JPH0684095A - Traveling direction discrimination system for mobile object - Google Patents

Abstract

PURPOSE:To accurately discriminate a traveling direction and to prevent mis- judgement by analyzing traveling direction signal information by a specific method for respective plural bytes constituting data. CONSTITUTION:When a mobile object mounted with a receiver progresses in a forward direction and passes near a radio transmitter, the level of AM1 reproducing signals is lowered, the data of [0] are inputted from a first shift register SR-1 and the inverted data of [1] are inputted from a second shift register SR-2 so that the AM1 reproducing signals are discriminated as receivable. In this case, at second AND 46, since the inverted data of [1] from the first shift register SR-1 are inputted and the data of [0] are inputted from the second shift register SR-2, AM2 reproducing signals are discriminated as inreceivable. Thus, the generation of the mis-judgement under weak electric field or the like can be prevented.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mobile body provided with information from a wireless transmitter installed on a road, which can improve the reliability of identifying the traveling direction of the mobile body from the obtained information. It is an object of the present invention to provide a traveling direction identification circuit of the.

[0002]

2. Description of the Related Art Conventionally, as a technique in such a field,
Road-to-vehicle communication is performed between a wireless transmitter (beacon) installed at a predetermined distance on the road and an in-vehicle device, and the position of a passing point, the shape of an intersection, destination guidance, or change is performed using this communication means. There is one that transmits traffic information to a navigation system.

FIG. 5 is a diagram showing an outline of a road-vehicle communication system of the mobile unit 31. As shown in the figure, a wireless transmitter 32 (that is, a mini transmitter station) on the road provides various kinds of information to a receiver of a vehicle facing the road on the road. When the information provided by the wireless transmitter 32 to the vehicle 1 depends on the traveling direction of the vehicle (for example, destination guidance, road shape, road congestion, etc.), the wireless transmitter 32 adds the data information to the data information. Information about the direction of travel must be included and transmitted so that only vehicles traveling in the forward direction can receive the data information and vehicles in the opposite direction do not process the information.

Therefore, for example, from the radio transmitter 32, as the traveling direction information added to the data information, for the forward moving body 31, signal information indicating the forward direction from the antenna, for example, a predetermined frequency is transmitted. A square wave AM1 that has the same frequency as that of the forward direction square wave AM1 but is 180 degrees out of phase with the forward direction square wave AM1 is transmitted as signal information indicating the opposite direction to the moving body 31 in the opposite direction. AM2 is transmitted.

FIG. 6 is a diagram showing an example of signals of predetermined data information and traveling direction information provided from the wireless transmitter of FIG. As shown in the figure, for example, data irrelevant to the traveling direction is transmitted by frequency modulation (FSK) or phase modulation (PSK) of a digital signal, and the data indicating the traveling direction is applied to the forward and reverse directions of the vehicle. Data AM1 and AM2 which are AM-modulated (ASK) with square waves having mutually opposite phases
Will be sent. The modulation data AM1 and AM2 are synchronized with the frequency modulation data and the like. In the vehicle, when the AM data reception direction changes from AM1 to AM2, the traveling direction is determined to be forward, and when the AM data reception direction is changed from AM2 to AM1, the traveling direction is determined to be reverse.

FIG. 7 is a diagram showing a circuit for identifying a conventional traveling direction, and FIG. 8 is a diagram showing a timing chart of the operation of the traveling direction identifying circuit of FIG. The traveling direction identification circuit shown in FIG. 7 is an AM signal “1” reproduced by the vehicle receiver.
Alternatively, the logical sum of the data stored in the shift register 100 and the shift register 100 that sequentially stores "0" with a reproduction clock described later is calculated, and if all the stored data is "1", it is determined that the AM1 signal has been received. And a second AND circuit 102 for judging that the AM2 signal has been received if all the data are "0".

As shown in FIG. 8, the data from the radio transmitter and the reproduction AM1 (solid line) and the reproduction AM2 (dotted line) are synchronized as described above, but the receiver reproduces the data in synchronization with the data. Generates clock 1 and reproduces clock 1
A reproduced clock 2 whose phase is shifted by π / 2 is generated. At the rising edge of the reproduction clock 2, the reproduction AM signal is taken into the shift register, and if the first AND circuit 101 outputs "1" for all bits,
It is determined to be AM1 reception, and if the second AND circuit 102 outputs "0" in all bits, it is determined to be AM2 reception. That is, one of the first AND circuit 101 and the second AND circuit 102 can receive. If "1" and "0" data are mixed in the shift register, A
It is determined that M cannot be received. If the AM reception is possible, the current processing is continued, but if the AM reception is impossible for a certain period of time, another backup processing is performed.

