JPH10213662A - Optical vehicle sensing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To perform bi-directional communication with a on-vehicle communication device and detection of a vehicle with a single light-emitting part, drive part, photo- detecting part, and amplification part by providing a signal addition part, etc., wherein sensing light-projection pulse signal and communication pulse modulation signal are added together. SOLUTION: Communication modulation pulse signal 101 generated at a communication modulation pulse signal generating part 5 and sensing light-projecting pulse 117 generated at a sensing light-projecting pulse generating part 20 are added together at a signal addition part 21, and a common light-emitting part 23 projects common irradiation light 120. The common irradiation light 120 is photo-detected not only with an on-vehicle communication device 3 but with a common photo-detecting part 24 as reflection light 121 from a road surface 1 and a vehicle 2. An irradiation light 104 of transmission data from the on-vehicle communication device 3 is also photo- detected with the common photo-detecting part 24. An amplification signal 123 of a reception signal 122 which is the output of the common photo-detecting part 24 is distributed into two channels with a signal distribution part 26a. One of them is used for vehicle detection while passing the first BPF 27, while the other is signal- processed with a signal processing part 11 while passing the second BPF 28.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical vehicle sensing device which is installed on a road and has a function of two-way communication with a vehicle equipped with a vehicle-mounted communication device and a function of detecting a vehicle traveling on the road. .

[0002]

2. Description of the Related Art FIG. 20 is a block diagram showing a configuration of a conventional optical vehicle sensing device, FIG. 21 is an installation diagram of the optical vehicle sensing device, and FIG. 22 is infrared rays emitted and received by the optical vehicle sensing device. FIGS. 23 and 24 show the frequency distribution of light rays.
FIG. 4 is a waveform diagram of infrared rays emitted and received by the optical vehicle sensing device. In the figure, 1 is a road, 2 is a vehicle traveling on the road 1 in the direction of the arrow, A is a light emitter / receiver that is installed on the road 1 and emits and receives infrared rays, B is a communication that is installed beside the road, and A controller that performs vehicle detection processing, M is an optical vehicle sensor composed of a light emitting and receiving device A and a controller B, 3 is a two-way communication using an optical vehicle sensor M mounted on a vehicle and an infrared ray. The transmission data 1 such as traffic jam information for a vehicle traveling on the road 1 in the direction of the arrow
The transmission data generator 5 for generating the communication pulse modulation signal 101 from the transmission data from the transmission data generator 4
The communication pulse modulation signal generator 6 generates the communication light emitting unit drive current 1 based on the output of the communication pulse modulation signal generator 5.
A communication drive unit for turning on and off 02, a communication light-emitting unit for emitting light in accordance with the current of the communication drive unit, 10
Reference numeral 3 denotes irradiation light emitted from the communication light emitting unit 7, reference numeral 104 denotes irradiation light irradiated according to frequency-modulated transmission data from the vehicle-mounted communication device 3, and reference numeral 8 denotes communication which receives the irradiation light 104 and converts it into a voltage. The communication light-receiving unit 9 removes a DC component due to disturbance light from the frequency modulation signal 105, which is the output signal of the communication light-receiving unit 8, and amplifies the signal so that the signal can be easily processed. A frequency demodulation unit that generates a frequency demodulation signal 107 from the amplified frequency modulation signal 106 from the unit 9, 11 is a signal processing unit that processes the frequency demodulation signal 107 from the frequency demodulation unit 10, and 12 is an arrow on the road 1. A sensing light emitting pulse generating unit 13 for generating a sensing light emitting pulse signal 108 for irradiating to detect a vehicle traveling in the direction, and a sensing light emitting pulse 13 is output from the sensing light emitting pulse generating unit 12. On the drive current 109, sensing drive unit for off, 14 sensing the light emitting unit that emits light in response to the sensed drive current 109 sensing the drive unit 13, 110
Is irradiation light for vehicle detection emitted from the light emitting unit for sensing 14,
111 is the irradiation light 11 for vehicle detection from the light emitting unit 14 for sensing
0 is the reflected light from vehicle 2 and road 1, 15 is the reflected light 11
A light receiving unit 16 receives light 1 and converts it into a voltage. A sensing amplifying unit 16 removes a DC component due to disturbance light from a reflected signal 112 which is an output signal of the sensing light receiving unit 15 and amplifies a signal so as to facilitate signal processing. , 17 is a signal comparing unit that compares the reflected signal 113 amplified by the sensing amplifier 16 with a reference voltage, 18 is a vehicle detecting unit that outputs a vehicle detecting signal 115 from a comparison result 114 of the signal comparing unit 17, and 19 is a vehicle. A traffic information calculation unit for constantly grasping the traffic congestion state using the detection signal 115 and transmitting road congestion information 116 such as traffic congestion information to the transmission data generation unit 4. 40 is an optical vehicle sensor M and in-vehicle communication. A two-way communication area for communication with the device 3, a vehicle detection area 41 for detecting a vehicle, A is a light emitting and receiving device installed on a road, B is a controller installed on a roadside, and a is a communication device. Departure Frequency spectrum of the communication pulse modulated signal 101 emitted by section 7, b is sensed light emitting section 1
4, the frequency spectrum of the sensing light emitting pulse signal 110 radiated at 4, the c is the frequency spectrum of the frequency-modulated irradiating light 104 of the vehicle-mounted communication device 3 received by the communication light receiving unit 8, and the d is the sensing light emitting unit 14. And e is the waveform of the communication pulse modulation signal 101 emitted by the communication light-emitting unit 7.

