Methods to reduce the time taken to perform cell selection during T311 after radio link failure in internet of things non-terrestrial networks
A method by a wireless device includes obtaining assistance information for identifying at least one cell for performing a cell reestablishment procedure, and taking at least one action based on the assistance information. A method by a network node includes transmitting, to a wireless device, assistance information for identifying at least one cell for performing a cell reestablishment procedure. The method may further include configuring the wireless device to performing a cell search to identify at least one cell for performing the cell reestablishment procedure based on the assistance information.
1 . A method by a wireless device comprising:
prior to a current link failing, obtaining assistance information for identifying at least one cell for performing a cell reestablishment procedure, the assistance information comprising ephemeris data;
detecting a radio link failure associated with the current link; and
after detecting the radio link failure, taking at least one action based on the assistance information, wherein the at least one action comprises:
performing a cell search to identify a particular one of the at least one cell for performing the cell reestablishment procedure based in part on the ephemeris data associated with the particular one of the least one cell; and
performing the cell reestablishment procedure for the particular one of the at least one cell.
2 . The method of claim 1 , wherein the ephemeris data is obtained from a network node.
3 . The method of claim 1 , wherein obtaining the assistance information comprises receiving the assistance information from a network node.
4 . The method of claim 1 , wherein the assistance information indicates the at least one cell.
5 . The method of claim 1 , wherein the assistance information comprises at least one of: a carrier frequency, a PCI, ephemeris data of a satellite serving the at least one cell, and a timing of SSB transmissions.
6 . The method of claim 1 , wherein the assistance information indicates that no cell is available, and the method further comprises transitioning to an inactive or idle state.
7 . The method of claim 1 , wherein performing the at least one action comprises scaling an amount of time associated with a timer that measures a time associated with a cell search procedure.
8 . The method of claim 7 , wherein scaling the amount of time associated with the timer comprises reducing the amount of time associated with the timer.
9 . The method of claim 1 , wherein performing the at least one action comprises increasing an amount of time associated with a timer that measures a time associated with a cell search procedure.
10 . The method of claim 1 , further comprising obtaining information indicating a coverage extension level of the wireless device, and wherein the at least one action is taken based on the information indicating the coverage extension level.
11 . The method of claim 10 , wherein the coverage extension level indicates that the wireless device has a coverage level that is less than a threshold, and wherein taking the at least one action comprises increasing an amount of time associated with a timer associated with performing a cell search.
12 . The method of claim 10 , wherein the coverage extension level indicates that the wireless device has a coverage level that is greater than a threshold, and wherein taking the at least one action comprises decreasing an amount of time associated with a timer associated with performing a cell search.
13 . The method of claim 1 , further comprising obtaining information indicating a location of the wireless device, and wherein the at least one action is taken based on the information indicating the location.
14 . The method of claim 13 , wherein taking the at least one action comprises increasing an amount of time associated with a timer associated with performing a cell search based on the location of the wireless device.
15 . The method of claim 13 , wherein taking the at least one action comprises decreasing an amount of time associated with a timer associated with performing a cell search based on the location of the wireless device.
16 . The method of claim 1 , further comprising obtaining information indicating a signal measurement associated with the wireless device, and wherein the at least one action is taken based on the information indicating the signal measurement.
17 . The method of claim 16 , wherein taking the at least one action comprises increasing an amount of time associated with a timer associated with performing a cell search based on the signal measurement.
18 . The method of claim 16 , wherein taking the at least one action comprises decreasing an amount of time associated with a timer associated with performing a cell search based on the signal measurement.