JPH10200477A - Optical transmitter-receiver - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an optical transmitter-receiver capable of executing communication with a mobile object traveling at high speed while keeping compatibility with conventional equipment by receiving an optical transmission wave modulated at two kinds of modulation speed and automatically recognizing the modulation speed of the optical transmission wave. SOLUTION: When an optical vehicle sensor 10 is installed on an expressway, down link information modulated at high speed is sent out. An on-vehicle optical transmitter-receiver 21 is provided with a 2nd modulation speed recognizing part 13 and a 2nd modulation speed switch part 17 to be correspondingly operated. When low-speed modulated down link information is inputted from a conventional vehicle sensor on a general road, high-speed modulated up link information is sent and when high-speed modulated down link information is inputted on the expressway, high-speed modulated up link information is sent. A reception view angle is extended so that this vehicle detector 10 can deal with a vehicle mounting the conventional on-vehicle optical transmitter-receiver and when such low-speed modulated up link information is received, the modulation speed of the down link is switched to low.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a general road at a speed of, for example, 70 km / h or less and a highway at a speed of, e.
The present invention relates to an optical transmission / reception apparatus that provides traffic information and the like from an optical vehicle sensor to a vehicle traveling at a distance of less than km and receives uplink information from a vehicle equipped with an optical transmission / reception unit.

[0002]

2. Description of the Related Art FIG. 7 is an overall schematic diagram of a system using a conventional optical vehicle sensor. In the figure, reference numeral 10 denotes an optical vehicle detector, which is 5.5 m above the ground at the center of the lane of a general road.
Installed in 32 is an optical transmitting / receiving device mounted on the vehicle, 3
Reference numeral 3 denotes a downlink information communication area transmitted from the optical vehicle sensor 10, reference numeral 34 denotes a sensing area for detecting a vehicle passing by the optical vehicle sensor 10, and reference numeral 35 denotes a control unit of the optical vehicle sensor 10. It is.

FIG. 8 is a block diagram of a conventional optical transmitter / receiver for mobile units. In the figure, reference numeral 1 denotes a first light transmitting unit for transmitting downlink information from the optical vehicle sensor 10;
Is the first that modulates downlink information connected to the light emitting unit 1.
A modulation unit 5 and a first processing unit connected to the modulation unit 2;
Reference numeral 6 denotes a first display unit connected to the processing unit 5, reference numeral 7 denotes a first light receiving unit that receives uplink information transmitted from the optical transceiver and converts it into a voltage, and reference numeral 8 denotes a voltage output from the light receiving unit 7. Is a first analog / digital (A / D) converter, which converts signals into "1" and "0" signals, 10 is an optical vehicle sensor, and 11 is a downlink transmitted from the optical vehicle sensor 10. A second light receiving unit that receives information and converts it into a voltage,
Reference numeral 12 designates the voltage output from the light receiving section 11 as "1",
The second analog / digital (A
/ D) a conversion unit, 15 is a second processing unit connected to the A / D conversion unit 12, 16 is a second display unit connected to the second A / D conversion unit 12, and 19 is the second processing. A modulation unit 20 connected to the unit 15 is a second light emitting unit that transmits a transmission signal from the modulation unit 19 as uplink information, and 21 is an optical transceiver.

FIG. 9 shows a conventional apparatus in which functions are further divided in detail. In the figure, 36 is a wavelength λ = 850n.
An area where only downlink information obtained by modulating m ± 50 nm at 1.0 Mbps is provided. 37 is a portion where downlink information is provided and a viewing angle of view for receiving uplink information transmitted from the optical transceiver 21. Area, 38
Is an area for providing uplink information transmitted from the optical transceiver 21 mounted on the vehicle, and a reception viewing angle for receiving downlink information transmitted from the optical vehicle sensor 10, and 39 is the optical transceiver. 21 is a transmission area of the uplink information transmitted from the communication apparatus 21.

Next, the operation will be described. The first modulator 2 shown in FIG.
As shown in FIG. 9, the communication area 33 of the optical vehicle sensor 10 for transmitting at a modulation speed of bps is, for example, approximately in the approach direction of the vehicle in order to transmit the information amount 10 kbytes twice or more to the vehicle moving at 70 km / h. 3.1 m or more is required. Therefore, the conventional optical vehicle sensor 10 secures a communication area of about 3.5 m in the approach direction of the vehicle.

