CA1130405A - Device for controlling a traffic-light installation - Google Patents
Device for controlling a traffic-light installationInfo
- Publication number
- CA1130405A CA1130405A CA317,405A CA317405A CA1130405A CA 1130405 A CA1130405 A CA 1130405A CA 317405 A CA317405 A CA 317405A CA 1130405 A CA1130405 A CA 1130405A
- Authority
- CA
- Canada
- Prior art keywords
- modulation
- control
- antenna
- vehicle
- traffic
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Classifications
-
- G—PHYSICS
- G08—SIGNALLING
- G08G—TRAFFIC CONTROL SYSTEMS
- G08G1/00—Traffic control systems for road vehicles
- G08G1/123—Traffic control systems for road vehicles indicating the position of vehicles, e.g. scheduled vehicles; Managing passenger vehicles circulating according to a fixed timetable, e.g. buses, trains, trams
-
- G—PHYSICS
- G08—SIGNALLING
- G08G—TRAFFIC CONTROL SYSTEMS
- G08G1/00—Traffic control systems for road vehicles
- G08G1/07—Controlling traffic signals
- G08G1/087—Override of traffic control, e.g. by signal transmitted by an emergency vehicle
Abstract
ABSTRACT
The invention relates to a device for controlling a traffic-light installation. To that end, the vehicle is provided with an antenna radiating in the direction of travel in addition to the position-finding transmitting/receiving antenna radiating at right angles to the direction of travel. The position-finding devices on the vehicle are designed in such a manner that information (enquiry messages) can be transmitted to the traffic-light receiving devices simultaneously with, or in the trans-mitting pauses between, measurements for position-finding. The device according to the invention may be used for traffic-control systems.
The invention relates to a device for controlling a traffic-light installation. To that end, the vehicle is provided with an antenna radiating in the direction of travel in addition to the position-finding transmitting/receiving antenna radiating at right angles to the direction of travel. The position-finding devices on the vehicle are designed in such a manner that information (enquiry messages) can be transmitted to the traffic-light receiving devices simultaneously with, or in the trans-mitting pauses between, measurements for position-finding. The device according to the invention may be used for traffic-control systems.
Description
~13~4(~S
The invention relates to a device for controlling a traffic-light installation by means of vehicles equipped with devices for automatic locating (position-finding).
The continual increase in the use of motor-vehicles, and therefore in inner-city traffic, means that public-service vehicles, such as buses and streetcars, must function in congested areas under increasingly difficult conditions. However, these vehicles must be attractive to the customers and must operate efficiently. There are also demands for higher speeds, more frequent service, and adherence to schedules. Effective operation of inner-city traffic therefore requires that it be possible to over-ride the green phases of the traffic lights, and this requirement becomes even more urgent where rescue and police vehicles are involved.
In the case of streetcars, control of the green phase is achieved through the tracks or the overhead wires. In the case of buses, induction loops are located a few hundred metres before the intersection. One loop may be used merely to indicate the presence of a bus, or two loops to measure the length of a bus, although this may lead to incorrect indications when trucks of the same size as the buses are travelling along the same route. This problem may be overcome by using a transmitter on the bus.
But this still means considerable expense in installing cables from the loops to the traffic lights.
Other systems overcome this disadvantage by transmitting the message from the vehicle directly~ and through the air, to a receiver on the traffic light, for example by radio, ultrasonics, or infra-red radiation.
It is the purpose of the invention to provide a simple device :113~?4~5 for controlling a traffic-light installation by means of vehicles equipped with devices for automatic location (position-finding).
Position-finding or locating systems for vehicles travelling along fixed routes function by comparing two criteria, one being the predetermined distance between the starting point and a position-indicating transmitter, while the other is the distance between the starting point and the said position-indicating transmitter, as indicated by the vehicle odometer. Since the control-room is aware of the exact distance between the starting point and the location of each position-indicating transmitter, a computer can determine, from the distance-information received, any deviation from the nominal value and can apply a suitable correction factor to any further information from the relevant vehicle. This results in a high degree of position-finding accuracy. A system of this kind, for transmitting infor-mation between position-indicating transmitters and vehicles, uses a reading unit on each vehicle and answering units (position-indicating transmitters) arranged at specific intervals along the route.
