Methods and related devices for transmitting identification information of user equipment during random access procedure

1. A method performed by a User Equipment (UE) for wireless communications, the method comprising:

receiving a Random Access Response (RAR) comprising an Uplink (UL) grant from a base station, the UL grant indicating a first resource allocation;

transmitting a first part of a UE Identity (ID) to the base station based on the first resource allocation;

deriving a second resource allocation from the first resource allocation by shifting the first resource allocation in a time domain;

transmitting a second part of the UE ID to the base station based on the second resource allocation; and

receiving a contention resolution message from the base station, wherein the contention resolution message comprises a UE contention resolution ID determined based on the first part of the UE ID and the second part of the UE ID.

2. The method of claim 1 , wherein the first part of the UE ID is transmitted in a first Common Control Channel (CCCH) Service Data Unit (SDU), and the second part of the UE ID is transmitted in a second CCCH SDU.

3. The method of claim 2 , wherein the UE contention resolution ID comprises the first CCCH SDU and the second CCCH SDU.

4. The method of claim 2 , wherein the UE contention resolution ID is represented by a partial UE ID that consists of a portion of the first CCCH SDU and a portion of the second CCCH SDU.

5. The method of claim 2 , wherein the UE contention resolution ID is represented by the first CCCH SDU.

6. The method of claim 1 , further comprising:

receiving a Medium Access Control (MAC) Control Element (CE) from the base station;

wherein the MAC CE comprises a bit field configured to indicate to the UE to transmit the second part of the UE ID.

7. A User Equipment (UE) comprising:

one or more non-transitory computer-readable media having computer-executable instructions embodied thereon;

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

receive a Random Access Response (RAR) comprising an Uplink (UL) grant from a base station, the UL grant indicating a first resource allocation;

transmit a first part of a UE Identity (ID) to the base station based on the first resource allocation;

derive a second resource allocation from the first resource allocation by shifting the first resource allocation in a time domain;

transmit a second part of the UE ID to the base station based on the second resource allocation;

and

receive a contention resolution message from the base station, wherein the contention resolution message comprises a UE contention resolution ID determined based on the first part of the UE ID and the second part of the UE ID.

8. The UE of claim 7 , wherein the first part of the UE ID is transmitted in a first Common Control Channel (CCCH) Service Data Unit (SDU), and the second part of the UE ID is transmitted in a second CCCH SDU.

9. The UE of claim 8 , wherein the UE contention resolution ID comprises the first CCCH SDU and the second CCCH SDU.

10. The UE of claim 8 , wherein the UE contention resolution ID is represented by a partial UE ID that consists of a portion of the first CCCH SDU and a portion of the second CCCH SDU.

11. The UE of claim 8 , wherein the UE contention resolution ID is represented by the first CCCH SDU.

12. The UE of claim 7 , wherein the at least one processor is further configured to execute the computer-executable instructions to:

receive a Medium Access Control (MAC) Control Element (CE) from the base station;

wherein the MAC CE comprises a bit field configured to indicate to the UE to transmit the second part of the UE ID.