calculates the calculation distance based on the position information of each of the monitoring stations 16-1 to 16-n recorded in the monitoring station position recording unit 42 and the GPS ephemeris. . Next, the pseudo distance error calculation unit 46 calculates the difference between the calculated distance and the pseudo distance, and sets this as the pseudo distance error. The calculated pseudo distance error can be decomposed into, for example, an ionospheric error, a long-term error, and a light speed error. The reinforcement message creation unit 48 creates the reinforcement message D4 including the pseudorange error and the position information of the SBAS satellite 12 (step S24). Note that the position of the SBAS satellite 12 can be processed to some extent within the limited calculation time of the user receiver 110, for example, position / error, position / error change rate, position / error change rate, It can also be divided into reference times. The reinforcement message creation unit 48 transmits the reinforcement message D4 to the SBAS satellite 12 (step S25). The reinforcement message D4 is transmitted from the SBAS satellite 12 to the user receiver 110.

  As described above, each of the monitoring stations 16-1 to 16-n according to the second embodiment includes the detection unit 24 that detects its own position, so that the control station 18 includes each of the monitoring stations 16-1 to 16-16. Even if the position of -n changes, those positions can be grasped. Therefore, the positions of the monitoring stations 16-1 to 16-n do not need to be fixed, and can be installed on a moving object on the sea where the position of a ship, a buoy or the like is difficult to determine.

  Since each monitoring station 16-1 to 16-n can be installed on the sea, an environment surrounded by a plurality of monitoring stations can be constructed even in the coastal area. It becomes possible to provide highly accurate reinforcement information.

  In the second embodiment described above, when the monitoring unit receives the SBAS satellite signal D2 from the SBAS satellite 12, the detection unit 24 records the detected position information when the detection unit 24 detects the position of the monitoring station. Therefore, the position recording unit 26 is not always necessary.

  In addition, the offshore object on which the monitoring station can be mounted and whose position is difficult to be determined is not limited to a ship or a buoy, and may be, for example, an offshore base for mining oil or natural gas.

  The embodiment described above can be controlled and operated by a computer circuit (for example, a CPU (Central Processing Unit)) (not shown) based on a control program. In such a case, these control programs are stored in, for example, a storage medium (for example, a ROM (Read Only Memory) or a hard disk) or an external storage medium (for example, a removable medium or a removable disk). And read and executed by the computer circuit.

10 Wide area reinforcement system (SBAS)
DESCRIPTION OF SYMBOLS 12 SBAS satellite 14 Ground system 16-1 to 16-n Monitoring station 18 Control station 20 Receiving part 22 Reference frequency oscillator 24 Detection part 26 Position recording part 28 Data processing part 30 Data transmission part 40 Data receiving part 42 Monitoring station position recording Unit 44 Satellite position calculation unit 46 Pseudo-range error calculation unit 48 Reinforcement message creation unit 100 GPS satellite 110 User receiver 200 Monitoring station 202 Detection unit 204 Transmission unit

Claims (9)

A monitoring station for a wide-area reinforcement system,
Detecting means for detecting the position of the monitoring station and outputting it as position information;
Transmitting means for transmitting the input position information;
A monitoring station comprising:   2. The monitoring station according to claim 1, wherein when the self-monitoring station receives a satellite signal from a wide-area reinforcement satellite, the detecting means detects the position of the self-monitoring station.   The position information continuously detected at a predetermined cycle by the detecting means is recorded, and when the own monitoring station receives a satellite signal from the wide-area reinforcement satellite, at least the position information recorded most recently is read and read. The monitoring station according to claim 1, further comprising recording means for outputting position information to the transmission means.   The monitoring station according to claim 3, wherein the period is set to a period shorter than a reception period of the satellite signal.   The monitoring station according to claim 1, wherein the detection unit detects an absolute position of the own monitoring station.   The monitoring station according to claim 1, wherein the detection unit detects a relative position of the own monitoring station. A control method for a monitoring station of a wide area reinforcement system,
Detect the position of the own monitoring station,
A control method characterized by transmitting the detected position as position information. Wide-area reinforcement satellite,
A monitoring station for receiving at least the signal of the wide-area augmentation satellite;
With
The monitoring station is
A wide-area reinforcement system, which is the monitoring station according to any one of claims 1 to 6. A control program for a monitoring station for a wide area reinforcement system,
Processing to detect the position of the own monitoring station;
A control program for causing a computer of the monitoring station to execute a process of transmitting the detected position as position information.

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