For example, if a vehicle equipped with a receiver advances from the forward direction, the first AND circuit 101 is
It is determined that M1 reception is possible, and the second AND circuit 102 determines that AM1 reception is impossible. When the vehicle equipped with the receiver passes through the wireless transmitter, the first AND circuit 101 determines that AM2 cannot be received, which is in the opposite phase to AM1, and the second AND circuit 102 determines that AM2 is available. I do.

However, in the conventional traveling direction identification circuit, when the received electric field is weak, the level of the AM reproduction signal is lowered and the following problems occur. That is, FIG. 9 is a diagram showing the level drop of the AM reproduction signal when the received electric field is weak. As shown in the figure, when the level of the AM1 reproduction signal is low, the first AND circuit 101 determines that the AM1 reproduction signal cannot be received, but the second AND circuit 102 can receive the AM2 reproduction signal. It is determined that the AM2 reproduction signal is received normally when the signal passes through the wireless transmitter. Therefore, the inversion from the AM1 reproduction signal to the AM2 reproduction signal cannot be detected by the second AND circuit 102, and the vehicle travels after all. The direction cannot be determined. Further, since the inversion of the AM1 reproduction signal and the AM2 reproduction signal cannot be observed, the information at the time of passing the beacon cannot be obtained. In this way, if the necessary data on the traveling direction cannot be obtained, appropriate signal processing cannot be performed, so it is necessary to quickly move to another backup signal processing, but at present it cannot be determined. The same applies when the level of the AM2 reproduction signal is low. A similar problem occurs even when the AM reproduction signal is stuck at a high level due to a failure of the receiver that extracts the AM reproduction signal.

That is, in the conventional traveling direction determination system for a mobile body, when the electric field strength is sufficient, noise is not generated, and all signal information is normally received, the system operates without any problem. However, if noise occurs, a circuit failure occurs, or if a large truck or bus happens to run side by side, a sufficient electric field cannot be received from the transmitter, resulting in an error. There is a risk of being judged.

[0011]

SUMMARY OF THE INVENTION In view of the above problems, the present invention provides a traveling direction identification system for a moving body, which is capable of accurately identifying the traveling direction for smooth signal processing and preventing erroneous determination. With the goal.

[0012]

In order to achieve the above-mentioned object, the present invention adopts the technical constitution as described below. That is, the wireless transmitter installed on the road, which simultaneously transmits the data regarding the road information and the traveling direction signal information for determining the traveling direction of the moving body in synchronization with the data, and which is provided on the moving body side, A traveling direction determination circuit that receives and arithmetically processes the data and the traveling direction determination signal information, and the traveling direction determination circuit uses the traveling direction determination signal information received from the wireless transmitter. A traveling direction determining means for determining a traveling direction of the moving body, and a determining operation executing means for repeatedly performing the traveling direction determining operation of the moving body by the traveling direction determining means for each of a plurality of bytes forming the one data. A forward integration means and a backward integration means for individually integrating the plurality of traveling direction determination results obtained for each of a plurality of bytes forming the one data for each of the forward direction and the backward direction, A majority decision means for comparing the count value obtained by the direction integrating means with the count value obtained by the backward integrating means to select the one having the larger count value, whether the received data is normal data It is composed of a data quality judging means for judging whether the data is good or bad, and a means for judging that the judgment result of the majority decision means is valid when the data quality judging means judges that the received data is normal. It is a traveling direction determination system of a mobile body.

[0013]

According to the traveling direction identification system for a moving body of the present invention, first, the traveling direction determination of the moving body is made up of the received data of a predetermined length and the traveling direction determination signal.
With respect to one data, the traveling direction signal information is analyzed for each of a plurality of bytes forming the data by the following method.

That is, the clock generating means forms the regenerated clock 2 and the regenerated clock 3 which are out of phase with the regenerated clock 2 with a phase difference of π / 2 in the same cycle as the square wave indicating the traveling direction. The square wave indicating the traveling direction is fetched as bit data by the reproduction clock 2 and shifted by the first shift register, and the square wave indicating the traveling direction is changed by the reproduction clock 3 by the second shift register. A logical operation is performed on each bit data that is fetched and shifted as bit data and that is fetched in the first shift register by the first logical operation means and each bit data that is fetched in the second shift register and inverted. A logical product is obtained, and the first shift register is operated by the second logical operation means. The captured logical operation for each bit data taken into inverted each bit data and the second shift register which, for example, a logical product is taken.

