JP2802020B2 - Navigation device with position correction function - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of calculating an instantaneous vehicle position, which is obtained by calculating information collected every moment, based on position information identified from the beacon electric wave when passing through a beacon electric wave reception area. The present invention relates to a navigation device having a position correction function for performing correction.

[0002]

2. Description of the Related Art A large number of low-power relay stations are arranged along a road, and local traffic information and road information are continuously transmitted in the form of beacon radio waves using a common radio frequency. Vehicles traveling on the VICS (Vehicle Information and Communication Systems) use this information as necessary.
ystem: Road-to-vehicle information system) Beacon systems are being put into practical use. The VICS beacon system aims at effective use of roads by realizing smooth road traffic, rationalization of road management, timely provision of information to drivers, and the like.

In the VICS beacon system, a local receiving area is formed by transmitting a beacon radio wave from a pair of transmitting antennas provided above a road. On the other hand, on the vehicle side,
A beacon receiver is installed, and the beacon receiver has (a) a data reception function that extracts various information from the FM modulation component of the beacon radio wave, and (b) a direct detection position directly below the antenna using the AM modulation component of the beacon radio wave. Also has a detection function.

[0004] Various types of information communicated by the VICS beacon system include position information for specifying a reception area (coordinate position where a transmitting antenna is installed), vehicle traveling direction, road lane information, intersection name, toll road ahead. (Such as fixed tariffs) and fluid (such as instantaneous traffic congestion, display of construction sections and detours, weather information, road surface conditions, etc.).

[0005] In addition, the direct detection function of the beacon receiver,
Various information communicated by data can be displayed at an appropriate timing on a CRT screen mounted on a running vehicle, and an instantaneous vehicle position calculated and calculated by a navigation device mounted on the vehicle can be displayed. It can also be used for correction.

According to the direct detection function of the beacon receiver,
The position immediately below the transmitting antenna in the receiving area can be detected with high accuracy within ± several meters. Therefore, for example, the instantaneous vehicle position calculated by the navigation device is replaced with the coordinate position of the transmitting antenna for data communication at the timing of detecting the position immediately below, and the subsequent vehicle position is calculated based on this new initial value. To continue. As a result, the accuracy of the instantaneous vehicle position displayed on the map image can be dramatically improved.

The correction of the vehicle position using the output of the beacon receiver uses a navigation device of a type in which errors accumulate as the vehicle runs unless artificial correction is performed, for example, a gyro, a gas inertia sensor, or the like. It is effective in a navigation device. Every time the accumulated position error passes immediately below the transmitting antenna of the beacon radio wave, it is replaced with the transmitting antenna position information and is canceled at once.

On the CRT screen of the navigation device, the position of the vehicle superimposed on the map image gradually protrudes from the road as the vehicle travels. The position is corrected.

FIG. 7 is an explanatory diagram of the VICS beacon system. In FIG. 7, (a) is a reception state of the beacon radio wave,
(b) shows a beacon wave in the in-phase region, and (c) shows a beacon wave in the out-of-phase region.

In FIG. 7A, a relay station 71 is connected to a road 7.
And a pair of transmitting antennas 72A, 7 installed in the sky position
2B and a transmitting antenna 72 directed toward the in-phase region.
7A through the transmitting antenna 72B directed to the in-phase region side in FIG.
Beacon radio waves in the reverse phase region are transmitted.

A gigahertz band radio channel is allocated to the beacon radio wave. The beacon radio wave is an FM modulation component obtained by FM-modulating a data signal of various information, and an analog amplitude signal for detecting a position immediately below the transmitting antennas 72A and 72B. And an AM modulation component obtained by AM-modulating

The beacon radio waves in the in-phase region of FIG.
The beacon radio waves in the opposite phase region of (c) share the data signal (FM modulation component), but the phase of the analog amplitude signal (AM modulation component) is opposite. That is, in the beacon radio wave in the in-phase region, the synchronization signal of the data signal and the analog amplitude signal have an in-phase relationship, but in the beacon radio wave in the anti-phase region, the synchronization signal of the data signal and the analog amplitude signal have an anti-phase relationship.

Therefore, immediately below the transmitting antennas 72A and 72B, the analog amplitude signals in the in-phase region and the opposite-phase region interfere with each other and cancel each other, forming a minimum point of the reception intensity of the analog amplitude signal.

