JPH0471240B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a traffic information transmitting device for listening to traffic information while a vehicle is traveling on a motorway such as an expressway or other roads.

In such a traffic information transmitting device, the carrier wave frequency at which the traffic information is transmitted is known in advance before the traffic information passes through the area where the traffic information is transmitted by radio waves, and therefore the tuning operation is performed. must be carried out. Otherwise,
It is not possible to listen to traffic information while driving on the road.

An object of the present invention is to provide a traffic information transmitting device that can reliably listen to traffic information in a predetermined traffic information receiving area while driving on a road.

The present invention provides first transmitting means 9, 10, 11, 1
2 and second transmitting means 15, 14, 18, 19, the first transmitting means 9, 10, 11, 12 are configured to transmit information to predetermined transmitters on the roads 1, 2 side. Provided in sections 6 and 7 of 1,
The second transmitting means 15, 14, 18, 19 modulates carrier frequencies c1 and c2, which are not broadcast within the frequency band of radio broadcasting, with traffic information and transmits them at a predetermined output. It is provided in a predetermined second section on the upstream side of sections 6 and 7, and the second section, including roads 1 and 2, is covered with a shield member 41 that shields from radio waves of radio broadcasting. Information transmission frequency c
This is a traffic information transmitting device that modulates the same carrier frequency as the radio broadcasting frequency with guidance voice information representing 1 and c2 and transmits it at a predetermined output.

In a preferred embodiment, the second transmitting means 15,
14, 18, and 19 are provided in a predetermined second section that is not covered with the shield member 41, and are confirmation signals having the same carrier frequency c1, c as that of the first transmitting means.
2 and transmits with a predetermined output.

In a preferred embodiment, the second transmitting means 1
5, 14, 18, 19 are provided in a predetermined second section not covered by the shield member 41, and are tuned frequency control signals to the first transmitting means 9, 10, 1.
Carrier frequency c of traffic information transmitted from 1 and 12
It is characterized by modulating carrier frequencies c2 and c1 different from those of 1 and c2, and transmitting with a predetermined output.

Furthermore, a preferred embodiment is characterized in that the second transmitting means 15, 14, 18, 19 are provided in a second predetermined section provided near a toll gate.

FIG. 1 is a plan view of one embodiment of the present invention. A motorway such as an expressway has an up line 1 and a down line 2 provided in parallel. This up line 1
Preparation areas 4 and 5, such as toll gates, are provided corresponding to the up line 1 and the down line 2, where automobiles 3 pay tolls when entering the up line 1 and the down line 2, respectively. Traffic information receiving areas 6 and 7, which are first sections, are provided in the up lane 1 and the down lane 2, respectively. In the traffic information receiving area 6, a car 3 traveling in the up lane 1 in the direction of arrow 8 is detected.
Traffic information such as traffic jam situations that are useful in traffic is transmitted from a transmitting device 9 in the form of radio waves through an antenna 10 implemented by a leaky cable or the like. Similarly, traffic information useful for vehicles traveling on the down line 2 is transmitted to the down line 2 from a transmitting device 11 in the traffic information receiving area 7 via an antenna 12 using radio waves. This traffic information receiving area 6, 7
The carrier wave frequency being transmitted is different from the carrier wave frequency used for general radio broadcasting. Selected as the carrier frequency value. These carrier frequencies in the traffic information receiving areas 6 and 7 are set to different values to prevent mutual interference.
These are defined in c1 and c2, respectively.

FIG. 2 is a perspective view of the preparation area 4, which is the second section. This preparation area 4 is covered by a shield member 41 made of a grounded conductive material, such as iron. This preparation area 4 is the upstream line 1
This is the area through which the automobile 3 entering the area passes, and is located upstream of the traffic information receiving area 6. In this preparation area 4, the electric field strength of the radio broadcast is weak or zero due to the action of the shield member 5. A loop antenna 14 is embedded in the road 1a of the preparation area 4. A transmission signal is sent to the loop antenna 14 from the transmission circuit 15 at the same carrier frequency as the existing radio broadcasting frequency and with a weak transmission output so that the reception area is a narrow range within the shield member 41. . The transmission signal is created by modulating a carrier wave with the same carrier frequency as the frequency of the radio broadcast by a guidance audio signal that announces the carrier frequency c1 of traffic information being transmitted in the traffic information receiving area 6. has been done. For example, when c1 is 1600Hz, "traffic information can be heard at a frequency of 1600kHz."
It may be the voice that says. When there are multiple radio broadcasting stations, the transmitting device 15 modulates each carrier wave frequency, which is the same as each frequency of the radio broadcasting, with an audio signal and transmits the modulated signals. Therefore, when the vehicle 3 reaches the preparation area 4 with a certain radio broadcast still being received by the receiving device 16 such as a conventional car radio installed in the vehicle 3,
The radio broadcast cannot be heard. Instead of this radio broadcast, the audio can be listened to. Therefore, the driver of the automobile 3 changes the tuning frequency of the receiving device 16 so that it can receive the carrier wave frequency c1 instructed by the voice, and drives on the up line 1 in the direction of the arrow 8. As a result, the carrier wave frequency c1 can be received in the traffic information receiving area 6, so that traffic information can be heard.