Next, the above operation is performed for each bite to judge the traveling direction of the moving body in units of bytes, and the traveling direction of the moving body at that time point is the forward direction or the reverse direction. That data is individually added to the forward integration means and the backward integration means. After that, when the above-mentioned arithmetic operation is completed for all the bytes, the count values accumulated for the forward direction integrating means and the backward direction integrating means are compared for each byte, and the larger one is traveled. The direction is determined to be the traveling direction of the moving body at the time of receiving the data.

Therefore, even if a different direction is determined in several bytes due to some noise or the presence of an obstacle during the reception of 1 data, the count value as a whole. Since the direction with the most traffic is the traveling direction of the moving body at that time, there is no risk of misjudgment due to the occurrence of noise or the presence of obstacles.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A concrete example of a traveling direction determining system for a moving body according to the present invention will be described below in detail with reference to the drawings. FIG. 1 is a block diagram showing the configuration of a specific example of a moving body traveling direction determination system 200 according to the present invention.

In FIG. 1, a wireless transmitter 32 installed on a road, which simultaneously transmits data relating to road information and traveling direction signal information for determining the traveling direction of a moving body in synchronization with the data. And a traveling direction determination circuit 33 that is provided on the side of the moving body 31 and that receives the data and the traveling direction determination signal information and performs arithmetic processing on the data and the traveling direction determination circuit 33. From the traveling direction determination signal information received from the wireless transmitter 32, the detection means 34 for detecting the traveling direction signal information, the traveling direction determination means 44 for determining the traveling direction of the mobile body 31, and the traveling direction determination means 44. The moving direction determination operation of the moving body 31
Judgment operation executing means 36 for repeatedly executing every plurality of bytes forming one data, and the plurality of traveling direction judgment results obtained for each plurality of bytes forming one data according to forward direction and reverse direction. The forward integration means 37 and the backward integration means 38 for integrating individually, the count value obtained by the forward integration means 37 and the count value obtained by the backward integration means 38 are compared, and the count value is large. Majority decision means 39 for selecting one, means 40 for detecting the data from the received information, data pass / fail judgment means 41 for determining whether the received data is normal data,
And the traveling direction determining means 42 which determines that the judgment result of the majority decision judging means 39 is valid when the data quality judging means 41 judges that the received data is normal. A direction determination system is shown.

Further, in the traveling direction judging system 200 for a moving body according to the present invention shown in FIG. 1, in response to the output of the traveling direction deciding means 42, the decided traveling of the moving body 31 at present. The direction may be displayed on the appropriate display means 43, and the predetermined road information or other information indicated by the data may be simultaneously displayed on the display means 43.

The data relating to the road information used in the traveling direction determination system of the mobile body according to the present invention and the signal information for determining the traveling direction of the mobile body 31 output in synchronization with the data are both. For example, it may be one in which an AM wave of 1 KHz is modulated and superimposed on an appropriate carrier wave having a high frequency of 2 GHz, and the signal information of both may be supplied individually, or It may be supplied integrally as one data.

In particular, it is desirable that the road information data used in the present invention can be converted into digital values later. Further, the traveling direction determination signal information according to the present invention is a square wave as shown in FIG. 6, and is different from the square wave AM1 indicating the forward direction and the square wave AM2 indicating the reverse direction. It is preferable that they have the same frequency and are 180 degrees out of phase with each other.

The traveling direction judging means 44 used in the traveling direction judging system for the moving body in the present invention is shown in FIG.
As shown in FIG. 2, detection is performed to detect data including road information and the traveling direction signal information from the received signal information from the wireless transmitter 32 and the like to generate predetermined data information and a reproduction square wave. A circuit 34, a circuit 35-1 for generating a first reproduction clock signal RC-1 synchronized with the reproduction square wave, and .pi. / 2 at the same cycle as the first reproduction clock signal RC-1.
A clock generation circuit 3 for forming a second reproduction clock signal RC-2 and a third reproduction clock signal RC-3 having a phase opposite to that of the second reproduction clock signal RC-2 which are out of phase with each other.
5-2 and 35-3, a reproduction square wave AM1 indicating one direction of the reproduction square wave indicating the traveling direction, for example, a reproduction square wave AM1 indicating the forward direction, is fetched as bit data by the second reproduction clock signal RC-2. Shift register SR-1 of the second reproduction clock signal RC-2 and the other reproduction square wave of the reproduction square wave indicating the traveling direction, for example, the reproduction square wave AM2 indicating the opposite direction. 3 reproduction clock signal RC-
A register means 47 composed of a second shift register SR-2 which is taken in as bit data by 3 and a plurality of bytes which compose one data including the traveling direction signal information, in a predetermined byte unit, A first logical operation circuit 45 for performing a logical operation of each bit data fetched in the first shift register SR-1 and each bit data fetched in the second shift register SR-2 and inverted, and the first logical operation circuit 45. A second logical operation circuit 46 for performing a logical operation on each bit data fetched and inverted by the first shift register SR-1 and each bit data fetched by the second shift register SR-2. Is desirable.

