JP3932910B2 - Position correction information distribution system - Google Patents

Description

[0001]
[Technical field to which the invention belongs]
The present invention relates to a positioning system using positioning satellites such as GPS (Global Positioning System), GLONASS, and Galileo, and more particularly to a high-accuracy positioning system using position correction information distribution and a method of using the positioning system.
[0002]
[Prior art]
In general, a satellite positioning system is a navigation system that specifies (positions) the position of an aircraft, a ship, an automobile, and the like. Positioning is realized by receiving radio waves from positioning satellites floating in outer space. Positioning methods can be roughly divided into two types: (1) independent positioning method and (2) relative positioning method.
[0003]
In the single positioning method (1), radio waves are received from at least four positioning satellites simultaneously using a single satellite radio wave receiver, and the absolute position (latitude, longitude, high) is determined from the distance between each satellite and the receiver. Decide). As a specific positioning method, first, the distance from the receiving device to each positioning satellite is obtained by multiplying the arrival time of radio waves from each satellite by high speed. However, since the positioning satellite uses an atomic clock with very little error, the radio wave emission time is accurate, but the receiving device side uses the time signal sent from the positioning satellite to adjust the time, but the positioning satellite It does not have the accuracy of time.
[0004]
In addition, an error occurs because the radio wave is affected by the ionosphere, troposphere, multipath, etc. before reaching the receiving device. Because of these error factors, the exact distance from the receiving device to each positioning satellite is unknown. Therefore, the distance from the receiving device to each positioning satellite is generally called a pseudorange. Since there are four unknown variables including the absolute position (latitude, longitude, height) plus time, the position is determined by the observation amount of at least four positioning satellites.
[0005]
The accuracy of the single positioning has an error of several tens of meters until SA (Selectable Averabirity) is canceled in May 2000, and there is an error of several m to 5 m even at the time when SA is canceled.
[0006]
On the other hand, the relative positioning method of (2) is a method using a plurality of satellite radio wave receivers. In principle, single positioning at the same time is performed at a plurality of points, and the position information obtained at each point is subtracted. This is a method for obtaining a relative one. In this method, satellite orbit errors, which are considered as common error factors, and radio wave delay errors due to the ionosphere, troposphere, and the like are canceled out, so that it is possible to perform positioning more accurately than single positioning. The relative positioning method is: a. Differential positioning method (DGPS), b. There are two types of interference positioning methods.
[0007]
The basic principle of differential positioning of a is to calculate the difference between the absolute position measured by a receiving device in which a satellite radio wave receiving device is installed at a reference point called a reference point and the known absolute position, and use this as a correction amount to calculate the broadcast wave or Positioning accuracy is improved by providing position correction information using a communication network. In Japan, there are generally a method of providing correction information by MCA (Multi Channel Access) radio and a method of providing position correction information by FM broadcast waves, and there is also a correction information distribution method using satellite communication.
[0008]
The positioning accuracy by DGPS has an error of about 50 cm to several meters. Details of the differential positioning method are disclosed in, for example, Japanese Patent Laid-Open No. 6-342054.
[0009]
The interferometric positioning method of b is transmitted from the positioning satellite instead of determining the position by determining the distance by the time difference from the positioning satellite to the receiving device as in the single positioning method and the differential positioning method described so far. The distance between the positioning satellite and the receiving device is calculated using the phase (number of waves) of the radio wave. Other basic principles are similar to the differential positioning method, a satellite radio wave receiver is installed at a reference point called a reference point, and position correction information is generated from the absolute position measured by the receiver and known absolute coordinates, Position correction information is provided using broadcast waves and communication networks.
[0010]
The satellite radio wave receiving apparatus that has received the position correction information improves the positioning accuracy by using the reception information from the positioning satellite and the position correction information. RTK (Real Time Kinematic) positioning that can realize interference positioning in real time while moving with the static interference positioning method that achieves the most accurate positioning by averaging errors by long-time positioning. There is a method. The accuracy of each method is an error of several millimeters in the static interference positioning method and an error of several centimeters in the RTK positioning method. Details of the interference positioning method are disclosed in, for example, Japanese Patent Application Laid-Open No. 2000-304843.
[0011]
The relative positioning method described above increases the positioning accuracy by generating position correction information from positioning data obtained by a plurality of receiving devices (in addition to known absolute positions depending on the method) and canceling out common error factors. However, each method has several problems. In the case of differential positioning, since the positioning method itself is the same as that of independent positioning, it is easy to implement with less complicated processing. However, since positioning accuracy is about 50cm to several meters, precise surveying and precise navigation (for example, for pedestrians)
It is not suitable for applications that require (ITS).
[0012]
On the other hand, the static interference positioning method can achieve high-accuracy positioning with an error of several millimeters, but positioning requires several hours to several tens of hours and cannot move during that time. Is not suitable. However, the RTK positioning method, which is the same interference positioning method as the static interference positioning method, is capable of positioning with an error of several centimeters in real time, and is expected to be applied to high-precision positioning applications for mobile objects. However, the RTK method also has a problem, and in order to realize highly accurate positioning, the reference point exists in the vicinity of the positioning position, and its known absolute position needs to be determined extremely accurately. In order to achieve high-accuracy positioning, a reference point is required within a range of several kilometers, but in reality, there is not one reference point with a known absolute position with high accuracy at one location in several kilometers. .