On the other hand, the light received by the second light receiving section 11 through the downlink transmission areas 36 and 37 is converted into a voltage, which is converted into a signal of "1" and "0" at an arbitrary threshold. A / D conversion unit 12 performs digital conversion. Next, the digital signal output from the second A / D conversion unit 12 is read at the modulation rate of 1.0 Mbps set by the second processing unit 15, and when synchronization is established, the information amount of downlink information of 10 kbytes is changed to the second value. Display 16
And the second display section 16 displays the data.
Also, after receiving the 1.0 Mbps signal of the second A / D converter, the second processing unit 15 set at a modulation speed of 64 kbps.
The optical transmitter / receiver 21 transmits a signal modulated by the third modulation unit 19 from the modulation speed setting signal from the third unit 19 to the second light emitting unit 20 to transmit light of 850 nm in wavelength at a modulation speed of 64 kbps. Was.

[0007]

Since the conventional optical transmitter / receiver for a mobile object is constructed as described above, the communication area of the optical vehicle sensor is required to communicate with a vehicle moving at high speed. Two methods are required to shorten the transmission time by increasing the speed in the vehicle approach direction or increasing the modulation speed. However, when the communication area of the former is widened, it is necessary to increase the communication power of the optical vehicle sensor. There is a problem that the derating is shortened.

An optical vehicle sensor having a low transmission speed has already been installed on a general road, and a high-speed compatible optical transmitting / receiving device for a highway has been provided with the optical vehicle sensor having a low transmission speed. Compatibility is required. Further, as another problem to be solved by the present invention, the uplink information from the optical transmitter / receiver mounted on the vehicle corresponding to the above-mentioned optical vehicle sensor having a low transmission rate is also used in the optical vehicle sensor. There is a problem of compatibility with existing devices that must be able to receive.

Furthermore, if the modulation speed of the communication of the existing optical transmitter / receiver for mobile objects is simply increased, the optical vehicle sensor and the optical transceiver have a delay in the internal processing time. There is a problem that two-way communication is not established when the moving speed of the vehicle equipped with the device increases.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and can be installed on an ordinary road as well as on an expressway. The present invention provides a mobile object compatible optical transceiver that can receive information transmitted from a slow optical vehicle sensor and can also receive uplink information from an on-board optical transceiver compatible with the conventional optical vehicle sensor. The purpose is to:

[0011]

An optical transmission / reception apparatus according to the present invention includes a first modulation speed switching unit in an optical vehicle sensor, and two types of a first modulation unit and a second modulation unit following the first modulation speed switching unit. Unit, the light receiving system includes a first modulation speed recognition unit, and when installed on a general road, a transmission wave of 1.0 Mbps is used.
The modulation speed is set as a standard, and when it is installed in a high traveling speed place such as a highway, it is approximately doubled to 2.0 Mbps.
And a first modulation speed recognition unit for setting the modulation speed from an output signal from the first A / D conversion unit of the light receiving system. Further, the light receiving portion of the optical vehicle sensor is provided with a function of increasing the viewing angle of the uplink information reception in the vehicle approach direction from the area where the downlink information is transmitted. Also, a function of increasing the viewing angle of the downlink information reception in the forward direction of the vehicle from the area where the uplink information is transmitted is added. In addition, the optical transmitter / receiver mounted on the moving vehicle is provided with a second modulation speed recognition unit in the light receiving system so that it can receive optical signals of two types of modulation speeds from the optical vehicle sensor. , The transmission system includes a second modulation speed switching unit, and two types of third and fourth modulation units that follow the second modulation speed switching unit. Notify.

Further, the present invention includes an automatic modulation speed conversion unit for automatically detecting the modulation speed of the transmission wave transmitted from the optical vehicle sensor from the output signal from the second A / D conversion unit. Things.

The present invention also relates to a traveling speed recognition system for automatically recognizing a traveling speed of a vehicle equipped with an optical transceiver in order to automatically change a transmission speed of uplink information from an optical transceiver mounted on the vehicle. Part is provided.

