JP2002352375A - Lane marker, lane marker detector and lane marker system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a lane marker, a lane marker detector and a lane marker system for easily acquiring information required for vehicle traffic at a low cost without needing a long coding area on a vehicle passage and without using many frequencies. SOLUTION: This lane marker comprises a receiving antenna (a rod antenna 5), a frequency converting means (a frequency multiplying circuit 6) for converting the frequency of a signal received by the rod antenna 5, a phase changing means (a phase shifter 7) for changing the phase of the signal converted by the frequency multiplying circuit 6, and a transmitting antenna (a disk-like transmitting antenna 8) for transmitting the signal changed in the phase by the phase shifter 7.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a lane marker system for detecting the position of a vehicle on a road.

[0002]

2. Description of the Related Art Heretofore, as a lane marker system that lays a lane marker on a traffic path of a vehicle and detects the position of the vehicle, a lane marker system using magnetism or an electromagnetic wave is known.

In a lane marker system using magnetism, the position of the vehicle is determined by detecting the strength and direction of the magnetic flux of the magnetic marker embedded in the road by a marker detector provided on the vehicle side, In addition, utilizing the fact that the magnet has an N pole and an S pole, binary coding is performed on the signal from the marker to provide road information.

As a lane marker system using an electromagnetic wave, for example, as disclosed in Japanese Patent Application Laid-Open No. 11-339193, an electromagnetic wave reflection type marker in which electromagnetic waves transmitted by a vehicle are embedded in a plurality of rows in the width direction of a road traveling lane. There is known an apparatus in which the electromagnetic wave is detected and reflected, and the reflected electromagnetic wave is received by a marker detector on the vehicle side, and the position of the vehicle is determined based on the electric field intensity distribution of the received electromagnetic wave.

[0005] Regarding the provision of road information in a lane marker system using electromagnetic waves, electromagnetic waves of a plurality of frequencies are transmitted in time series from the lane marker, and each reflected electromagnetic wave is detected on the vehicle side to obtain road information. It is known to provide. It is also known that an IC is mounted on the lane marker side to provide road information.

[0006]

In the marker system using magnetism, however, binary coding is performed to provide road information. However, signals from many lane markers are required to obtain road information. There was a problem that a long coding area on the road was required.

In the marker system using electromagnetic waves, it is necessary to transmit electromagnetic waves of a plurality of frequencies in time series and to detect each of the transmitted electromagnetic waves. There was a disadvantage.

In a lane marker system having an IC mounted on the lane marker side, it is necessary to mount a large number of electronic components on the lane marker. Therefore, there is a problem that the configuration as a lane marker becomes complicated, and a large cost is required for constructing a lane marker system.

The present invention has been conceived in order to solve the above problems, and does not require a long coding area.
It is another object of the present invention to provide a lane marker, a lane marker detector, and a lane marker system for easily and inexpensively providing road information required for vehicle traffic without using a large number of frequencies.

[0010]

According to the present invention, there is provided a lane marker comprising a receiving antenna, frequency converting means for converting the frequency of a signal received by the receiving antenna, and changing the phase of the signal converted by the frequency converting means. And a transmitting antenna for transmitting a signal whose phase has been changed by the phase changing means.

According to this configuration, the lane marker provides information on the presence or absence of the lane marker, and also has a configuration in which the phase of the electromagnetic wave reflected from the lane marker is different. Can be provided.

Further, in the lane marker of the present invention, the reception antenna is constituted by a rod-shaped antenna, the transmission antenna is constituted by a disk-shaped antenna, and the reception antenna is mounted on a disk plane of the transmission antenna. Features.

According to this configuration, since the receiving antenna is a rod-shaped antenna, the receiving sensitivity has directivity, so that unnecessary electromagnetic waves are not received, and the transmitting antenna can efficiently transmit to the lane marker detector. it can.

Further, in the lane marker according to the present invention, the phase changing means is constituted by a difference in a winding direction of a coil of the transmitting antenna.

