Method and system for collecting traffic data

1. Method for collecting traffic data with the aid of a mobile station network and terminal equipment in vehicles to be observed, the method comprising:

defining areas in the mobile station network, wherein the terminal equipment communicates with the network using one or more predetermined messages,

determining a first time by a first clock with a subscriber identity stored based on a message between the network and the terminal equipment and relating to a first area,

determining a second time by a second clock with a subscriber identity stored based on a message between the network and the same terminal equipment and relating to a second area, and

using the first time and the second time to obtain traffic data about the vehicle moving the terminal equipment by

selecting clock pairs based on the subscriber identity/subscriber identities, calculating differences of the selected time by the clock pairs,

the calculated differences are collected to form a statistic distribution, and

a characteristic magnitude is calculated for the statistic distribution.

2. Method according to claim 1 , characterized in that the areas are boundary areas in between the location areas of the mobile station network.

3. Method according to claim 1 , characterized in that the areas are boundary areas in between the routing areas of a packet radio system.

4. Method according to claim 1 , characterized in that the messages between the terminal equipment and the network are location updating requests and/or location updating accept messages.

5. Method according to claim 1 , characterized in that a value of the subscriber identity is stored when the subscriber identity changes, and the stored value of the subscriber identity is used when seeking the time by the clock.

6. Method according to claim 1 , characterized in that the distance between the first area and the second area is determined using the location information of the areas.

7. Method according to claim 1 , characterized in that the average speed of the traffic flow is calculated with the aid of the measurement and the calculated characteristic magnitude.

8. Method according to claim 7 , characterized in that a second characteristic magnitude is calculated for the statistic distribution, and a confidence limit of the traffic flow's average speed and/or an error estimate is calculated with the aid of the measurement and the second magnitude.

9. Method according to claim 1 , characterized in that the location information of the defined areas is used in order to obtain the desired traffic data.

10. Method according to claim 1 , characterized in that to determine the area use is made of measuring equipment arranged in connection with a vehicle and tracking the location areas and/or analyzing the signaling and in combination with satellite radio determination.

11. Method according to claim 1 , characterized in that calculatory determination of the location of the area is performed by utilizing the measurement results obtained from the signaling information of the mobile station network.

12. Method according to claim 1 , characterized in that a place on at least one of the roads in each area is chosen and the place is stored in the traffic data collection system.

13. Method according to claim 12 , characterized in that the said place on the road is chosen based on the reading of a recorder of the covered distance arranged in connection with the vehicle.

14. Method according to claim 12 , characterized in that the said place on the road is chosen based on the location information and a digital map base.

15. System for collecting traffic data with the aid of a mobile station network when conventional terminal equipment is located in vehicles to be observed, characterized in that the system includes

means for determination of such areas, wherein the terminal equipment communicates with the network with the aid of one or more predetermined messages,

first storing means for storing a time by a clock with the subscriber identity based on a message between the terminal equipment and the network and relating to a first area,

second storing means for storing a time by a clock with the subscriber identity based on a message between the network and the same terminal equipment and relating to a second area,

means for selecting the times which relate to the same subscriber identity,

calculating means for calculating a time difference between the selected times

means to obtain the distance between the first area and the second area,

means using said time difference and said distance for producing traffic data about a certain vehicle moving said terminal equipment,

means for collecting the calculated time differences to form a statistic distribution, and

calculating means for calculating a characteristic magnitude for the statistic distribution.

16. System according to claim 15 , characterized in that the areas are boundary areas in between the location areas of the mobile station network.

17. System according to claim 16 , characterized in that the areas are boundary areas in between the routing areas of a packet radio system.

18. System according to claim 16 , characterized in that the messages between the terminal equipment and the network are location update requests and/or location update complete messages.

19. System according to claim 15 , characterized in that the means utilizing the stored times by the clock includes paging means to page for the time by the clock based on the stored subscriber identity.

20. System according to claim 19 , characterized in that the system includes detecting means for detecting a changed subscriber identity and storing means for storing the detected changed subscriber identity.

21. System according to claim 15 , characterized in that the system includes

calculating means to calculate the average speed of the traffic flow with the aid of the measurement and the characteristic magnitude.

22. System according to claim 15 , characterized in that the system includes

calculating means to calculate a second characteristic magnitude for the statistic distribution, and

calculating means for calculating an error estimate for the traffic flow's speed with the aid of the measurement and the second magnitude.

23. System according to claim 15 , characterized in that the system includes location information of the determined areas in order to obtain traffic data.

24. System according to claim 15 , characterized in that the system further includes

means for choosing a place on at least one road in each of the area, and storing means for storing the said place on the road in the traffic data collection system.

25. System according to claim 24 , characterized in that the means for use in area determination is adapted to track the location areas or to analyze the signaling and to use satellite radio determination.

26. System according to claim 24 , characterized in that the means for use in area determination is adapted to utilize in a calculatory manner the measurement results obtained from the signaling information of the mobile station network.

27. System according to claim 24 , characterized in that the means used for choosing of the place on the road corresponds to a vehicle's recorder of the covered distance.

28. System according to claim 24 , characterized in that the means used for choosing of the place on the road is adapted to use a digital map base.