JP2002040126A - Radiolocation device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable a satellite signal radiolocation device for GPS, etc., to autonomously compute a correction value for correcting dummy distance data obtained by a satellite signal tracking device in the inside, without requiring a dummy distance correction value from a reference station. SOLUTION: A dummy distance correction value arithmetic unit 12 computes the dummy distance correction value from externally supplied position information P1 or a corrected radiolocation position P2 and the dummy distance data Rp from the satellite signal tracking device 11. Then a radiolocation arithmetic unit 13 computes a position P2 from the dummy distance data Rp and dummy distance correction value C. Consequently, the radiolocation device can dispense with a radio receiver for receiving the dummy distance correction value and can make it small-sized and low-cost.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a positioning device for determining a position of a moving body such as a vehicle with high accuracy by using a satellite signal such as GPS.

[0002]

2. Description of the Related Art In a satellite navigation system such as GPS or GLONASS, distances between a moving object equipped with a positioning device and a plurality of satellites are obtained, and the position of the moving object is obtained from the results. In determining this distance, various error factors influence.

[0003] These error factors are caused by the influence of the ionosphere and the troposphere through which the radio waves pass when the radio waves are transmitted from the satellite to the receiver of the positioning device, the influence of the clock of the satellite, the error of the orbit of the satellite, and the like. SA (Sele
ctive Availability). This SA is an intentional loss of accuracy performed by the administrator of the satellite navigation system for its national defense reasons,
It is difficult to predict and correct an error due to this from past received data.

FIG. 3 is a diagram showing a configuration of a conventional positioning device. The above-described various errors are removed, and the position of a moving body on which the positioning device is mounted can be accurately determined (for example, within 1 m). ).

In FIG. 3, a satellite signal from a satellite such as a GPS is received by an antenna 31a and a satellite signal tracking device 31 is received.
Tracks the received satellite signal, outputs pseudo-range data Rp with the successfully tracked satellite, and outputs
Feed to 2. The pseudo distance data Rp obtained by the satellite signal tracking device 31 includes various error factors as described above.

[0006] The correction signal receiving device 33 receives the pseudo distance correction value calculated by the separately installed reference station 34 and transmitted by radio waves via the antenna 33a, and supplies it to the positioning position calculating device 32. .

The positioning position calculation device 32 corrects the supplied pseudo distance data Rp for each satellite with a pseudo distance correction value of the corresponding satellite, and obtains a positioning position P1 from the corrected pseudo distance data.

As described above, in the conventional positioning device shown in FIG. 3, the error component is supplied as a correction value from the reference station 34 which can measure an accurate position in advance, and the pseudo distance data Rp measured based on the correction value is converted to the error value. Correction is performed to remove common error components. For this reason, with this positioning device, highly accurate positioning is possible.

[0009]

However, in a conventional positioning device, it is necessary to receive a pseudo-range correction value at that time from a reference station by a radio receiver in real time.
For this reason, (1) a radio receiver for receiving the pseudo distance correction value is required for each positioning device, so that the size of the positioning device increases and the cost increases accordingly. (2) The radio from the base station If the signal is interrupted, the position is not determined with high accuracy, so it often poses a problem for moving objects such as vehicles.
(3) Depending on the wireless communication means, such as when a public line is used for wireless communication from a reference station, communication costs may be required.
(4) If a public reference station is not used, the reference station must be provided, which causes a problem such as the need for additional burden.

In the case of GPS, intentional deterioration of longitude, which is conventionally called SA, is performed, and it is difficult to predict a correction value for the error component from past received data.
Therefore, a high-precision position cannot be obtained in real time except for the method of transmitting the correction value obtained from the measured value at the reference station at intervals of several seconds as described above.

By the way, in the GPS system, SA has not been performed recently, and it is no longer necessary to consider the SA in calculating the pseudo distance correction value. On the other hand, the effect of the ionosphere and troposphere through which radio waves pass, the effect of the satellite clock, the error of the satellite's orbit, and the like, which are set to the pseudorange correction value, are relatively large. Is predictable in its nature.

The present invention has been made in view of such circumstances, and does not require a pseudo-range correction value from a reference station, and uses a self-correction value for correcting pseudo-range data obtained by a satellite signal tracking device. It is an object of the present invention to provide a positioning device that performs an autonomous calculation inside a device.