A vehicle 73 traveling on a road 70 receives a beacon radio wave from a beacon receiver in the vehicle through a receiving antenna 74. Then, when the reception intensity of the beacon radio wave increases to a level at 100 to 500 m from the position 75 immediately below, the demodulation of the FM modulation component is started, the data signal is separated, and various data are accumulated. The driver can use various information such as character information and still image information through the CRT screen in the vehicle.

When the reception intensity of the beacon radio wave reaches a set level (corresponding to 30 to 50 m from the position directly below), the beacon receiver starts detecting the position directly below using an analog amplitude signal. The detection of the position immediately below (1) detects the minimum point of the reception intensity of the analog amplitude signal, (2) detects the in-phase / out-phase (or out-of-phase / in-phase) conversion point of the analog amplitude signal and the synchronization signal, etc. It is performed by the method described above.

The beacon receiver compares the phase relationship between the analog amplitude signal and the synchronization signal to identify an in-phase region and an out-of-phase region. For example, the traveling direction of the vehicle 73 with respect to the relay station 71 is obtained from the phase relationship between the analog amplitude signal and the synchronization signal before detecting the positions immediately below the transmitting antennas 72A and 72B.

According to the identified traveling direction, only the data related to the front of the traveling direction of the vehicle 73 is selected from the various stored data, and is displayed on the CRT screen mounted on the vehicle at the timing when the immediately lower position is detected. You. Information such as intersections that have passed is useful for vehicles passing in the opposite lane, but is of no value to the vehicle 73 in principle.

The beacon receiver further corrects the position of the vehicle 73 calculated by the navigation device mounted on the vehicle. Vehicle 73 calculated by the navigation device
Is replaced with the position coordinates of the relay station 71 stored as various data at the timing when the immediately lower position is detected. Thereafter, the navigation device calculates the position of the vehicle 73 every moment using the position coordinates of the relay station 71 as initial values.

[0019]

In FIG. 7A, the reception intensity of the beacon radio wave and the reception intensity of the analog amplitude signal are shown by gentle curves, respectively. Fluctuates drastically during running as shown by the dotted line in the figure. Along with this, the reception strength of the analog amplitude signal also fluctuates drastically as shown by the dotted line in the figure.

Beacon radio waves in the gigahertz band have high straightness, and interfere with each other in a complicated manner under the influence of blocking or reflection by surrounding buildings, street trees, other vehicles (traffic conditions) on the road, etc., and the transmitting antenna 72A. , 72B other than the position directly below,
There is a possibility of forming a minimum point of the analog amplitude signal.

Therefore, in the method of (1) detecting the minimum point of the reception intensity of the analog amplitude signal and identifying the position immediately below, the false minimum point just before the position immediately below the transmitting antennas 72A and 72B is detected, and There is a possibility of misjudging as a position.

In a region where the beacon electric wave transmitted by the transmitting antenna 72A and the beacon electric wave transmitted by the transmitting antenna 72B overlap each other, the mutual analog amplitude signals cancel each other, thereby lowering the reception strength of the analog amplitude signal, The accuracy of the phase comparison of the amplitude signal is reduced. And
Fluctuations in the reception intensity of the beacon radio wave due to the influence of the surrounding environment further reduce the accuracy of the phase comparison of the analog amplitude signals through fluctuations in the reception intensity of the analog amplitude signals.

Accordingly, (2) the method of detecting the in-phase / out-phase (or out-of-phase / in-phase) conversion point of the analog amplitude signal and the synchronization signal to identify the position immediately below the analog amplitude signal and the synchronizing signal causes a problem when the reception strength of the beacon radio wave is low. In this case, the error of the identified position immediately below is enlarged.

On the other hand, the reception intensity of the beacon radio wave is shown in FIG.
(a) Not only the traveling direction of the road 70 but also the road width direction of the road 70 greatly changes. Sending antenna 72
A and 72B are usually provided on the lane at one end of the road 70. In this case, the reception intensity of the beacon radio wave is significantly reduced in the lane at the other end compared with the lane at the one end, and if the road is wider than three lanes on one side, the detection of the position immediately below is started. In some cases, the set level cannot be reached, and various data transmitted from the relay station 71 cannot be used normally.