Next, the operation will be described. The optical vehicle sensing device is roughly divided into an in-vehicle communication device 3 mounted on a vehicle.
And a vehicle detection operation.

First, the communication operation will be described. FIG.
In the communication pulse modulation signal generation unit 5, the transmission data 100 such as traffic congestion information and construction information to the in-vehicle communication device 3 mounted on the vehicle 2 traveling on the road 1 generated by the transmission data generation unit 4 is transmitted. , Communication pulse modulated signal 101
Pulse modulation. The communication light emitting unit 7 enters a light emitting and non-light emitting state by the communication driving unit 6 that turns on and off the communication light emitting unit drive current 102 in synchronization with the communication pulse modulation signal 101. The illuminating light 103 from the communication light emitting unit 7 is received by the on-vehicle communication device 3, and the driver of the vehicle 2 displays the traffic congestion status and the required time using display or voice guidance, and is set by the driver using a keyboard or a touch panel. The transmission data such as the destination information is transmitted to the optical vehicle detector M by the irradiation light 9. The irradiation light 104, which is transmission data from the in-vehicle communication device 3, is received by the communication light receiving unit 8 and converted into a voltage, and the communication amplifying unit 9 removes a steady unnecessary DC component due to disturbance light. Amplify. The amplified frequency modulated signal 106 is supplied to the frequency demodulation unit 10
After the frequency demodulation at, the signal processing unit 11 performs signal processing.

Next, the vehicle detection operation will be described. FIG.
0, the sensing light emitting pulse signal 108 used for detecting the vehicle 2 generated by the sensing light emitting pulse generator 12
And the sensing light emitting unit drive current 10 controlled by the sensing drive unit 13 that turns on and off the current in synchronization with it.
By 9, the light emitting unit for sensing 14 enters a light emitting and non-light emitting state. Road surface 1 of irradiation light 110 from the sensing light emitting unit 14
And the reflected light 111 from the vehicle 2 is received by the sensing light receiving unit 15, and the reflected signal 1 is an output signal of the sensing light receiving unit 15.
Numeral 12 denotes a sensing amplification unit 16 which removes a steady unnecessary DC component due to disturbance light and then voltage-amplifies. Normally, a signal obtained by amplifying the reflected light including the reflected light from the vehicle 2 is higher than a reflected signal obtained by amplifying only the reflected light from the road 1.
The amplified reflected signal 11 is compared with a reference voltage preset to a value higher than the signal level obtained by amplifying only the reflected light of the road 1.
When 3 is large, it is determined that the vehicle 2 exists, and the vehicle detection signal 115 is transmitted to the traffic information calculation unit 19. The traffic information calculation unit 19 constantly grasps the traffic congestion state using the vehicle detection signal 115, and transmits the traffic congestion information 116 such as the traffic congestion information obtained thereby to the transmission data generation unit 4.

[0006]

As described above, the conventional optical vehicle sensing apparatus uses a transmitting light pulse signal having a frequency component of 0 to 1.5 MHz depending on the sensing light emitting pulse signal and the content of the data to be transmitted. Overlap on the frequency axis and interfere with each other, so that a vehicle detection area that emits and receives infrared rays for vehicle detection, and light emission and reception for two-way communication with the onboard communication device It is necessary to spatially separate the two-way communication area for performing the above. for that reason,
Two systems of light emitting unit, drive unit, light receiving unit and amplifying unit are required for two-way communication with the on-board communication device mounted on the vehicle and for detecting the vehicle, and a mechanism for separating the light emitting and receiving area The structure was complicated.

[0007] The present invention has been made to solve the above-described problems, and has two-way communication with a vehicle-mounted communication device.
It is an object of the present invention to detect a vehicle by using one light emitting unit, drive unit, light receiving unit, and amplifying unit in the same light emitting and receiving area.

[0008]

An optical vehicle sensing device according to a first aspect of the present invention has a frequency higher than a frequency of a pulse modulation signal for communication and a frequency used for frequency modulation of transmission data of a vehicle-mounted communication device. Means for generating a first sensing light emitting pulse signal having a frequency different from that of the first
Means for voltage-adding the sensing light emitting pulse signal and the communication pulse modulation signal, means for dividing and outputting the output signal of the amplifier section into two, and the first sensing signal among the output signals of the above means Means for passing only a signal having the frequency component of the light emitting pulse signal for use, means for comparing the output signal of the above-mentioned means with a reference voltage, Means for passing only the frequency used for frequency modulation.

An optical vehicle sensing device according to a second aspect of the present invention comprises:
According to the first aspect of the present invention, a first reference frequency which is higher than the frequency of the pulse modulation signal for communication and which is different from the frequency used for frequency modulation of transmission data of the vehicle-mounted communication device is generated. Means for generating, a means for generating a second sensing light projection pulse signal having a lower frequency than the communication pulse modulation signal, and amplitude modulation of the output signal of the means using the output signal of the means described above. Means for voltage-adding the output signal of the above-mentioned means and the pulse modulation signal for communication, and means for outputting the output signal of the first signal distribution unit when the second sensing light emitting pulse signal is at a high level. Means for passing the signal as it is and not passing when the signal is at a low level, and means for passing only the frequency component of the first reference frequency which is the carrier used for the amplitude modulation of the second sensing light emission pulse signal among the output signals of the means. And before And means for outputting an amplitude proportional to the voltage of the output signal of the unit is obtained by and means for comparing the output and the reference voltage of the aforementioned means.

[0010] An optical vehicle sensing device according to a third aspect of the present invention comprises:
Means for controlling the transmission intervals of the sensing light emitting pulse and the third sensing light emitting pulse signal according to the second invention, and the third sensing light emission controlled by the output signal of the means Means for generating a pulse.