In the traveling direction determination circuit 33 according to the present invention, the traveling direction of the moving body 31 is determined by the output of the first logical operation circuit 45 and the output of the second logical operation circuit 46. The traveling direction of the mobile body is determined from the combination. Hereinafter, a specific example of the moving body traveling direction determination method according to the present invention will be described.

The method for determining the traveling direction of the moving body 31 in the conventional traveling direction determining system for a moving body is as described above. In such a method, an erroneous determination is made especially when the signal output is small, that is, the electric field strength is small. Or the moving body 3
Since there is a problem that the traveling direction of No. 1 cannot be determined, in the present invention, in order to solve such a problem, as described above, as a sampling signal, a reproduction square wave signal is used as a sampling signal. A second reproduction clock signal RC-2 that is 90 degrees out of phase with the synchronized first reproduction clock signal RC-1 and a third reproduction that is an inverted signal of the second reproduction clock signal RC-2. Two kinds of clock signals RC-3 are prepared, and a reproduction square wave AM1 representing, for example, a forward direction is sampled by the leading edge of the second reproduction clock signal RC-2 and the third reproduction clock signal RC-3 is sampled.
With the leading edge of the reproduced clock signal RC-3, the reproduced square wave AM2 representing the reverse direction is sampled.

Then, sampling is performed in a predetermined sampling period, and the second reproduction clock signal R
The information sampled by C-2 is, for example, the reproduction square wave AM1 indicating the forward direction is the first shift register S
The information once stored in R-1 and the information sampled by the third reproduction clock signal RC-3, for example, a reproduction square wave AM2 indicating the reverse direction, is temporarily stored in the second shift register SR-2. To be done.

A shift register circuit 47 including the shift registers SR-1 and SR-2 and the logic circuits 45 and 4 described above.
An example of the traveling determination operation of the moving body 31 and the circuit for executing the traveling determination operation according to 6 will be described with reference to FIGS. 2 to 4. FIG. 2 is a diagram showing a configuration of a specific example of the traveling direction identification circuit 33 of the moving body 31 according to the embodiment of the present invention.

FIG. 3 is a diagram showing a timing chart in the traveling direction identification circuit of FIG. Moving body 3 shown in FIG.
The traveling direction identification circuit 1 detects the start position of the data from the reception detection circuit 34 that receives the data transmitted from the wireless transmitter 32 on the road via the antenna 1 and will be described later in synchronization with this start position. The clock generating means 35 is provided for supplying a clock signal RC to fetch and shift data in the shift register SR.

As shown in FIG. 2, in the data provided from the radio transmitter 32, data irrelevant to the traveling direction is digital signal frequency modulation (FSK) or phase modulation (PSK).
The data indicating the traveling direction, which is transmitted by K), is a square wave having mutually opposite phases with respect to the forward and reverse directions of the vehicle.
In some cases, modulated (ASK) data AM1 and AM2 are transmitted.

The modulation data AM1 and AM2 are synchronized with the frequency modulation data and the like. The clock generation means 35 synchronizes with the start position of the data irrelevant to the traveling direction by the detection signal of the start position of the data, and as shown in FIG. The first reproduction clock RC-1 is generated, and the second reproduction clock RC-2 which is shifted by π / 2 from the first reproduction clock RC-1 is generated.

Further, a traveling direction judging circuit 33 for the moving body 31.
Means for receiving the data AM from the receiver 2 in the clock generating means 3
The first shift register SR-1 for fetching data at the rising edge of the second reproduction clock RC-2 and shifting the fetched data is provided. Further, the traveling direction judging circuit 44 of the moving body 31 has the clock generating means 35 as shown in FIG.
The second shift register SR-2 for fetching the data AM2 from the detection means 34 at the rising edge of the third regeneration clock RC-3 obtained by inverting the second regeneration clock RC-2 of the inverter 8 and shifting the fetched data. To have.