According to another aspect of the invention, in the preparation area 4 a carrier frequency signal having a frequency c1 modulated by an audio frequency signal may be emitted from the antenna 14 by means of a transmitting device 15. As a result, when the tuning frequency of the receiving device 16 is tuned to the carrier frequency c1 in the preparation area 4, an audible frequency signal that functions as a confirmation signal can be heard. Therefore, the receiving device 16 is connected to the carrier wave frequency c.
1, and the traffic information can be reliably heard in the traffic information receiving area 6. This audio frequency signal may be, for example, a "beep" sound.

Similarly, in relation to the downlink 2, the preparation area 5 is also configured in such a way that the radio field strength of the radio broadcast is weak or zero, and is transmitted by the transmitting device 18 from the traffic information receiving area 7 of the downlink 2. Traffic information is transmitted from an antenna 19 embedded in the road 1b on the upstream side using the same carrier frequency as the radio broadcast frequency. The carrier wave frequency in this preparation area 5 is modulated by an audio signal that is sent out in the traffic information receiving area 7 and notifying the carrier wave frequency c2. Instead of this audio signal, for example,
It may be an audio frequency signal.

Still another embodiment of the present invention will be described with reference to FIG. In the predetermined traffic information receiving areas 6, 7 of the up line 1 and down line 2, traffic information is transmitted to the transmitting devices 9, 11 and 7 using carrier frequencies c1, c2 that are different for each up line 1 and down line 2. It is transmitted by antennas 10 and 12. In the preparation area 4 located upstream of the traffic information receiving area 6 of the up line 1, the carrier wave frequency transmitted in the traffic information receiving area 6 corresponding to the up line 1
The same carrier frequency as c1 is modulated with an audio frequency signal and transmitted by the transmitter 15 and antenna 14. Similarly, in the preparation area 5 on the upstream side of the traffic information receiving area 7 of the down line 2,
The same carrier frequency c2 as the carrier frequency c2 being transmitted in the traffic information receiving area 7 corresponding to the down line 2 is modulated with an audio frequency signal and transmitted by the transmitting device 18 and antenna 19.
The audio frequency signal may be a monotonous sound, such as a "beep", or it may be a sound containing meaningful information.

The driver of the automobile 3, which has proceeded along the road 1a to the upline 1, changes the tuning frequency of the receiving device 16 in the preparation area 4 and receives the carrier wave frequency c1. This allows you to hear audio frequencies. After completing this tuning operation, if you are traveling on the up line 1, you can listen to traffic information when you enter the traffic information receiving area 6. A similar operation is performed regarding the down line 2. Carrier frequency c1, c2
is selected at a different frequency from that of the radio broadcast, and therefore the preparation areas 4, 5 do not have to be constructed in a shielded manner so that the electric field strength of the radio broadcast is weak or zero.

Still another embodiment of the present invention will be described with reference to FIG. In the predetermined traffic information receiving areas 6 and 7 of the up line 1 and the down line 2, traffic information is transmitted to the up line 1 and the down line 2 using different carrier frequencies c.
It is transmitted by radio waves using 1 and c2. In the preparation area 4 upstream of the traffic information receiving area 6 of the up line 1, the carrier wave frequency c1 transmitted in the traffic information receiving area 6 corresponding to the up line 1
Transmitting device 1 transmits a residual carrier frequency c2 different from
5 and antenna 14. The carrier frequency c2 in this preparation area 4 is modulated by a signal having a frequency H, which may be an audio frequency. Regarding the down line 2, in the preparation area 5 upstream of the traffic information receiving area 7, there is a traffic information receiving area 7 corresponding to the down line 2.
The remaining carrier wave frequency c1, which is different from the carrier wave frequency c2 that is being sent out in FIG. The automobile 3 traveling on these up lines 1 and down lines 2 is equipped with a receiving device 20 for receiving traffic information. The automobile 3 may be equipped with a receiving device 16, such as a car radio, for receiving conventional radio broadcasts.

FIG. 3 shows a specific configuration of the receiving device 20. As shown in FIG. In this receiving device 20, a signal received from an antenna 21 is given to a tuner 22. The tuner 22 is supplied with signals from voltage sources 23 and 24 via a changeover switch 25 and a line 26 .
The common contact 27 of the changeover switch 25 is the individual contact 2
8 and the voltage from the voltage source 23 is connected to the tuner 2.
2, the tuner 22 is tuned so that it can receive carrier frequency c1. Further, when the common contact 27 of the changeover switch 25 is electrically connected to another individual contact 29 and the voltage from the voltage source 24 is applied to the tuner 22,
The tuning frequency of this tuner 22 is the carrier frequency
It becomes c2. Such tuners include, for example, variable voltage dependent variable capacitance diodes and are well known to those skilled in the art as so-called electronically tuned tuners. The output received and demodulated by the tuner 22 is applied from a line 30 to a speaker 32 via an amplifier circuit 31 and converted into sound. Further, the demodulated output from line 30 is given to bandpass filter 33. The band pass filter 33 is
Wave only a signal with frequency H that functions as a tuning frequency control signal. This signal is applied to a detection circuit 34 that performs envelope detection or rectification. When the detection circuit 34 receives a signal having a frequency H via the bandpass filter 33,
A high level signal is applied to line 35, thereby inverting the stable state of flip-flop 36. Flip-flop 36 is a so-called toggle flip-flop, which responds to a rising waveform from a low level to a high level via line 35 and changes the level on line 37 to high or low each time the rising waveform is received. Change and hold alternately. The changeover switch 25 conducts the common contact 27 to the individual contact 28 when the line 37 is at a high level, and conducts the common contact 27 to the individual contact 29 when the line 37 is at a low level.