Further, the present invention includes an interface unit for directly inputting a traveling speed from a vehicle equipped with an optical transceiver.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION

Embodiment 1 FIG. Hereinafter, a first embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing a configuration of a mobile object compatible optical transceiver according to the present invention. In FIG. 1, reference numeral 1 denotes a first light emitting unit for transmitting an optical signal, and 2 denotes a transmission signal having a transmission speed of 1.0 MBps. A first modulation unit for amplitude-modulating the transmission signal at 3, a second modulation unit for amplitude-modulating with a transmission signal having a transmission rate of 2.0 MBps, a first modulation speed switching unit for switching between these two types of modulation units, and a reference numeral 5 for A first processing unit 6 for controlling the first modulation speed switching unit 4, a first display unit 6 for displaying a modulation speed during transmission and reception, and reception information, and a first display unit 7 for receiving an optical transceiver mounted on a traveling vehicle. A first light-receiving unit 8 for receiving the transmitted uplink information and converting the voltage into a voltage is a first light-receiving unit 8 for converting the voltage output from the first light-receiving unit 7 into “1” and “0” signals. An analog / digital (A / D) changing unit 9 is the first A / D converting unit 8 First to recognize the modulation rate for hanging synchronization from al digital signal to the modulation rate of the received reception signal of the first light receiving portion 7
, A modulation speed recognition unit, 10 is an optical vehicle sensor, 11 is a second light receiving unit that receives downlink information transmitted from the optical vehicle sensor 10 and converts it into a voltage, and 12 is a second light receiving unit. The voltages output from the light receiving unit 11 are "1" and "0".
Second analog / digital (A / D) converting to a signal of
The conversion unit 13 is used to recognize a modulation speed for synchronizing the modulation speed of the reception signal received by the second light receiving unit 11 from the digital signal from the second A / D conversion unit 12. Is an input unit for selecting one of the two types of modulation speeds of the first modulation unit 2 and the second modulation unit 3, and 15 is a unit for selecting a setting signal from the input unit 14. For example, 1.0MBPS synchronization detection for received signal
And 2.0 MBPS alternately, and the second processing unit 16 for detecting the synchronization pattern for the signal from the second modulation speed recognition unit 13 and detecting the modulation speed. A second display unit 17 for displaying the modulation speed of the received signal detected by the second processing unit 15 and the received information, and further displaying the modulation speed of the transmission signal, is transmitted by the second processing unit 15. A second modulation speed switching unit that is set for the setting of the modulation speed, 18 is a third modulation unit that sets amplitude modulation with the modulation speed from the second modulation speed switching unit 17, and 19 is the second modulation speed switching unit. A fourth modulation unit for setting the amplitude modulation with the modulation speed from the modulation speed switching unit 17 of the third embodiment;
And a second light projecting unit 21 for modulating light with the signal of the fourth modulating unit 19 and transmitting the light, and 21 is an optical transceiver.

Next, the operation will be described. In FIG. 2, reference numeral 22 denotes an area where downlink information transmitted from the optical vehicle sensor 10 is transmitted, and reference numeral 23 denotes an area where downlink information transmitted from the optical vehicle sensor 10 is transmitted and the optical transmission / reception. A region for receiving the uplink information transmitted from the optical transmitter, a region for receiving the uplink information transmitted from the optical transceiver 21, and a region for receiving the downlink information transmitted from the optical vehicle sensor 10. An area 26 receives the downlink information transmitted from the optical vehicle sensor 10 and an area receives the downlink information transmitted from the optical vehicle sensor 10, and 27 denotes the optical vehicle sensor. Is an area for receiving downlink information transmitted from the detector 10, and the viewing angle of reception of the uplink information of the optical vehicle detector 10 is down. It has a wide feature in approach direction of the vehicle than the transmission angle of the link information. Further, the optical transmitter / receiver 21 is characterized in that the viewing angle of the downlink information reception is wider in front of the vehicle than the uplink information transmission angle. As a result, both the optical vehicle sensor 10 and the optical transceiver 21 can absorb the delay time caused by switching the modulation speed without affecting information provision.