A traveling direction determination circuit 33 for the mobile unit 31 is also provided.
Is the logical product of each output of the first shift register SR-1 and each inverted output of the second shift register SR-2,
The AM2 signal is obtained by taking the logical product of the first AND means 45 for judging the presence or absence of the reception of the AM1 reproduction signal, each inverted output of the first shift register SR-1 and each output of the second shift register SR-2. Second AND means 46 for judging the presence or absence of reception of

For example, in FIG. 5, when the mobile unit 31 equipped with the receiver advances in the forward direction and passes through the vicinity of the radio transmitter 32, the level of the AM1 reproduction signal is lowered and the first logical product is obtained. Since the data of "0" is input to the means 45 from the first shift register SR-1 and the inverted data of "1" is input from the second shift register SR-2, the AM1 reproduction signal cannot be received. To judge. In this case, the second AND means 46 receives the inverted “1” data from the first shift register SR-1 and outputs the second data.
Since the data "0" is input from the shift register SR-2, it is determined that the AM2 reproduction signal cannot be received. Therefore, when the first logical product means 45 cannot receive the AM1 reproduction signal, the second logical product means 46 can also determine that the signal cannot be received.

When the mobile unit 31 equipped with the receiver advances from the opposite direction and passes through the vicinity of the radio transmitter 32, the level of the AM2 reproduction signal is lowered and the same arithmetic processing as above is executed. It Although the logical product is used as the logical operation in this example, a method of performing another logical operation is also conceivable.

On the other hand, in the case of a failure in which the mobile body 31 equipped with the receiver advances in the forward direction and the level of the AM1 reproduction signal sticks to the “H” level, the first AND means 45 is
Since "1" data is input from the first shift register SR-1 and inverted "0" data is input from the second shift register SR-2, it is determined that the AM1 reproduction signal cannot be received. In this case, the second AND means 46 receives the inverted “0” data from the first shift register SR-1, and inputs the second shift register SR-
Since the data of "1" is input from 2, it is determined that the AM1 reproduction signal cannot be received. Therefore, according to this embodiment,
It is possible to prevent erroneous determination from occurring under a weak electric field.

FIG. 4 is a diagram showing a specific example of the circuit configuration of the traveling direction determination circuit 33 of FIG. In the specific example shown in this figure,
When AM modulation is performed with a square wave of 1 KHz,
The oscillator 30 of 8.192 MHz is used as the clock generation means 35, and the HC 393 is used as a timing generation counter for generating the first reproduction clock RC-1 and the second reproduction clock RC-2 based on this clock signal. To do.

The third reproduction clock signal RC-3 is
It can be obtained by inverting the output from the HC 393 using the inverter circuit 8. Further, the shift register HC164 is used as the first shift register SR-1 and the second shift register SR-2. In the embodiment of the present invention described above, the logical product of the plurality of bits input at a predetermined time of the input data is ANDed to judge the AM1 reproduction rectangle. If the output of the first logical operation circuit 45 for sampling the wave is at “H” level and the output of the second logical operation circuit 46 for sampling the AM2 reproducing square wave is at “L” level, The traveling direction of the moving body 31 at that time is
The output of the first logical operation circuit 45 for sampling the AM1 reproduction square wave is "L" level, and conversely, the second logical operation for sampling the AM2 reproduction square wave is determined. When the output of the circuit 46 is at the “H” level, the traveling direction of the moving body 31 at that time is
It is determined to be in the opposite direction.

In this determination, noise is generated in one or a plurality of bits due to a temporary factor, or a large vehicle temporarily runs in parallel, so that the traveling direction of the moving body 31 cannot be determined. There is a risk that it will be possible or that the wrong direction of travel will be determined. Therefore, in the traveling direction determination system for a moving body according to the present invention, in order to further improve the above-described specific example, a majority decision method is introduced in the traveling direction determination operation execution step, and it is caused by a temporary factor. Even when the traveling direction of the moving body 31 cannot be determined or an incorrect traveling direction is determined, a plurality of traveling direction determination operations are repeated to obtain a plurality of traveling direction determination results, From the result, the majority direction is used to determine the traveling direction of the moving body 31 at that time.

Specifically, when one predetermined data as shown in FIG. 3 is received, if one frame of the data is composed of, for example, 124 bytes, (1 It is assumed that the byte is, for example, 8 bits.
The judgment operation is repeated 24 times. When the conclusion is determined to be the forward direction at the time of executing the running direction determining operation for each byte, the count value of the forward direction integrating means 37 is incremented by 1 and integrated, and the conclusion is the reverse direction. If it is determined, the count value of the backward integration means 38 is incremented by 1 and integrated.

