Dedicated system information block request

1. A method for a user equipment (UE) for requesting a target system information block (SIB) associated with a target service, the method comprising:

receiving at least one SIB segment of a plurality of SIB segments, the plurality of SIB segments being required to assemble a target SIB;

storing the at least one SIB segment and

before all SIB segments in the plurality of SIB segments are received to assemble the target SIB, initiating a dedicated SIB request procedure by transmitting, to a serving cell, a request for the target SIB.

2. The method of claim 1 , further comprising:

starting a timer upon transmitting the request to the serving cell, wherein a second dedicated SIB request procedure is not initiated while the timer is running;

receiving remaining SIB segments in the plurality of SIB segments that are not stored at the UE;

assembling the target SIB based on the received and stored plurality of SIB segments while the timer is running; and

stopping the timer after successfully assembling the target SIB.

3. The method of claim 2 , wherein receiving the remaining SIB segments comprises receiving the remaining SIB segments from the serving cell via UE-specific downlink control signaling.

4. The method of claim 1 , further comprising:

starting a timer upon transmitting the request to the serving cell, wherein a second dedicated SIB request procedure is not initiated while the timer is running;

receiving, from the serving cell, a second plurality of SIB segments associated with the target SIB;

assembling the target SIB based on the received second plurality of SIB segments while the timer is running;

dropping the stored at least one SIB segment of the plurality of SIB segments after assembling the target SIB; and

stopping the timer after successfully assembling the target SIB based on the received second plurality of SIB segments.

5. The method of claim 4 , wherein receiving the second plurality of SIB segments comprises receiving the second plurality of SIB segments after switching from a current active down link (DL) bandwidth part (BWP) to a second active DL BWP that is configured with at least one common search space for receiving system information.

6. The method of claim 1 , further comprising:

after transmitting the request, receiving, from the serving cell, the target SIB via a UE-specific downlink control signaling; and

dropping the stored at least one SIB segment of the plurality of SIB segments after receiving the target SIB.

7. The method of claim 1 , wherein initiating the dedicated SIB request procedure comprises initiating the dedicated SIB request procedure when the UE is not configured with any common search space for receiving system information on any of currently active downlink bandwidth parts (BWPs) associated with the UE.

8. The method of claim 1 , wherein the target service comprises a new radio (NR) sidelink communication service and the target SIB comprises an NR sidelink radio configuration including an access stratum (AS) configuration for the UE to implement the NR sidelink communication service.

9. The method of claim 8 , further comprising:

selecting a second serving cell to move from the serving cell; and

after moving to the second serving cell, implementing the NR sidelink communication service based on the NR sidelink radio configuration included in the target SIB received in the serving cell after determining that the target SIB is still valid on the second serving cell.

10. The method of claim 8 , further comprising:

switching a radio resource control (RRC) state of the UE from an RRC Connected state to one of an RRC Inactive state or an RRC Idle state; and

implementing the NR sidelink communication service based on the NR sidelink radio configuration included in the target SIB after switching the RRC state of the UE.

11. A user equipment (UE), comprising:

one or more non-transitory computer-readable media storing one or more computer-executable instructions for requesting a target system information block (SIB) associated with a target service; and

at least one processor coupled to the one or more non-transitory computer-readable media, and configured to execute the one or more computer-executable instructions to:

receive at least one SIB segment of a plurality of SIB segments, the plurality of SIB segments being required to assemble a target SIB;

store the at least one SIB segment; and

before all SIB segments in the plurality of SIB segments are received to assemble the target SIB, initiate a dedicated SIB request procedure by transmitting, to a serving cell, a request for the target SIB.

12. The UE of claim 11 , wherein the at least one processor is further configured to execute the one or more computer-executable instructions to:

start a timer upon transmitting the request to the serving cell, wherein a second dedicated SIB request procedure is not initiated while the timer is running;

receive remaining SIB segments in the plurality of SIB segments that are not stored at the UE;

assemble the target SIB based on the received and stored plurality of SIB segments while the timer is running; and

stop the timer after successfully assembling the target SIB.

13. The UE of claim 12 , wherein receiving the remaining SIB segments comprises receiving the remaining SIB segments from the serving cell via UE-specific downlink control signaling.

14. The UE of claim 11 , wherein the at least one processor is further configured to execute the one or more computer-executable instructions to:

start a timer upon transmitting the request to the serving cell, wherein a second dedicated SIB request procedure is not initiated while the timer is running;

receive, from the serving cell, a second plurality of SIB segments associated with the target SIB;

assemble the target SIB based on the received second plurality of SIB segments while the timer is running;

drop the stored at least one SIB segment of the plurality of SIB segments after assembling the target SIB; and

stop the timer after successfully assembling the target SIB based on the received second plurality of SIB segments.

15. The UE of claim 14 , wherein receiving the second plurality of SIB segments comprises receiving the second plurality of SIB segments after switching from a current active down link (DL) bandwidth part (BWP) to a second active DL BWP that is configured with at least one common search space for receiving system information.

16. The UE of claim 11 , wherein the at least one processor is further configured to execute the one or more computer-executable instructions to:

after transmitting the request, receive, from the serving cell, the target SIB via a UE-specific downlink control signaling;

drop the stored at least one SIB segment of the plurality of SIB segments after receiving the target SIB.

17. The UE of claim 11 , wherein initiating the dedicated SIB request procedure comprises initiating the dedicated SIB request procedure when the UE is not configured with any common search space for receiving system information on any of currently active downlink bandwidth parts (BWPs) associated with the UE.

18. The UE of claim 11 , wherein the target service comprises a new radio (NR) sidelink communication service and the target SIB comprises an NR sidelink radio configuration including an access stratum (AS) configuration for the UE to implement the NR sidelink communication service.

19. The UE of claim 18 , wherein the at least one processor is further configured to execute the one or more computer-executable instructions to:

select a second serving cell to move from the serving cell; and

after moving to the second serving cell, implement the NR sidelink communication service based on the NR sidelink radio configuration included in the target SIB received in the serving cell after determining that the target SIB is still valid on the second serving cell.

20. The UE of claim 18 , wherein the at least one processor is further configured to execute the one or more computer-executable instructions to:

switch a radio resource control (RRC) state of the UE from an RRC Connected state to one of an RRC Inactive state or an RRC Idle state; and

implement the NR sidelink communication service based on the NR sidelink radio configuration included in the target SIB after switching the RRC state of the UE.