According to this configuration, a large amount of phase shift can be easily obtained, so that the configuration of the phase changing means is simplified as a whole.

A lane marker detector according to the present invention comprises a transmitting means for transmitting a signal to a lane marker, a receiving means for receiving a signal from the lane marker, and a position for detecting a phase difference between the transmitted signal and the received signal. Phase difference detecting means.

With this configuration, it is possible to acquire information on the presence / absence of a lane marker on a traffic route where the lane marker is installed and the amount of information according to the phase difference between the lane markers.

Further, the lane marker system of the present invention comprises:
A lane marker system including the lane marker according to any one of claims 1 to 3 and the lane marker detector according to claim 4, wherein information on a traffic path is obtained from phase information of a signal transmitted from the lane marker. Characterized in that it comprises information acquisition means for acquiring

With this configuration, the presence / absence of a lane marker on a traffic road and the amount of information corresponding to the phase difference of each lane marker are acquired, and information on the traffic road, such as the current position of the vehicle, the curve degree of the traffic road, etc. Information can be easily obtained.

[0020]

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

(First Embodiment) FIG. 1 shows a first embodiment of the present invention.
It is a perspective view showing the composition of the lane marker which is an embodiment. In FIG. 1, a storage case 9 and a lid 10 hermetically store an antenna, a circuit element and the like to be described later. Rod antenna 5
Is for a received electromagnetic wave (first frequency), and its output signal is output to a frequency multiplying circuit 6 as frequency variable means and multiplied to a second frequency. Frequency multiplier 6
Is input to a phase shifter 7 as a phase changing means, for example, to cause a phase delay. The output signal of the phase shifter 7 is input to a disc-shaped transmitting antenna 8 as a transmitting antenna for the second frequency. Here, the rod-shaped antenna 5 as a receiving antenna is mounted on the disk plane of the disk-shaped transmitting antenna 8.

The phase indication 33 written on the lid 10 describes the phase type of the transmission wave from the lane marker when the lane marker is installed with the lid face up, and here, a phase difference of + 30 ° is generated. This shows that the phase shifter 7 is configured.

FIG. 2 is a diagram showing an example of a circuit configuration from the rod antenna 5 to the transmission antenna 8 in FIG.
In FIG. 2, a receiving antenna unit 1 that receives an electromagnetic wave of a first frequency is, for example, a rod-shaped antenna (bar antenna) formed by winding a coil around a cylindrical ferrite. The receiving antenna unit 1 receives an electromagnetic wave of a first frequency transmitted from a lane marker detector described later and outputs the electromagnetic wave to a frequency multiplying circuit 2. The frequency multiplier 2 receives the received first
Is converted to a second frequency by the frequency multiplier 2 using a diode bridge. The phase shifter 3 includes a resistor and a capacitor, and shifts the phase of the second frequency signal by, for example, 30 °. The transmission antenna unit 4 receives the output signal of the phase shifter 3 and transmits it to the lane marker detector as an electromagnetic wave of the second frequency.

FIG. 3 is a diagram showing the waveform of the electromagnetic wave received by the lane marker and the waveform of the electromagnetic wave transmitted by the lane marker, corresponding to the components of the lane marker. FIG.
In the figure showing the waveform as (b), the horizontal axis represents time, and the vertical axis represents amplitude. 3 (a), the frequency of the first electromagnetic wave received by the rod-shaped antenna 5 shown in FIG.
It is converted to double the frequency. Next, a phase shift of a predetermined amount (for example, 45 ° in FIG. 3) is given in the phase shifter 7. This phase shift amount can be changed to an arbitrary value by changing the circuit constant.

The operation of the lane marker described above will be described below. The lane marker transmits an electromagnetic wave having a phase shift amount given by the phase shifter 7 from the lane marker at a second frequency different from the received electromagnetic wave of the first frequency. Since the frequencies of the reception electromagnetic wave and the transmission electromagnetic wave are different from each other, even when the transmission source (for example, the lane marker detector) transmits the electromagnetic wave of the first frequency to the lane marker, the lane marker has the second frequency different from that frequency. Therefore, the lane marker detector can accurately detect the presence or absence of the lane marker.