The tuning frequency of the tuner 22 of the receiving device 20 is c
Assume that it is 1. At this time, the output of flip-flop 36 is at high level, and contact 2
7 and 28 are conductive. Such a receiving device 2
0 arrives at the preparation area 4.
In this preparation area 4, radio waves of frequency c2 continue to be emitted. Therefore, no signal is derived from tuner 22 on line 30. When the vehicle reaches the traffic information receiving area while traveling on the up line 1 in this state, the carrier wave frequency c1 is received, and the traffic information is audible from the speaker 32 via the amplifier circuit 31 and can be heard.

Assume that the tuning frequency of the tuner 22 is c2. At this time, the flip-flop 36 outputs a low level signal to the line 37, and the common contact 27 of the changeover switch 25 is electrically connected to the individual contact 29.

When the motor vehicle 3 enters the preparation area 4, a signal having a frequency H is derived from the tuner 22 on the line 30. As a result, the output from the detection circuit 34 changes from low level to high level on line 35. Therefore, flip-flop 3
6 changes the steady state and derives a high level signal on line 35. Therefore, the common contact 27 of the changeover switch 25 is electrically connected to the individual contact 28. In this way, the voltage from the voltage source 23 is applied to the tuner 22, and the reception frequency of the tuner 22 becomes the carrier frequency c1. Therefore, when the vehicle is subsequently traveling in the traffic information receiving area 6 of the up line 1, traffic information can be heard through the speaker 32. Such an operation is similar in relation to the down line 2 as well. The preparation areas 4 and 5 do not need to be constructed so that the electric field strength of the radio broadcast is weak or zero, and the carrier frequencies c1 and c2 are selected to be different values from the frequency of the radio broadcast.

The invention can be widely implemented not only in relation to upline 1 and downline 2, but also in connection with other roads.

As described above, according to the present invention, when a vehicle enters a traffic information receiving area while driving on a road, traffic information can be reliably received.

[Brief explanation of the drawing]

FIG. 1 is a simplified plan view for explaining one embodiment of the present invention, FIG. 2 is a perspective view of the preparation area 4,
FIG. 3 is a block diagram showing a specific configuration of the receiving device 20. As shown in FIG. 1...Up line, 2...Down line, 3...Car, 4,5
...Preparation area, 6, 7...Traffic information reception area, 9, 1
1, 15, 18... transmitting device, 10, 12, 14,
19, 21... antenna, 16, 20... receiving device,
41... Shield member, c1, c2... Carrier frequency.

Claims (1)

[Scope of Claims] 1. A traffic information transmitting device comprising first transmitting means 9, 10, 11, 12 and second transmitting means 15, 14, 18, 19, the first transmitting means 9, 10, 11, 12 are provided in predetermined first sections 6, 7 on the roads 1, 2 side,
The second transmitting means 15, 14, 18, 19 modulates carrier frequencies c1 and c2, which are not broadcast within the frequency band of radio broadcasting, with traffic information and transmits them at a predetermined output. It is provided in a predetermined second section upstream of sections 6 and 7, and the second section, including passages 1 and 2, is covered with a shield member 41 that shields from radio waves of radio broadcasting. Information transmission frequency c
A traffic information transmitting device that modulates the same carrier frequency as the radio broadcasting frequency with guidance voice information representing 1 and c2 and transmits it at a predetermined output. 2 The second transmitting means 15, 14, 18, 19 are
It is provided in a predetermined second section not covered by the shield member 41, modulates the same carrier frequencies c1 and c2 as the first transmitting means with the confirmation signal, and transmits with a predetermined output. The traffic information transmitting device described in Section 1. 3 The second transmitting means 15, 14, 18, 19 are
What are the traffic information carrier frequencies c1 and c2 provided in a predetermined second section not covered by the shield member 41 and transmitted from the first transmitting means 9, 10, 11, and 12 using tuned frequency control signals? The traffic information transmitting device according to claim 1, which modulates different carrier frequencies c2 and c1 and transmits with a predetermined output. 4 The second transmitting means 15, 14, 18, 19 are
The traffic information transmitting device according to any one of claims 1 to 3, which is provided in a second predetermined section provided near a toll gate.