On a wide road where the transmitting antennas 72A and 72B are provided on the lane at one end of the road 70,
Each time the lane is moved toward the lane at the other end, the detection error of the position immediately below increases.

On the other hand, in recent years, a navigation device using absolute position measurement using a communication satellite and a navigation device using a plurality of sensors such as an acceleration sensor in a gyro have been put to practical use, and the accuracy of the calculated vehicle position has been increased. And the accumulation of errors in the vehicle position during traveling is not so remarkable as in the past.

Therefore, when the vehicle is passing through a lane far from the transmitting antennas 72A and 72B or when the traffic intensity of the beacon signal is remarkably reduced, for example, when the surrounding traffic condition interrupts the beacon signal, the error in detecting the position immediately below is large. too much,
“Position correction by replacement” may be performed on a vehicle position having a larger error than the vehicle position calculated by the navigation device.

An object of the present invention is to provide a navigation device with a position correction function in which the position correction by replacement does not increase the error of the vehicle position.

[0029]

FIG. 1 is an explanatory diagram of a basic configuration of the present invention. In FIG. 1, a navigation device with a position correction function according to the first aspect of the present invention includes a calculating means 12 for calculating the instantaneous position of a running vehicle 11 based on information collected instantaneously on the vehicle 11 side; The beacon receiver 13 that identifies the position information of the reception area from the beacon radio wave and detects the timing of passing the beacon radio wave at the closest position to the transmission unit 10 when passing through the reception area of the beacon radio wave arranged at Correction means 14 for correcting the instantaneous vehicle position calculated by the calculation means 12 based on the position information identified by the beacon receiver 13 when the passage timing is detected. In the navigation device with the correction function, the closest approach distance to the transmitting unit 10 when passing through the reception area is identified, and the error of the passing timing is identified. When the difference between the reference vehicle 15 for estimating the distance and the instantaneous vehicle position by the calculating unit 12 and the position information by the beacon receiver 13 is smaller than the error distance, the correction by the correcting unit 14 is performed. Control means 16 for canceling
And is provided.

According to a second aspect of the present invention, there is provided the navigation device with the position correcting function according to the first aspect of the present invention, wherein the reference means 15 identifies a running direction from a beacon radio wave and forward / reverses the running direction. And a reference means for making the error distance different based on the distinction.

According to a third aspect of the present invention, there is provided a navigation device having a position correcting function, comprising: a calculating means for calculating the instantaneous position of a running vehicle based on information continuously collected on the vehicle side; A beacon receiver that identifies position information of the reception area from the beacon radio wave when passing through the arranged reception area of the beacon radio wave, and detects a passage timing of the closest position to the transmission unit of the beacon radio wave, Correction means for correcting the instantaneous vehicle position calculated by the calculation means based on the position information identified by the beacon receiver, when a passage timing is detected. Reference means for identifying a reception state of a beacon radio wave when passing through the reception area, and estimating an error distance of the passage timing; Control means for stopping the correction by the correction means when a difference between the instantaneous vehicle position by the step and the position information by the beacon receiver is smaller than the error distance. .

[0032]

According to the navigation device with the position correction function of the present invention, the vehicle position calculated by the navigation device is not blindly replaced with the position information acquired through the beacon radio wave, but the position immediately below the vehicle detected in the reception area of the beacon radio wave. Is estimated, and only when the vehicle position calculated by the navigation device is significantly different from the range obtained by adding the detection error to the position information of the reception area (the position immediately below the transmitting antenna) obtained from the beacon radio wave, "Position correction by replacement" is executed.

In the navigation device with the position correcting function of the first aspect, the reference means 15 and the control means 16 are added. The reference unit 15 estimates the detection error of the position immediately below the sending unit 10 according to the distance from the sending unit 10 when passing through the position directly below the sending unit 10 (more precisely, on a traversing line of a road passing directly below the sending unit 10). , Set.

If the distance from the transmitting unit 10 is large, the reception intensity of the beacon radio wave decreases, the possibility of erroneous detection of the passing timing of the vehicle 11 at the closest position of the transmitting unit 10 increases, and the detection error of the passing timing also increases. Increase. The control means 16 determines whether or not the correction should be performed, and stops the correction if the correction is inappropriate.

