JPH0579849A - Avm system - Google Patents

Abstract

PURPOSE:To know a current position of a mobile station in point unit in any place by connecting a geomagnetic sensor, a gyro, a speed sensor and a GPS receiver to a location processing part to determine the position of the mobile station from information of these parts. CONSTITUTION:A location processing unit 11 comprises an AVM processing unit 12, a location processing part 13 and a GPS receiver 14. Information from a geomagnetic sensor 23, a gyro 24 and a speed sensor 25 is input to the processing part 13, while electric waves from a GPS satellite are input to the processing part 13 via the receiver 14. Position of a mobile station is determined in the processing part 13 based on this information. This position information is transmitted via the unit 12 from a data wave radio 26 to a base station together with vehicle activity information from an AVM controller 31. The base station receives this information with a radio 41 and displays it on a display of a work station 43, so that a current position of the mobile station can be known at any place thereby permitting efficient vehicle dispatching.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to an AVM system,
More particularly, it relates to an AVM system involved in mobile station location determination.

[0002]

2. Description of the Related Art As a conventional technique for detecting the current position of a mobile station such as a taxi,
There are a distributed transmission system by a sign post and a distributed reception system by a distributed reception station. The distributed transmission method is a method in which the mobile station receives the position information transmitted from the sign post to determine the current position of the mobile station.On the contrary, the distributed reception method reverses the radio waves transmitted from the mobile station. This is a method for grasping the current position of the mobile station by receiving the information at.
Radio waves of a certain frequency common to all over the country are transmitted from the sign posts, and about 100 sign posts are currently installed in the urban area of Tokyo, for example. On the other hand, the distributed receiving station is private, unlike the sign post, and there is no unified agreement for use, and it is left to the management of the base stations of each company.

There are various problems in grasping the current position of the mobile station by the above method. In the case of the distributed transmission method, the number of sign posts that can be installed is limited, and the area that can be covered by one sign post is 500 m to 1,000 m square, so the positions of mobile stations outside the coverage area cannot be determined. There is a drawback. Moreover, even if the current position of the mobile station can be grasped by the sign post, the accuracy of grasping only means that the mobile station is located within the cover area of the sign post, that is, grasping in cover area units, It was impossible to determine the specific position of the mobile station within the coverage area on a point-by-point basis.

Further, in the case of the distributed receiving station in the distributed receiving system, since the receiving sensitivity of the distributed receiving station is kept low, there is a problem that the cover area of the distributed receiving station is considerably narrower than the cover area of the sign post. It was In any case, the position determination of the mobile station by the above-mentioned conventional method is effective for each cover area, and if it goes out of the cover area, the base station cannot grasp the current position of the mobile station.

As described above, in the above system, the current position of the mobile station can be grasped only in units of the coverage area. However, some luxury passenger cars and the like are now equipped with a location technology for determining the current position of the own vehicle in units of points. A navigation system has been introduced. GPS (Global Positioning
System) and vehicle navigation using dead reckoning.
GPS is a system that performs positioning by receiving the radio waves emitted by multiple (3 or more) navigation satellites that orbit the earth. Dead reckoning calculates the trajectory of the vehicle by accumulating information from geomagnetic sensors, gyros, and vehicle speed sensors. Is the way to get.

However, GPS has a drawback that it cannot be used in the shade of a building, underground, tunnel, etc., and dead-reckoning is a method of obtaining the trajectory of a vehicle, so that it has a drawback that an absolute position must be set as an initial value. ..

As described above, the distributed transmission method / distributed reception method, which is the method for determining the current position of the mobile station, has a problem that the position of the mobile station can be determined only in units of the coverage area. Therefore, the current position of the vehicle is determined. G introduced as a technology to
PS and dead reckoning also have the above-mentioned drawbacks, respectively, and it was not possible to determine the vehicle position point by point at any place.

The present invention has been made in view of the above problems, and introduces GPS and dead reckoning navigation as a mobile station position determination method in order to refine the accuracy of mobile station current position determination from a coverage area unit to a point unit. And to provide an AVM system capable of overcoming the above-mentioned drawbacks of GPS or dead reckoning by properly combining GPS and dead reckoning, and grasping the current position of a mobile station in units of points at any place. It is an object.