According to one aspect of the invention, there is provided in an installation for the control of a traffic light system from a vehicle, the combination of means carried by the vehicle for supplying information for automatic determination of position, i.e. bearing determination, a first directional antenna for transmission/reception, carried by the vehicle for transmission of such bearing information and having its transmission direction oriented essentially perpendicular to the direction of travel of the vehicle, a second directional antenna carried by the vehicle and oriented in the direc-tion of travel of the vehicle for transmission of transfer messages or commands $or the control of lights of such a traffic light system, means for producing carrier waves, means for modulating said carrier waves, said means for modu-lation is adapted to provide two types of modulated signals which are ortho-. ~
~13~4QS
gonal to one another, one for the modulat;on of bearing information and theother for the modulation of transfer messages or commands, change-over switch means selectively connecting said means for modulation to said first antenna over a shunt means or to said second antennal and control means connected to said change-over switch means and said means for modulation for selectively controlling the type o:f modulation utilized and the antenna employed for a selected transmission.
According to another aspect of the invention there is provided, in a vehicular location system with a first directional antenna for receiving or transmitting vehicular location related information connected to means for demodulating received vehicular location related messages and a second directional antenna for transmitting traffic light control messages connected to means for modulation of a carrier signal with said traffic light control message, an improvement wherein: said first directional antenna is oriented substantially perpendicular to the direction of vehicular travel and said second directional antenna is oriented substantially along the direction of vehicular travel; and said means for modulating has a control input port and is adapted to generate a modulated signal with a first or second type of modulation upon sensing a first electronic signal generated by a control means based on whether a vehicular location message or a traffic signal con-trol message is to be transmitted; and means for connecting said generated modulated signal to either the first or the second antenna upon sensing a second electronic signal generated by said control means based on whether a vehicular location message or a traffic signal control message is to be trans-mitted; whereby said transmitted vehicular location related messages and said transmitted traffic light control related messages are orthogonal to one another .
-2a-113C~VS
According to one advantageous configuration of the object of the application, an antenna change-over switch is provided, the outputs from which may be connected selectively to the antenna for traffic-light control or through a branching circuit to the position-finding system, the said change-over switch being triggered by a control circuit in such a manner that it is connected to the relevant output according to the information supplied to its input in the form of modulation signals for the transmission of relevant information (position-finding information or enquiry messages).
It is desirable for enquiry messages to be modulated on a carrier in a modulating procedure which is at right angles to the position-finding system.
According to still another advantageous configuration of the object of the invention, provision is made for additional position-selective information to be transmitted to other receivers installed along the route These may be, for example, arrival information which is transmitted to an arrival indicator at bus stops.
The invention is explained hereinafter in greater detail, in con-junction with the examples of embodiment illustrated in the drawing attached hereto, wherein: Figure 1 is a block wiring diagram of the position-finding system with combined traffic-light control; Figure 2 shows a bus in street operation, with the necessary position-finding and control devices on the bus and along the edge of the street.
The top row in the block diagram in Figure 1 contains the elements of the position-finding system. Connected to one side of branching circuit 1 is transmitting/receiving antenna 2 which is aligned with antenna 3 of 1~3(~4~:~5 answering unit 4 (the position-indicating transmitter). Connected to the other side of branching circuit 1 are a frequency-converter 5, a unit 6 for analog signal processing, and a unit 7 for digital signal processing. Data are released by digital signal processor 7.
The position-finding system is extended by devices for traffic-light control (APS) comprising an antenna-change-over switch 8, one output of which is connected to branching circuit 1, while a second output is con-nected to additional transmitting antenna 12 for the traffic-light control.