When installing the rod-shaped antenna 5, the notation of the rod-shaped antenna 5 and the lid 9 may be used, for example, “installing the rod-shaped antenna 5 in a direction perpendicular to the characters described as the mark on the cover 10 of the housing”. Is set in advance, it becomes easy to set the lane marker detector on the road by aligning the moving direction of the lane marker detector with the setting direction of the rod-shaped antenna 5. Since the rod-shaped antenna 5 has directivity, even if there is a radio wave transmission source in a direction other than the moving direction of the lane marker detector, the lane marker detector can hardly receive it, and the lane marker is less affected by unnecessary electromagnetic waves. It is effective in constructing a marker system.

Further, since the phase of the electromagnetic wave transmitted by the lane marker can be changed by the phase shift amount set in the phase shifter incorporated in the lane marker in advance, even if a plurality of lane markers having the same external configuration are installed, the phase of the Can be identified as a plurality of different lane markers. Therefore, different information according to the phase difference between the lane markers can be provided. Further, it is not necessary to use a long coding area on a vehicle traffic path as in the related art for detecting the position of the vehicle.

(Second Embodiment) FIG. 4 shows a second embodiment of the present invention.
It is a perspective view showing the composition of the lane marker which is an embodiment. In FIG. 4, the storage case 9 includes an installation seat 11, and stores an antenna, a circuit element, and the like described later together with the lid 10. The rod-shaped antenna 5, the frequency multiplier 6, the phase shifter 7, and the disc-shaped transmission antenna 8 are the same as those shown in FIG. Further, the phase display 33 written on the lid 10 describes the phase type of the transmission wave from the lane marker when the lane marker is installed with the lid surface on the upper side.
This shows that the phase shifter 7 is configured to generate a phase difference of + 45 °. Note that the mounting seat 11 is used as a place where holes for mounting screws are formed when a lane marker is mounted on a structure such as the bottom of a manhole or on a road.

FIG. 5 is a diagram showing an example of a circuit configuration from the rod antenna 5 to the transmitting antenna 8 shown in FIG. The antenna unit 1 for receiving the electromagnetic wave of the first frequency, the frequency multiplying circuit 2, the phase shifter 7, and the transmitting antenna unit 4 are shown in FIG.
Is the same as the circuit configuration shown in FIG. The transmitting antenna 34 is similar in appearance to the transmitting antenna 8, but has different winding directions. The transmission antenna 8 is a loop coil formed by winding a coil clockwise in a plane, and the transmission antenna 34 is a loop coil formed by winding a coil counterclockwise.

Hereinafter, the transmitting antenna 8 is referred to as a positive-phase transmitting antenna, and the transmitting antenna 34 is referred to as a negative-phase transmitting antenna. In the marker in which the phase shifter 7 with the phase difference set to 30 ° is combined with the positive phase transmitting antenna 8, the phase difference is 30 °, and when the phase shifter 7 and the opposite phase transmitting antenna 34 with the same setting are combined. , And the phase difference is 210 °. In this way, by combining the phase shifter 7, the positive phase transmission antenna 8, and the opposite phase transmission antenna 34, it is possible to generate a phase type twice as large as the type of the phase shifter having a different phase shift amount. . Alternatively, if the number of phase types is the same, it is possible to reduce the types of phase shifters that need to be adjusted to half as compared with the case where the phase difference is generated only by the phase shifters.

