JP2003302456A - Positioning device and gps positioning method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a positioning device and a GPS positioning method capable of always detecting the present position of a vehicle accurately and efficiently, and receiving precisely traffic information by VICS (vehicle information and communication system) information. <P>SOLUTION: A navigation device 1 detects the present position of a vehicle based on GPS information received from a plurality of GPS satellites, and corrects the present position based on DGPS (differential GPS) correction information received through a portable terminal 19. In this case, the navigation device 1 receives the DGPS correction information at longer intervals than prescribed intervals for receiving the GPS information from the GPS satellites. Namely, the number of times of acquiring the DGPS correction information is adjusted smaller than the number of times of acquiring the GPS information, and it is determined whether the present position detected by the GPS information is deviated from a road on a map or not, and when the present position is deviated from the map information road, the DGPS correction information is received separately from the case of receiving at each prescribed interval to correct the present position. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a GPS (Global Po
sitioning System: global positioning system) and a GPS positioning method.

[0002]

2. Description of the Related Art Recently, navigation devices and the like are equipped with a GPS (Global Positioning System) receiver, and by receiving radio waves from a plurality of GPS satellites, the position and altitude of a vehicle can be known. Usually GP
The calculation of the current position by the S satellite has an error of about 100 m. This is because noise is intentionally mixed in the radio waves from GPS satellites provided by the US Department of Defense for the purpose of security, and the radio waves of FM broadcasts transmitted by base stations whose exact positions are known are transmitted. DGPS (DGPS (DGPS)
The technology called ifferential GPS) is widespread.

A conventional method of detecting the current position by the DGPS will be described with reference to FIGS. FIG. 5 is a conceptual diagram showing the relationship between GPS satellites and DGPS base stations.
A vehicle equipped with an antenna receives GPS information from multiple GPS satellites launched into low earth orbit,
The DGPS correction information is received from the DGPS base station installed on the earth via the FM receiver. In addition, FIG.
It is a figure which shows the example of a display screen in which the present position of the vehicle was corrected and displayed by DGPS correction information, and a present position is corrected by collating with actual map information.

Here, D transmitted from the DGPS base station
Since the GPS correction information is received by using the FM receiver, when the VICS information similarly received by the FM receiver is received, the control unit of the navigation device switches the reception channel every predetermined time. Then, the DGPS correction information and the VICS information are received. FIG. 7 is a diagram showing a timing chart when the DGPS correction information and the VICS information are received by one FM receiver. As shown in FIG. 7, the FM receiver normally changes the reception channel to DG every 5 seconds.
Switch to PS channel, DGPS within about 40ms
Receive correction information.

With reference to FIG. 8, description will be given of a current position correction process executed in a conventional navigation device. As shown in FIG. 8, the control unit of the navigation device determines whether or not it is the reception timing of the DGPS correction information at every predetermined time (for example, every 5 seconds) (step S1).
01), when it is the reception timing of the DGPS correction information (step S101; YES), the channel of the FM receiver is switched to the DGPS channel (step S10).
2) Receive DGPS correction information (step S10)
3).

Next, the control unit switches the channel of the FM receiver to the VICS channel and receives the VICS information (step S104). Then, the control unit uses the GPS
The current position of the vehicle is detected based on the GPS information received by the receiver, and it is determined whether the detected current position deviates from the map information (step S105). Then, when the current position of the vehicle has deviated from the map information (step S105; YES), the current position of the vehicle is corrected based on the received DGPS correction information, and the corrected current position is displayed on the display screen. (Step S1
06).

[0007]

However, in such a conventional method of detecting the current position using DGPS, one FM receiver switches between the VICS channel and the DGPS channel to obtain the respective information. In many cases, a lack of data may occur in a part of the VICS information having a large data capacity during switching, because the VICS information is received. Also, when the vehicle is traveling in a place away from the FM broadcasting station such as in a mountainous area or underground, or in a section where the reception condition of the FM radio wave is poor, the DGPS correction information by the FM radio wave cannot be received or a considerable time is required for the reception. There was a problem that it would end up.

Further, depending on the reception environment of FM radio waves, if the timing is missed when the DGPS channel is switched to the VICS channel in a place where FM radio waves are difficult to receive, VICS information cannot be synchronized with the VICS channel. There is also the problem of not being able to receive. In addition, when the channel is switched every predetermined time to acquire the DGPS information,
If the interval of the reception timing of the DGPS information is too narrow, there is a problem that the processing speed of the navigation device is reduced.