The distance from the transmitting unit 10 is determined based on (1) a distinction between the forward direction and the reverse direction of the traveling direction, (2) a sensor that detects a white line to identify the current traveling lane, and (3) a reception intensity of a radio wave. It is identified by a detecting device or the like for estimating the traveling lane.

The calculating means 12 calculates the position of the vehicle 11 every moment based on information collected every moment through a gyro, a gas inertia sensor, a GPS receiver and the like. When the beacon receiver 13 passes through the reception area of the beacon electric wave,
At least the data of the position information of the receiving area is accumulated from the beacon radio wave, and the timing at which the vehicle 11 passes the closest position of the transmitting unit 10 is detected.

The correction means 14 executes "position correction by replacement" for replacing the position of the vehicle 11 calculated by the calculation means 12 with the position information of the reception area acquired by the beacon receiver 13. The correction unit 14 is, for example, the transmitting unit 10
At the passage timing of the closest position to the
Replaces the calculated position of the vehicle 11 with the position information of the reception area of the beacon receiver 13.

In the navigation device with the position correcting function according to the second aspect, the error distance is made different based on the distinction between the forward direction and the reverse direction of the traveling direction. For example, in the VICS beacon system, the transmitter is installed such that a vehicle 73 traveling in the in-phase region (forward direction) of FIG.
72B. Therefore, the distance is short in the forward direction, and long in the reverse direction.

In the navigation device with the position correction function according to the third aspect, the reception state of the beacon radio wave when passing through the reception area is identified, and the error distance of the passage timing is estimated. The reception state of the beacon radio wave is affected not only by the distance from the transmitter, but also by the environment around the vehicle, traffic conditions, and the like. The possibility of detection increases, and the detection error of the passage timing also increases.

The reception state of the beacon radio wave includes (1) the reception intensity of the beacon radio wave, (2) the data error rate due to the FM modulation component, and (3) the analog amplitude signal having a certain amplitude or less after starting the detection of the position immediately below. The received travel distance and the like are detected and identified. In the case of (3), since it is determined whether or not to execute the correction after passing the position immediately below, it is necessary to additionally correct the travel distance after passing the position immediately below.

[0041]

FIG. 2 is an explanatory diagram of the configuration of the navigation system of the first embodiment, FIG. 3 is an explanatory diagram of the relationship between the traveling lane and the detection error, and FIG. 4 is a flowchart of the arithmetic / display unit. In FIG. 3, (a) shows the traveling lane, and (b) shows the detection error.

Here, the error X is set according to the distinction between the forward direction and the reverse direction (main direction / slave direction) of the traveling direction, and the vehicle position by the navigation device and the VICS beacon receiver are provided at the timing of detecting the position directly below. Only when the difference from the transmitted antenna position exceeds the error X, the “position correction by replacement” is executed. In other words, the vehicle position is corrected to the transmitting antenna position only when the vehicle position is displayed at a position outside the range of the front and rear X centered on the transmitting antenna position.

In FIG. 2, a GPS receiver 21 receives a radio wave transmitted from a geostationary satellite 25 to detect a current position of a vehicle. The receiving unit 21A separates necessary electric signals from the received radio waves and converts them into data for obtaining the current position of the vehicle. The data is immediately sent to the arithmetic / display unit 23 via the data sending unit 21B.

The VICS beacon receiver 22 receives a beacon radio wave transmitted from a transmitting antenna 24 disposed above the lane on one side of the road, and stores various information data including the installation position of the transmitting antenna 24. I do. Further, by detecting the analog amplitude signal, the position immediately below the transmitting antenna 24 is detected, and the data of various information is used at the detection timing of the position immediately below.

The beacon radio wave received from the antenna provided on the rooftop of the vehicle is amplified by the high frequency circuit 22, band-selected, and converted into an intermediate frequency signal. The intermediate frequency signal is further band-selected through the intermediate frequency circuit 22B and converted to a baseband signal.

The FM data demodulation circuit 22C extracts FM modulation components including digital signals of various data from the baseband signal, and restores the original digital data from the FM modulation components. The restored various data is transmitted to the communication unit 23 of the arithmetic / display unit 23 through the communication unit 22E and the arithmetic / display unit 23.
B.