[0013]
Therefore, in order to realize high-precision positioning in a wide area in real time, a position correction method called a virtual reference point method has been put into practical use in recent years. There are several virtual reference point methods, but the basic principle is that virtual reference points (virtual reference points) are contained within an area surrounded by a plurality of reference points (at least four or more in order to ensure redundancy). The observation amount at the virtual reference point is calculated by complementary calculation from the observation amount at the actually observed reference point.
[0014]
According to this method, the number of reference points actually required is one in several tens to 100 km, and it is possible to create the same environment as a state in which there is a reference point in the immediate vicinity of the positioning point. By using the virtual reference point method, it is possible to achieve highly accurate positioning over a wide area. Incidentally, the virtual reference point method is not necessarily applied to only the interference positioning method, but can be applied to the differential positioning method. Details of the virtual reference point method are shown, for example, in “Research Presentation on RTK-GPS Positioning—Virtual Reference Point Method etc.—Data Collection” (Japan Surveying Association).
[0015]
Next, a cellular digital mobile communication network used for mobile phones, PHS (Personal Handy Phone), etc. will be described. A digital mobile communication network in a cellular system is composed of many radio base stations. The role of the radio base station is to transmit radio waves to the mobile station and receive radio waves from the mobile station. A radio wave area where one base station can communicate with a mobile station is called a cell, and the service area is covered by a number of cells. The current cell radius is 1.5 km to several km for mobile phones, and 100 m to several 100 m for PHS. The mobile communication network allows mobile stations to perform information communication with each other or with another communication service via a radio base station.
[0016]
In addition, there are several methods for identifying the location of a mobile station using the radio characteristics of a cell and a radio base station, both for PHS and mobile phones, but the accuracy is extremely low, and it is about several tens to several hundreds of meters at best. It is.
[0017]
In current cellular phone systems, there is a communication system in which GPS is installed in base stations in order to accurately perform time synchronization between base stations and between mobile stations. At present, this GPS is mounted only for the purpose of time synchronization, and is not directly related to position positioning.
[0018]
[Problems to be solved by the invention]
As described above, the virtual reference point method enables real-time positioning in a wide area with high accuracy. However, a large amount of capital investment is required to develop a new infrastructure for distributing position correction information, which is a burden on the operator. As a result, in order to recover the capital investment, the business operator sets the position correction information distribution service fee collected from the user high. However, if a large amount of cost is incurred for the user, an increase as a user cannot be expected, and the realization of the business becomes difficult.
[0019]
Two methods of (1) broadcast type and (2) bidirectional type are considered to provide position correction information by the current virtual reference point method.
[0020]
In the broadcast type (1), position correction information can be provided over a wide area, but there is no means for communication with a mobile station, so it is difficult to collect information charges. As represented by BS broadcasting etc., means to collect monthly broadcasting fees can be considered, but the user needs not the position correction information but the accurate position information obtained as a result of the correction. In a situation where it is not always known whether the position correction information can be obtained reliably (for example, when the position is located outside the broadcast area), it is difficult to recover the cost from the user at a fixed amount. In addition, since the frequency of using the position correction information varies from person to person, the flat-rate billing method is not always desirable for the user. In the case of the broadcast type, since the area for which the position correction information to be provided is the broadcast area of one broadcasting company, it is necessary to collect reference point information in the area, analyze it, and provide it together. In addition to delays in the collection, analysis, and distribution of data, wasteful data transmission occurs throughout the system.
[0021]
On the other hand, in the case of the bidirectional type (2), since communication with the site providing the position correction information occurs many times in order to obtain the position correction information, there is a problem that the communication cost burden on the user increases. I have it. Similarly to the broadcast type (1), in the current bidirectional type position correction information distribution, since the reference point information of a wide area is collected and analyzed in one place, the data transmission is also wasted. became.
[0022]
As a problem that can be said for both methods (1) and (2), in the current method, since the reference point information is collected once in one place, the position correction information is generated and distributed. If a problem occurs in a server that collects, analyzes, and distributes point information, the service is stopped throughout the service area. If the virtual reference point method becomes common, it is conceivable that high-precision positioning is performed continuously in real time. For example, it is conceivable that automatic driving of an automobile is realized by satellite positioning and high-precision positioning by a virtual reference point method. In such a situation, if the distribution of the position correction information is stopped or the reliability of the position correction information is lowered, it may affect many lives.
[0023]
There are also some problems with the location of the reference point. In order to function as a reference point, it is necessary to create an environment that can be easily captured by the positioning satellites. When installing equipment, it is essential to secure a power source, maintain a communication network, and maintain a waste heat (air conditioning) environment. .
[0024]
According to the description of Japanese Patent Laid-Open No. 9-72951, differential positioning can be performed without accessing the center by using the base station of the mobile communication system and the control channel of the system for distributing the position correction information in the above-described differential positioning method. There is a way to achieve it. However, because this method uses a differential positioning method, positioning accuracy is low, and multiple base stations share and provide position correction information generated by reference points installed at intervals of about 100 km. The accuracy of the correction information itself is low.
[0025]
Accordingly, the object of the present invention is to provide a wireless base station such as a mobile phone with a function as an electronic reference point and a function for distributing position correction information, thereby enabling position correction information to be distributed over a wide area at low cost. The object is to provide a system and method for realizing high-precision positioning in real time, and terminals.