An optical vehicle sensing device according to a fourth aspect of the present invention is
Means for automatically controlling the amplitude of the reference frequency used to modulate the sensing projection pulse in the second invention; and generating a second reference frequency having an amplitude controlled by the output signal of the means. Means for performing the above.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION

Embodiment 1 FIG. FIG. 1 is a block diagram showing Embodiment 1 of the present invention.
19 to 19, A, B, and M are the same as those in FIG. 17 of the conventional apparatus, and 20 to 28 are apparatuses newly added to the conventional apparatus. Reference numeral 20 denotes a first sensing light emitting pulse generator for generating a first sensing light emitting pulse 117 used for vehicle sensing at a higher frequency than the communication pulse modulated signal 101 from the communication pulse modulated signal generator 5. , 21 are a signal adding unit for adding the communication pulse modulated signal 101 and the first sensing light emitting pulse 117 in terms of voltage, and 22 is a signal adding unit 21.
A common light-emitting unit that adjusts the common light-emitting unit drive current 119 in proportion to the addition signal 118a output from the common light-emitting unit;
0 is a common irradiation light including the communication pulse modulation signal 101 and the first sensing light emission pulse signal 117 emitted from the common light emitting unit 23, and 121 is a reflection light of the common irradiation light 120 from the road surface 1 and the vehicle 2 , 24 are a common light receiving unit for converting the reflected light 121 and the irradiation light 104 from the on-vehicle communication device into a voltage.
Reference numeral 5 denotes a common amplifying unit that removes a DC component due to disturbance light from the received signal 122 from the common light receiving unit 24 and amplifies the received signal so that the signal can be easily processed. Reference numeral 26a denotes an amplified received signal 123 from the common amplifying unit 25. And a signal distribution unit 27 that distributes only the frequency of the first sensing light emission pulse signal 117 of the amplified reception signal 123 that is the output signal of the signal distribution unit 26a. The electric band-pass filter 28 is a second electric band-pass filter that passes only the frequency used for frequency modulation of the transmission data of the on-vehicle communication device 3 in the amplified reception signal 123 that is the output signal of the signal distribution unit 26a. Filter.

Next, the operation will be described. In FIG. 1, the communication pulse modulation signal 101 generated by the communication pulse modulation signal generation unit 5 and the first sensing light emission pulse 117 generated by the first sensing light emission pulse generation unit 20.
Are electrically added in the signal adding unit 21 and the common light emitting unit 2 is driven by the common light emitting unit driving current 119 adjusted by the drive unit 22 in proportion to the output signal of the signal adding unit 21.
3 projects the common irradiation light 120. The common irradiation light 120 is received by the on-vehicle communication device 3 and received by the light receiving unit 24 as reflected light 121 from the road surface 1 and the vehicle 2. The common light receiving unit 24 also receives the irradiation light 104 of the frequency-modulated transmission data from the in-vehicle communication device 3. The reception signal 122, which is the output signal of the common light receiving unit 24, is subjected to voltage amplification while removing the unsteady DC component due to disturbance light in the common amplification unit 25. The amplified received signal 123 is distributed to two routes by the signal distributor 26 a, and one of the first electrical signals passes only the frequency of the first sensing light emitting pulse signal 117 generated for vehicle detection. Unnecessary signals are removed by passing the signal through a passive bandpass filter 27, and then the signal comparison unit 17 compares the output signal of the first electrical bandpass filter 27 with a preset reference voltage to detect a vehicle. Do. Another one of the received signals 123 distributed by the signal distributor 26a is passed through a second electric band-pass filter 28 that passes only the frequency used for frequency modulation of the transmission data of the on-vehicle communication device 3. Unnecessary signals are removed, and then the frequency demodulation unit 10 frequency-demodulates the output signal of the second electrical bandpass filter 28 to generate a frequency demodulation signal 107, and the signal processing unit 11 converts the frequency demodulation signal 107 into a signal. To process.

Next, the frequency characteristics of the infrared ray irradiated and received by the light emitting and receiving device A will be described with reference to FIGS. In FIG. 5, a is the frequency spectrum of the communication pulse modulation signal 101 emitted by the common light emitting unit 7, and f is the frequency spectrum of the first sensing light emission pulse signal 117.
In FIG. 6, c is the frequency spectrum of the frequency-modulated irradiation light 104 of the on-vehicle communication device 3 received by the common light receiving unit 8, and g is the frequency spectrum of the common reflection light 121 of the common irradiation light 120 from the road 1 and the vehicle 2. It is.

Next, an addition signal 11 emitted from the light emitting and receiving device A
8 is described with reference to FIGS. 7, 8, and 9. FIG. In FIG. 7, the first sensing light emitting pulse generator 20 is shown.
, The waveform of the first sensing light emitting pulse signal 117 generated in step (a), i in FIG. 8, the waveform of the communication pulse modulation signal 101 generated in the communication pulse modulation signal generation unit 5, and j in FIG. H of the light emitting pulse signal 117 for sensing
And a waveform i of the pulse modulation signal 101 for communication is a waveform of an addition signal 118 obtained by electrically adding the waveform i.

As described above, the communication pulse modulated signal 101
Frequency spectrum a of the first sensing light emitting pulse signal 117 and the frequency spectrum f of the first sensing light emitting pulse signal 117 are signals separated on the frequency axis. The influence of the first sensing light emitting pulse signal 117 on the communication pulse modulated signal 101 is eliminated. Similarly, in the signal received by the common light receiving unit 24,
A frequency spectrum c used for frequency modulation of transmission data of the in-vehicle communication device;
Are separated on the frequency axis, so that the first electrical bandpass filter 27,
By passing through the second electric band-pass filter 28, mutual interference can be prevented.