An object of the present invention is to detect the current position of the vehicle with high accuracy and efficiency, and to accurately receive the traffic information based on the VICS information.
It is to provide a positioning method.

[0010]

In order to solve the above-mentioned problems, the present invention stores GPS information receiving means for receiving GPS information transmitted from GPS satellites at predetermined intervals, and map information including road information. Means for storing map information, and the above-mentioned G
A positioning device comprising: a current position detection unit that detects a first current position based on the GPS information received by the PS information reception unit and the map information acquired from the map information storage unit, The present position detecting means is further provided with a wireless communication means for receiving correction information for correcting an error included in the GPS information via a wireless communication network at an interval wider than a predetermined interval for receiving the GPS information. Is characterized in that the first current position is corrected based on the correction information received by the wireless communication means, and the second current position is detected.

Further, in the present invention, the current position detecting means is based on the GPS information and the map information, and the detected first current position deviates from a road on the map by a predetermined range or more. In this case, the wireless communication means is controlled to receive the correction information, the first current position is corrected based on the received correction information, and the second current position is detected.

Further, according to the present invention, the wireless communication means has a wireless communication function capable of accessing the Internet, and receives the correction information via the Internet.

Further, in the present invention, the radio communication means selects a radio base station closest to the radio base station constituting the radio communication network and performs radio communication with the radio base station. Is performed to receive the correction information.

Further, in the present invention, the wireless communication means selects a preset wireless base station from a plurality of wireless base stations forming the wireless communication network and performs wireless communication with the wireless base station. The correction information is received by performing the operation.

Further, according to the present invention, a step of receiving GPS information transmitted from a GPS satellite at predetermined intervals, a step of storing map information including road information, and the received G information.
First based on the PS information and the stored map information
Detecting the current position of the GPS information, the correction information for correcting an error included in the GPS information is wirelessly transmitted at an interval wider than a predetermined interval at which the GPS information is received. Receiving via a communication network, correcting the first current position based on the correction information received via the wireless communication network, and
And a step of detecting the current position of the.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described in detail below with reference to the drawings. However, the scope of the invention is not limited to the illustrated example. In the following, a case where the positioning device of the present invention is applied to a navigation device will be described as an example.

First, the structure will be described. FIG. 1 is a block diagram showing a main configuration of a navigation device 1 according to the present embodiment. In FIG. 1, the navigation device 1 includes a control unit 11, a dead reckoning unit 12, a GPS receiver 13, a storage device 14, an input device 15, and a display device 1.
6, an FM receiver 17, a mobile terminal 19 connected to the I / F unit 18, and the like, and each unit except the mobile terminal 19 is connected by a bus.

The control unit 11 reads out and executes various system programs stored in the storage device 14 to drive and control each unit of the navigation device 1. Also, the dead reckoning unit 12, the GPS receiver 13, the input device 15, and the F
According to the information input from the M receiver 17, the mobile terminal 19, and the like, various application programs for navigation stored in the storage device 14 are read out, various processing such as GPS correction processing and route search processing is executed, and various processing is performed. The result is displayed on the display device 16. The control unit 11
Has a function as the present position detecting means of the present invention.

The dead reckoning unit 12 comprises an angle sensor, a distance sensor and the like. The angle sensor detects the angular velocity of the vehicle (the angle of rotation in the horizontal direction per unit time) and calculates the amount of change in the moving direction. The distance sensor detects the pulse signal output according to the rotation of the wheel and calculates the amount of movement of the vehicle. The dead reckoning unit 13 calculates a relative position change of the vehicle based on the angular velocity signal and the vehicle speed pulse signal and outputs the change to the control unit 11.

The GPS receiver 13 is equipped with a GPS antenna (not shown) and has a plurality of Gs launched into a low earth orbit.
The GPS information transmitted from the PS satellite is received. This G
The PS antenna receives GPS information transmitted from at least four GPS satellites, outputs the received GPS information to the control unit 11, and based on this GPS information, the absolute current position of the vehicle (latitude, longitude, Altitude) is detected. The GPS receiver 13 has a function as GPS information receiving means of the present invention.