[0026]
[Means for Solving the Problems]
In the position correction information distribution system of the present invention, a radio base station that receives information from an artificial satellite is provided with an electronic reference point (the base station and the reference point are not limited to one unit, the same applies hereinafter). Any of the following features. That is, (1) the electronic reference point includes a position correction information generation device that generates position correction information from the received information, and a distribution device that distributes the position correction information to mobile stations in the communication network. ) An electronic reference point has a function of combining the received information and information of known latitude / longitude coordinates where the reference point is installed, and further distributes the reference point information to mobile stations in a communication network Or (3) a position correction information generating device that generates position correction information from the received information and position measurement information of the mobile station received from a mobile station in a communication network by the electronic reference point, and the mobile station And a distribution device that distributes the position correction information toward. Alternatively, in the position correction information distribution system of the present invention, (4) a wireless base station that receives information from an artificial satellite stores a positioning result of an electronic reference point for a predetermined period, and a positioning status from the positioning result Analyzing means for analyzing the error, a reporting device for reporting an abnormality to the monitoring server when an abnormality occurs in the analysis result, and a transmission means for transmitting the positioning results before and after the occurrence of the abnormality to the monitoring server. (5) a wireless base station that receives information from an artificial satellite is provided with an electronic reference point, and a monitoring server connected to the communication network is the wireless base station An analysis means for analyzing a positioning result before and after the occurrence of an abnormality of the reference point from a reference point abnormality notification sent from the network, and a function for remotely diagnosing the reference point, and solving the problem according to the diagnosis result Have function and / or Is equipped with a transmission means for notifying a maintenance worker or maintenance operator's terminal of a diagnosis result or a request for dispatch to the site, and further distributing information to mobile stations in the communication network. (6) Artificial The information received from the satellite is received by the wireless base station and distributed to the mobile stations in the communication network. The electronic reference point or the wireless base station may interfere with the distribution of the position correction information due to some failure. When other wireless base stations come and provide position correction information, (7) Receive information from artificial satellites at the wireless base station and distribute the information to mobile stations in the communication network The radio base station continuously provides position correction information using a part of the radio frequency band within the communication area of the own station, or (8) the radio base station The position of the mobile station in the area of your station In the event of an emergency situation that would be dangerous to the owner of the mobile station existing in the area of the radio base station, all mobile stations in the radio base station area It has a function to instruct to send location information, creates blame information based on the current location information of the mobile station sent from the mobile station, and forcibly displays the evacuation direction on the display device of the mobile station It is characterized by that.
[0027]
Further, in the corrected position information distribution system of the present invention, a radio base station that receives information from an artificial satellite is provided with an electronic reference point, and the electronic reference point is received from the received information and a mobile station in a communication network. A correction position information generation device that generates correction position information from position measurement information of a mobile station, and a distribution device that distributes the correction position information toward the mobile station are provided. In the present application, the position correction information is information for correcting the position, and the correction position means a corrected position.
[0028]
Further, the position correction information distribution method and the corrected position information distribution method of the present invention mean the method itself for implementing each of the present invention systems, but in addition to this, information from an artificial satellite is received by a radio base station for communication. A method for distributing information to a mobile station in a network, wherein the charge management server connected to the communication network polls the mobile station at regular intervals, and the position correction sent from the mobile station It is also within the scope of the present invention to charge each mobile station according to the frequency of use of information.
[0029]
Further, the mobile station terminal device used in the present invention is, for example, a mobile phone, and is used in each of the above-described systems and methods of the present invention, and the mobile station includes a recording unit for recording a condemned movement history and condemns it. It is desirable to have a function for displaying a movement history and a function for indicating the current traveling direction. Further, another mobile station terminal of the present invention is a mobile station terminal device that receives distribution of information from a radio base station that has received information from an artificial satellite, and includes position positioning means, position correction information receiving means, Corrected position information generating means for generating corrected position information from the measured position information and position correction information, a storage unit for storing the frequency of using the position correction information for a predetermined period, and position correction for polling from the billing management server Or a mobile station terminal device that receives distribution of information from a radio base station that has received information from an artificial satellite, comprising: a transmission means for transmitting a frequency of using information; Correction position information from the position information and the position correction information, a position correction information generation means for generating position correction information from the measured position information and reference point information, A correction position information generating means for generating; a storage section for storing a frequency of using the position correction information for a predetermined period; and a transmission means for transmitting the frequency of using the position correction information for polling from the accounting management server. It is characterized by that.
[0030]
Other features of each invention are as described in the claims.
[0031]
It is possible to solve the above-mentioned problems by using already established wireless base stations, especially mobile base stations nationwide, as a reference point. In many cases, mobile base stations are basically installed in places with a good communication environment, and due to the nature of their functions, a power source, a communication network, and a waste heat environment are in place. Also, depending on the mobile communication method, the base station may be equipped with a GPS, and can be used as a reference point without adding a GPS function to the base station later. In addition, by using a mobile base station, infrastructure development can be performed at a lower cost than infrastructure development from scratch.
[0032]
In addition, if position correction information is provided independently from each mobile base station, it is possible to reduce useless data transmission of the entire position correction information distribution system, thereby solving the problem of non-distribution, data delay, and communication cost. Connected. And each mobile base station provides position correction information in a self-sustaining manner, and even if one base station stops due to a trouble such as a failure, the entire position correction information distribution system will be affected. There is no, and high-precision positioning is possible without changing the user. Furthermore, each base station is equipped with a reference point information recording function for a predetermined period and a reference point positioning result analysis function, so that even if a problem occurs in the reference point, the problem can be quickly identified and solved. It is possible.
[0033]
The method for providing position correction information is a method in which a mobile base station uses a communication band used to specify a cell in which each mobile terminal exists, or a part of a mobile phone communication band for providing position correction information. It is possible to reduce the waste of data transmission and the communication cost by transmitting data to the mobile stations in the cell area in a broadcast type. Billing for the user is recorded for a predetermined period according to criteria such as the number of times the position is actually measured by the position correction information, time, etc., and the information is accumulated in the billing server by periodic polling from the mobile base station. It is billed together with the usage fee. For the user, not only is charged for the amount used, but the cost can be settled together with the mobile phone, so the number of settlements can be reduced from two to one.