In the above specific example, an example in which the running direction determination operation is repeated 124 times has been shown, but the number of times of repetition is not particularly limited, and may be appropriately changed according to the length of data. It is possible. That is, in this specific example, it is preferable that a control circuit 36 is provided for executing the operation of repeating the above-described determination operation for each byte of the predetermined received data. It is preferable to have a means for detecting the first data position and the last data position of each byte in the received data, and a detection means for detecting the end of the data.

Then, for all the bytes of the data, when the traveling direction determining operation is completed, the count values of the forward direction integrating means 37 and the backward direction integrating means 38 are compared, and by majority decision, The one with the larger count value is determined as the traveling direction of the moving body 31. However,
Even in such operations, the data itself may be incorrect or all the data may not be received due to low electric field strength, circuit failure, communication system trouble, etc. It is meaningless to determine the direction.

Therefore, in this example, the step of determining whether or not the received data is normally received is also used. If the data is not normally received, the above-mentioned steps are performed. The conclusion itself obtained by the traveling direction determination operation is invalidated, and the output of the result is stopped. The means for judging the quality of the data reception state according to the present invention measures the electric field strength in the data signal received by the mobile body 31 from the wireless transmitter 32, and the result is equal to or higher than a predetermined electric field strength. The data signal transmitted by the wireless transmitter 32 may be added with a predetermined specific signal for judging whether the data is good or bad. When a signal is received, a circuit 41 is provided which compares the received specific signal with the transmitted specific signal and determines that the received data signal is normal when the two match. You can

That is, the structure of the data output from the radio transmitter 32 is, for example, as shown in FIG. 3 (B) for one frame, from the left, the data including the synchronization check signal portion D1 and the predetermined information. And a data part D2 and a data quality judgment check signal part D3.
The data quality judgment check signal section D3 is, for example, a CRC.
It may be one that employs a check system.

Thus, for example, the CR of the received data
It is possible to compare the C data with the CRC data on the transmitting side to determine whether the received data is normal. Next, an operation procedure of the traveling direction determination system for the moving body according to the present invention will be described with reference to the flowchart of FIG. FIG. 10 shows a wireless transmitter 32 installed on a road, which simultaneously transmits data regarding road information and traveling direction signal information for determining the traveling direction of the moving body 31 in synchronization with the data, and the moving body. In the traveling direction determination system for a moving body according to the present invention, which is provided on the side of 31 and includes a traveling direction determination circuit 33 that receives and arithmetically processes the data and the traveling direction determination signal information, After that, in step (1), the mobile body 31 receives the predetermined data information and the traveling direction signal information from the wireless transmitter 32.

Then, the traveling direction of the moving body 31 is determined from the received traveling direction determination signal information in the traveling direction determination circuit 33 in units of bytes forming the data. ), It is determined whether or not the traveling direction determination result in the one byte is forward, and if YES, the process proceeds to step (3), and the count value of the forward integration means 37. Is incremented by 1 and if NO in step (2), the process proceeds to step (4), where it is determined whether or not the traveling direction determination result in the bite is the reverse direction, and YES. If so, the process proceeds to step (5) to set the count value of the backward integration means 38 to 1
If it is NO in step (4), the traveling direction of the moving body 31 cannot be determined when the byte is received. Proceed to step (6) without performing integration.
(That is, in this case, it is not included in the above-mentioned majority decision data.) On the other hand, in step (6), it is determined whether or not the CRC code data in the received data is received. , NO, the process returns to step (1) and the above steps are repeated, but if YES, the process proceeds to step (7) to judge whether the data is good or bad.
According to 1, whether or not the received data is normally received is determined using the CRC code data, and if the CRC code data has an error, that is, if the data is not normally received, , The traveling direction determination process for one byte that is currently processing the data is invalidated, and the operation for the byte is interrupted at that time.

Therefore, the process immediately proceeds to step (11), resets the values of the counters of the forward direction integrating means and the backward direction integrating means, returns to step (1), and waits for reception of the next byte. On the other hand, if NO in step (7), the process proceeds to step (8), in which the majority determination means 39 determines which of the counter value of the forward direction integration means and the counter value of the reverse direction integration means is larger. A majority decision is made, for example, it is judged whether or not the counter value of the forward direction integrating means is larger than the counter value of the backward direction integrating means, and if YES, the process proceeds to step (9), where the current value of the moving body 31 is present. It is concluded that the traveling direction of is the forward direction, the process proceeds to step (12) to display the result on an appropriate display means,
The data such as the received road information is also displayed, and at the same time, the value of the counter of the forward integration means is reset in step (11).