In FIG. 3, reference numerals 28a to 28c denote sampling rates at which the output signal from the second A / D converter 12 of the second modulation speed recognizer 13 is sampled. 28
If a is a sampling rate A for sampling the modulation speed of the first modulation unit 2 and 28b is a sampling rate B for sampling the modulation speed of the second modulation unit 3, AB is selected from the input unit 14 and the second is selected. The output signal from the A / D conversion unit 12 is synchronized, and the second processing unit 15 performs processing after the synchronization.

Thus, the first modulator 2 and
The modulation speed of the second modulator 3 is set to, for example, 1.0 Mbps.
When the speed is set to about twice as high as 2.0 Mbps, communication can be performed corresponding to the traveling speed of the moving vehicle up to about twice. That is, since the conventional optical transceiver has a low transmission speed in a limited narrow communication area, it may not be possible to communicate with a vehicle traveling at a high traveling speed, for example, a vehicle traveling at a speed of 70 km / h or more. Further, in order to widen a communication area for communicating with a vehicle moving at a high speed, it is necessary to use a large number of LEDs for the first light projecting unit 1, which leads to an increase in the size of the optical vehicle sensor 10. The same can be said for the second light projecting unit 20 of the optical transceiver 21. Therefore, according to the present invention, the optical vehicle sensor 10 can be reduced in size, and the optical transceiver 21 can be reduced in size.
Since communication with a vehicle moving at high speed can be performed without using the communication device, cost can be reduced.

Embodiment 2 In the second embodiment shown in FIG. 4, for example, 1.0 MBPS and 2.0 MB
This shows a case where an automatic modulation speed conversion unit 29 for alternately switching MBPS is connected. In the first embodiment shown in FIG. 1, the signal output from the second A / D converter 12 is subjected to time division timing indicated by 28c in FIG. The data is transmitted to the unit 13 and sampled at a mixture of the sampling rates AB. From the synchronized sampling rate, the first
The modulation speed modulated by the modulation unit 2 or the second modulation unit 3 is automatically recognized. The recognized modulation speed signal is received from the second modulation speed recognition unit 13 and the transmission signal from the automatic modulation speed conversion unit 29 is used for the second processing unit 1.
5 automatically sets the modulation speed of the received downlink information. In the case of the first embodiment, it is conceivable that communication may be disabled due to a human setting error, but such an error can be eliminated. Further, since the input unit 14 can be omitted, the device configuration can be simplified, and the cost can be reduced.

Embodiment 3 In the third embodiment shown in FIG. 5, a traveling speed recognition unit 30 for automatically detecting the traveling speed of the own vehicle by using a Doppler system such as a radio wave is added to the optical transceiver 21. The traveling speed recognition unit 30 automatically detects the speed of the vehicle. For example, when the traveling speed is 70 km / h or more, the traveling speed recognition unit 30 notifies the input unit 14 that the vehicle is traveling at a high speed. The synchronization detection speed of the second modulation speed recognition unit 13 is set according to the speed of the traveling vehicle, for example, if the traveling speed is 70 km / h or more, the synchronization detection speed is set to 2.0 MBPS, and the second processing unit 15 In contrast, the transmission speed of uplink information transmission is set to 12
Information for setting to 8 kBPS is transmitted. The second processing unit 15 according to the transmission speed of the uplink information
Transmits a modulation speed signal to the second modulation speed switching unit 17, selects the third modulation unit 18 and the fourth modulation unit 19 according to the traveling speed, and transmits the uplink information of the selected modulation speed. The light is transmitted from the second light projecting unit 20. If the detected traveling speed is 70 km / h or less, the input unit 14 is notified that the vehicle is traveling at a low speed, and the synchronization detection speed of the second modulation speed recognition unit 13 is synchronized according to the speed of the traveling vehicle. At the same time as setting the detection speed to 1.0 MBPS, information for setting the transmission speed of the uplink information transmission to 64 kBPS is also sent to the second processing unit 15. According to the transmission rate of the uplink information, the second
A modulation speed signal is transmitted from the processing unit 15 to the second modulation speed switching unit 17, and the third modulation unit 18 and the fourth modulation unit 19 are selected according to the traveling speed. Uplink information is transmitted from the second light emitting unit 20. In the optical vehicle sensor 10, the optical transceiver 2
Receiving the uplink information transmitted from the first
The transmission speed of the uplink information from the vehicle is recognized by the modulation speed recognition unit 9 of. The first processing unit 5 sends a modulation speed setting signal to the first modulation speed switching unit 4. The first modulation speed switching unit 4 selects the first modulation unit 2 or the second modulation unit 3 according to the setting signal. The downlink information is transmitted from the first light emitting unit 1 according to the selected modulation speed. In the case of the first embodiment, it is conceivable that communication may be disabled due to a human setting error, but such an error can be eliminated. Also,
Since the manual input unit of the input unit 14 can be omitted,
The apparatus configuration can be simplified, and the cost can be reduced. Further, on a general road, the optical transceiver 2
For example, even when the vehicle equipped with the vehicle 1 travels at a speed of 70 km / h or more, the transmission speed of the uplink information is automatically changed to enable the two-way communication with the optical vehicle sensor 10.