Antenna 12 is aligned with antenna 13 on traffic-light receiver 14. One input to antenna-change-over switch 8 is connected to a change-over modu-lator 9 to which a fixed-frequency oscillator 10, with a frequency f = 2.45 GHz, for example, is connected. The two outputs from a control switch 11 are connected to antenna-change-over switch 8 and modulator 9.
This position-finding system is expanded in such a manner that enquiry messages can also be suitably modulated and transmitted. In this connection, provision is made for selecting a modulating procedure at right angles to the position-finding system, which ensures optimal interference -decoupling of the two functions, even when several vehicles are in use simultaneously. Thus, if for instance, the position-finding function is being carried out with amplitude shift-keying (ASK), then frequency shift-keying (FSK) is used for the enquiry message. Modulator 9 is controlled and changed over by control switch 11, to one input I of which information regarding the type of transmission is fed, while the APS message is fed to second input II thereof. Either an ASK signal (an amplitude-modulated, low-distortion-factor signal) is fed~ through simultaneously triggered s40S
antenna-change-over switch 8, through branching circuit 1, to the position-finding device, or an FSK (frequency-modulated) signal is fed to transmitting antenna 12 which transmits a message to traffic-light receiver 14. Provision is also made to provide the individual sections along the route with mark-ings (identification), so that incoming messages are evaluated only by the traffic lights for which they are intended.
Antenna-change-over switch 8, which may also be omitted if necessary, is an advantageous way of providing further decoupling of the position-finding and control areas of the circuit.
Figure 2 shows a bus in street operation, the roof of which carries a transmitting/receiving antenna 2 for the position-finding system (the traffic-control system), with a direction of radiation at right angles to the direction of travel, and an additional antenna 12 radiating in the direction of travel. Transmitting/receiving antenna 2 is in radio com-munication with an answering unit 4 (a position-indication transmitter) secured to a light pole 20 at the side of the street. Antenna 12 radiates to receiver 14 on traffic-light 22, through which additional control of the traffic-light installation is carried out.
The invention relates to a device for controlling a traffic-light installation by means of vehicles equipped with devices for automatic locating (position-finding).
The continual increase in the use of motor-vehicles, and therefore in inner-city traffic, means that public-service vehicles, such as buses and streetcars, must function in congested areas under increasingly difficult conditions. However, these vehicles must be attractive to the customers and must operate efficiently. There are also demands for higher speeds, more frequent service, and adherence to schedules. Effective operation of inner-city traffic therefore requires that it be possible to over-ride the green phases of the traffic lights, and this requirement becomes even more urgent where rescue and police vehicles are involved.
In the case of streetcars, control of the green phase is achieved through the tracks or the overhead wires. In the case of buses, induction loops are located a few hundred metres before the intersection. One loop may be used merely to indicate the presence of a bus, or two loops to measure the length of a bus, although this may lead to incorrect indications when trucks of the same size as the buses are travelling along the same route. This problem may be overcome by using a transmitter on the bus.
But this still means considerable expense in installing cables from the loops to the traffic lights.
Other systems overcome this disadvantage by transmitting the message from the vehicle directly~ and through the air, to a receiver on the traffic light, for example by radio, ultrasonics, or infra-red radiation.
It is the purpose of the invention to provide a simple device :113~?4~5 for controlling a traffic-light installation by means of vehicles equipped with devices for automatic location (position-finding).
Position-finding or locating systems for vehicles travelling along fixed routes function by comparing two criteria, one being the predetermined distance between the starting point and a position-indicating transmitter, while the other is the distance between the starting point and the said position-indicating transmitter, as indicated by the vehicle odometer. Since the control-room is aware of the exact distance between the starting point and the location of each position-indicating transmitter, a computer can determine, from the distance-information received, any deviation from the nominal value and can apply a suitable correction factor to any further information from the relevant vehicle. This results in a high degree of position-finding accuracy. A system of this kind, for transmitting infor-mation between position-indicating transmitters and vehicles, uses a reading unit on each vehicle and answering units (position-indicating transmitters) arranged at specific intervals along the route.