FIG. 6 is a diagram showing the waveform of the electromagnetic wave received by the lane marker and the waveform of the electromagnetic wave transmitted by the lane marker, corresponding to the components of the lane marker. In FIG. 6B showing the waveform, the horizontal axis represents time, and the vertical axis represents amplitude. The frequency of the first electromagnetic wave received by the rod antenna 5 in FIG.
It is converted to twice the frequency. Next, a predetermined amount of phase shift (FIG. 6)
45 °) in the phase shifter 7. This phase shift amount can be changed to an arbitrary value by changing the circuit constant. The phase difference of the electromagnetic wave transmitted from the positive phase transmitting antenna 8 with respect to the output of the phase shifter 7 is 45 ° as compared with the received electromagnetic wave. And the anti-phase transmitting antenna 34
Has a phase difference of 225 °.

The markers according to the second embodiment can be of different types depending on the configuration of the phase shifter 7 and the transmitting antenna, even if the appearance is the same. for that reason,
This is effective in increasing the amount of information received by the marker detector.

FIG. 7 is a perspective view showing the configuration of the anti-phase transmitting antenna 34 shown in FIG. 7, the connection 12 between the frequency multiplier 6 and the anti-phase transmission antenna 34 indicates that the winding direction of the coil of the transmission antenna 34 is opposite to that of the transmission antenna 8 shown in FIG. I have. Changing the winding of the coil in the forward direction and the reverse direction in the transmitting antenna in this manner is one embodiment of the phase changing means in the lane marker of the present invention. In an actual configuration, in addition to the configuration shown in FIG.

(Third Embodiment) FIG. 8 shows a third embodiment of the present invention.
It is a perspective view showing the composition of the lane marker which is an embodiment. 8, the storage case 9 is a first storage case, and the storage case 13 is a second storage case. In the second storage case 13, the lane marker storage items from the rod-shaped antenna 5 to the transmission antenna 8 are aligned and stored inside, and then the positional relationship of the rod-shaped antenna 5 rotated counterclockwise around the axis of the rod-shaped antenna 5 is shown. Is shown. Therefore, the bottom portion 14 of the second storage case 13 is visible in FIG. By describing the phase indicator 15 on the bottom portion 14, the second storage case 13
The phase of the lane marker storage item stored in is displayed. The transmitting antenna of the second storage case 13 shown in FIG.
The transmitting antenna is the same as the anti-phase transmitting antenna 34 shown in FIG. 5, and the phase indicator 15 indicates that the transmitting antenna is different from the positive-phase transmitting antenna.

(Fourth Embodiment) FIG. 9 is a block diagram showing a configuration of an embodiment of a lane marker detector according to the present invention. In FIG. 9, a microprocessor 16 (hereinafter MP)
U) controls the operation of the lane marker detector. The oscillation circuit 18 oscillates the first frequency described above,
The output is transmitted to the transmission amplifier 19 for transmission to the lane marker. The transmission antenna 20 is a substantially annular or substantially rectangular loop antenna.

The receiving antennas 211 to 213 are antennas for receiving the transmission wave of the second frequency from the lane marker described above. The reception amplifiers 221 to 223 are amplifiers for amplifying the reception signal. Detection circuits 231 to 233 detect the amplified signals amplified by the reception amplifiers 221 to 223, and
Output to PU16. In FIG. 9, three receiving circuits are provided, and are arranged, for example, at the left, center, and right of the vehicle.
The phase difference detector 24 detects a phase difference between the transmission electromagnetic wave and the reception electromagnetic wave in the lane marker detector.

Next, the operation of the lane marker detector shown in FIG. 9 will be described. Under the control of the MPU 16, the transmitting antenna 20 converts the above-mentioned electromagnetic wave of the first frequency into a continuous wave and transmits the continuous wave to the lane marker. Also MPU16
Also controls the reception of the electromagnetic wave transmitted from the lane marker as follows. Receiving antennas 211 to 213 are arranged on both sides and the center of the vehicle, and the second
When the vehicle passes near the lane marker, the electromagnetic wave of the second frequency reflected from the lane marker is received and amplified. Detection circuit
The MPU 16 takes in the signals detected by 231 to 233. At that time, compare the receiving sensitivity of the three receiving antennas,
A relative position of the vehicle with respect to the position of the lane marker is detected.