Embodiment 2 FIG. FIG. 2 is a block diagram showing a second embodiment of the present invention.
0,11,17-19,21-26,28, A, B, M
Is the same as that of FIG. 1 of the first embodiment of the invention, and reference numerals 26b and 29 to 33 denote devices newly added to the optical vehicle sensor of the first embodiment. 29
Is a second sensing light emission pulse signal 124 having a lower frequency than that of the communication pulse modulation signal 101 used for detecting a vehicle.
, A receiving signal distributor for dividing and outputting the second sensing light emitting pulse signal 124 into two, and 30 a second sensing light emitting pulse signal. The first reference frequency 1 is used for amplitude modulation of the first reference frequency 1 and is higher in frequency than the pulse modulation signal 101 for communication.
The first reference frequency generator 31 for generating the first reference frequency 125 outputs the first reference frequency 125 as it is when the second sensing light emitting pulse signal 124, which is the output signal of the reception signal distributor 26b, is at a high level, A sensing light emitting pulse modulation signal generator that outputs nothing when the signal is at a low level, 118b electrically connects the amplitude modulation signal 126 and the communication pulse modulation signal 101 which are output signals of the sensing light emitting pulse modulation signal generator 31. An addition signal, which is an output signal of the signal addition unit 21, which is added to the received signal distribution unit 26 b
When the sensing light emitting pulse signal 124 is at a high level, the output signal of the signal distribution unit 26a is passed as it is, and when it is at a low level, the output signal of the signal distribution unit 26a is not passed. A third electric band-pass filter that passes only the frequency of the first reference frequency 125 among the output signals of the third electric band-pass filter 34 outputs a reflected voltage 127 proportional to the amplitude of the output signal of the third electric band-pass filter 33. This is a level detector that performs

Next, the operation will be described. In FIG. 2, the second sensing light emitting pulse signal 124 generated by the second sensing light emitting pulse generating unit 29 uses the first reference frequency 125 from the first reference frequency generating unit 30. Amplitude modulated. The output signal of the sensing light emitting pulse modulation signal generating section 31 becomes the first reference frequency 125 when the second sensing light emitting pulse signal 124 is at a high level, and is not output when the second sensing light emitting pulse signal 124 is at a low level.

The above-mentioned sensing light emitting pulse modulation signal generating section 3
The amplitude modulation signal 126 and the communication pulse modulation signal 101, which are the output signals of No. 1 and the communication pulse modulation signal 101, are voltage-added in the signal addition unit 21 and output as an addition signal 118b.
The common light emitting unit 23 emits the common irradiation light 1 by the current adjusted by the common drive unit 22 that adjusts the current in proportion to the common irradiation light 1.
20 is emitted.

The common irradiation light 120 is received by the on-vehicle communication device 3 and the reflected light 12 from the road surface 1 and the vehicle 2
The light is received by the light receiving unit 24 as 1. Further, the irradiation light 104 of the frequency-modulated transmission data from the in-vehicle communication device 3 is used.
Is also received by the light receiving section 24. The received signal 122 received by the light receiving unit 24 is subjected to voltage amplification while removing a stationary unnecessary DC component due to disturbance light in the common amplification unit 25.

The output signal of the common amplifying unit 25 is
At 6a, the signal is distributed to the reception signal control unit 32 and the second electric bandpass filter. The output signal of the signal distribution unit 26a is passed through the output of the signal distribution unit 26a as it is when the second sensing light emission pulse signal 124 is at a high level.
When the signal is at the low level, the signal passes through the reception signal control unit 32 that does not pass any signal, so that only the reception signal 123 when the second sensing light emission pulse signal 124 is emitted from the common light emitting unit 23 is used for vehicle detection. be able to. The output signal of the reception signal control unit 32 is a third electric bandpass filter 3 that passes only the frequency of the first reference frequency 125.
3 to remove unnecessary signals. The output signal of the third electrical bandpass filter 33 is converted by a level detector 34 into a reflected voltage 127 which is a voltage proportional to the amplitude. Then, the signal comparing section 17 compares the reflected voltage 127 with a preset reference voltage to detect a vehicle.

Next, the frequency characteristics of the infrared ray irradiated and received by the light emitter / receiver A will be described with reference to FIGS. In FIG. 10, a is the frequency spectrum of the communication pulse modulation signal 101 emitted by the common light emitting unit 7, and k is the frequency spectrum of the second sensing light emitting pulse information 124 generated by the sensing light emitting pulse generator 29. , L is the frequency spectrum of the amplitude modulated signal 126. In FIG. 11, c is the frequency spectrum of the frequency-modulated irradiation light 104 of the in-vehicle communication device 3 received by the common light receiving unit 8, m
Is a frequency spectrum of the common reflected light 121 of the common irradiation light 120 from the road 1 and the vehicle 2.

Next, a process of generating the amplitude modulation signal 126 irradiated by the light emitter / receiver A will be described with reference to FIGS. 12, 13, 14, 15, and 16. FIG. In FIG. 12, n is the waveform of the second sensing light emitting pulse signal 124 generated by the second sensing light emitting pulse generator 29, and o is generated by the first reference frequency generator 30 in FIG. In FIG. 14, p is a waveform of the first reference frequency 125, and p is an amplitude modulation signal 126 generated by the sensing light projection pulse modulation signal generation unit 31.
In FIG. 15, q is the waveform of the communication pulse modulation signal 101 generated by the communication pulse modulation signal generation unit 5,
In FIG. 17, r is the amplitude modulated signal 1 in the signal adder 21.
26 is a waveform of an addition signal 118b obtained by electrically adding the waveform n of 26 and the waveform o of the pulse modulation signal 101 for communication.