The AM amplitude signal demodulation circuit 22D separates an analog amplitude signal from a baseband signal. The immediately below position detection circuit 22F detects a conversion point of the phase state (in-phase / out-of-phase relationship) between the analog amplitude signal and the synchronization signal as shown in FIGS. Identify the location. The traveling direction identification circuit 22G detects the phase relationship between the analog amplitude signal and the synchronization signal before the timing of detecting the immediately below position, and identifies the distinction between the forward direction and the reverse direction of the traveling direction.

The arithmetic / display unit 23 is set to G
The vehicle position data obtained by the PS receiver 21 is input to the I / O unit 23.
A is input to the CPU 23E through A. In the CPU 23E,
An operation of superimposing the vehicle position on the map image data is performed. The formed display image data is displayed as an image through the display unit 26.

On the other hand, when the vehicle enters the transmission area of the transmission antenna 24, first, various data through the FM modulation component is input to the CPU 23E through the communication unit 23B,
The PU 23E selects necessary data according to the distinction of the traveling direction and stores the data in the memory 23F. Sending antenna 24
Is stored in the memory 23F in a state where it is translated into a data format for navigation used by the arithmetic / display unit 23. The installation position of the transmitting antenna 24 is called back to the CPU 23E at the timing of detecting the position immediately below.

The traveling direction identified by the traveling direction identification circuit 22G is input to the CPU 23E through the I / O unit 23D. The timing of detecting the position directly below the position detected by the position detection circuit 22F is input to the CPU 23E through the I / O unit 23C.

The CPU 23E starts the position correction interrupt program at the timing of detecting the position directly below, and compares the vehicle position calculated based on the data from the GPS receiver with the installation position of the transmitting antenna 24 to obtain a difference. Only when this difference is larger than the set value of the error determined according to the traveling direction, the calculated vehicle position is replaced with the installation position of the transmitting antenna 24.

In FIG. 3A, the traveling direction passing through the VICS beacon transmitting antenna 24 when viewed to the left is the main direction, and the traveling direction passing through when viewed to the right is the subordinate direction. Also, VIC
Before and after passing through the closest position of the S-beacon transmitting antenna 24, the relationship between the analog amplitude signal and the synchronization signal changes from the same phase to the opposite phase in the main direction, and changes from the opposite phase to the same phase in the slave direction.

Further, even on a road having a total width of 16 m and two lanes on each side, as the distance from lanes 1, 2, 3, and 4 and the VICS beacon transmitting antenna 24 increases, the range in which the position immediately below can be detected increases, and the vehicle repeats many times. The expected value (average value) of the obtained detection error significantly increases.

In FIG. 3B, the expected value of the detection error is:
It increases linearly as the distance from the VICS beacon transmitting antenna 24 increases, and up to 8 in the main direction lane 2
m, but up to 16 m in the lane 4 in the secondary direction.

In FIG. 4, when the CPU 23E of the arithmetic / display unit 23 in FIG. 2 starts the position correction interruption program, in step 41, the difference between the vehicle position A obtained by the GPS receiver 21 and the installation position B of the transmitting antenna 24 is determined. Y is calculated. On the other hand, in step 42, an error limit X is set according to the traveling direction of the vehicle. That is, if the traveling direction is the main direction, 6 m is set, and if the traveling direction is the sub direction, 12 m is set.

If the difference Y between the vehicle position A by the GPS receiver 21 and the installation position B by the VICS beacon receiver 22 exceeds the error limit X, step 43
Then, the vehicle position A obtained by the GPS receiver 21 is replaced with the installation position B of the transmitting antenna 24, but the difference Y is equal to the error limit X.
If not, no correction is performed.

The corrected vehicle position is displayed on the display unit 26 of the calculation / display unit 23 so as to be superimposed on the map image. Thereafter, the calculation of the image data in the CPU 23E is corrected at the installation position B of the transmission antenna 24. Starting from the initial value,
It is executed every moment based on the data of the GPS receiver 21.

FIG. 5 is an explanatory diagram of the configuration of the navigation system according to the second embodiment, and FIG. 6 is an explanatory diagram of setting an error limit. 6A shows an error limit setting program, and FIG. 6B shows an error limit setting program. Here, the error limit X is set according to the distinction of the reception intensity level of the beacon radio wave at the timing of detecting the position immediately below, and the vehicle position and the VI by the GPS receiver are set.
“Position correction by replacement” is executed only when the difference between the CS antenna and the transmitting antenna position by the CS beacon receiver exceeds the error limit X.