Embodiment 4 FIG. In the embodiment shown in FIG. 6, the running speed recognition unit 30 is replaced with an I / F (interface) unit 31 that allows direct input of speed information such as the rotation speed of a tire from a vehicle. The I / F section 31
Detects the traveling speed from the speed information corresponding to the vehicle, and performs high-speed modulation setting on the input unit 14 when the traveling speed reaches, for example, 70 km / h or more. In the case of the first embodiment, it is conceivable that communication may be disabled due to a human setting error, but such an error can be eliminated.
Further, since the manual input unit of the input unit 14 can be omitted, the configuration of the apparatus can be simplified, and the cost can be reduced. Further, even when a vehicle equipped with the optical transceiver 21 runs on a general road at, for example, 70 km / h or more, the transmission speed of the uplink information can be changed to enable two-way communication with the optical vehicle sensor 10. .

[0022]

Since the present invention is configured as described above, it has the following effects.

The transmission waves of light modulated at two kinds of modulation speeds are received, enabling communication when the moving body is running at high speed, and maintaining compatibility with a conventional optical vehicle sensor.

By automatically recognizing the modulation speed of the transmission wave of light, it is possible to eliminate setting errors caused by manual input when traveling on a general road, and to simplify the input section and reduce costs.

By adding the device, the running speed is automatically detected by Doppler speed detection or the like, so that the running speed of the vehicle equipped with the optical transceiver is automatically detected. be able to.

Since the information of the traveling speed is directly received from the vehicle equipped with the optical transceiver, the configuration of the apparatus can be simplified and the cost can be reduced.

[Brief description of the drawings]

FIG. 1 is a configuration block diagram of a high-speed mobile object compatible optical transmission / reception device showing a first embodiment of the present invention.

FIG. 2 is an operation explanatory diagram of the first embodiment of the present invention.

FIG. 3 is an operation explanatory diagram of the first embodiment of the present invention.

FIG. 4 is a block diagram showing a configuration of an optical transceiver for a high-speed mobile object according to a second embodiment of the present invention.

FIG. 5 is a block diagram showing a configuration of an optical transceiver for a high-speed mobile object according to a third embodiment of the present invention.

FIG. 6 is a block diagram showing a configuration of an optical transmission / reception apparatus compatible with a high-speed moving object according to a fourth embodiment of the present invention.

FIG. 7 is an overall overview using a conventional optical vehicle sensor.

FIG. 8 is a block diagram showing a configuration of a conventional high-speed mobile object compatible optical transceiver.

FIG. 9 is an explanatory diagram of a conventional operation.