According to one aspect of the invention, there is provided in an installation for the control of a traffic light system from a vehicle, the combination of means carried by the vehicle for supplying information for automatic determination of position, i.e. bearing determination, a first directional antenna for transmission/reception, carried by the vehicle for transmission of such bearing information and having its transmission direction oriented essentially perpendicular to the direction of travel of the vehicle, a second directional antenna carried by the vehicle and oriented in the direc-tion of travel of the vehicle for transmission of transfer messages or commands $or the control of lights of such a traffic light system, means for producing carrier waves, means for modulating said carrier waves, said means for modu-lation is adapted to provide two types of modulated signals which are ortho-. ~
~13~4QS
gonal to one another, one for the modulat;on of bearing information and theother for the modulation of transfer messages or commands, change-over switch means selectively connecting said means for modulation to said first antenna over a shunt means or to said second antennal and control means connected to said change-over switch means and said means for modulation for selectively controlling the type o:f modulation utilized and the antenna employed for a selected transmission.
According to another aspect of the invention there is provided, in a vehicular location system with a first directional antenna for receiving or transmitting vehicular location related information connected to means for demodulating received vehicular location related messages and a second directional antenna for transmitting traffic light control messages connected to means for modulation of a carrier signal with said traffic light control message, an improvement wherein: said first directional antenna is oriented substantially perpendicular to the direction of vehicular travel and said second directional antenna is oriented substantially along the direction of vehicular travel; and said means for modulating has a control input port and is adapted to generate a modulated signal with a first or second type of modulation upon sensing a first electronic signal generated by a control means based on whether a vehicular location message or a traffic signal con-trol message is to be transmitted; and means for connecting said generated modulated signal to either the first or the second antenna upon sensing a second electronic signal generated by said control means based on whether a vehicular location message or a traffic signal control message is to be trans-mitted; whereby said transmitted vehicular location related messages and said transmitted traffic light control related messages are orthogonal to one another .
-2a-113C~VS
According to one advantageous configuration of the object of the application, an antenna change-over switch is provided, the outputs from which may be connected selectively to the antenna for traffic-light control or through a branching circuit to the position-finding system, the said change-over switch being triggered by a control circuit in such a manner that it is connected to the relevant output according to the information supplied to its input in the form of modulation signals for the transmission of relevant information (position-finding information or enquiry messages).
It is desirable for enquiry messages to be modulated on a carrier in a modulating procedure which is at right angles to the position-finding system.
According to still another advantageous configuration of the object of the invention, provision is made for additional position-selective information to be transmitted to other receivers installed along the route These may be, for example, arrival information which is transmitted to an arrival indicator at bus stops.
The invention is explained hereinafter in greater detail, in con-junction with the examples of embodiment illustrated in the drawing attached hereto, wherein: Figure 1 is a block wiring diagram of the position-finding system with combined traffic-light control; Figure 2 shows a bus in street operation, with the necessary position-finding and control devices on the bus and along the edge of the street.
The top row in the block diagram in Figure 1 contains the elements of the position-finding system. Connected to one side of branching circuit 1 is transmitting/receiving antenna 2 which is aligned with antenna 3 of 1~3(~4~:~5 answering unit 4 (the position-indicating transmitter). Connected to the other side of branching circuit 1 are a frequency-converter 5, a unit 6 for analog signal processing, and a unit 7 for digital signal processing. Data are released by digital signal processor 7.
The position-finding system is extended by devices for traffic-light control (APS) comprising an antenna-change-over switch 8, one output of which is connected to branching circuit 1, while a second output is con-nected to additional transmitting antenna 12 for the traffic-light control.
Antenna 12 is aligned with antenna 13 on traffic-light receiver 14. One input to antenna-change-over switch 8 is connected to a change-over modu-lator 9 to which a fixed-frequency oscillator 10, with a frequency f = 2.45 GHz, for example, is connected. The two outputs from a control switch 11 are connected to antenna-change-over switch 8 and modulator 9.