[0034]
If a mobile base station is used as a reference point, the mobile base station is often installed in a place where the communication environment is basically good, and the power, communication network, and waste heat environment are in place due to the nature of its functions. Yes. Also, depending on the communication method, the mobile base station may be equipped with GPS, and the infrastructure can be maintained at a lower cost than when the infrastructure is maintained from scratch using the base station.
[0035]
As described above, according to the present invention, it is possible to realize a stable high-accuracy positioning system with a lower cost investment than before, and it is possible to charge a user according to use.
[0036]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings. First, FIGS. 1 to 10 illustrate a first embodiment.
[0037]
A position correction information distribution method according to the first embodiment will be described with reference to FIG. Although this embodiment uses a mobile phone network and a GPS artificial satellite as an example, it is also possible to apply a PHS or other wireless communication network instead of the mobile phone network, and the satellites used for positioning are other than GPS satellites. It can be a positioning satellite.
[0038]
The position correction information distribution system of this embodiment includes a GPS satellite 101, an electronic reference point 102 having a known absolute position, a mobile phone base station 103, a mobile station 104, a charging server 105, a monitoring server 106, and a mobile communication network 107. The position correction information is provided to the user who owns the mobile station.
[0039]
The GPS satellite 101 periodically transmits a signal from the satellite orbit to the ground. The reference point 102 installed on the ground includes a GPS receiving antenna 108, a GPS receiving unit 109 connected to the antenna 108, a control unit 110 connected to the receiving unit 109, and a GPS data process connected to the control unit 110. The GPS receiving antenna 108 receives a GPS signal, the GPS receiving unit 109 demodulates the signal, and the GPS data processing unit 111 performs a positioning operation through the control unit 110.
[0040]
The mobile base station 103 includes a communication antenna 112, a radio unit 113 connected to the antenna 112, a control unit 114 connected to the radio unit 113, a data processing unit 115 and a storage unit 116 connected to the control unit 114, The GPS positioning data sent from the reference point 102 is received by the control unit 114, and is combined with the known absolute position of the reference point recorded in the storage unit 116 by the data processing unit 115. After position correction data is generated and modulated by the wireless unit 113, position correction information is transmitted from the communication antenna 112. Here, the reference point 102 and the mobile base station 103 are integrated, but the mobile base station side knows the exact absolute position of the reference point, and the distance between the reference point 102 and the mobile base station is appropriate. If it is a short distance, it does not need to be integrated. There are a plurality of reference points 102 and base stations 103 having such a configuration.
[0041]
A mobile station (more precisely, a mobile station terminal device; the same applies hereinafter) 104 is connected to a communication antenna 118, a radio unit 119 connected to the antenna 118, a control unit 120 connected to the radio unit 119, and the control unit 120. The position correction processing unit 121, the sound processing unit 122, the storage unit 123, the operation unit 124, the display unit 125, the data processing unit 126, the GPS receiving unit 127, and the GPS receiving antenna 127 to which the GPS receiving unit 127 is connected. The position correction information distributed from a plurality of mobile base stations 103 in the vicinity of the mobile station 104 or a single mobile base station 103 is received by the communication antenna 118, and the radio unit 119 demodulates the signal, The data is stored in the storage unit 123 through the control unit 120.
[0042]
On the other hand, the GPS signal from the GPS satellite 101 is received by the GPS receiving antenna 128, the signal is demodulated by the GPS receiving unit 127, and the position is measured by the data processing unit 126 through the control unit 120.
[0043]
The positioning data calculated by the data processing unit 126, the GPS signal, and the position correction information stored in the storage unit 123 are processed by the position correction processing unit 121 to generate corrected position information. The corrected position information is displayed on the display unit 125 in the form of a character indicating a coordinate value or a position on a map. Here, the case where the position positioning function is installed in the mobile station is taken as an example, but the apparatus has an independent position positioning function, and may be connected to the mobile station by a wire such as a short-range wireless or a serial connector.
[0044]
When the mobile station 104 performs position positioning using the position correction information, the mobile station 104 uses the number of position correction information used for positioning, the number of times of positioning, positioning time, positioning accuracy, the positioning location, radio wave reception status, etc. as a usage scale, The counter information recorded in the storage unit 123 is changed. Here, the number of position correction information represents the number of correction information received by the mobile station 104 from the nearby mobile base station 103 and actually used for position correction. The number of positionings indicates how many times positioning has been performed using the position correction information. The positioning accuracy represents the accuracy of the position actually measured, and the positioning accuracy uses indices such as the supplement number of GPS satellites 101, the DoP (Dilution of Precision) value, the reception sensitivity of GPS signals, and the standard deviation of position coordinates. It can be expressed by things. When the accuracy is digitized, it can be digitized by combining any or some of these indices and used as one of the utilization scales of the position correction information. The measured location represents a location where the mobile station 104 has measured the position, and the count number of the counter can be changed depending on the reception area (here, the cover area 129 of one mobile base station). For example, a method is conceivable in which the count number of the counter is decreased in an area where position positioning is frequently used and the count number is increased in a low place.
[0045]
The reception status of radio waves has a high relationship with the count at the previous location, but it is conceivable to reduce the count number in places where the radio wave reception environment is not good and increase the count number in good locations. As the count number of the counter, any one of these is used, or some are combined to determine the count number or the unit for counting.