[Explanation of symbols]

REFERENCE SIGNS LIST 1 first light emitting section, 2 first modulation section, 3 second modulation section, 4 first modulation speed switching section, 5 first processing section, 6
1st display section, 7 1st light receiving section, 8 1st analog / digital conversion section, 9 1st modulation speed recognition section, 10
Optical vehicle detector, 11 second light receiving unit, 12 second
13 analog-to-digital conversion unit, 13 second modulation speed recognition unit, 14 input unit, 15 second processing unit, 16 second
Display section, 17 second modulation speed switching section, 18 third modulation section, 19 fourth modulation section, 20 second light projection section, 2
1 optical transceiver, 22 downlink information transmission area, 2
3 downlink information transmission area + uplink information reception area, 24 uplink information reception area, 25 downlink information reception area, 26 downlink information reception area +
Uplink information transmission area, 27 Uplink information transmission area, 28 Modulation speed detection synchronization signal, 29 Automatic modulation speed conversion section, 30 Running speed recognition section, 31 Interface section, 32 Optical transmission / reception section, 33 Downlink information transmission area, 34 sensing area, 35 control section, 36 downlink information transmission area, 37 downlink information transmission area + uplink information reception area, 38 downlink information reception area + uplink information transmission area, 35 uplink information transmission area.

Claims (4)

[Claims] 1. A first light emitting unit for transmitting an optical signal, a first modulating unit for modulating the amplitude of the transmission signal, and a second modulating unit for amplitude modulating the transmission signal at a different modulation speed from the first modulating unit. A modulation unit, a first modulation speed switching unit that switches the first and second modulation units, a first processing unit that transmits a switching signal to the first modulation speed switching unit, a modulation speed of a transmission signal, and reception data. A first display unit that displays the information, receives the uplink information transmitted from the optical transmitting / receiving device mounted on the traveling vehicle, converts the received information into a voltage, and converts the downlink information transmitted from the first light emitting unit into a voltage. A first light receiving unit having a wider light receiving viewing angle in the approach direction than the transmission angle with respect to the vehicle approach direction, and a first light receiving unit for converting a voltage output from the first light receiving unit into a signal of “1” or “0”; Analog / digital converter and first A / D converter An optical vehicle sensor comprising: a first modulation speed recognition unit connected to the optical sensor; a second light receiving unit for receiving downlink information transmitted from the optical vehicle sensor and converting the received downlink information into a voltage; A second analog / digital converter for converting a voltage output from the second light receiving unit into a signal of "1" and "0", and synchronizing a signal transmitted from the second A / D converter with the second analog / digital converter A second modulation speed recognition unit for recognizing a modulation speed, an input unit for selecting one of two types of modulation speeds of the first modulation unit and the second modulation unit, the input unit and the second modulation A second processing unit for transmitting a modulation speed switching signal with a signal from the speed recognition unit, a second display unit for displaying the modulation speed of the transmission / reception signal and received data, and a modulation speed switching signal from the second processing unit. A second modulation speed switching unit for transmitting a modulation speed switching signal; A third modulation unit that modulates the transmission signal at a modulation speed appropriately determined by a signal from the modulation speed switching unit, a fourth modulation unit that modulates the transmission signal at a modulation speed different from the third modulation speed, 3, a second light emitting unit for transmitting the modulated signal from the fourth modulating unit as light, and a transmission angle of the uplink information transmitted from the second light emitting unit with respect to the forward direction of the vehicle. An optical transceiver, comprising: the second light receiving unit having a wide light receiving viewing angle in a forward direction; and an optical transceiver mounted on a vehicle. 2. An automatic modulation speed conversion unit is added to an input unit for selecting and inputting one of two types of modulation speeds of the optical transceiver, and the modulation speed of downlink information transmitted from an optical vehicle sensor is adjusted. The modulation rates of the downlink information are detected at two types of modulation rates in a time-division manner corresponding to the modulation rates of the first modulation section and the second modulation section, and fixed to one of the modulation rates when synchronization is established. The optical transceiver according to claim 1, wherein the optical transceiver performs processing. 3. An optical transmission / reception device, further comprising a traveling speed recognition unit for detecting a speed of a traveling vehicle, wherein a modulation speed of uplink information transmitted from the optical transmission / reception device is automatically made to correspond to a vehicle speed. 2. The method according to claim 1, wherein the change is performed.
Or the optical transmitting and receiving device according to 2. 4. An interface unit for receiving a speed signal directly from a traveling vehicle is added, and a modulation speed of uplink information transmitted from the optical transceiver is automatically changed in accordance with a speed of the vehicle. The optical transceiver according to claim 1, 2 or 3.