[0009]

In order to achieve the above object, an AVM system according to the present invention comprises a location processing unit and an AVM (Automatic Vehicle Monitoring) operator, and the location processing unit has a GPS ( A global positioning system) receiver, a location processing unit, and an AVM processing unit are built in. Information from GPS satellites is input to the GPS receiver, while a geomagnetic sensor, a gyro, and a vehicle speed sensor are input to the location processing unit. And the GPS receiver is connected, and the position of the mobile station is determined by information from these sensors and GPS satellites.

[0010]

According to the above configuration, the location processing unit and the AVM (automatic vehicle monitoring) operation device are provided, and the location processing unit includes a GPS (Global Positioning System) receiver, a location processing unit, and an AVM processing. A unit is built in, and information from GPS satellites is input to the GPS receiver, while a geomagnetic sensor, a gyro, a vehicle speed sensor, and the GPS receiver are connected to the location processing unit. Since the position of the mobile station is determined by the information of
By receiving the radio waves from the GPS satellites, the absolute position of the mobile station is grasped, and when the radio waves from the GPS satellites cannot be received, the information from the geomagnetic sensor, gyro, and vehicle speed sensor is supplemented to determine the current position of the mobile station. It is always fixed in points.

[0011]

Embodiments of the AVM system according to the present invention will be described below with reference to the drawings. FIG. 1 is an AVM according to an embodiment.
It is the block diagram which showed the system roughly, (a) figure has shown the constitution of the mobile station, (b) figure has shown the constitution of the base station.

In FIG. 1A, the mobile station is roughly divided into an antenna / sensor unit 21, a location processing unit 11, and an AVM operator 31. The antenna / sensor unit 21 includes an antenna 22, a geomagnetic sensor 23, and a gyro 24. The location processing unit 11 includes an AVM processing unit 12, a location processing unit 13, and a GPS receiver 14.
A call wave radio 32 is connected to the operation unit 31.
The location processing unit 11 is connected to the vehicle speed sensor 25, each sensor / antenna in the antenna / sensor unit 21 and the AVM operator 31, and the data wave radio 2
6 is also connected.

Information from the geomagnetic sensor 23, the gyro 24, and the vehicle speed sensor 25 is input to the location processing unit 13, and the radio waves from the GPS satellites are passed through the antenna 22 to the GP.
It is input to the S receiver 14. These vehicle sensors and GP
The location processing unit 13 determines the position of the mobile station based on the information from the S satellite. The determined position information is transmitted through the AVM processing unit 12 together with the information indicating the activity status of the vehicle (information necessary for dispatch such as destination, arrival and waiting time) input from the AVM operator 31 via the AVM processing unit 12. From the machine 26 to the base station.

FIG. 1B shows the structure of the base station,
Reference numeral 1 is a wireless device, 42 is a wireless modem device, and 43 is a workstation. The (position) information sent from the data wave radio 26 is received by the radio 41, converted into a computer signal by the radio modem device 42, and displayed on the display of the workstation 43. On the contrary, an instruction to dispatch a vehicle from the base station to the mobile station is converted from a computer signal to a wireless signal by the wireless modem device 42 and transmitted from the wireless device 41 to the mobile station. Vehicle dispatch information and the like from the base station to the mobile station is received by the call wave radio 32 and displayed on the display of the AVM operator 31.

As described above, since the current position of the mobile station is determined by the location processing unit 11 and automatically transmitted to the base station, the base station accurately grasps the current position of the mobile station at any place. be able to. In addition A
Since the information necessary for vehicle allocation is appropriately input from the VM operation device 31, the base station can efficiently perform vehicle allocation.