[0046]
The position correction information billing server 105 includes a control unit 131, a storage unit 130 connected to the control unit 131, an I / F 132, and a billing processing unit 133, and stores customer information stored in the storage unit 130. Originally, counter information stored in the storage unit 123 is transmitted from the mobile base station 103 to the mobile station 104 from the control unit 131 and the I / F 132 to the charging server using the mobile communication network 107. , Polling.
[0047]
The billing server 105 processes the counter information sent from the mobile station 104 by the billing processing unit 133, accumulates the processing results in the storage unit 130, and charges the user. In the present embodiment using the mobile communication network, this charge may be collected from the user together with the usage fee of the mobile phone.
[0048]
The monitoring server 106 includes a control unit 135, a storage unit 134 connected to the control unit 135, an I / F 136, and a monitoring processing unit 137. The monitoring server 106 includes a mobile communication network 107, an I / F 136, A position measurement abnormality notification of the reference point 102 is received from the mobile base station 103 through the control unit 135. The monitoring server 106 analyzes the cause of the abnormality by the monitoring processing unit 137 and performs recovery processing, and records the analysis result and the recovery processing result in the storage unit 134.
[0049]
Next, the concept of the data structure of the position correction information provided by the mobile base station will be described with reference to FIG. The position correction information 201 includes a header section 202 and a data body 203. The header section 202 includes a data identification code 204, a base station identification code 205, a message type 206, a status 207, and a parity 208. The data identification code 204 indicates that this data is position correction information. The base station identification code 205 indicates from which base station this data is transmitted. Message type 206 indicates what kind of data to send. Since there may be a situation where the position correction information cannot be transmitted from the base station, such as a satellite failure, a reference point failure, or a base station failure, the status 207 indicates the distribution status of the position correction information. The parity 208 is used for signal error correction. The data body 203 includes data such as satellite positioning time, reference point number, ephemeris data, almanac data, carrier wave phase, pseudorange, and positioning coordinates as reference point positioning data, as well as a known absolute position of the reference point. Reference point difference data between the data, positioning data of the reference point, and known absolute position data is stored. These data are encrypted as necessary. This data is preferably distributed based on a standard standardized as RTCM (Radio Technical Commission for Maritime) SC-104.
[0050]
With reference to FIG. 3, the flow of position measurement at the mobile station 104 will be described. In step 301 of receiving the peripheral base station information of the terminal, the mobile station 104 obtains location information of mobile base stations in the vicinity. Next, in step 302 for calculating an approximate distance to the base station closest to itself, the mobile station 104 performs position measurement without position correction, and based on the position information of the nearby mobile base station obtained in step 301. Calculate the approximate distance from the mobile station 104 to the mobile base station that is expected to be the closest. In step 303, it is determined whether or not the mobile station 104 adopts the virtual reference point method. If the mobile station 104 does not adopt the virtual reference point method in step 303, the process proceeds to step 304, where position correction information is obtained from the nearest base station calculated in step 302, and relative positioning is performed in step 305. To complete positioning. As a positioning method at this time, a differential method using an independent reference point or an RTK method can be considered.
[0051]
If the mobile station 104 adopts the virtual reference point method in step 303, the process proceeds to step 306. In step 306, it is determined whether or not the distance to the nearest mobile base station calculated in step 302 is a distance that allows highly accurate position measurement when a relative positioning method using a single reference point is used (that is, (Determining whether the nearest neighbor base station distance is greater than the threshold). If a nearby mobile base station exists at a distance where high-accuracy position positioning is possible, the process proceeds to step 304, and position positioning is performed in the procedure described above. As a result of the determination in step 306, when the relative positioning method using a single reference point is used as the distance to the nearest mobile base station, the process proceeds to step 307 if the distance is not within a range where highly accurate position positioning is possible. Each position correction information is obtained from the mobile base station group. In step 308, it is determined whether or not the number of position correction information obtained in step 307 satisfies the number and conditions necessary for generating the virtual reference point. If it is determined in step 308 that the number of position correction information does not satisfy the number or condition necessary for generating the virtual reference point, the process proceeds to step 304 and the position correction information obtained from the mobile base station closest to the mobile station 104 The position positioning is performed in the procedure after step 304 described above. If it is determined in step 308 that the number of pieces of position correction information satisfies the number and conditions necessary for generating the virtual reference point, the process proceeds to step 309 and the virtual reference point is determined using the obtained plurality of reference point information. Generate and perform positioning based on the information. As the positioning method at this time, any positioning method may be used as long as it is a method corresponding to the position correction data format obtained by the virtual reference point method.
[0052]
In step 308 described above, the conditions necessary for generating the virtual reference point are described. For example, the obtained distance between the mobile base stations is a suitable distance for generating the virtual reference point. Or the like. Usually, since a mobile station communicates with a mobile base station within a range of several kilometers to several tens of kilometers, there is no need to worry about the distance between the mobile base stations.
[0053]
In this flow, the flow is explained on the assumption that the reference point and the mobile base station are integrated, but as mentioned earlier, the mobile base station side knows the exact absolute position of the reference point. If the distance between the reference point and the mobile base station is not so far, the two do not necessarily have to be integrated. In that case, when determining the distance between the mobile station and the mobile base station, the determination may be made not by the distance from the mobile station to the mobile base station but by the distance from the mobile station to the reference point adopted by the mobile base station. .
