DEVICE AND METHOD FOR TRAFFIC SURVEILLANCE

• US 20110121995A1
• Filed: 03/29/2010
• Published: 05/26/2011
• Est. Priority Date: 05/28/2009
• Status: Active Grant

• Current Assignee: Sensebit AB
• Original Assignee: Sensebit AB
• Inventors: Nilvér, Karl, Zettergren, Fredrik, Söderberg, Patrik, Kulander, David
• Granted Patent: US 8,773,287 B2
• Time in Patent Office: Days
• US Class Current: 340/933
• CPC Class Codes: G08G 1/042 using inductive or magnetic detectors

Abstract

A vehicle detector (10) comprises a vehicle sensor (14) arranged for sensing disturbances caused by a vehicle, a digitizer of a microprocessor (20) connected to the vehicle sensor (14). The vehicle detector (10) further comprises a memory (18) connected to the digitizer and arranged for storing the digital representation, an antenna (12) and a transmitter of a radio unit (40). The microprocessor (20) also comprises a controller arranged for controlling operation of the vehicle sensor (14), and the transmitter. The vehicle detector has a housing (49) enclosing the vehicle sensor (14), the digitizer, the memory, the transmitter and the controller. The housing (49) provides protection against mechanical damage and moisture, thereby enabling the housing to be placed under ground. The antenna (12) is provided outside the housing (49) and at a distance from the housing (49) for enabling placement of the antenna (12) within a roadway surface coating.

Claims

1. Vehicle detector, comprising:

a vehicle sensor arranged for sensing disturbances caused by a vehicle;

a digitizer connected to said vehicle sensor and arranged for encoding a signal from said vehicle sensor into a digital representation;

a memory connected to said digitizer and arranged for storing said digital representation;

an antenna;

a transmitter connected to said memory and said antenna;

a controller arranged for controlling operation of said vehicle sensor, said digitizer, said memory and said transmitter;

a battery powering said vehicle sensor, said transmitter and said receiver;

and a housing enclosing said vehicle sensor, said digitizer, said memory, said transmitter and said controller;

said housing providing protection against mechanical damage and moisture for said vehicle sensor, said digitizer, said memory, said transmitter and said controller, thereby enabling said housing to be placed under ground;

said antenna is provided outside said housing and at a distance from said housing for enabling placement of said antenna within a roadway surface coating; and

said controller is arranged for turning off at least one of said transmitter, said receiver, and said vehicle sensor during a predetermined inactivity period and for activating said transmitter and said receiver and transmitting a request for further instructions when said inactivity period is ended.

2. Vehicle detector according to claim 1, wherein a receiver, which together with said transmitter is arranged for communication with a cellular communication system.

3. Vehicle detector according to claim 2, wherein said cellular communication system provides a random access channel.

4. Vehicle detector according to claim 2, wherein said controller is arranged for controlling communication with a traffic surveillance node via said cellular communication system.

5. Vehicle detector according to claim 1, wherein said controller is arranged for powering said vehicle sensor if measurement instructions are received.

6. Vehicle detector according to claim 1, further comprising a plurality of antennas provided outside said housing and at a distance from said housing for enabling placement of said plurality of antenna at different depths within a roadway surface coating.

7. Vehicle detector according to claim 6, wherein said controller is arranged to determine an antenna of said plurality of antennas having best radio conditions relative to a base station of said cellular communication system and to control said transmitter to utilise said highest positioned operable antenna for transmissions.

8. Vehicle detector according to claim 1, wherein at least one antenna is provided within a volume filled with a material having mechanical properties similar to a roadway surface coating into which said antenna is intended to be placed, said volume being mechanically attached to said housing.

14. Vehicle detector according to claim 3, wherein said controller is arranged for controlling communication with a traffic surveillance node via said cellular communication system.

15. Vehicle detector according to claim 2, wherein said controller is arranged for powering said vehicle sensor if measurement instructions are received.

16. Vehicle detector according to claim 3, wherein said controller is arranged for powering said vehicle sensor if measurement instructions are received.

17. Vehicle detector according to claim 4, wherein said controller is arranged for powering said vehicle sensor if measurement instructions are received.

18. Vehicle detector according to claim 2, further comprising a plurality of antennas provided outside said housing and at a distance from said housing for enabling placement of said plurality of antenna at different depths within a roadway surface coating.

19. Vehicle detector according to claim 3, further comprising a plurality of antennas provided outside said housing and at a distance from said housing for enabling placement of said plurality of antenna at different depths within a roadway surface coating.

20. Vehicle detector according to claim 4, further comprising a plurality of antennas provided outside said housing and at a distance from said housing for enabling placement of said plurality of antenna at different depths within a roadway surface coating.

9. Method for providing traffic information, comprising the steps of:

sensing disturbances caused by a vehicle;

digitalizing signals of said disturbances into a digital representation;

storing said digital representation; and

transmitting signals to a traffic surveillance node by use of radio signals;

said steps of sensing, digitalizing and storing are performed in a device placed under ground;

said step of transmitting comprises the step of providing said signals to be transmitted over a distance to an antenna placed within a roadway surface coating,

disabling performing of said steps of sensing disturbances, transmitting signals and receiving signals during a predetermined inactivity period; and

performing said step of transmitting signals and transmitting a request for further instructions when said inactivity period is ended.

10. Method according to claim 9, comprising the further step of receiving signals from said traffic surveillance node, said step of transmitting and said step of receiving are performed according to a cellular communication system standard.

11. Method according to claim 9, comprising the step of initiating said step of transmitting a request for further instructions by sending a request on a random access channel of said cellular communication system.

12. Method according to claim 9, comprising the step of re-enabling said steps of sensing disturbances in response to received measurement instructions.

13. Method according to claim 9, wherein said step of transmitting signals comprises transmitting of retrieved said digital representations to said traffic surveillance node, said digital representations being digital representations of entire signal shapes of signals of said sensed disturbances.