JPH06109827A - Position detecting apparatus - Google Patents

Abstract

PURPOSE:To always obtain high-accuracy positional data by a method wherein positional data detected by utilizing a satellite for GPS or the like is corrected with high accuracy. CONSTITUTION:A self-position (GPS positional data) is found by a self-position operation means 6 on the basis of a signal received by a GPS reception means 4. On the other hand, when a positional signal (beacon positional data) is obtained from a beacon reception means 2, the difference between the beacon positional data and the GPS positional data at this time is operated by an offset-value operation means 10. The difference is stored in a storage means 12 together with the combination of satellites. After that, the GPS positional data is corrected by a correction means 8 on the basis of the difference in the same combination of satellites out of stored differences.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a position detecting device that uses both position detection using satellites such as GPS and position detection using on-road transmitting means such as beacons, and is installed in an automobile or the like. Regarding things.

[0002]

2. Description of the Related Art In recent years, an automobile navigation system has been developed which detects the position of an own vehicle by various methods and displays the position of the own vehicle on a map by a CRT or the like, and has begun to be installed in an actual vehicle.

The position detecting method is a position detecting method using a satellite, for example, a method called GPS described in Japanese Patent Laid-Open No. 62-277573, a beacon, a sign post, etc. There is known a position detecting method utilizing the above-mentioned on-road installation transmitting means, for example, a method described in Japanese Patent Laid-Open No. 62-279499.

In the former satellite-based position detection method, a large number of satellites orbiting the earth transmit respective position detection signals, and signals from a plurality of such satellites, for example, four satellites. Are simultaneously received, and an appropriate calculation is performed based on those signals to detect the self-position. As such a position detection system, in addition to the GPS described above, for example, one called GLONAS is also known. There is.

In the latter method for detecting the position using the on-road installation transmission means, position signal transmission means called beacon or sign post is installed at an appropriate place on the road at a predetermined interval on the road, and the transmission means is used. A position signal indicating the installation location of the transmission means is transmitted, and when it comes near the installation location of each position signal transmission means, the position signal from each position signal transmission means is received and the self position is the position shown in the signal. Is to detect.

[0006]

However, each of the above methods has merits and demerits, and it is not always possible to perform satisfactory position detection by itself.

That is, in the case of using the satellite, the signal from the satellite can be received at all times in principle, and therefore the position can be detected continuously, that is, continuously while traveling, but the position detection accuracy is not necessarily high, for example, about 30 m or There is a problem that it contains more error. Further, in the case of using the on-road transmitting means, the position signal is directly received so that the position detection accuracy is extremely high, but the position cannot be detected at all times, that is, the position can be detected only at the place where the transmitting means is installed. Have a problem.

In view of the above circumstances, an object of the present invention is to provide a position detecting device capable of performing highly accurate and constant position detection.

[0009]

In order to achieve the above-mentioned object, a position detecting device according to the present invention includes: a first receiving means for receiving a position signal transmitted from a position signal transmitting means installed on a road. A second receiving means for receiving a position detecting signal transmitted from a satellite; a self position calculating means for calculating a self position based on the position detecting signal received by the second receiving means; An offset value calculation means for calculating an offset value between the self-position calculated by the self-position calculation means and the self-position obtained based on the position signal received by the first reception means, and ◆ by the offset value calculation means Storage means for storing the calculated offset value and the combination of satellites at the time of calculating the offset value, and the self-position calculated by the self-position calculating means And correcting means for correcting, based on the offset value of the combination of the same satellite and a combination of satellites during the self-position calculation of the offset value stored in 憶 means, characterized in that it comprises an.

[0010]

According to the position detecting device constructed as described above,
The second receiving means and the self-position detecting means constantly provide position data (satellite position data) based on a signal from a satellite.
Is calculated, and the self position is detected.