[0054]
With reference to FIG. 4, the flow of charging by using position correction information on the mobile station side will be described. First, in step 401 for obtaining reference point data or position correction data from a base station, the mobile station 104 receives position correction information from a nearby mobile base station. In subsequent step 402, the mobile station 104 performs position positioning based on the position correction information. In the next step 403, it is determined whether or not the position has been actually measured based on the obtained position correction information. If it is determined in step 403 based on the obtained position correction information that the position positioning has actually been performed, the process proceeds to step 404 where the count of the charging counter information is increased, and the number of position correction information used for positioning, the number of positioning times, the positioning time, The billing counter information stored in the storage unit 123 of the mobile station 104 is counted up by the data processing unit 126 using the positioning accuracy, the location where it is measured, the reception status of radio waves, etc., and then the billing counter information is obtained again. Store in the storage unit 123.
[0055]
Here, the number of position correction information represents the number of position correction methods that the mobile station 104 has obtained from nearby mobile base stations and is actually used. The number of positionings indicates how many times positioning has been performed using the position correction information. The positioning accuracy represents the accuracy of the position actually measured, and the positioning accuracy can be expressed by using the supplementary number of satellites, indices such as the DoP value, reception sensitivity, and deviation. When the accuracy is digitized, it can be expressed numerically by combining any or some of these indicators.
[0056]
The measured location represents a location where the mobile station 104 has determined the position, and the count number of the charging counter information can be changed depending on the area. For example, a method is conceivable in which the count number of the billing counter information is decreased in an area where location positioning is frequently used and the count number is increased in a low place.
[0057]
The reception status of radio waves is highly related to the change in the number of counts according to the previous location, but it is possible to reduce the count number in places where the radio wave reception environment is not good and increase the count number in good places. It is done.
[0058]
The count number of the accounting counter information is determined by using any one of these or combining some of them.
[0059]
If it is determined in step 403 that the position positioning has failed due to the influence of the position correction data or the failure of the mobile station 104, the failure of the positioning function incorporated in the mobile station, etc., the process proceeds to step 405 and the accounting counter information is counted as it is. Do not up. In step 406, it is determined whether or not the positioning is to be continued. If the positioning is to be continued, the processing from step 401 described above is performed. If not continued, the positioning is terminated.
[0060]
The charging counter information stored in the storage unit 123 of the mobile station 104 is stored until there is an information upload instruction from the charging server. The memory area in which the billing count number is stored is preferably a tamper-resistant area so that the user cannot access it and cannot perform tampering from the outside.
[0061]
With reference to FIG. 5, the flow of charging by using the position correction information on the charging server side will be described. In step 501 in which each correction information contract terminal is polled, the billing server 105 polls the mobile station to increase the billing counter information. In the next step 502, a response from the mobile station (= terminal) is determined. In step 503, a transmission instruction (= transmission request) for charging counter information is transmitted to the mobile station that has responded. Step 504 determines whether or not billing counter information from the mobile station has been received. If it has been received, the process proceeds to step 505, and a clear command for clearing the charging counter information stored in the storage unit is transmitted to the mobile station that has transmitted the charging counter information.
[0062]
If charging counter information from the mobile station is not received in step 504, the process proceeds to step 506. If there is no response from the mobile station in step 502, the process proceeds to step 506. In step 506, the mobile station is polled again after a predetermined time. If there is a response from the mobile station in the next determination step 507, the process proceeds to step 503, and the processing after step 503 is performed according to the procedure described above. If there is no response from the mobile station in step 507, the process proceeds to step 508, where it is determined whether or not the charge aggregation period has passed. If the period has not passed, the process returns to step 506, and the subsequent processing is performed according to the procedure flow described above. If the deadline has passed, in step 509, the user (user) is notified using means such as e-mail that accounting counter information will be aggregated for the next aggregation period (ie, payment for the next month, for example). And exit.
[0063]
The maintenance flow of the reference point on the mobile base station side will be described with reference to FIG. In step 601 of receiving a signal from a positioning satellite, the reference point 102 receives a GPS signal from a GPS satellite. In the subsequent step (= step for comparing the known coordinate value and the positioning result) 602, the data processing unit 115 compares the position coordinate determined by the reference point with the known position coordinate stored in the storage unit 116 of the mobile base station 103. To do. In a determination step 603 for determining whether or not the comparison result satisfies a predetermined reference, it is determined whether or not the comparison result between the position coordinate measured by the reference point 102 and the known position coordinate satisfies a predetermined reference value. Yes. The reference here is the difference (distance) between the measured position coordinate and the known position coordinate, and the difference (distance) between the average value of the difference (distance) between the position coordinate measured up to that point and the known position coordinate. ), The difference (distance) from the average of the position coordinates measured up to that point, the reception sensitivity of the signal from the GPS satellite, the GoP value, and the like are considered as references. In step 603, if the comparison result between the position coordinates measured by the reference point 102 and the known position coordinates satisfies a predetermined reference value, the process proceeds to step 604, and the distribution of the position correction information is continued.
[0064]
In step 603, if the comparison result between the position coordinates measured by the reference point 102 and the known position coordinates does not satisfy the predetermined reference value, the process proceeds to step 605, and the position correction information distribution is temporarily interrupted. At this time, the distribution of the position correction information is temporarily interrupted, but the position positioning itself is continuously performed for a predetermined time and recorded as log data in the storage unit 116 of the mobile base station 103.