In FIG. 5, a receiver 51A of the GPS receiver 51 separates data on the current position of the vehicle from radio waves transmitted from the geostationary satellite 55. The data is sent to the arithmetic / display unit 53 through the data sending unit 51B.

The VICS beacon receiver 52 receives the beacon radio wave transmitted from the transmitting antenna 54 and separates the data on the installation position of the transmitting antenna 54. Further, by detecting the analog amplitude signal, the position immediately below the transmitting antenna 54 is identified. In the VICS beacon receiver 52, the beacon radio wave is converted into an intermediate frequency signal through the high frequency circuit 52. The intermediate frequency signal is further band-selected through the intermediate frequency circuit 52B and converted to a baseband signal.

The FM data demodulation circuit 52C extracts the FM modulation component from the baseband signal and restores the data of the installation position of the transmitting antenna 54. AM amplitude signal demodulation circuit 5
2D extracts an analog amplitude signal from a baseband signal. The immediately below position detection circuit 52F detects the in-phase / out-of-phase conversion point of the analog amplitude signal and the synchronization signal, and identifies the position immediately below the transmitting antenna 54. Travel direction identification circuit 52G
Examines the phase relationship between the analog amplitude signal and the synchronization signal to identify the traveling direction.

The radio wave intensity detection circuit 52H rectifies, smoothes and amplifies the received signal of the beacon electric wave, and creates an analog electric signal corresponding to the received intensity of the beacon electric wave. Calculation/
The CPU 53E of the display 53 samples the analog electric signal through the I / O unit 53H at the timing of detecting the position immediately below, and estimates the reception intensity of the beacon radio wave.

In the normal state, the arithmetic / display unit 53
The vehicle position data from the PS receiver 51 is transmitted to the I / O unit 53A.
The CPU 53E forms display image data in which a vehicle position mark is superimposed on a map image based on the vehicle position data. The display image data is displayed as an image through the display unit 56.

On the other hand, when the vehicle enters the reception area of the beacon radio wave, first, the data of the installation position of the transmitting antenna 54 is separated through the FM modulation component, and is input to the CPU 53E through the communication unit 53B. The CPU 53E stores the data of the installation position of the transmitting antenna 54 in the memory 23F, and recalls the data to the CPU 53E at the timing of detecting the position immediately below.

The running direction of the vehicle is input to the CPU 53E through the I / O unit 53D, and the timing of detecting the position immediately below the vehicle is input to the CPU 53E through the I / O unit 53C. CPU5
3E starts the position correction interrupt program at the timing of detecting the position directly below, and transmits the vehicle position by the GPS receiver 51 and the transmission antenna 54 by the VICS beacon receiver 52.
Find the difference from the installation position, and only if this difference is larger than the error limit determined according to the reception strength of the beacon radio wave,
The vehicle position by the GPS receiver 51 is replaced by the installation position of the transmitting antenna 54 by the VICS beacon receiver 52.

In FIG. 6 (a), as shown in FIG. 3 (a), on a four-lane road where the transmitting antenna 54 is installed on the lane 1 side, the vehicle travels based on the reception intensity of the beacon radio wave at the timing of detecting the position immediately below. The lane can be identified. That is, as the distance from the lanes 1, 2, 3, 4 and the transmitting antenna 54 increases, the reception intensity of the beacon radio wave decreases, and the range (error limit) in which the position immediately below can be detected also increases.

In FIG. 6 (b), the flowchart of the arithmetic / display unit in the second embodiment is configured by replacing step 42 of the flowchart of FIG. 4 with step 62 of FIG. 6 (b).

In step 42 of FIG. 4, the traveling direction of the vehicle is identified, and an error limit X is set according to the distinction between the main direction and the subordinate direction. On the other hand, in step 62 in FIG. The reception intensity of the beacon radio wave at the detection timing is detected, and an error limit X is set according to the level of the reception intensity of the beacon radio wave.

Then, as in the case of the first embodiment, GP
The difference Y between the vehicle position A by the S receiver 51 and the installation position B of the transmitting antenna 64 by the VICS beacon receiver 52 is calculated, and only when the difference Y exceeds the error limit X, the vehicle position A is changed to the transmitting antenna 54. To the installation position B.