Next, the phase difference detector 24 compares the phases of the transmission electromagnetic wave and the reception electromagnetic wave of the lane marker detector, and the MPU 16 takes in the result. At this time, the lane marker detector can provide the presence or absence of the lane marker based on the phase shift difference of the received wave and the amount of information according to the phase difference for each lane marker.

(Fifth Embodiment) FIG. 10 is a schematic configuration diagram showing a fifth embodiment of the lane marker system of the present invention. The lane marker detector 25 is mounted on a vehicle 26. The lane markers 27, 31, and 32 each include a phase delay circuit such as a phase shifter in each lane marker, the lane marker 27 having no phase delay, the lane marker 31 having a phase delay of 60 °,
The lane marker 32 has a phase delay of 120 °. Each lane marker is installed on the road 28. A first frequency electromagnetic wave signal 29 transmitted from the marker detector 25 and a second frequency electromagnetic wave signal 30 reflected from the marker 27 are illustrated.

The phase difference detector 24 shown in FIG. 9 is installed in the lane marker detector 25, and simultaneously with the reception of the electromagnetic wave signal 29 of the second frequency, the phase difference detector 24 and the transmission wave to the lane markers 27, 31, and 32 are used. The phase difference has been detected. FIG. 11 shows the phase of the electromagnetic wave signal of the first frequency in the lane marker detector 25 (transmitter in the detector) and the phase of the electromagnetic wave signal of the second frequency reflected from the lane markers 27, 31, and 32. I have.

At this time, if the phase delay amount of the lane marker is arbitrarily selected and the phase difference between the transmission wave and the reception wave is detected by the phase difference detector in the lane marker detector, the phase difference is derived from the reception intensity in the lane marker detector. Since it is possible to detect the phase delay amount for each lane marker together with the position information, it is possible to construct a lane marker system using the lane markers installed on the road surface.

FIG. 12 is a diagram showing a configuration of a lane marker system according to one embodiment of the present invention. In FIG. 12, a lane marker 31 with a phase delay of 60 ° is set in front of the left curve of the road 28, and a phase delay of 1 is positioned in front of the right curve of the road.
A 20 ° lane marker 32 is set. A lane marker 27 having no phase delay is provided on the straight road. Since the vehicle 26 can detect the phase corresponding to each of the lane markers,
Knowing the amount of phase change, the current position is just before the right curve,
Alternatively, it is possible to obtain information indicating that the vehicle is near the left curve. Therefore, this lane marker system can be used as an accident prevention support device. As described above, since the frequency conversion means and the phase difference detection means are used in combination, a lane marker system can be constructed without using a large number of frequencies.

Note that, in addition to the above, the configuration can be changed. For example, the lane marker is housed in a non-magnetic case, and various indications or markings are performed on the indication of the phase type of the transmission electromagnetic wave.

The frequency conversion circuit can convert to a frequency other than the frequency doubling. The storage case of the lane marker may be integrally formed, instead of being divided into the main body and the lid.
The location where the phase display is performed is not limited to the upper part of the lid, and a side surface or the like can be used.

Further, when a plurality of lane markers are set in the width direction on the road, the position information of the vehicle corresponding to each lane marker can be provided, so that a warning is issued when the vehicle advances beyond a predetermined width. Control can be performed to prevent lane departure. The lane keeping of the vehicle running on the road can be performed in a similar manner.