If NO in step (8), the process proceeds to step (10), and it is concluded that the current traveling direction of the moving body 31 is the opposite direction, and step (1)
Proceeding to 1), the value of the counter of the forward integration means is reset. Incidentally, in step (10), the traveling direction of the moving body 31 may be displayed on an appropriate display means, but the data itself is often unnecessary data, so positively , That information is not displayed.

That is, the operation procedure in the traveling direction judging system for the moving body according to the present invention is summarized as follows. That is, the first step of determining the traveling direction of the moving body in units of bytes forming the data from the traveling direction determination signal information received from the wireless transmitter, and a plurality of data forming the one data. A second step of repeatedly executing the above determination operation for each byte, and individually integrating the plurality of traveling direction determination results obtained for each of the plurality of bytes forming the one data in the forward direction and the reverse direction. The third step of storing in the forward integration means and the backward integration means, after the above operation is completed for all of the plurality of bytes forming the one data, the forward integration means and the reverse integration means The fourth step of comparing the integrated count values stored in the respective direction integrating means by the majority decision and selecting the one with the larger count value, the data received by the data quality determining means is normal data. Or not The fifth step of judging whether the received data is normal, the sixth step of judging that the judgment result of the majority judgment means is valid, and the majority judgment means. And a seventh step of displaying the judgment result of.

[0048]

As described above, according to the present invention, the regenerated clock 2 which is out of phase with π / 2 in the same cycle as the square wave indicating the traveling direction, and the regenerated clock having a phase opposite to that of the regenerated clock 2. 3, the square waves indicating the traveling direction are respectively fetched into the shift register and shifted, and logical operations are performed on each bit data fetched in one shift register and each bit data fetched in the other shift register and inverted. Therefore, since the logical operation is performed on each bit data that is taken in and inverted by one shift register and each bit data that is taken in by the other shift register, the waveform of the signal indicating the traveling direction accurately represents a square wave. If it cannot be received, bit data of "1" and "0" are mixed in both shift registers, so both are received. It will be able to determine the possible, thereby preventing an erroneous determination of the direction of travel.

[Brief description of drawings]

FIG. 1 is a block diagram illustrating a traveling direction determination system for a moving body according to an exemplary embodiment of the present invention.

FIG. 2 is a block diagram illustrating a configuration example of a traveling direction determination circuit in a traveling direction determination system for a mobile body according to the present invention.

FIG. 3 is a diagram showing an example of the structure of data and traveling direction determination signal information used in the present invention.

FIG. 4 is a diagram showing a specific example of a traveling direction determination circuit used in the present invention.

FIG. 5 is a schematic diagram of a road-vehicle communication system for a mobile body.

FIG. 6 is a diagram showing data provided from a conventional wireless transmitter.

FIG. 7 is a diagram showing an example of a conventional circuit for identifying a traveling direction.

FIG. 8 is a diagram showing a timing chart of the operation of a conventional traveling direction identification circuit.

FIG. 9 is a diagram showing a decrease in level of an AM reproduction signal when a reception electric field is weak.

FIG. 10 is a flowchart illustrating an operating procedure of the traveling direction determination system for a mobile body according to the present invention.

[Explanation of symbols]

 31 ... Moving body 32 ... Radio transmitter 33 ... Running direction determination circuit 34 ... Reception detection means 35 ... Regenerated clock generation means 36 ... Judgment operation execution control means 37 ... Forward integration means 38 ... Reverse integration means 39 ... Majority judgment means 40 ... Data reproducing means 41 ... Data quality judging means 42 ... Running direction determining means 43 ... Display means 44 ... Running direction determining means 45 ... First logical operation circuit 46 ... Second logical operation circuit 200 ... moving direction of moving body Judgment system

Claims (10)

