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A radio link timeout procedure for call re-establishment is provided. A mobile station receives signals over a wireless link, determines whether there is a potential call re-establishment as defined by at least one condition, and decides whether radio link failure has occurred on the basis of the signals received over the wireless link such that while there is a potential for call re-establishment as defined by the at least one condition, a decision that a radio link failure has occurred is made earlier than if there is no potential for call re-establishment.

Claims

1. A method in a mobile station, the method comprising:

receiving signals over a wireless link;

determining whether there is a potential for call re-establishment as defined by at least one condition;

deciding whether radio link failure has occurred on the basis of the signals received over the wireless link such that while there is a potential for call re-establishment as defined by the at least one condition, a decision that a radio link failure has occurred is made earlier than if there is no potential for call re-establishment.

2. The method of claim 1 wherein deciding whether radio link failure has occurred on the basis of the signals received over the wireless link comprises:

incrementing and decrementing a first counter on the basis of signals received over the wireless link;

incrementing and decrementing a second counter on the basis of signals received over the wireless link;

wherein incrementing and decrementing the first and second counter is such that the second counter will expire before the first counter.

3. The method of claim 1 wherein deciding whether radio link failure has occurred on the basis of the signals received over the wireless link comprises:

incrementing and decrementing a counter on the basis of signals received over the wireless link;

using a first expiry value for the counter while there is a potential for call re-establishment and using a second expiry value for the counter while there is no potential for call re-establishment.

4. The method of claim 2 further comprising initializing the second counter to a value that is a defined offset from an initialization value for the first counter.

5. The method of claim 2 further comprising initializing the second counter to a value that is a defined fraction of the initialization value for the first counter.

6. The method of claim 2 further comprising setting the second counter to a value that is one of a plurality of values, the one of the plurality of values being selected based on a current value of the first counter.

7. The method of claim 2 further comprising initializing the second counter to a value independent of an initialization value for the first counter.

8. The method of claim 2 wherein:

incrementing and decrementing a first counter on the basis of signals received over the wireless link comprises incrementing and decrementing the first counter as a function of success or failure of receipt of SACCH (Slow Associated Control Channel) blocks;

incrementing and decrementing a second counter on the basis of signals received over the wireless link comprises incrementing and decrementing the second counter as a function of success or failure of receipt of SACCH blocks.

9. The method of claim 2 further comprising:

enabling the second counter only while there is a potential for call re-establishment as defined by the at least one condition.

10. The method of claim 2 further comprising:

deciding radio link failure has occurred based on the second counter only while there is a potential for call re-establishment as defined by the at least one condition.

11. The method of claim 1 wherein the at least one condition includes that the mobile station is aware that there is at least one cell that has a call re-establishment feature enabled.

12. The method of claim 1 wherein the at least one condition includes that the mobile station has a set of cell system information required to perform call re-establishment.

13. The method of claim 1 wherein the at least one condition includes that voice quality is poor as defined by a metric.

14. The method of claim 1 further comprising:

generating an indication upon deciding that radio link failure has occurred that is the same irrespective of whether there is a potential for call re-establishment.

15. The method of claim 1 wherein:

the determination of radio link failure when the at least one condition is met results in either a call re-establishment attempt or termination of a connection without any call re-establishment attempt.

16. The method of claim 1 wherein:

the determination of radio link failure when the at least one condition is met results in either a call re-establishment attempt, but does not cause termination of a connection without any call re-establishment attempt.

17. The method of claim 1 further comprising:

initiating call re-establishment upon deciding that radio link failure has occurred.

18. A mobile station configured to implement the method of claim 1.

19. A computer readable medium having computer executable instructions stored thereon which when executed by a mobile station cause the mobile station to execute the method of claim 1.