The storage device 14 is provided with a recording medium (not shown) in which programs, data, etc. are stored in advance, and various applications of the navigation device 1 executed by the control unit 11 and these are stored in the recording medium. The data and the like relating to the program are stored. For example, the recording medium stores various programs such as GPS correction processing and route search processing for performing the above-described processing, a route searched in the past, and setting data in which various setting contents regarding the operation of the navigation device 1 are recorded. Remembered.

Further, the storage device 14 is provided with a map information database (not shown) including road information, and the map information database stores road information as road information (for example, road name, national road, prefectural road, Toll road, or
One-way roads, etc., road connections (eg, three-way roads, cross roads, T-shaped roads, etc.) are stored. Further, the map information database stores map data used for detection of the current position of the vehicle, map matching, navigation display, and various symbol data of roads, facilities, the sea, lakes, and the like. That is, the storage device 14 has a function as the map information storage means of the present invention.

The input device 15 includes character keys, numeral keys, search keys, and various keys associated with various functions such as navigation, and outputs an operation signal to the operated key to the control unit 11. In addition, the input device 15
A configuration including a pointing device such as a touch panel, an input device such as a remote controller, or a configuration capable of voice input may be adopted.

The display device 16 is composed of a color liquid crystal display or the like, and in accordance with a display instruction from the control unit 11, the contents input by the input unit 15, image data such as navigation display information input from the control unit 11 and characters. Display the data.

The FM receiver 17 includes an FM antenna (not shown) and an FM demodulator for demodulating an FM radio wave received via the FM antenna. The frequency of each channel is adjusted by the control of the control unit 11 to obtain VICS information and the like. Receives various information of.

The I / F unit 18 is an interface for connecting the navigation device 1 and the portable terminal 19, and has a modulation / demodulation function for converting a digital signal and an analog signal.

The mobile terminal 19 is, for example, a mobile phone or a PH.
S, or a mobile information terminal with a built-in communication function,
A wireless communication line is established with a wireless base station to send and receive wireless signals. Specifically, the mobile terminal 19 includes the control unit 1
According to the instruction 1, the wireless base station closest to the current position is searched, and the DGPS correction information is transmitted / received to / from the wireless base station. In addition, the mobile terminal 19 uses the wireless base station to
By connecting to a network such as a LAN or WAN, the DGPS correction information is received via the Internet. That is, the mobile terminal 19 has a function as a wireless communication unit in the present invention.

Next, the operation of this embodiment will be described. A program for realizing each function described in the flowchart of FIG. 2 shown below is stored in the storage device 14 in the form of a readable program code, and the control unit 11 uses the program code. Followed actions are executed sequentially. Also, not shown CD-ROM, DV
It is also possible to execute the operation peculiar to this embodiment by using a program / data externally supplied from the D-ROM control unit or the like.

Hereinafter, the control unit 11 of the navigation device 1
The GPS correction processing executed by will be described. FIG. 2 is a flowchart showing the GPS correction processing executed by the control unit 11.

As shown in FIG. 2, the control unit 11 controls the GPS
The estimated position on the two-dimensional coordinates is detected based on the absolute position information of the vehicle acquired from the receiver 13 and the relative position change acquired from the dead reckoning unit 12. Next, the control unit 11 reads out the map information from the storage device 14, performs map matching based on the detected estimated position of the own vehicle and the detected map information, and the estimated position is not separated from the road on the map. It is determined (step S1).

Here, when the estimated position is not separated from the road on the map (step S1; YES), the control unit 11 determines whether or not it is a predetermined timing for receiving the DGPS information ( Step S2). Where DGP
If it is not the time to receive the S information, the control unit 11
Causes the display device 16 to display the estimated position estimated based on the position information obtained based on the GPS information as the current position of the vehicle, and ends the GPS correction processing. On the other hand, DGPS
If it is time to receive information (step S2;
YES), the control unit 11 controls the mobile terminal 19 to search for the wireless base station closest to the own vehicle, and receives the DGPS correction information from the wireless base station (step S4).

Subsequently, the control unit 11 receives the received DGPS.
An accurate current position of the vehicle is calculated based on the correction information (step S5), and a difference between the estimated position of the vehicle obtained in step S1 and the accurate current position of the vehicle obtained in step S5 is predetermined. It is determined whether or not it is within the range (step S
6). Here, when the difference between the estimated position of the own vehicle and the current position is equal to or larger than the predetermined range, the control unit 11 determines in step S1.
It is determined that the estimated position calculated in 1 contains an error, and the corrected accurate current position of the own vehicle is displayed on the display device 16 as the own vehicle position (step S7), and this GPS correction processing ends.