As described above, the second sensing light emitting pulse signal 124 is amplitude-modulated using the first reference frequency 125 to be an amplitude-modulated signal 126, so that the frequency spectrum a of the communication pulse-modulated signal 101 and The frequency spectrum f of the second sensing light emitting pulse 124 is a signal completely separated on the frequency axis. Even if the common irradiation light 120 is projected in the same direction using the same common light emitting part 23, the signal for communication Second sensing light emitting pulse 124 to pulse modulated signal 101
Is no longer affected. Similarly, in the signal received by the common light receiving unit 24, the frequency spectrum c used for frequency modulation of the transmission data of the on-vehicle communication device 3 and the frequency spectrum f of the second sensing light emission pulse signal 124 correspond to the frequency axis. Since they are completely separated from each other, they can be prevented from interfering with each other by passing through the second electric band-pass filter and the third electric band-pass filter, respectively. Further, by performing amplitude modulation and amplitude demodulation of the low-frequency sensing light emitting pulse signal, the signal comparison unit 17 can perform processing at a low operation frequency.

Embodiment 3 FIG. 3 is a block diagram showing a third embodiment of the present invention.
0,11,17-19,21-26,28,30-3
Reference numerals 4, A, B and M are the same as those in FIG. 2 of the second embodiment of the present invention, and reference numerals 35 and 36 are devices newly added to the second embodiment of the present invention.

Reference numeral 35 denotes a pulse interval control unit for transmitting a pulse interval control signal 128 for controlling a transmission interval of a light emission pulse signal used for vehicle detection, and 36 denotes a pulse interval control signal 128
Is a third sensing light emitting pulse generation unit that outputs a third sensing light emitting pulse signal 129 whose transmission interval is controlled by.

In FIG. 17, s denotes a third sensing light emitting pulse signal 12 having a wide pulse interval, which is controlled by the pulse interval control signal 128 so as to increase the pulse interval.
9. In FIG. 15, t is a third sensing light emitting pulse signal 129 having a narrow pulse interval, which is controlled by the pulse interval control signal 128 so as to narrow the pulse interval.

Next, the operation will be described with reference to FIGS. In the figure, a third sensing light emitting pulse signal 129 whose pulse sending interval is controlled by a pulse interval control signal 128 which is an output signal of the pulse interval controlling unit 35 is output from the third sensing light emitting pulse generating unit 36. Is done. The third sensing light emitting pulse signal 129 is supplied to the signal distribution unit 26.
The signal b is output to the sensing light emitting pulse modulation signal generation unit 31 and the reception signal control unit 32. The sensing light emitting pulse modulation signal generating unit 31 generates the third sensing light emitting pulse signal 12.
9 is amplitude-modulated using the first reference frequency 125 from the first reference frequency generator 30. The output signal of the sensing light emitting pulse modulation signal generator 31 becomes the first reference frequency 125 when the third sensing light emitting pulse signal 129 is at the high level, and is not output when the third sensing light emitting pulse signal 129 is at the low level.

The above-mentioned sensing light emitting pulse modulation signal generating unit 3
The amplitude modulation signal 126 and the communication pulse modulation signal 101, which are the output signals of No. 1 and the communication pulse modulation signal 101, are voltage-added in the signal addition unit 21 and output as an addition signal 118b.
The common light emitting unit 23 emits the common irradiation light 1 by the current adjusted by the common drive unit 22 that adjusts the current in proportion to the common irradiation light 1.
20 is emitted.

The common irradiation light 120 is received by the on-vehicle communication device 3 and the reflected light 12 from the road surface 1 and the vehicle 2 is received.
The light is received by the light receiving unit 24 as 1. Further, the irradiation light 104 of the frequency-modulated transmission data from the in-vehicle communication device 3 is used.
Is also received by the light receiving section 24. The received signal 122 received by the light receiving unit 24 is subjected to voltage amplification while removing a stationary unnecessary DC component due to disturbance light in the common amplification unit 25.

The output signal of the common amplifying unit 25 is
At 6a, the signal is distributed to the reception signal control unit 32 and the second electric bandpass filter. The output signal of the signal distribution unit 26a is passed through the output of the signal distribution unit 26a as it is when the third sensing light emission pulse signal 129 is at a high level.
The reception signal control unit 32 that does not pass anything at the time of the low level
Through the third sensing light emitting pulse signal 1
Received signal 1 when 24 is emitted from common light emitting section 23
Only 23 can be used for vehicle detection. The output signal of the reception signal control unit 32 is passed through a third electric bandpass filter 33 that passes only the frequency of the first reference frequency 125 to remove unnecessary signals. The output signal of the third electrical band-pass filter 33 is supplied to a level detector 34, where the reflected voltage 1 is a voltage proportional to the amplitude of the signal.
27. Then, the signal comparing section 17 compares the reflected voltage 127 with a preset reference voltage to detect a vehicle.

At this time, when the amplitude modulation signal 118b is generated using the third sensing light emitting pulse signal s having a wide pulse interval, the third sensing light emitting pulse signal 128 emitted by the common light emitting section 23 is generated. Is reduced, the power consumption and the amount of heat generated in the common light emitting unit 23 are reduced, and the amplitude modulation signal 118 is generated using the third sensing light emitting pulse signal t having a narrow pulse interval.
When b is generated, the number of pieces of information used for vehicle detection determination increases, so that the vehicle detection accuracy improves.