FIG. 2 is a schematic diagram showing a method of position determination in the location processing unit 13. When three or more GPS satellites are available, the location processing unit 13 calculates the absolute position (latitude, longitude) based on the position information from the GPS satellites received by the GPS receiver 14 through the GPS antenna 22. , The current position of the mobile station is determined. The absolute position is calculated by the following procedure. The instantaneous position of each satellite and the distance between each satellite and the mobile station are calculated based on the orbit information and accurate time information of each satellite transmitted from the GPS satellites. Then, a circle centered on each satellite is drawn with the calculated distance between each satellite and the mobile station as a radius. The absolute position of the mobile station is determined by calculating the intersection of the drawn circles in terms of longitude and latitude.

When the GPS satellite cannot be used in the shade of the building, underground, tunnel, etc., the current position of the mobile station is calculated by dead reckoning based on the information of the vehicle sensor. Information on the absolute direction from the geomagnetic sensor 23, the relative direction from the gyro 24, and the traveling distance from the vehicle speed sensor 25 is obtained by the location processing unit 1.
3 is input, and information from each sensor is accumulated and calculated at regular intervals. The current position of the mobile station is determined by combining the cumulatively calculated result and the absolute position immediately before the GPS satellite becomes unusable.

FIG. 3 shows a position determining method by a combination of a satellite positioning system using GPS satellites and dead reckoning using vehicle sensors.

In FIG. 3, point A is the absolute position, that is, the starting point obtained by GPS, and point B is the current position of the mobile station, that is, the current position obtained by dead reckoning. In the figure, the solid line arrow indicates the running locus of the vehicle calculated from the geomagnetic sensor, the gyro, and the vehicle speed sensor, and the dotted line indicates the method of calculating the running locus. Geomagnetic sensor, gyro (angular velocity sensor)
Based on the traveling direction of the vehicle obtained from the vehicle speed sensor, the traveling distance of the vehicle obtained from the vehicle speed sensor is integrated at regular time intervals to determine the current position B.

If the GPS satellite can be received again at the point B, if the absolute position is calculated by GPS and there is a deviation from the position of the point B calculated by the dead reckoning navigation. , Point B is corrected to the absolute position.

In the above described embodiment, the GP
The absolute position can be determined by using the S satellite, and even if the GPS satellite signal cannot be received, the current position can be determined by dead reckoning based on the information from the vehicle sensor. Since the position information of the mobile station thus acquired is automatically transmitted to the base station through the AVM processing unit, the base station can acquire the current position of the mobile station at any point by points.

[0022]

As described above in detail, the AVM according to the present invention
In the system, the location processing unit and A
The location processing unit is equipped with a VM (Automatic Vehicle Monitoring) operating device, etc.
(Global Positioning System) Built-in receiver, location processing unit and AVM processing unit,
Information from GPS satellites is input to the GPS receiver, while a geomagnetic sensor, a gyro, a vehicle speed sensor, and the GPS receiver are connected to the location processing unit,
Since the position of the mobile station is determined based on the information from these sensors and GPS satellites, the base station can grasp the current position of the mobile station by points at any place within the wireless area. it can.

[Brief description of drawings]

1 shows an embodiment of an AVM system according to the present invention, (a) is a schematic diagram showing a configuration of a mobile station, and (b) is a schematic diagram showing a configuration of a base station.

FIG. 2 is a schematic diagram showing the periphery of a location processing unit for explaining a method for determining a current position of a mobile station.

FIG. 3 is a diagram showing a method of determining the position of a mobile station when radio waves from GPS satellites cannot be received.

[Explanation of symbols]

 11 Location Processing Unit 12 AVM Processing Unit 13 Location Processing Unit 14 GPS Receiver 23 Geomagnetic Sensor 24 Gyro 25 Vehicle Speed Sensor 31 AVM Operator

Claims (1)

[Claims] 1. A location processing unit and an AVM
A (automatic vehicle monitoring) operating device is provided, and the location processing unit includes a GPS (Global Positioning System) receiver, a location processing unit and an AVM processing unit, and the GPS receiver receives a GPS satellite from a GPS satellite. While the location processing unit is connected with a geomagnetic sensor, a gyro, a vehicle speed sensor and the GPS receiver, the position of the mobile station is determined by the information from these sensors and GPS satellites. AVM system that is being used.