This position-finding system is expanded in such a manner that enquiry messages can also be suitably modulated and transmitted. In this connection, provision is made for selecting a modulating procedure at right angles to the position-finding system, which ensures optimal interference -decoupling of the two functions, even when several vehicles are in use simultaneously. Thus, if for instance, the position-finding function is being carried out with amplitude shift-keying (ASK), then frequency shift-keying (FSK) is used for the enquiry message. Modulator 9 is controlled and changed over by control switch 11, to one input I of which information regarding the type of transmission is fed, while the APS message is fed to second input II thereof. Either an ASK signal (an amplitude-modulated, low-distortion-factor signal) is fed~ through simultaneously triggered s40S
antenna-change-over switch 8, through branching circuit 1, to the position-finding device, or an FSK (frequency-modulated) signal is fed to transmitting antenna 12 which transmits a message to traffic-light receiver 14. Provision is also made to provide the individual sections along the route with mark-ings (identification), so that incoming messages are evaluated only by the traffic lights for which they are intended.
Antenna-change-over switch 8, which may also be omitted if necessary, is an advantageous way of providing further decoupling of the position-finding and control areas of the circuit.
Figure 2 shows a bus in street operation, the roof of which carries a transmitting/receiving antenna 2 for the position-finding system (the traffic-control system), with a direction of radiation at right angles to the direction of travel, and an additional antenna 12 radiating in the direction of travel. Transmitting/receiving antenna 2 is in radio com-munication with an answering unit 4 (a position-indication transmitter) secured to a light pole 20 at the side of the street. Antenna 12 radiates to receiver 14 on traffic-light 22, through which additional control of the traffic-light installation is carried out.
Claims (2)
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:
1. In an installation for the control of a traffic light system from a vehicle, the combination of means carried by the vehicle for supplying information for automatic determination of position, i.e. bearing determin-ation, a first directional antenna for transmission/reception, carried by the vehicle for transmission of such bearing information and having its transmission direction oriented essentially perpendicular to the direction of travel of the vehicle, a second directional antenna carried by the vehicle and oriented in the direction of travel of the vehicle for transmission of transfer messages or commands for the control of lights of such a traffic light system, means for producing carrier waves, means for modulating said carrier waves, said means for modulation is adapted to provide two types of modulated signals which are orthogonal to one another, one for the modulation of bearing information and the other for the modulation of transfer messages or commands, change-over switch means selectively connecting said means for modulation to said first antenna over a shunt means or to said second antenna, and control means connected to said change-over switch means and said means for modulation for selectively controlling the type of modulation utilized and the antenna employed for a selected transmission.
2. In a vehicular location system with a first directional antenna for receiving or transmitting vehicular location related information connect-ed to means for demodulating received vehicular location related messages and a second directional antenna for transmitting traffic light control messages connected to means for modulation of a carrier signal with said traffic light control message, an improvement wherein: said first directional antenna is oriented substantially perpendicular to the direction of vehicular travel and said second directional antenna is oriented substantially along the direction of vehicular travel;and said means for modulating has a control input port and is adapted to generate a modulated signal