The first receiving means, the offset value calculating means, and the storing means also cause the position signal transmitted from the transmitting means when the position signal transmitting means installed on the road is passed (the transmitting means of the transmitting means). Position data), the own position is detected, and an offset value (difference) between the position data of the transmitting means and the satellite position data at the time of detecting the position data of the transmitting means (when passing through the installation location) is obtained.
The combination of the offset value and the satellite at the time of calculating the offset value, that is, the combination of the transmitting satellites of the signals used for calculating the satellite position data used for the offset value calculation (the transmitting satellites of the signals used for calculating the satellite position data are Which satellite of the many satellites orbiting the satellite and which satellite) are stored.

[0012] Then, by the correction means, the satellite position data is a combination of the satellites at the time of calculating the satellite position data among the stored offset values, that is, a combination of transmitting satellites of signals used for the satellite position data calculation. It is corrected using the offset value of the same satellite combination.

That is, the error of the satellite position data differs depending on the combination of satellites used for the position data calculation, but if the same combination is used, it can be considered that the error is the same to some extent, although it may fluctuate to some extent due to other factors. . Therefore, as described above, the offset value (error) of the satellite position data is detected based on the high-accuracy transmission device position data obtained when the position signal transmission device installed on the road passes through the installation location, and the offset value (error) is detected. By storing the combination data together with the combination and then correcting the satellite position data using the stored offset value of the same satellite combination, it is possible to always obtain highly accurate position data.

[0014]

Embodiments of the present invention will now be described in detail with reference to the drawings.

FIG. 1 is a block diagram showing an embodiment of the present invention. The illustrated embodiment is a position detecting device mounted on an automobile, in which a beacon is used as a position signal transmitting means installed on a road and a GPS (GLOBAL PAL) is used as a satellite.
OSITINGING SYSTEM) satellites are used.

The above-mentioned beacon is installed on the road, that is, at a position near the road, such as in the center or side of the road, and is installed at an appropriate place on the road, for example, at predetermined intervals along the road. Each beacon constantly transmits a position signal (position data itself) indicating its installation location.

The GPS satellites are a large number of artificial satellites launched by the GPS and orbiting the earth, and each satellite has its own satellite number,
Moreover, the position detection signals (radio waves) are constantly transmitted.

As shown in the figure, the position detecting device of this embodiment is
A beacon receiving means 2 as a first receiving means and a GPS receiving means 4 as a second receiving means are provided. The beacon receiving means 2 receives the position signal transmitted from the beacon, and outputs the position signal from the beacon when passing each beacon installation place by a known method. Further, the GPS receiving means 4 receives the position detection signals transmitted from the respective satellites, and outputs the signals from, for example, four satellites selected by a known method among the received signals to the combination information of the four satellites. Output together with (satellite signal).

The four position detecting signals output from the GPS receiving means are input to the self-position calculating means 6, and the means 6 performs a predetermined calculation based on the input four signals to calculate its own current position. The position is obtained, and the position data (satellite position data) is input to the correction means 8 and the position data and satellites at the time of calculating the position data (four satellites that have transmitted the signals used to calculate the position data). Is input to the offset value calculation means 10.

Positional data (beacon position data) output from the beacon receiving unit 2 is input to the offset value calculating unit 10, and the beacon position data and the time when the beacon position data is input (the beacon installation The offset value (difference) from the satellite position data at the time of passing the place is calculated by the calculating means 10, and the offset value and the satellite at the time of calculating the offset value (the satellite at the time of calculating the satellite position data used for the offset value calculation) The combination information of) is stored in the storage means 12.

Then, the satellite position data calculated by the self-position calculating means 6 as described above is inputted to the correcting means 8 and, at the same time, of the offset values already stored in the storing means 12, is inputted to the correcting means 8. The offset value of the same satellite combination as that of the input satellite position data at the time of calculating the satellite position data is read out and input to the correction means 8, and the correction means 8 subtracts the offset value from the satellite position data (error). Correction is performed, and the satellite position data after the correction is displayed on a display means such as a CRT.
Displayed on the map displayed by 14.