[Claims] 1. A wireless transmitter installed on a road, which simultaneously transmits data related to road information and traveling direction signal information for determining a traveling direction of a mobile body in synchronization with the data, and a radio transmitter on the side of the mobile body. And a traveling direction determination circuit that receives and processes the data and the traveling direction determination signal information. The traveling direction determination circuit is for traveling direction determination received from the wireless transmitter. A traveling direction determination unit that determines the traveling direction of the moving body from the signal information, and a determination that the traveling direction determination operation of the moving body by the traveling direction determination unit is repeatedly executed for each of a plurality of bytes forming the one data. Operation executing means, forward accumulating means and backward accumulating means for individually accumulating the plurality of traveling direction determination results obtained for each of a plurality of bytes forming the one data for each of forward and backward directions. A majority decision means for comparing the count value obtained by the forward integration means with the count value obtained by the backward integration means to select the one having the larger count value, the received data being normal. From the data quality determining means for determining whether or not it is data, and the means for determining the determination result of the majority determination means as valid when the data quality determining means determines that the received data is normal. A traveling direction determination system for a moving body, which is configured. 2. The data quality determining means measures the electric field strength in the data signal received by the mobile unit from the wireless transmitter, and judges whether or not the result is equal to or higher than a predetermined electric field strength. The traveling direction determination system for a mobile body according to claim 1, wherein 3. The data quality determination means adds a predetermined specific signal for data quality determination to the data signal transmitted by the wireless transmitter, and the data signal is received when the data signal is received. 2. The movement according to claim 1, further comprising a circuit that compares the specific signal with the transmitted specific signal and determines that the received data signal is normal when the two match. Body running direction determination system. 4. The signal information for determining the traveling direction of the moving body in synchronization with the data relating to the road information is a square wave superimposed on an appropriate carrier wave, and the square wave indicating the forward direction and the reverse direction. 2. The traveling direction determination system for a mobile body according to claim 1, wherein the square waves indicating the same have the same cycle and the phases are shifted from each other by 180 degrees. 5. The circuit for determining the traveling direction includes a circuit for detecting the received traveling direction signal information and generating a reproduced square wave.
A circuit for generating a first reproduction clock signal synchronized with the reproduction square wave, and π with the same cycle as the first reproduction clock signal.
The second recovered clock and the second recovered clock that are out of phase by
A clock generation circuit for forming a third reproduction clock having a phase opposite to that of the reproduction clock, and a reproduction square wave indicating the traveling direction,
A first shift register that takes in bit data by the second reproduction clock, a second shift register that takes in a reproduction square wave indicating the traveling direction as bit data by the third reproduction clock, in predetermined byte units, A first logical operation circuit for performing a logical operation of each bit data fetched in the first shift register and each bit data fetched in the second shift register and inverted, and fetched in the first shift register 2. The traveling direction of the moving body according to claim 1, further comprising a second logical operation circuit that performs a logical operation on each bit data that has been inverted and each bit data that has been taken into the second shift register. Judgment system. 6. The traveling direction of the moving body is determined from a combination of an output of the first logical operation circuit and an output of the second logical operation circuit. A moving direction determination system for a moving body. 7. A step of incrementing the count value of either the forward direction integrating means or the backward direction integrating means according to the running direction determination result obtained for each of a plurality of bytes forming one data. The traveling direction determination system for a mobile body according to claim 6. 8. The majority decision judging means, when the traveling direction judging operation is completed for all of a plurality of bytes forming one data, the majority decision judging means calculates the count value of the forward direction integrating means and the reverse direction integrating. 8. The traveling of the moving body according to claim 7, wherein information for judging the traveling direction having the larger count value as the current traveling direction of the moving body is output by comparing with the count value of the means. Direction determination system. 9. The conclusion of the majority decision means is judged to be valid only when the result of judgment by the data quality judgment means that the received data is normal is output. The traveling direction determination system for a mobile body according to claim 8. 10. A wireless transmitter installed on a road, which simultaneously transmits data on road information and traveling direction signal information for determining a traveling direction of a moving body in synchronization with the data, and a wireless transmitter installed on the side of the moving body. A traveling direction determination system for a moving body, comprising a traveling direction determination circuit which is provided, and which receives and arithmetically processes the traveling direction determination signal information, and the traveling direction received from the wireless transmitter. A first step of determining the traveling direction of the moving body in units of bytes forming the data from the direction determination signal information, and repeatedly executing the above determination operation for each of a plurality of bytes forming the one data. A second step, wherein the plurality of traveling direction determination results obtained for each of a plurality of bytes forming the one data are individually accumulated for each of the forward direction and the backward direction, and the forward direction integrating means and the backward direction integrating means A third step of storing, after the above operation is completed for all of the plurality of bytes forming the one data, the integrated counts stored in the forward integration means and the backward integration means respectively A fourth step of comparing the values by majority decision and selecting the one having the larger count value; a fifth step of judging whether or not the received data is normal data by the data quality judging means, A sixth step of judging that the judgment result of the majority decision judging means is valid only when the data quality judging means judges that the received data is normal, and a seventh step of displaying the judgment result of the majority judgment judging means. The moving direction system of the moving body, which is characterized by comprising the steps of and.