[0046]

As described above, according to the present invention, a vehicle provided with a lane marker detector is provided by providing the lane marker using electromagnetic waves with phase change means and the lane marker detector with phase difference detecting means. On the side, the amount of information corresponding to the plurality of phase differences can be acquired simultaneously with the position detection on the traveling road. Therefore, road information necessary for vehicle traffic can be easily provided at low cost.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a configuration of a lane marker according to a first embodiment of the present invention;

FIG. 2 is a diagram illustrating an example of a circuit configuration of a lane marker illustrated in FIG. 1;

FIG. 3 is a diagram showing a waveform of an electromagnetic wave received by the lane marker shown in FIG. 1 and a waveform of an electromagnetic wave to be transmitted, corresponding to the components of the lane marker;

FIG. 4 is a perspective view showing a configuration of a lane marker according to a second embodiment of the present invention;

FIG. 5 is a diagram showing an example of a circuit configuration of the lane marker shown in FIG. 4;

FIG. 6 is a diagram showing a waveform of an electromagnetic wave received by the lane marker shown in FIG. 4 and a waveform of an electromagnetic wave to be transmitted, corresponding to the components of the lane marker;

FIG. 7 is a perspective view showing the configuration of the anti-phase transmitting antenna shown in FIG. 5;

FIG. 8 is a perspective view showing a configuration of a lane marker according to a third embodiment of the present invention;

FIG. 9 is a block diagram showing a configuration of an embodiment of a lane marker detector according to the present invention;

FIG. 10 is a block diagram showing a configuration of an embodiment of a lane marker system according to the present invention;

FIG. 11 is a diagram for comparing and explaining the phase of an electromagnetic wave signal in the lane marker detector shown in FIG. 10;

FIG. 12 is a diagram showing a configuration example of an embodiment of a lane marker system of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Receiving antenna part 2 Frequency multiplying circuit 3 Phase shifter 4 Transmitting antenna part 5 Rod antenna 6 Frequency conversion means (frequency multiplying circuit) 7 Phase shifter 8 Transmitting antenna 9 Storage case 10 Lid 11 Mounting base of storage case 12 Phase shifter Connection between the antenna and the transmission antenna 13 Second storage case 14 Bottom part of the second storage case 15 Bottom phase display 16 MPU 18 Oscillation circuit 19 Transmit amplifier 20 Transmit antenna 211-213 Receive antenna 221-223 Receive amplifier 231-233 Detection circuit 24 Phase difference detector 25 Lane marker detector 26 Vehicle 27 Lane marker 28 Road 29 First frequency signal 30 Second frequency signal 31 Lane marker (phase delay 60 °) 32 Lane marker (phase delay 120 °) 33 Phase display 34 Reverse phase transmission antenna

 ──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Norihiko Tanji 4-3-1 Tsunashima Higashi, Kohoku-ku, Yokohama-shi, Kanagawa Prefecture Inside Matsushita Communication Industrial Co., Ltd. (72) Satoru Handa Tsunashima-Higashi, Kohoku-ku, Yokohama, Kanagawa 4-3-1, Matsushita Communication Industrial Co., Ltd. F-term (reference) 5H180 AA01 BB04 BB06 CC12 CC24 5K067 AA35 AA41 BB21 BB41 BB43 EE02 EE13 FF02 FF03 KK01 KK17

Claims (5)

[Claims] 1. A receiving antenna, frequency converting means for converting the frequency of a signal received by the receiving antenna, phase changing means for changing the phase of the signal converted by the frequency converting means, and the phase changing means And a transmission antenna for transmitting a signal whose phase has been changed by the lane marker. 2. The receiving antenna comprises a rod-shaped antenna, the transmitting antenna comprises a disc-shaped antenna,
The lane marker according to claim 1, wherein the receiving antenna is mounted on a disk plane of the transmitting antenna. 3. The lane marker according to claim 1, wherein the phase changing unit is configured by a difference in a winding direction of a coil of the transmitting antenna. 4. A transmitting means for transmitting a signal to a lane marker, a receiving means for receiving a signal from the lane marker, and a phase difference detecting means for detecting a phase difference between the transmitted signal and the received signal. A lane marker detector. 5. A lane marker system including the lane marker according to any one of claims 1 to 3 and the lane marker detector according to claim 4, wherein phase information of a signal transmitted from the lane marker is provided. A lane marker system, comprising: information acquisition means for acquiring information on a traffic route from a vehicle.