Embodiment 4 FIG. FIG. 4 is a block diagram showing a fourth embodiment of the present invention.
0,11,17-19,21-26,28,29,31
To 34, A, B, and M are the same as those in FIG.
And 37 to 39 are devices newly added to the conventional device. 37 has a judgment voltage 1 somewhat higher than the reference voltage and a judgment voltage 2 somewhat higher than the judgment voltage 1, and the reflected signal 127 which is the output signal of the level detector 34 is between the reference voltage and the judgment voltage 1. A signal comparison / determination unit that outputs a high-level reflected voltage determination signal 130, and outputs a low-level reflected voltage determination signal 130 when the reflected signal 127 is greater than the determination voltage 2.
38 outputs an amplitude control signal 131 for increasing the amplitude of the reference frequency used for amplitude modulation of the light projection pulse for sensing when the reflected voltage determination signal 130 is at a high level, and outputs the amplitude control signal 131 when the reflected voltage determination signal 130 is at a low level. Is an amplitude control unit that outputs an amplitude control signal 131 for reducing the amplitude of a reference frequency used for amplitude modulation of the sensing projection pulse. 39 is a second amplitude control signal that is controlled by the amplitude control signal 131 from the amplitude control unit 38. This is a second reference frequency generation unit that outputs the reference frequency 132 to the light projecting pulse modulation unit 31 for sensing.

FIG. 19 is a diagram showing the relationship among the reflected voltage 127 and the reference voltage, the first determination voltage, and the second determination voltage. In FIG. 19, u is a reflected voltage 127 which is an output signal of the level detector 34, v is a reference voltage to be compared with the reflected voltage 127, w is a first determination voltage used as a determination value for performing amplitude control, and x is an amplitude. This is a second determination voltage used as a determination value for performing control.

Next, the operation will be described with reference to FIGS. In the figure, when the input reflected voltage 127 is between the reference voltage v and the first determination voltage w, the signal comparison / determination unit 37 adjusts the amplitude of the amplitude modulation signal 126 emitted from the common light emitting unit 23 to the optimum value. , And outputs a high-level reflected voltage determination signal 130 to the amplitude control unit 38. When the reflected voltage 127 is higher than the second determination voltage s, the common light emitting unit 23 emits light. It determines that the amplitude of the amplitude modulation signal 126 is larger than the optimum value, and outputs a low-level reflected voltage determination signal 130 to the amplitude controller 38. When the reflected voltage 127 is between the first determination voltage w and the second determination voltage x, it is determined that the amplitude of the amplitude control signal 132 emitted from the light emitting unit 23 is the optimum value, and Nothing is output to the control unit 38. Amplitude controller 3
8, the amplitude control signal 131 for increasing the amplitude of the second reference frequency 132 to the second reference frequency generator 39 when the high-level reflected voltage determination signal 130 is input.
Is output, and when the low-level reflected voltage determination signal 130 is input, the amplitude control signal 1 for reducing the amplitude of the second reference frequency 132 to the second reference frequency generator 39 is output.
31 is output. Light emitting pulse modulation signal generating unit 31 for sensing
Then, the second sensing light emitting pulse signal 124 is amplitude-modulated using the second reference frequency 132 whose amplitude is controlled by the amplitude control signal 131. The output signal of the sensing light emitting pulse modulation signal generation unit 31 is the second reference frequency 132 when the second sensing light emitting pulse signal 124 is at a high level.
, And nothing is output when the level is low.

The sensing light emitting pulse modulation signal generator 31
The amplitude modulation signal 126 and the communication pulse modulation signal 101, which are the output signals of the above, are voltage-added in the signal addition section 21 and output as an addition signal 118b, and the addition signal 118b
The common light emitting unit 23 emits the common irradiation light 12 by the current adjusted by the common drive unit 22 that adjusts the current in proportion to
Emits 0.

The common irradiation light 120 is received by the on-vehicle communication device 3 and the reflected light 12 from the road surface 1 and the vehicle 2
The light is received by the light receiving unit 24 as 1. Further, the irradiation light 104 of the frequency-modulated transmission data from the in-vehicle communication device 3 is used.
Is also received by the light receiving section 24. The received signal 122 received by the light receiving unit 24 is subjected to voltage amplification while removing a stationary unnecessary DC component due to disturbance light in the common amplification unit 25.

The output signal of the common amplifying unit 25 is
At 6a, the signal is distributed to the reception signal control unit 32 and the second electric bandpass filter.

The output signal of the signal distribution unit 26a is passed through the output of the signal distribution unit 26a as it is when the second sensing light emitting pulse signal 124 is at a high level, and nothing is transmitted when it is at a low level. , Only the reception signal 123 when the second sensing light emission pulse signal 124 is emitted from the common light emitting unit 23 can be used for vehicle detection. The output signal of the reception signal control unit 32 is passed through a third electric band-pass filter 33 that passes only the frequency of the second reference frequency 132 to remove unnecessary signals. The output signal of the third electrical bandpass filter 33 is converted by a level detector 34 into a reflected voltage 127 which is a voltage proportional to the amplitude. Then, the signal comparing section 17 compares the reflected voltage 127 with a preset reference voltage to detect a vehicle.

[0040]

According to the first aspect of the present invention, the sensing light emitting pulse having a frequency higher than the frequency of the communication pulse modulation signal and the communication pulse modulation signal are added, and irradiation light is emitted according to the added voltage value. By adjusting, even if the same light emitting part is used and the sensing light emitting pulse signal and the communication pulse modulated signal are irradiated in the same direction, the effect of the sensing light emitting pulse on the received data in the vehicle-mounted communication device is reduced. Can be eliminated.

