Communication device and control method thereof

1. A communication device, adapted to a communication system, the communication device comprising:

a receiving unit, for receiving a first burst in a paging message; and

a decision-making unit, for comparing a signal-to-noise ratio with a first threshold to generate a comparison result, and deciding a determination mechanism according to the comparison result, for determining whether the paging message is a dummy paging message, wherein the signal-to-noise ratio relates to a channel that the first burst travels through and wherein the deciding is achieved without reference to another paging message,

wherein when the signal-to-noise ratio is lower than the first threshold, the decision-making unit further determines whether the signal-to-noise-ratio is higher than a second threshold.

2. The communication device as claimed in claim 1 , wherein, when the signal-to-noise ratio is higher than the first threshold, the determination mechanism determines whether the paging message is the dummy paging message according to the first burst.

3. The communication device as claimed in claim 1 , wherein, when the signal-to-noise ratio is lower than the first threshold, the determination mechanism determines whether the paging message is the dummy paging message according to at least two bursts in the paging message.

4. The communication device as claimed in claim 1 , wherein, when the signal-to-noise ratio is lower than the first threshold, the decision-making unit decides the determination mechanism according to a mobile identification code of the communication device.

5. The communication device as claimed in claim 4 , wherein, the decision-making unit determines whether the mobile identification code is in a blacklist group.

6. The communication device as claimed in claim 5 , wherein when the mobile identification code is not in the blacklist group, the determination mechanism determines whether the paging message is the dummy paging message according to the first burst.

7. The communication device as claimed in claim 5 , wherein when the mobile identification code is in the blacklist group, the determination mechanism determines whether the paging message is the dummy paging message according to at least two bursts of the paging message.

8. The communication device as claimed in claim 1 , wherein when the signal-to-noise ratio is lower than the second threshold, the determination mechanism determines whether the paging message is the dummy paging message according to at least two bursts of the paging message, and wherein the second threshold is lower than the first threshold.

9. The communication device as claimed in claim 1 , wherein when the signal-to-noise ratio is in between the first threshold and the second threshold, the decision-making unit further determines whether the mobile identification code is in a blacklist group.

10. The communication device as claimed in claim 9 , wherein when the mobile identification code is not in the blacklist group, the decision-making unit determines whether the paging message is the dummy paging message according to the first burst in the paging message.

11. The communication device as claimed in claim 9 , wherein when the mobile identification code is in the blacklist group, the determination mechanism determines whether the paging message is the dummy paging message according to at least two bursts in the paging message.

12. The communication device as claimed in claim 1 , wherein when the signal-to-noise ratio is higher than the second threshold, the determination mechanism determines whether the mobile identification code conforms to a predetermined term.

13. The communication device as claimed in claim 12 , wherein the mobile identification code conforms with the predetermined term when a difference between a part of the mobile identification code and a feature vector of the dummy paging message is less than a default value.

14. The communication device as claimed in claim 12 , wherein, when the mobile identification code does not conform to the predetermined term, the determination mechanism determines whether the paging message is the dummy paging message according to the first burst, and when the mobile identification code conforms to the predetermined term, the decision-making unit determines whether the mobile identification code is in a blacklist group, and if not, the determination mechanism determines whether the paging message is the dummy paging message according to the first burst.

15. The communication device as claimed in claim 14 , wherein, when the mobile identification code conforms to the predetermined term and in the blacklist group, the determination mechanism determines whether the paging message is the dummy paging message according to at least two bursts of the paging message.

16. A control method adapted to a communication device, comprising:

(a) receiving a first burst of a paging message; and

(b) comparing a signal-to-noise ratio with a first threshold to generate a comparison result, and deciding a determination mechanism according to the comparison result to determine whether the paging message is a dummy paging message, wherein the signal-to-noise ratio relates to a channel that the first burst travels through and wherein the deciding is achieved without reference to another paging message,

wherein step (b) comprises reading a mobile identification code of the communication device when the signal-to-noise ratio is lower than the first threshold, and deciding the determination mechanism according to the mobile identification code,

determining whether the signal-to-noise ratio is higher than a second threshold when the signal-to-noise ratio is lower than the first threshold, the second threshold being lower than the first threshold; and

when the signal-to-noise ratio is lower than the second threshold, determining whether the paging message is the dummy paging message according to at least two bursts in the paging message.

17. The control method as claimed in claim 16 , further comprising:

when the signal-to-noise ratio is higher than the first threshold, determining whether the paging message is the dummy paging message according to the first burst; and

when the signal-to-noise ratio is lower than the first threshold, determining whether the paging message is the dummy paging message according to at least two bursts in the paging message.

18. The control method as claimed in claim 16 , wherein, step (b) comprises:

determining whether the mobile identification code is in a blacklist group;

when the mobile identification code is not in the blacklist group, determining whether the paging message is the dummy paging message according to the first burst; and

when the mobile identification code is in the blacklist group, determining whether the paging message is the dummy paging message according to at least two bursts in the paging message.

19. The control method as claimed in claim 16 , wherein, step (b) comprises:

determining whether the mobile identification code is in a blacklist group when the signal-to-noise ratio is lower than the first threshold and higher than the second threshold;

wherein when the mobile identification code is not in the blacklist group, the determination mechanism determines whether the paging message is the dummy paging message according to the first burst; and

when the mobile identification code is in the blacklist group, determining whether the paging message is the dummy paging message according to at least two bursts in the paging message.

20. The control method as claimed in claim 16 , wherein, step (b) comprises:

determining whether the mobile identification code conforms to a predetermined term when the signal-to-noise ratio is lower than the first threshold and higher than the second threshold; and

when the mobile identification code does not conform to the predetermined term, determining whether the paging message is the dummy paging message according to the first burst.

21. The control method as claimed in claim 20 , wherein, the mobile identification code conforms to the predetermined term when a difference between a part of the mobile identification code and a feature vector of the dummy paging message is less than a default value.

22. The control method as claimed in claim 20 , wherein, step (b) comprises:

determining whether the mobile identification is in a blacklist group when the mobile identification code conforms to the predetermined term;

when the mobile identification code is not in the blacklist group, determining whether the paging message is the dummy paging message according to the first burst; and

when the mobile identification code is in the blacklist group, determining whether the paging message is the dummy paging message according to at least two bursts in the paging message.