[0013]

According to a first aspect of the present invention, there is provided a positioning apparatus comprising:
A satellite signal receiving device 11 for receiving and tracking satellite signals;
A pseudo-distance correction value calculating device 12 for calculating a pseudo-distance correction value C from position information P1 or a corrected positioning position P2 given from outside and pseudo-distance data Rp from the satellite signal receiving device; And a positioning position calculation device 13 that calculates the pseudo position correction value C from the pseudo distance correction value calculation device and outputs the corrected positioning position P2. It is characterized in that the value C is autonomously calculated.

According to the present invention, there is no need to provide a radio receiver for receiving the pseudo-range correction value in the positioning device, so that the positioning device can be reduced in size and cost.

Further, since the pseudorange correction value is obtained autonomously by the positioning device itself, the position can always be obtained with high accuracy.

Since no wireless means is used, there is no possibility that a pseudo distance correction value cannot be obtained, and communication costs are unnecessary.

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the current GPS system, SA is no longer performed, and the pseudorange correction value can be improved only by correction of the influence of the ionosphere and the troposphere. Since the temporal change of these influences is relatively small and has predictability, it is possible to predict the current pseudo distance correction value from the past data. Accordingly, in the present invention, a pseudo positioning correction value is autonomously predicted and calculated by a moving positioning device, such as being mounted on a moving body side, thereby eliminating the need for a radio unit for receiving a pseudo distance correction value from a reference station. ing.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a block diagram illustrating a configuration of a positioning device according to an embodiment of the present invention. In the following description, it is assumed that the positioning device is mounted on a moving body such as a vehicle.

In FIG. 1, a satellite signal receiving device (hereinafter, referred to as a satellite signal receiving device)
The satellite signal tracking device 11 receives the G signal received by the antenna 11a.
A satellite signal from a satellite such as a PS is received, and the received satellite signal is tracked. Pseudorange data Rp measured for each of a plurality of satellites between the plurality of successfully tracked satellites and the positioning device
And outputs the correction value calculation device 12 and the positioning position calculation device 1
Supply 3

The pseudo-range data Rp measured by the satellite signal tracking device 11 is based on the influence of the ionosphere and troposphere through which radio waves pass, the influence of the satellite clock, the error of the satellite orbit, and the like, which cannot be avoided in the satellite navigation system. Contains. However,
SA that has been conventionally performed by the GPS system is no longer performed, and the calculation of the pseudo distance correction value includes:
It is no longer necessary to consider SA. The remaining error factors are different from SA, which is intentional deterioration of accuracy, and the nature of the change has predictability.

The correction value calculating device 12 predicts and calculates the pseudo distance correction value C in consideration of the error factor, and measures the pseudo distance data R from the satellite signal tracking device 11.
The pseudo distance correction value C is calculated based on p and the position information P1 given from the outside or the corrected and calculated positioning position P2, and is supplied to the positioning position calculation device 13.

The positioning position calculating device 13 calculates the pseudo distance data Rp of a plurality of satellites from the satellite signal tracking device 11.
Is corrected by the pseudo distance correction value C from the positioning position calculation device 13, and the corrected positioning position P2 is calculated and output.

A series of operations of the positioning device thus configured will be described step by step. In the following description, a case where the pseudo distance correction value C is predicted by a first-order approximation to the elapsed time will be described as an example.

First, when the positioning device is powered on, the positioning device is placed at a known position, and the position information P of the known position is set.
Enter 1. The input of the position information P1 is performed by, for example, manually inputting a numeric key.

Next, the correction value calculating device 13 determines a true pseudo distance Rr between the position P1 and each satellite from the known position P1 and the orbital position of each satellite at that time. From the difference between the true pseudo-range Rr and the measured pseudo-range data Rp, the instantaneous pseudo-range correction value A1 for each satellite at that time is calculated.
Ask for.

Since this instantaneous pseudo distance correction value A1 changes with time, the instantaneous pseudo distance correction value A1 moves to the known position P1 for a predetermined time T
The moving object on which the positioning device is mounted is kept stationary for only 1 (for example, several minutes), and the instantaneous pseudo distance correction value A1 'is similarly obtained again after the predetermined time T1 has elapsed.

