Anti-theft system for vehicle

1. An anti-theft system for a vehicle comprising:

parking location sensing means for sensing a present parking location of the vehicle;

user location sensing means for sensing a present location of a user of the vehicle;

distance calculating means for calculating a distance between the present parking location of the vehicle and the present location of the user of the vehicle, the calculated distance corresponding to one distance range of a plurality of distance ranges;

security level setting means for setting a security level of the anti-theft system by selecting one security level from a plurality of security levels based on the one distance range; and

changing means for changing at least two of the following based on the selected security level: security of a lock, a method for providing a warning signal, a method for sensing an anomaly, a threshold value used for sensing the anomaly, and an interval for renewing the selected security level.

2. The anti-theft system according to claim 1 , further comprising security level changing means for changing the security level of the anti-theft system.

3. The anti-theft system according to claim 1 , further comprising:

a data storage that includes vehicle theft information, wherein the vehicle theft information includes at least a location, where a vehicle theft happened in a past; and

theft risk calculating means for calculating a risk level of a theft based on a parking condition of the vehicle and the vehicle theft information, which is stored in the data storage, wherein:

the risk level of the theft indicates a probability of the theft happening to the vehicle; and

the parking condition includes at least the present parking location of the vehicle, wherein the security level setting means sets the security level of the anti-theft system also based on the risk level of the theft.

4. The anti-theft system according to claim 3 , further comprising:

schedule taking means for taking a usage schedule of the vehicle, wherein the usage schedule of the vehicle includes a future time for the vehicle to be used next; and

interval calculating means for calculating an interval between a present time and the future time for the vehicle to be used next, wherein the security level setting means sets the security level of the anti-theft system also based on the interval between the present time and the future time.

5. The anti-theft system according to claim 1 , further comprising:

cancellation condition setting means for setting a cancellation condition for canceling the set security level of the anti-theft system according to the set security level;

status sensing means for sensing a status of the vehicle;

cancellation determining means for determining that the cancellation condition is satisfied when the sensed status of the vehicle coincides with the cancellation condition; and

security level canceling means for canceling the set security level of the anti-theft system, when it is determined that the cancellation condition is satisfied.

6. The anti-theft system according to claim 1 , further comprising:

status sensing means for sensing a status of the vehicle;

intrusion sensing condition setting means for setting an intrusion sensing condition for sensing an intrusion into the vehicle according to the set security level; and

intrusion determining means for determining that the vehicle is intruded when the sensed status of the vehicle coincides with the intrusion sensing condition.

7. The anti-theft system according to claim 6 , further comprising alarming means for alarming a user of the vehicle about the intrusion into the vehicle when it is determined that the vehicle is intruded.

8. The anti-theft system according to claim 5 , further comprising user identifying means for identifying a user of the vehicle, wherein the cancellation condition further includes that a person who tries to cancel the security level is the user of the vehicle.

9. The anti-theft system according to claim 6 , further comprising user identifying means for identifying a user of the vehicle, wherein the intrusion sensing condition further includes that an intruder into the vehicle is not the user of the vehicle.

10. The anti-theft system according to claim 1 , further comprising a vehicle-mounted device, which is installed in the vehicle.

11. The anti-theft system according to claim 3 , further comprising:

a vehicle-mounted device, which is installed in the vehicle; and

a control center, which includes the data storage.

12. The anti-theft system according to claim 1 , wherein each of the plurality of security levels corresponds to a different state of a security of a lock of the vehicle.

13. The anti-theft system according to claim 1 , wherein each of the plurality of security levels corresponds to a different method for canceling a lock of the vehicle.

14. The anti-theft system according to claim 1 , wherein each of the plurality of security levels corresponds to a different method for warning.

15. The anti-theft system according to claim 1 , wherein each of the plurality of security levels corresponds to a different method for detecting theft.

16. The anti-theft system according to claim 1 , further comprising a plurality of security units corresponding to the plurality of security levels, respectively.