with a first or second type of modulation upon sensing a first electronic signal generated by a control means based on whether a vehicular location message or a traffic signal control message is to be transmitted; and means for connecting said generated modulated signal to either the first or the second antenna upon sensing a second electronic signal generated by said control means based on whether a vehicular location message or a traffic signal control message is to be transmitted; whereby said transmitted vehicular location related messages and said transmitted traffic light control related messages are orthogonal to one another.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DEP2754024.5 | 1977-12-05 | ||
| DE2754024A DE2754024C3 (en) | 1977-12-05 | 1977-12-05 | Device for controlling a traffic light system |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1130405A true CA1130405A (en) | 1982-08-24 |
Family
ID=6025299
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA317,405A Expired CA1130405A (en) | 1977-12-05 | 1978-12-05 | Device for controlling a traffic-light installation |
Country Status (11)
| Country | Link |
|---|---|
| EP (1) | EP0002470A1 (en) |
| JP (2) | JPS54100300A (en) |
| AT (1) | AT369176B (en) |
| AU (1) | AU526019B2 (en) |
| CA (1) | CA1130405A (en) |
| DE (1) | DE2754024C3 (en) |
| DK (1) | DK548978A (en) |
| ES (1) | ES475730A1 (en) |
| FI (1) | FI783710A (en) |
| IT (1) | IT1100513B (en) |
| NO (1) | NO146793C (en) |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE3014928C2 (en) * | 1980-04-18 | 1991-12-12 | Licentia Patent-Verwaltungs-Gmbh, 6000 Frankfurt | Arrangement for detecting the location of a vehicle |
| DE3016480A1 (en) * | 1980-04-29 | 1981-11-05 | Licentia Patent-Verwaltungs-Gmbh, 6000 Frankfurt | Determining location of vehicle along known route - using variable integration factor selected by place code and pulse generator in vehicle |
| DE3130705A1 (en) * | 1981-08-03 | 1983-02-17 | Siemens AG, 1000 Berlin und 8000 München | Arrangement for controlling a traffic light system by means of vehicles |
| DE202007018303U1 (en) * | 2007-10-15 | 2008-07-31 | Siemens Aktiengesellschaft | Traffic light signals |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS503598A (en) * | 1973-05-14 | 1975-01-14 | ||
| US3940630A (en) * | 1974-10-21 | 1976-02-24 | Mcdonnell Douglas Corporation | Vehicle locator |
| JPS51102793A (en) * | 1975-03-07 | 1976-09-10 | Nippon Electric Co | |
| SE395555C (en) * | 1975-04-04 | 1979-08-02 | Almex Ab | DEVICE FOR REGISTRATION OF FOREMALS AND FOR TRANSFER OF ANY ADDITIONAL INFORMATION FROM THE REGISTRATION |
-
1977
- 1977-12-05 DE DE2754024A patent/DE2754024C3/en not_active Expired
-
1978
- 1978-11-20 AT AT0827678A patent/AT369176B/en not_active IP Right Cessation
- 1978-11-20 NO NO783903A patent/NO146793C/en unknown
- 1978-12-01 IT IT30444/78A patent/IT1100513B/en active
- 1978-12-01 EP EP78101503A patent/EP0002470A1/en not_active Ceased
- 1978-12-04 FI FI783710A patent/FI783710A/en unknown
- 1978-12-04 AU AU42158/78A patent/AU526019B2/en not_active Expired
- 1978-12-04 DK DK548978A patent/DK548978A/en not_active Application Discontinuation
- 1978-12-05 JP JP14974878A patent/JPS54100300A/en active Pending
- 1978-12-05 ES ES475730A patent/ES475730A1/en not_active Expired
- 1978-12-05 CA CA317,405A patent/CA1130405A/en not_active Expired
-
1983
- 1983-02-28 JP JP1983027307U patent/JPS5922638Y2/en not_active Expired
Also Published As
| Publication number | Publication date |
|---|---|
| JPS58167995U (en) | 1983-11-09 |
| FI783710A (en) | 1979-06-06 |
| DK548978A (en) | 1979-08-14 |
| ES475730A1 (en) | 1979-05-01 |
| IT7830444A0 (en) | 1978-12-01 |
| AT369176B (en) | 1982-12-10 |
| NO146793B (en) | 1982-08-30 |
| IT1100513B (en) | 1985-09-28 |
| NO146793C (en) | 1982-12-08 |
| JPS54100300A (en) | 1979-08-07 |
| DE2754024B2 (en) | 1980-02-14 |
| NO783903L (en) | 1979-06-06 |
| DE2754024A1 (en) | 1979-06-07 |
| AU4215878A (en) | 1979-06-14 |
| JPS5922638Y2 (en) | 1984-07-05 |
| EP0002470A1 (en) | 1979-06-27 |
| ATA827678A (en) | 1982-04-15 |
| DE2754024C3 (en) | 1980-10-02 |
| AU526019B2 (en) | 1982-12-16 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MKEX | Expiry |