[0070]

According to the navigation device having the position correcting function of the present invention, the calculated vehicle position is not blindly replaced by the installation position of the transmitting antenna. It doesn't happen. That is, there is no concern that the error of the vehicle position is increased by the correction. Therefore, even in a lane opposite to the transmitting antenna on a wide road, a certain degree of accuracy and reliability can be ensured for position correction.

Conventionally, even when the reception intensity of the beacon radio wave cannot be started because the reception intensity of the beacon radio wave is too weak, the level of the reception intensity of the beacon radio wave for starting the detection of the immediately below position is lowered to actively collect data. And this data can be effectively used by a method of using the low-precision position detection with low accuracy. That is, conventionally discarded data without being used because it is impossible to detect the position directly below can be used in a state where the limit is conscious.

According to the navigation device having the position correction function of the second aspect, the position correction can be performed by adding only a slight program change of the arithmetic unit while maintaining the existing circuit configuration without adding a special circuit or sensor. A function to secure certain accuracy and reliability can be realized.

According to the navigation device with the position correcting function of the third aspect, when not only the lane opposite to the transmitting antenna on a wide road but also the surrounding buildings and street trees are disturbing the beacon electric wave, the central separation is performed. Even when a tall wall is provided in the belt, even when surrounding traffic conditions prevent normal reception of beacon radio waves, certain accuracy and reliability of position correction can be ensured.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram of a basic configuration of the present invention.

FIG. 2 is an explanatory diagram of a configuration of a navigation system according to a first embodiment.

FIG. 3 is an explanatory diagram of a traveling direction and a detection error.

FIG. 4 is a flowchart of a calculation / display device.

FIG. 5 is an explanatory diagram of a configuration of a navigation system according to a second embodiment.

FIG. 6 is an explanatory diagram of setting of an error limit.

FIG. 7 is an explanatory diagram of a VICS beacon system.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Transmission part 11 Vehicle 12 Operation means 13 Beacon receiver 14 Correction means 15 Reference means 16 Control means

──────────────────────────────────────────────────続 き Continued on the front page (58) Fields surveyed (Int. Cl. ⁶ , DB name) G01S 1/00-1/68 G01C 21/00

Claims (3)

(57) [Claims] 1. A calculating means (12) for calculating an instantaneous position of a running vehicle (11) on the basis of information gathered instantaneously on a vehicle (11) side, and a beacon located locally. When passing through a radio wave reception area, a beacon receiver (1) that identifies position information of the reception area from the beacon electric wave and detects a passage timing of the closest position to the transmitting section (10) of the beacon electric wave.
3) and correcting means for correcting the instantaneous vehicle position calculated by the calculating means (12) based on the position information identified by the beacon receiver (13) when the passing timing is detected. (14) In the navigation device with a position correction function having: (15) a reference unit (15) for identifying a closest approach distance to the transmitting unit (10) when passing through the reception area and estimating an error distance of the passing timing. ), And when the difference between the instantaneous vehicle position by the calculating means (12) and the position information by the beacon receiver (13) is smaller than the error distance, the correction means (14) Control means for canceling the correction (16)
And a navigation device with a position correction function. 2. The navigation device with a position correction function according to claim 1, wherein the reference means (15) identifies a traveling direction from a beacon radio wave, and determines the order of the traveling direction.
A reference device for making the error distance different based on the distinction in the reverse direction, wherein the navigation device has a position correction function. 3. A calculating means for calculating the instantaneous position of a running vehicle on the basis of information continuously collected on the vehicle side, and passing through a beacon radio wave reception area located locally. When identifying the position information of the receiving area from the beacon radio wave, and, the beacon receiver to detect the passage timing of the closest position to the transmission unit of the beacon radio wave, when the passage timing is detected, Correction means for correcting the instantaneous vehicle position calculated by the calculation means based on the position information identified by the beacon receiver, a navigation device with a position correction function, wherein a beacon when passing through the reception area A reference unit for identifying a reception state of a radio wave and estimating an error distance of the passing timing; an instantaneous vehicle position by the arithmetic unit; The difference between the position information by Shin machine, wherein when less than the error distance, the correction means according to the corrected position correcting function navigation apparatus characterized by the control means to stop, was provided.