Further, returning to step S1, if the estimated position of the own vehicle is separated from the road on the map (step S1; NO), the control section 11 controls the portable terminal 19 to make the own terminal. The wireless base station closest to the vehicle is selected, the selected wireless base station is accessed to receive the DGPS correction information (step S8). Then, the control unit 11 calculates an accurate current position of the own vehicle based on the received DGPS correction information (step S9), and causes the display device 16 to display the calculated accurate current position as the own vehicle position (step S9). S
7) Then, this GPS correction process is ended.

Next, the reception timing of the DGPS information in this embodiment will be described with reference to FIGS. FIG. 3 is a timing chart showing communication timing between the mobile terminal 19 and the wireless base station. As shown in FIG. 3, the mobile terminal 19 is controlled by the control unit 11 to access the radio base station at predetermined intervals (for example, 5 seconds <time T) to receive the GDPS correction information and to perform the GPS correction. In the processing, when it is determined that the estimated position calculated based on the GPS information is separated from the road on the map, the wireless base station is accessed and the DGPS correction information is received.

Therefore, as shown in FIG. 4A, when the current position is calculated based on the conventional GPS information, F
Since the M receiver is used to receive the DGPS information at the same timing as the timing of receiving the GPS information, the calculated current position is corrected every time. On the other hand, as shown in FIG. 4B, according to the present embodiment,
If the estimated position calculated based on the GPS information is not separated from the road on the map, the estimated position calculated based on the GPS information is displayed as the current position of the vehicle, and the current position is corrected. Do not perform, D at every predetermined timing
The GPS correction information is received and the current position is corrected.

As a result, the processing steps involved in calculating the current position can be significantly reduced, the processing speed in the control unit 11 can be improved, and the communication cost involved in receiving the DGPS correction information can be reduced. .

As described above, according to this embodiment, the current position of the vehicle is detected based on the GPS information received from a plurality of GPS satellites, and the DGPS correction information received via the portable terminal 19 is used. By correcting the detected current position, the current position of the vehicle is calculated with high accuracy, and the vehicle position is provided.

Therefore, D for correcting the current position
By receiving the GPS correction information via the mobile terminal 19, the FM receiver 17 can receive only the VICS information without switching the channel. As a result, it is possible to quickly and surely acquire the VICS information and the DGPS correction information by preventing the lack of data and the decrease in the communication speed due to the switching between the VICS channel and the DGPS channel at every predetermined time. .

Further, the navigation device 1 receives the DGPS correction information at an interval longer than a predetermined interval for receiving GPS information from GPS satellites. That is, the number of times the DGPS correction information is acquired is less than the number of times the GPS information is acquired, and it is determined whether or not the current position detected by the GPS information is separated from the road on the map. If you are away from, because the DGPS correction information is received separately from the case where it is received at predetermined intervals,
It is possible to accurately detect the current position according to the detection status of the current position. Further, by receiving the DGPS correction information at a relatively slow timing, it is possible to reduce the communication cost related to receiving the DGPS correction information and improve the processing speed related to the detection of the current position.

When receiving the DGPS correction information, the mobile terminal 19 selects the radio base station closest to the current position where the vehicle is currently traveling and connects to this radio base station to connect the DGPS correction information. As a result, the communication cost can be reduced and the communication speed can be improved. Alternatively, the DGPS correction information can be reliably received even in an area where the FM radio wave is weak, and the accurate current position of the vehicle can be grasped no matter where it is.

The above description in the present embodiment is an example of the preferred navigation device 1 according to the present invention, and the present invention is not limited to this. For example, in the present embodiment, the mobile terminal 19 is configured to receive the DGPS correction information by selecting the radio base station closest to the current position and connecting to this radio base station. A configuration may be adopted in which a radio base station is always selected and DGPS correction information is transmitted / received to / from the radio base station. As a result, for example, when the nearest wireless base station is changed while the vehicle is moving, the communication status of wireless communication is deteriorated, and it is possible to prevent disconnection of communication, lack of data, and decrease in communication speed.