From this, the pseudo distance correction change amount B1 per unit time can be obtained by B1 = (A1'-A1) / T1.

Then, using the instantaneous pseudo distance correction value A1 '(or A1), the pseudo distance correction change amount B1 and the elapsed time t after measuring the instant pseudo distance correction value A1', the pseudo distance correction value C1 is obtained. , C1 = A1 ′ + B1 × t.

The correction value calculating device 13 supplies the obtained pseudo distance correction value C1 to the positioning position calculating device 13. In the positioning position calculation device 13, the satellite signal tracking device 11
The pseudo distance data Rp measured by
1, the true pseudorange Rr (= Rp-C1) is obtained for each satellite, and the corrected and calculated position P2 of the moving object having the positioning device mounted thereon is measured at each time point.

As described above, only the satellite for which the pseudo distance correction value C1 was obtained at power-on is used, and the true pseudo distance Rr obtained by correcting the measured pseudo distance data Rp of each satellite with the pseudo distance correction value C1 is used. Therefore, since the positioning calculation is performed by performing autonomous calculation within the self, a highly accurate position is always required.

In the above embodiment, the position P1 of the known point is input when the positioning device is powered on. However, the position P1 can be given as follows instead. That is, a single positioning average value measured while the moving body on which the measurement device is mounted is kept stationary for a predetermined time (for example, one hour or more) at night or the like is used as the initial position. If not moved after the power is turned off, the last position of the previous day should be the initial position.

Further, in the above-described embodiment, the stationary position is kept at the known position P1 for the predetermined time T1. May be used.

Next, when the positioning calculation is performed using only the satellite for which the pseudo distance correction value C1 was obtained when the power was turned on, a satellite that was not tracked when the power was turned on was determined.
When newly tracking and using the positioning calculation, the pseudorange correction value C2 for the satellite is obtained as follows, and the measured pseudorange data Rp of the satellite is corrected.

That is, the pseudo-range data Rp at the time of tracking the satellite and the true pseudo-range Rr obtained by using the corrected and calculated high-precision positioning position P2 obtained from the positioning position calculating device 13 From the difference, the instantaneous pseudo distance correction value A2 is obtained. Then, the measured pseudo distance data Rp at the time when a predetermined time T2 (for example, several minutes) elapses
The instantaneous pseudo distance correction value A2 'is obtained from the difference between the actual pseudo distance Rr and the true pseudo distance Rr obtained by using the high-precision positioning position P2 obtained from the positioning position calculation device 13 at that time.

The instantaneous pseudo distance correction values A2, A
2 ', using the predetermined time T2, the pseudo distance change correction amount B2 for the satellite is obtained by B2 = (A2'-A2) / T2.

Using the instantaneous pseudo distance correction value A2 '(or A2), the pseudo distance correction change amount B2, and the elapsed time t after measuring the instant pseudo distance correction value A2', the pseudo distance correction value C2 is calculated. , C2 = A2 ′ + B2 × t.

The pseudo distance correction value C2 obtained by the correction value calculation device 12 is supplied to the positioning position calculation device 13. From the time when the pseudo distance correction value C2 is obtained, the positioning position is obtained by using the newly tracked satellite. Therefore, even if the visible satellite used for positioning changes, high-accuracy position measurement can be continuously performed.

The pseudo distance correction change amount B described above
It is not necessary to continuously track the satellite during the predetermined times T1 and T2 for calculating 1,1 and B2, and it is sufficient that stable tracking is performed at the time of measurement. Further, since the pseudo distance correction values C1 and C2 are not related to the tracking, even if the tracking is interrupted, the pseudo distance can be corrected from the time of re-tracking.

In the embodiment described above, the pseudo distance correction values C1 and C2 are used as the instantaneous pseudo distance correction values A1 and A2.
2. The example in which the pseudo-range change correction amounts B1 and B2 and the elapsed time t are used to obtain the first-order approximation has been described. Alternatively, the pseudo-range change correction amounts B1 and B2 may be set to zero.
A second-order approximation or a second-order or higher-order approximation may be used.

FIG. 2 is a diagram showing a system configuration which is mounted on a moving body or the like and supplies a known position or the like as an initial value to a moving positioning device.