The output of the offset value from the storage means 12 is performed based on the satellite combination information input from the GPS receiving means 4. The storage means 12 stores the combination of satellites and the offset value each time the offset value for a new combination of satellites is calculated.

Next, the operation procedure of the position detecting device will be described in detail with reference to FIG. First, GPS in S1
It is determined whether or not the signal has been received, and if it has not been received, the process proceeds to return. When received, the GPS measurement position, that is, satellite position data is calculated in S2. Then, in S3, it is determined whether or not the satellite combination at the time of calculating the satellite position data is the same as any of the satellite combinations of the offset values already stored. If it is the same as any one, the stored offset value of the same satellite combination is read out in S8,
In S9, the satellite position data is corrected by the offset value and output.

If the offset value of the same satellite combination is not stored, the process proceeds from S3 to S4, where it is determined whether or not the beacon position signal is received. If not, the process proceeds to S10 and the satellite position data is kept as it is. Output.

If received, the process proceeds from S4 to S5, where it is determined whether or not there is a difference between the beacon position data and the satellite position data. If there is no difference, the process proceeds to S10 to output the satellite position data as it is.

If there is a difference, the process proceeds from S5 to S6, the difference (offset value) and the positioning situation at the time of calculating the offset value, such as satellite combination information, are stored, and the process proceeds to S7 to obtain the satellite position data with the offset value. Correct and output.

In the above-mentioned embodiment, once the offset value is stored for each satellite combination, the offset value is used for correction after the same satellite combination.
However, even if the combination of satellites is the same, this offset value changes depending on other positioning situations that change with the passage of time, so it may be updated appropriately. This update may be performed by recalculating the offset value each time a new beacon position signal is received even if the same satellite combination is received, or at an appropriate time, for example, every 24 hours. May be performed.

Further, as described above, the offset value varies not only with the combination of satellites but also with other positioning situations.
Other positioning situations such as pseudo range and SA along with satellite combination
If the values and the like are also stored and the offset values are stored and corrected in consideration of them, the correction can be performed with higher accuracy.

[0029]

The position detecting device according to the present invention, when the position signal (transmitting device position data) is obtained from the position signal transmitting device as described above, the transmitting device position data and the position data (satellite position) based on the satellite at that time. Data)) and the offset value is stored together with the satellite combination, and then the satellite position data is corrected using the offset value of the same satellite combination among the stored offset values. Has been done.

However, as described above, the error of the satellite position data is substantially the same if the combination of satellites is the same, and the position detection based on the transmitting means position data is extremely accurate. Therefore, the offset value obtained as described above almost accurately indicates the error that the satellite position data has when the same satellite combination is used. Therefore, by correcting the satellite position data using this offset value, a more accurate correction can be made. As a result, it is possible to always detect the position with high accuracy.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention.

FIG. 2 is a flowchart showing an operation procedure of an embodiment of the present invention.

[Explanation of symbols]

 2 1st receiving means 4 2nd receiving means 6 Self-position calculating means 8 Correction means 10 Offset value calculating means 12 Storage means 14 Display means

Claims (1)

[Claims] 1. A first receiving means for receiving a position signal transmitted from a position signal transmitting means installed on a road, a second receiving means for receiving a position detecting signal transmitted from a satellite, and the first receiving means. 2 Self-position calculating means for calculating a self-position based on the position detection signal received by the receiving means, self-position calculated by the self-position calculating means and position signal received by the first receiving means Offset value calculation means for calculating an offset value with respect to the obtained self-position, storage means for storing the offset value calculated by the offset value calculation means and the combination of satellites at the time of the offset value calculation, The self-position calculated by the self-position calculation means,
Correction means for correcting the offset value stored in the storage means on the basis of the offset value of the same satellite combination as the satellite combination at the time of the self-position calculation. Detection device.