Further, the portable terminal 19 which receives the GDPS correction information receives the infrared rays and the microwaves from the optical beacons and the radio wave beacons installed on the road, and thereby the DGs are received.
The PS correction information may be acquired. Alternatively,
Normally, the DGPS correction information is received via the FM receiver 17, and the mobile terminal 19 is received in an area where FM radio waves are weak.
The configuration may be such that the DGPS correction information is received via the.

Furthermore, the nearest wireless base station is searched for via the mobile terminal 19, the distance from the mobile terminal 19 to the wireless base station is calculated, and the current position of the vehicle is calculated based on the calculated distance. It may be configured to correct. In addition, the detailed configuration and the detailed operation of the components of the navigation device 1 according to the present embodiment can be appropriately modified without departing from the spirit of the present invention.

[0044]

According to the present invention, by receiving the correction information for detecting the current position with high accuracy by the wireless communication means, various information other than the correction information can be efficiently obtained and the GPS information and the GPS information can be obtained. Since the correction information is received at a slower timing than the comparison, it is possible to accurately detect the current position while reducing the communication cost involved in receiving the correction information and improving the processing speed for detecting the current position. it can.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of a navigation device 1 according to an embodiment of the present invention.

FIG. 2 is a GPS executed by a control unit 11 shown in FIG.
It is a flowchart which shows a correction process.

FIG. 3 is a timing chart showing communication timing between the mobile terminal 19 shown in FIG. 1 and a wireless base station.

FIG. 4A is a diagram showing a timing of correcting the current position by the conventional DGPS correction information. FIG. 7B is a diagram showing a timing of correcting the current position by the DGPS correction information in the present embodiment.

FIG. 5 is a conceptual diagram showing a relationship between GPS satellites and a DGPS base station.

FIG. 6 is a diagram showing an example of a display screen on which a current position of a vehicle is corrected and displayed based on DGPS correction information.

FIG. 7 shows one FM including DGPS correction information and VICS information.
It is a figure which shows the timing chart at the time of receiving with a receiver.

FIG. 8 is a flowchart showing a current position correction process executed by a control unit of a conventional navigation device.

[Explanation of symbols]

1 Navigation device 11 Control unit 12 Dead Reckoning Unit 13 GPS receiver 14 Storage device 15 Input device 16 Display 17 FM receiver 18 I / F section 19 Mobile terminal

Continued front page    F-term (reference) 2F029 AA02 AB01 AB07 AC02 AC14                       AC16 AD01                 5H180 AA01 BB05 FF04 FF05 FF13                       FF14 FF22 FF27 FF32 FF37                 5J062 AA01 AA05 BB01 CC07 EE04                       HH05

Claims (6)

[Claims] 1. A GPS information receiving means for receiving GPS information transmitted from a GPS satellite at predetermined intervals, a map information storage means for storing map information including road information, and the GP.
A positioning device comprising: a current position detection unit that detects a first current position based on the GPS information received by the S information reception unit and the map information acquired from the map information storage unit, The present position detecting means further comprises wireless communication means for receiving correction information for correcting an error included in the GPS information via a wireless communication network at an interval wider than a predetermined interval for receiving the GPS information. Corrects the first current position based on the correction information received by the wireless communication means,
A positioning device that detects a second current position. 2. The current position detecting means, based on the GPS information and the map information, when the detected first current position has deviated from a road on the map by a predetermined range or more, 2. The wireless communication means is controlled to receive the correction information, the first current position is corrected based on the received correction information, and the second current position is detected. Positioning device. 3. The positioning device according to claim 1, wherein the wireless communication means has a wireless communication function capable of accessing the Internet, and receives the correction information via the Internet. 4. The wireless communication means selects the closest wireless base station among a plurality of wireless base stations forming the wireless communication network and performs wireless communication with the wireless base station. The positioning device according to any one of claims 1 to 3, wherein the correction information is received. 5. The wireless communication means selects a preset wireless base station from among a plurality of wireless base stations forming the wireless communication network and performs wireless communication with the wireless base station. The positioning device according to claim 1, wherein the correction information is received. 6. A step of receiving GPS information transmitted from a GPS satellite at predetermined intervals, a step of storing map information including road information, the received GPS information, and the stored map information. A step of detecting a first current position based on the above, wherein the correction information for correcting an error included in the GPS information is wider than a predetermined interval for receiving the GPS information. Receiving via a wireless communication network at intervals, and correcting a first current position based on correction information received via the wireless communication network to detect a second current position. A GPS positioning method comprising: