Method and apparatus for call recovery in a wireless communication system
First Claim
1. A method for call recovery by a wireless mobile station, comprising:
- communicating with base stations in an active set of the mobile station;
determining if a call recovery trigger has occurred;
if the call recovery trigger has occurred, determining if a transmitter of the mobile station is enabled;
if the transmitter of the mobile station is enabled, disabling the transmitter based on a trigger condition;
starting a recovery timer after an expiration of a wait timer;
enabling the transmitter of the mobile station; and
after enabling the transmitter of the mobile station, transmitting a call recovery preamble for a predetermined time period after the expiration of the wait timer, the call recovery preamble being exclusive of and adjacent to a pilot strength measurement message and transmission of the call recovery preamble terminates before transmission of the pilot strength measurement message.
1 Assignment
0 Petitions
Accused Products
Abstract
A method and apparatus for call recovery in a wireless communication system (10). When the communication link between a mobile station (38) and a base station (32) is in trouble, the mobile station and the infrastructure prearrange potential rescue base stations (34). The source cell base station contacts all recovery-capable neighbors as potential rescuers. Each rescue base station is instructed to use a default channel for rescue transmissions. The rescue transmission is considered a call recovery operation. The mobile station establishes a soft hand-off with rescue base station, wherein the FL uses the default channel and an alternate channel. Once hand-off is complete the rescue base station discontinues use of the default channel. In one embodiment, the source cell base station provides the mobile station with the list of recovery-capable neighbors as overhead during transmissions and prior to development of the communication link problem.
48 Citations
26 Claims
-
1. A method for call recovery by a wireless mobile station, comprising:
-
communicating with base stations in an active set of the mobile station; determining if a call recovery trigger has occurred; if the call recovery trigger has occurred, determining if a transmitter of the mobile station is enabled; if the transmitter of the mobile station is enabled, disabling the transmitter based on a trigger condition; starting a recovery timer after an expiration of a wait timer; enabling the transmitter of the mobile station; and after enabling the transmitter of the mobile station, transmitting a call recovery preamble for a predetermined time period after the expiration of the wait timer, the call recovery preamble being exclusive of and adjacent to a pilot strength measurement message and transmission of the call recovery preamble terminates before transmission of the pilot strength measurement message. - View Dependent Claims (2, 3, 4, 5, 6, 7)
-
-
8. A non-transitory computer readable medium comprising instructions, the instructions when executed by the computer comprising a wireless mobile station, cause the wireless mobile station to perform operations comprising:
-
communicating with base stations in an active set of the mobile station; determining if a call recovery trigger has occurred; if the call recovery trigger has occurred, determining if a transmitter of the mobile station is enabled; if the transmitter of the mobile station is enabled, disabling the transmitter based on a trigger condition; starting a recovery timer after an expiration of a wait timer; enabling the transmitter of the mobile station; and after enabling the transmitter of the mobile station, transmitting a call recovery preamble for a predetermined time period after the expiration of the wait timer, the call recovery preamble being exclusive of and adjacent to a pilot strength measurement message and transmission of the call recovery preamble terminates before transmission of a pilot strength measurement message. - View Dependent Claims (9, 10, 11, 12, 13)
-
-
14. A wireless mobile station having call recovery, comprising:
-
means for communicating with base stations in an active set of the mobile station; means for determining if a call recovery trigger has occurred; means for determining if a transmitter of the mobile station is enabled; means for disabling the transmitter based on a trigger condition; means for starting a recovery timer after an expiration of a wait timer; means for enabling the transmitter of the mobile station; and means for transmitting a call recovery preamble for a predetermined time period after the expiration of the wait timer, the call recovery preamble being exclusive of and adjacent to a pilot strength measurement message and transmission of the call recovery preamble terminates before transmission of the pilot strength measurement message. - View Dependent Claims (15, 16, 17, 18, 19, 20)
-
-
21. A wireless mobile station, comprising:
-
a processor; and circuitry coupled to the processor configured to communicate with base stations in an active set of the mobile station, determine if a call recovery trigger has occurred, determine if a transmitter of the mobile station is enabled if the call recovery trigger has occurred, disable the transmitter based on a trigger condition if the transmitter of the mobile station is enabled, start a recovery timer after an expiration of a wait timer, enable the transmitter of the mobile station, and transmit a call recovery preamble for a predetermined time period after the expiration of the wait timer, the call recovery preamble being exclusive of and adjacent to a pilot strength measurement message and transmission of the call recovery preamble terminates before transmission of the pilot strength measurement message after enabling the transmitter of the mobile station. - View Dependent Claims (22, 23, 24, 25, 26)
-
Specification