[0065]
In addition, the log data before and after the occurrence of the abnormality are frozen until the problem is solved and cannot be deleted. In step 606, a location notification abnormality notification is transmitted to the monitoring server 106 using the mobile communication network 107 of the mobile base station 103. In step 607, log data before and after the occurrence of an abnormality is transmitted to the monitoring server 106 using the mobile communication network 107. In step 608, the diagnosis result (check result) in the monitoring server 106 is received. In step 609, the diagnosis result from the monitoring server 106 is determined. If there is no abnormality in the diagnosis result of the monitoring server 106, the process returns to Step 601, and the processes after Step 601 are performed according to the procedure described above. If there is an abnormality in the diagnosis result of the monitoring server 106 in step 609, the process proceeds to step 610, where the positioning of the reference point 102 and the position correction information distribution by the mobile base station 103 are stopped and terminated.
[0066]
The maintenance flow of the reference point on the monitoring server side will be described with reference to FIG. In step 701 of receiving an abnormality notification from the base station, the monitoring server 106 receives a position measurement abnormality notification of the reference point 102 from the mobile base station 103. Next, in step 702 for requesting the base station to transmit log data, the monitoring server 106 requests the mobile base station 103 to transmit log data before and after the occurrence of an abnormality. In step 703, log data sent from the mobile base station 103 is analyzed by the monitoring processor 137. In step 704, it is determined whether or not there is a problem in the analysis result. If there is no problem, the process proceeds to step 705 to notify the mobile base station 103 that there is no problem and the process ends. If there is a problem in step 704, the process proceeds to step 706, where it is determined whether the problem can be identified and the problem can be solved remotely. If the problem can be solved from a remote location, the process proceeds to step 707, where the problem is solved by remote operation. After the test is performed in step 708, a position correction information distribution restart command is transmitted to the mobile base station 103. If the problem cannot be solved by remote control in step 707, a maintenance worker is requested to be dispatched to the mobile base station 103 (reference point 102) in question in step 709. At this time, if the maintenance worker has a portable terminal or the like with a built-in communication function and a position positioning function, the worker in the vicinity is instructed to move to the site and repair. When a maintenance worker does not have such a terminal, the maintenance worker is requested to be dispatched to the terminal of the service center closest to the mobile base station 103 (reference point 102) having the problem. .
[0067]
Next, the mechanism of the distributed correction information distribution service, which is one of the features of this position correction information distribution system, will be described with reference to FIG.
[0068]
The mobile station 801 receives position correction information from a plurality of mobile base stations 802 existing in the vicinity. At this time, it is assumed that the mobile base station 802a is unable to distribute the position correction information due to a reference point trouble or a mobile base station trouble. In this case, the mobile station 801 obtains position correction information from the mobile base station 802b, which is one of the neighboring base stations, instead of the mobile base station 802a, thereby securing the necessary number of position correction information.
[0069]
Next, a flow of evacuation guidance using high-precision location information and a mobile phone network when an emergency such as a disaster occurs will be described with reference to FIG.
[0070]
In step 901, the mobile base station 103 receives from the central office that an emergency has occurred in the corresponding area from the country, local government, police, fire department or the like. Next, in step 902, the mobile base station 103 receives a confirmation command for the exact position of the mobile station existing in the cover area 129 of the mobile base station 103 from the central station. In the next step 903, the mobile base station 103 transmits a current position information transmission command to all mobile stations existing in the cover area 129. In step 904, the mobile station existing within the coverage area of the mobile base station 103 receives the current position information transmission command from the mobile base station 103. In the next step 905, the mobile station that has received the current position transmission command from the mobile base station 103 forcibly transmits the current position information to the mobile base station 103. In step 906, the mobile base station 103 receives the current position information from the mobile stations existing in the cover area. In subsequent step 907, individual evacuation information is generated according to the current position of each mobile station received in step 906, and the evacuation information is transmitted to the mobile station. At this time, the generation of the evacuation information does not necessarily need to be information for each moving object. In step 908, the mobile station existing in the coverage area of the mobile base station 103 forcibly receives the evacuation information from the mobile base station 103 and forcibly displays it on the display unit of the mobile station. Since the current position of the mobile station changes constantly, evacuation information corresponding to the current position is provided in real time by repeating the above flow.
[0071]
A display screen of information sent from the mobile base station when an emergency situation requiring evacuation occurs in an area where a moving object exists will be described with reference to FIG. If the moving body is equipped with a display device capable of displaying a map, the movement locus after the occurrence of an emergency is the line 1001, the sampling point is the point 1002, and the current position and traveling direction are Displayed by the character 1003 or the like. In addition, the evacuation direction corresponding to the current position is largely displayed by a character 1004 such as an arrow and text information 1005. In order to facilitate evacuation, landmark information and direction are displayed on the map. When the moving body is equipped with a display device that cannot display a map, character information such as text information or an arrow composed of bits is displayed on the display device to provide evacuation information. Of course, the traveling direction may always be displayed above.
[0072]
Finally, a position correction method using positioning satellites such as GPS satellites will be described. The example of FIG. 11 shows an example of dispersion correction that provides position correction information from a plurality of mobile base stations 1100 with electronic reference points (= VRS generation) located around the mobile terminal 104 (= GPS and VRS installed). Yes. The example of FIG. 12 is different from FIG. 11 in that the mobile terminal 104 is equipped with a GPS and not a VRS. In this case, the mobile station (for example, the mobile terminal) 104 locates its own location. It is an example of dispersion correction in which a correction position is transmitted from one base station 1100 and received from there. FIG. 13 shows a concept in which the mobile station 104 obtains position correction information from the electronic reference point 1100 in addition to information from GPS satellites.