Further, by making the frequency used for frequency modulation of the transmission data of the vehicle-mounted communication device different from the frequency of the sensing light emitting pulse signal, the transmission data of the vehicle-mounted communication device and the light emission from the light-emitting portion can be received by the same light receiving unit. Even when the reflected light of the irradiation light from the vehicle or the road surface is received, it is possible to eliminate the interference between the transmission data of the on-vehicle communication device and the light emission pulse signal for sensing.

As described above, it is possible to prevent a decrease in vehicle detection performance and communication performance due to the same vehicle detection area and communication area.

Therefore, the communication with the on-vehicle communication device and the detection of the vehicle can be performed in the same area by one light-emitting unit, drive unit, light-receiving unit, and amplifying unit. Reduction and simplification of the mechanism structure are possible.

According to the second aspect of the present invention, the sensing light emitting pulse signal used for vehicle detection is set to a frequency higher than the frequency of the communication light emitting pulse modulation signal and the frequency of the transmission data of the vehicle-mounted communication device. By performing amplitude modulation using a reference frequency that is different from the frequency used for modulation,
The sensing light emission pulse and the communication pulse modulation signal can be separated on the frequency. Therefore, even if the same light emitting unit is used and the sensing light emitting pulse signal and the communication pulse modulation signal are irradiated in the same direction, the effect of the sensing light emitting pulse signal on the data received by the onboard communication device is eliminated. Can be.

Further, by making the frequency used for frequency modulation of the transmission data of the vehicle-mounted communication device different from the frequency of the sensing light emitting pulse signal, the transmission data of the vehicle-mounted communication device and the light emission from the light-emitting portion can be received by the same light receiving unit. Even when the reflected light of the irradiation light from the vehicle or the road surface is received, it is possible to eliminate the interference between the transmission data of the on-vehicle communication device and the light emission pulse signal for sensing.

As described above, it is possible to prevent a decrease in vehicle detection performance and communication performance due to the same vehicle detection area and communication area.

Also, by using a method of amplitude-modulating and amplitude-demodulating a low-frequency sensing light-emitting pulse signal on a high-frequency carrier, a signal comparing unit that performs vehicle detection processing operates at a low operating frequency. Vehicle detection processing becomes possible.

Thus, the communication with the on-board communication device and the detection of the vehicle can be performed in the same area by one light-emitting unit, drive unit, light-receiving unit, and amplifying unit. Reduction and simplification of the structure are possible. Further, the vehicle detection processing can be realized by an inexpensive circuit.

According to the third aspect of the present invention, the transmission interval of the sensing light emitting pulse signal is controlled, and the number of times of sending the sensing light emitting pulse signal is adjusted. Optimum power consumption and heat generation can be adjusted, so on routes with low traffic volume, vehicle detection is performed with low power consumption using the third sensing light emission pulse signal m with a wide pulse interval, and traffic volume is reduced. In the case of a route having a large number of routes, it is possible to use the third sensing light emitting pulse signal n having a narrow pulse interval to improve vehicle detection accuracy.

According to the fourth aspect of the present invention, the amplitude of the reference frequency used for amplitude-modulating the sensing light emission pulse signal can be automatically adjusted, so that optimum vehicle detection accuracy and optimum consumption can be achieved. It is possible to automatically adjust the power and the heat value.

[Brief description of the drawings]

FIG. 1 is a block diagram showing Embodiment 1 of an optical vehicle sensing device according to the present invention.

FIG. 2 is a block diagram showing Embodiment 2 of the optical vehicle sensing device according to the present invention.

FIG. 3 is a block diagram showing Embodiment 3 of the optical vehicle sensing device according to the present invention.

FIG. 4 is a block diagram showing Embodiment 4 of the optical vehicle sensing device according to the present invention.

FIG. 5 is a diagram for describing Embodiment 1 of the optical vehicle sensing device according to the present invention.

FIG. 6 is a diagram for explaining Embodiment 1 of the optical vehicle sensing device according to the present invention.

FIG. 7 is a diagram for describing Embodiment 1 of the optical vehicle sensing device according to the present invention.

FIG. 8 is a diagram for describing Embodiment 1 of the optical vehicle sensing device according to the present invention.

FIG. 9 is a diagram for describing Embodiment 1 of the optical vehicle sensing device according to the present invention.

FIG. 10 is a view for explaining Embodiment 2 of the optical vehicle sensing device according to the present invention.

FIG. 11 is a view for explaining Embodiment 2 of the optical vehicle sensing device according to the present invention.

FIG. 12 is a view for explaining Embodiment 2 of the optical vehicle sensing device according to the present invention.

FIG. 13 is a view for explaining Embodiment 2 of the optical vehicle sensing device according to the present invention.

FIG. 14 is a view for explaining Embodiment 2 of the optical vehicle sensing device according to the present invention.

FIG. 15 is a view for explaining Embodiment 2 of the optical vehicle sensing device according to the present invention.

FIG. 16 is a view for explaining Embodiment 2 of the optical vehicle sensing device according to the present invention.

FIG. 17 is a view for explaining Embodiment 3 of the optical vehicle sensing device according to the present invention.

FIG. 18 is a diagram for explaining Embodiment 3 of the optical vehicle sensing device according to the present invention.

FIG. 19 is a diagram for describing Embodiment 4 of the optical vehicle sensing device according to the present invention.

FIG. 20 is a block diagram showing a conventional optical vehicle sensing device.

FIG. 21 is an installation diagram of an optical vehicle sensing device.

