Cell reselection priority assignment based on performance triggers
The disclosed technology provides systems and methods for dynamically assigning cell reselection priorities (e.g., system information block (SIB) priorities) to different layers (e.g., different frequency bands or different radio access technologies (RATs)) for radio cells experiencing performance degradation. In some implementations, default SIB priorities of degraded layers are downgraded based on the severity of the performance degradation, for example, set to the lowest variable SIB priority for critical performance degradations. The adjusted SIB priorities are broadcast to user equipment (UE) to allow the UEs to perform cell reselection based on the adjusted SIB priorities. When the performance degradation is resolved, the SIB priorities revert to the default SIB priorities.
1. A user equipment (UE) in a cellular communication network comprising:
at least one hardware processor; and
at least one non-transitory memory, coupled to the at least one hardware processor and storing instructions, which, when executed by the at least one hardware processor, cause the UE to:
receive a default cell-reselection priority transmitted in system information messages broadcast in one or more system information blocks (SIBs),
wherein the cell-reselection priority assigns a priority indicator value to one or more layers that the UE is compatible with;
after receiving the default cell-reselection priority, receive an updated cell-reselection priority,
wherein the updated cell-reselection priority assigns a lower priority indicator value than a default priority indicator value to a layer of the one or more layers when the layer is undergoing a performance degradation;
perform a cell reselection in IDLE mode based on the updated cell-reselection priority thereby causing the UE to deprioritize selection of the layer that is undergoing the performance degradation;
after performing the cell reselection in IDLE mode, receive a further updated cell-reselection priority when the performance degradation is at least partially resolved; and
perform a cell reselection based on the further updated cell-reselection priority thereby causing the UE to prioritize selection of the layer whose performance degradation is at least partially resolved.
2. The UE of claim 1 , wherein the one or more layers that the UE is compatible with comprise one or more frequency bands, or one or more radio access technologies (RATs).
3. The UE of claim 1 , further comprising:
after receiving the updated cell-reselection priority, receiving the default cell-reselection priority when the layer is no longer undergoing the performance degradation.
4. The UE of claim 1 , wherein the performance degradation comprises a key process indicator (KPI) based performance degradation, an alarm-based performance degradation, a sleeping cell condition, or a UE interference based degradation.
5. The UE of claim 4 , wherein the KPI based performance degradation comprises a radio access channel (RACH) setup attempt degradation, a radio resource control (RRC) connection setup attempt degradation, an RRC success rate degradation, or an S1 setup success rate degradation.
6. The UE of claim 4 , wherein the alarm based degradation comprises a cell operation degradation alarm staying active for a defined time.
7. The UE of claim 4 , wherein the UE interference based degradation comprises a UE signal quality degradation caused by tropospheric ducting.
8. The UE of claim 4 , wherein to perform the cell reselection based on the further updated cell-reselection priority comprises causing the UE to:
assign a higher priority indicator value than the previously updated priority indicator value to a layer of the one or more layers when the performance degradation is partially resolved.
9. The UE of claim 4 , wherein to perform the cell reselection based on the further updated cell-reselection priority comprises causing the UE to:
assign the default cell-reselection priority when the performance degradation is resolved.
10. A computer-implemented method comprising:
receiving a default cell-reselection priority transmitted in system information messages broadcast in one or more system information blocks (SIBs),
wherein the cell-reselection priority assigns a priority indicator value to one or more layers that the UE is compatible with;
after receiving the default cell-reselection priority, receiving an updated cell-reselection priority,
wherein the updated cell-reselection priority assigns a lower priority indicator value than a default priority indicator value to a layer of the one or more layers when the layer is undergoing a performance degradation;
performing a cell reselection in IDLE mode based on the updated cell-reselection priority thereby causing the UE to deprioritize selection of the layer that is undergoing the performance degradation;
after performing the cell reselection in IDLE mode, receiving a further updated cell-reselection priority when the performance degradation is at least partially resolved; and
performing a cell reselection based on the further updated cell-reselection priority thereby causing the UE to prioritize selection of the layer whose performance degradation is at least partially resolved.
11. The computer-implemented method of claim 10 , wherein the one or more layers that the UE is compatible with comprise one or more frequency bands, or one or more radio access technologies (RATs).
12. The computer-implemented method of claim 10 , further comprising:
after receiving the updated cell-reselection priority, receiving the default cell-reselection priority when the layer is no longer undergoing the performance degradation.
13. The computer-implemented method of claim 10 , wherein the performance degradation comprises a key process indicator (KPI) based performance degradation, an alarm-based performance degradation, a sleeping cell condition, or a UE interference based degradation.
14. The computer-implemented method of claim 10 , wherein the KPI based performance degradation comprises a radio access channel (RACH) setup attempt degradation, a radio resource control (RRC) connection setup attempt degradation, an RRC success rate degradation, or an S1 setup success rate degradation.
15. The computer-implemented method of claim 10 , wherein the alarm based degradation comprises a cell operation degradation alarm staying active for a defined time.
16. The computer-implemented method of claim 10 , wherein the UE interference based degradation comprises a UE signal quality degradation caused by tropospheric ducting.
17. The computer-implemented method of claim 10 , wherein performing the cell-reselection based on the further updated cell-reselection priority comprises:
assigning a higher priority indicator value than the previously updated priority indicator value to a layer of the one or more layers when the performance degradation is partially resolved.
18. The computer-implemented method of claim 10 , wherein performing the cell-reselection based on the further updated cell-reselection priority comprises:
causing the UE to prioritize selection of the layer to the default cell-reselection priority when the performance degradation is resolved.
19. A system comprising:
at least one hardware processor; and
at least one non-transitory memory storing instructions, which, when executed by the at least one hardware processor, cause the system to:
receive a default cell-reselection priority transmitted in system information messages broadcast in one or more system information blocks (SIBs),
wherein the cell-reselection priority assigns a priority indicator value to one or more layers that the UE is compatible with;
after receiving the default cell-reselection priority, receive an updated cell-reselection priority,
wherein the updated cell-reselection priority assigns a lower priority indicator value than a default priority indicator value to a layer of the one or more layers when the layer is undergoing a performance degradation;
perform a cell reselection in IDLE mode based on the updated cell-reselection priority thereby causing the UE to deprioritize selection of the layer that is undergoing the performance degradation;
after performing the cell reselection in IDLE mode, receive a further updated cell-reselection priority when the performance degradation is at least partially resolved; and
perform a cell reselection based on the further updated cell-reselection priority thereby causing the UE to prioritize selection of the layer whose performance degradation is at least partially resolved.
20. The system of claim 19 , wherein to perform the further updated cell-reselection priority comprises causing the system to:
assign a higher priority indicator value than the previously updated priority indicator value to a layer of the one or more layers when the performance degradation is partially resolved, and
assign the default cell-reselection priority when the performance degradation is resolved.