[0073]
FIG. 13 will be described. For positioning of the position by the positioning satellite 101, the distance between the satellite 101 and the mobile station 1103 is calculated by using a radio wave transmitted from the positioning satellite 101, and the position is specified. Due to the influence of the ionosphere, troposphere, multipath, etc., a time error is generated, so that an error is generated in the distance between the satellite 101 and the mobile station 1103, and an error also occurs in positioning (specification) of the position. In the relative positioning method, in order to reduce this error, apart from the mobile station 1103, a receiver called a reference point 1102 is installed at a point where an accurate position is already known. An error amount is calculated by comparison, and this is provided to the mobile station 1103 as correction information. When positioning the position on the mobile station 1103 side, by taking this correction amount into consideration, the error factor is canceled and a more accurate position can be determined. At this time, since the error factor changes every moment, it is necessary to always receive the correction information while measuring the position. As a means for providing correction information, a method using DMCA radio, FM broadcast wave, or medium wave beacon is generally used.
[0074]
As explained above, by using mobile base stations already established throughout the country as a reference point, it is not necessary to investigate a location that satisfies the reference point installation condition, and a position correction information distribution infrastructure is established from scratch. The infrastructure can be improved at a lower cost. In addition, the mobile base station assigns a fixed part of the communication band used to specify the cell in which each mobile terminal is located, or a part of the communication band of the mobile phone, to provide position correction information. It is possible to reduce data transmission waste and communication costs by transmitting data to a mobile station in a broadcast type.
[0075]
In addition, by providing position correction information independently from each mobile base station, it is possible to reduce unnecessary data transmission of the entire position correction information distribution system, which makes it impossible to distribute, reduce data delay, and reduce communication costs. It is. Even if one reference point (base station) stops due to a trouble such as a failure, the user can continue high-precision positioning without changing.
[0076]
In addition, each mobile base station is equipped with a reference point information recording function for a predetermined period and a reference point positioning result analysis function, so that if a problem occurs in the reference point, the problem can be quickly identified and solved. It becomes possible.
[0077]
In addition, the position correction information is recorded for a predetermined period according to the criteria such as the number of times the position is actually measured and the time, and the information is accumulated in the billing server by periodic polling from the mobile base station, and is combined with the mobile phone usage fee By charging, the user is charged for the amount used, and since the expense can be settled together with the mobile phone, the number of settlements can be reduced from two to one.
[0078]
By using the mobile phone base station as a reference point and as a position correction information distribution device, if a disaster or the like occurs, the location of the person etc. in the mobile base station communication area can be accurately determined This makes it possible to specify the appropriate evacuation guidance.
[0079]
【The invention's effect】
As described above, according to the present invention, by providing a wireless base station such as a mobile phone with a function as an electronic reference point and a function for distributing position correction information, it is possible to distribute position correction information over a wide area at low cost. It is possible to achieve high-accuracy positioning in real time.
[Brief description of the drawings]
FIG. 1 is an overall explanatory diagram of a position correction information distribution system according to an embodiment of the present invention.
FIG. 2 is an image diagram of a position correction data structure used in the embodiment of FIG.
FIG. 3 is a mobile station position positioning flowchart according to the embodiment of FIG. 1;
FIG. 4 is a mobile station charging flowchart according to the embodiment of FIG. 1;
FIG. 5 is a charging server charging flow diagram according to the embodiment of FIG. 1;
FIG. 6 is a base station (reference point) maintenance flow diagram according to the embodiment of FIG. 1;
FIG. 7 is a monitoring server maintenance flowchart according to the embodiment of FIG. 1;
FIG. 8 is an explanatory diagram of a distributed position correction information distribution system according to the embodiment of FIG. 1;
FIG. 9 is an emergency evacuation guidance flow diagram according to the embodiment of FIG. 1;
FIG. 10 is an emergency evacuation guidance display image diagram according to the embodiment of FIG. 1;
FIG. 11 is a conceptual explanatory diagram of a method example of position correction using a positioning satellite such as a GPS satellite group.
FIG. 12 is a conceptual explanatory diagram of a method example of position correction using a positioning satellite such as a GPS satellite group;
FIG. 13 is a conceptual explanatory diagram of a method example of position correction using a positioning satellite such as a GPS satellite group.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 101 ... GPS satellite, 102 ... Electronic reference point, 103 ... Base station, 104 ... Mobile station, 105 ... Billing server, 106 ... Monitoring server, 107 ... Mobile communication network, 108, 128 ... GPS receiving antenna, 109, 127 ... GPS receiving unit, 110, 114, 120, 131, 135 ... control unit, 111 ... GPS data processing unit, 112, 118 ... communication antenna, 113, 119 ... wireless unit, 115, 126 ... data processing unit, 116, 123, 130, 134 ... storage unit, 117, 132, 136 ... I / F, 121 ... position correction processing unit, 122 ... audio processing unit, 124 ... operation unit, 125 ... display unit, 129 ... cover area, 133 ... billing processing unit 137... Monitoring processing unit.

Claims (2)

A radio base station that receives information from an artificial satellite is provided with an electronic reference point, and a position correction information generation device that generates position correction information from the received information by the electronic reference point, and a mobile station in a communication network and a distribution apparatus that distributes the position correction information Te, the radio base station includes a storage unit that stores predetermined period positioning result of the electronic reference points, and analyzing means for analyzing the positioning status from the positioning result, the Distributing position correction information characterized by having a reporting device for reporting an abnormality to the monitoring server when an abnormality occurs in the analysis result, and a transmission means for transmitting the positioning results before and after the occurrence of the abnormality to the monitoring server system. 2. The position correction information distribution system according to claim 1, wherein the radio base station provides the position correction information using a part of a radio frequency band in a communication area of the own station. .

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