FIG. 22 is a view for explaining a conventional optical vehicle sensing device.

FIG. 23 is a view for explaining a conventional optical vehicle sensing device.

FIG. 24 is a view for explaining a conventional optical vehicle sensing device.

[Explanation of symbols]

1 road, 2 vehicle, 3 on-board communication device, 4 transmission data generation unit, 5 communication pulse modulation signal generation unit, 6 communication drive unit, 7 communication light emitting unit, 8 communication light receiving unit,
9 Communication amplification unit, 10 Frequency demodulation unit, 11 Signal processing unit, 12 Light emitting pulse generation unit for sensing, 13 Drive unit for sensing, 14 Light emitting unit for sensing, 15 Light receiving unit for sensing, 1
6 Sensing amplifying section, 17 Signal comparing section, 18 Vehicle detecting section, 19 Traffic information calculating section, 20 First sensing light emitting pulse generating section, 21 Signal adding section, 22 Common drive section, 23 Common light emitting section, 24 Common light receiving section, 25 common amplifying section, 26 signal distribution section, 27 first electric bandpass filter, 28 second electric bandpass filter, 29 second sensing light emitting pulse generation section, 30 first
Reference frequency generator, 31 Sensing projection pulse modulation signal generator, 32 Received signal controller, 33 Third electrical bandpass filter, 34 Level detector, 35 Pulse interval controller, 36 Third sensing Light emission pulse generator,
37 signal comparison / determination section, 38 amplitude control section, 39 second
Reference frequency generator, 40 bidirectional communication area, 41
Vehicle detection area, A emitter / receiver, B controller, M optical vehicle detector.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI H04B 10/10 10/22

Claims (4)

[Claims] 1. A transmission data generation unit for generating transmission data to be transmitted to an on-vehicle communication device mounted on a vehicle, a communication pulse modulation signal generation unit for generating a communication pulse modulation signal from the transmission data, and the communication Sensing light emitting pulse generator for generating a sensing light emitting pulse signal having a higher frequency than the pulse modulation signal for sensing and used for vehicle detection, and a sensing light emitting pulse signal from the sensing light emitting pulse generator A signal adding unit for adding the communication pulse modulation signal to the communication pulse modulation signal; a light emitting unit for emitting irradiation light according to an output signal from the addition signal unit; and receiving irradiation light emitted from the light emitting unit to receive reception information. And a vehicle-mounted communication device that frequency-modulates transmission data such as destination information registered by the driver and then emits it as an infrared ray. A light receiving unit that receives the reflected light from the vehicle of the irradiation light and the irradiation light emitted from the light emitting unit and converts the reflected light into a voltage, and extracting a frequency of the sensing light emission pulse signal from the output signals of the light receiving unit. (1) extracting means, a signal comparing section for comparing an output signal of the first extracting means with a reference value, a vehicle detecting section for outputting a vehicle detecting signal based on a comparison result of the signal comparing section, and an output of the light receiving section. A second extraction unit for extracting a frequency used for frequency modulation of the transmission data of the on-vehicle communication device from the signal, a frequency demodulation unit for generating reception data from an output signal of the second extraction unit, and a frequency demodulation unit An optical vehicle sensing device, comprising: a signal processing unit that performs signal processing on data received from a vehicle. 2. A transmission data generation unit for generating transmission data to be transmitted to an on-vehicle communication device mounted on a vehicle; a communication pulse modulation signal generation unit for generating a communication pulse modulation signal from the transmission data; A sensing light emitting pulse generator for generating a sensing light emitting pulse used for detecting a vehicle having a lower frequency as compared to the pulse modulation signal, and a light emitting pulse used for modulating the sensing light emitting pulse. A reference frequency generator for generating a reference frequency which is a relatively high frequency, and a sensing light emitting pulse modulation signal generator for sending the reference frequency when the output signal of the sensing light emitting pulse generator is at a significant level. A signal adding unit that adds the output signal of the sensing light emitting pulse modulation signal generating unit and the output signal of the communication pulse modulation signal generating unit; and irradiating light by the output signal of the signal adding unit. A light-emitting unit that emits light, and a light-receiving unit that receives reflected light from the vehicle of irradiation light emitted from the on-vehicle communication device and irradiation light emitted from the light-emitting unit and converts the light into a voltage,
A receiving signal control unit that outputs an output signal of the light receiving unit when an output signal of the sensing light emitting pulse generation unit is at a significant level; and a frequency modulation of transmission data of the on-vehicle communication device among the output signals of the light receiving unit. First extracting means for extracting the frequency used in the above, second extracting means for extracting the frequency of the reference frequency from the output signal of the received signal control unit, and correspondence with the amplitude of the output signal of the second extracting means A signal comparing section for comparing the obtained voltage level with a reference voltage, a vehicle detecting section for outputting a vehicle detecting signal based on a comparison result of the signal comparing section, and a frequency demodulation for generating reception data from an output signal of the first extracting means. And a signal processing unit for performing signal processing on data received from the frequency demodulation unit. 3. The optical vehicle sensing device according to claim 2, further comprising a pulse interval control section for outputting a control signal for controlling a transmission interval of the sensing light emitting pulse. 4. A signal comparison / judgment for comparing a voltage level corresponding to the amplitude of the output signal of the second extracting means with a reference voltage and also comparing the first judgment voltage and the second judgment voltage, and outputting a judgment result. And an amplitude control unit for outputting a control signal for controlling the amplitude of a reference frequency used for modulating the light projection pulse modulation signal for sensing based on the determination result of the signal comparison determination unit. 3. The optical vehicle sensing device according to 2.