In FIG. 2, a positioning device 10 is the same as the positioning device described with reference to FIG. 1, and is mounted on a moving body and moves. The positioning device 10 has an input terminal IN for inputting a known position P1 and the like. The reference value supply device 20 is installed at a fixed position, and is configured to supply position information P1 of the fixed position to the positioning device 10 via the input terminal IN.

By installing such a reference value supply device 20 for each predetermined range, the positioning device 10 can be connected to the reference value supply device 20 installed at an arbitrary place, and can be used when necessary. , The reference position P1 can be input as an initial value.

In particular, as shown in FIG. 1 and FIG. 2, in the positioning device according to the embodiment of the present invention, autonomous correction is performed by approximation calculation.
Becomes larger with time, so that when a predetermined time (for example, one hour) has elapsed, the nearest reference value supply device 20 can be accessed to newly initialize the reference value.
In this case, only the instantaneous pseudo distance correction values A1 and A2 may be corrected.

In FIG. 2, a known reference position P1 is input from the reference value supply device 20,
Instead, an instantaneous pseudo distance correction value A and a pseudo distance correction change amount B can be supplied. In this case, in FIG. 2, the inputs to the correction value calculation device 12 need only be the instantaneous pseudo distance correction value A and the pseudo distance correction change amount B, and the pseudo distance data Rp measured from the satellite signal tracking device 11 is sufficient. There is no need to input the corrected and calculated positioning position P2 from the positioning position calculation device 13.

Further, the reference value supply device 20 shown in FIG.
May itself be a reference station. In addition, a configuration is adopted in which the instantaneous pseudo distance correction value A and the pseudo distance correction change amount B are supplied to the reference value supply device 20 by wire transmission or wireless transmission from a reference station provided at a distant place. I can do it. In this case, the reference value supply device 20 is an information terminal such as a personal computer or a mobile phone, and is configured to use the instantaneous pseudo distance correction value A and the pseudo distance correction change amount B distributed from the electronic reference point via the Internet or the like. Can also.

When the positioning device is provided with a radio receiver, when a predetermined time has elapsed (for example, every hour),
The correction value may be corrected to the correction value from the reference station in combination with the autonomous calculation positioning of the above embodiment. Further, when the positioning device or a device related to the positioning device also has a transmission unit for transmitting the mobile positioning position to the outside, the pseudo distance correction value and the pseudo distance correction change amount are externally transmitted. Only when the pseudo-range correction value and the pseudo-range correction change amount transmitted from each positioning device or the like are shifted by a predetermined value or more by an external monitoring device or the like, the correction signal receiving device is operated, and the It can be configured to correct the correction value.

In the embodiment of the present invention, the measured pseudorange is corrected, but the influence of the SA on the carrier of the GPS system is eliminated. Therefore, using the carrier phase of the GPS system,
Positioning can be performed. That is, the initial integer value bias of the carrier is obtained from the initial position, and the correction value for the carrier is obtained in the same manner as the instantaneous pseudo-range correction value and the pseudo-range correction change amount described above. To find a suitable positioning position.

[0048]

According to the present invention, there is no need to provide a radio receiver for receiving a pseudo distance correction value in the positioning device, so that the positioning device can be reduced in size and cost.

Further, since the pseudorange correction value is obtained autonomously by the positioning device itself at all times, the position can always be obtained with high accuracy.

Further, since the wireless means is not used, a situation in which a pseudo distance correction value cannot be obtained does not occur, and communication cost is unnecessary.

[Brief description of the drawings]

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

FIG. 2 is a diagram showing a system configuration using the positioning device of the present invention.

FIG. 3 is a diagram showing a configuration of a conventional positioning device.

[Explanation of symbols]

 Reference Signs List 11 satellite signal tracking device 12 correction value calculation device 13 positioning position calculation device 20 reference value supply device Rp measured pseudo distance P1 position of known point P2 correction calculated positioning position C1, C2 pseudo distance correction value

Claims (1)

[Claims] 1. A satellite signal receiving apparatus for receiving and tracking a satellite signal, position information given from outside or a corrected positioning position, and pseudorange data from the satellite signal receiving apparatus,
A pseudo distance correction value calculating device for calculating a pseudo distance correction value; a pseudo distance correction value from the satellite signal receiving device and a pseudo distance correction value from the pseudo distance correction value calculating device; And a positioning position calculation device that outputs the pseudo-range correction value.