Device and method of handling an uplink transmission with sounding reference signals

1. A communication device for handling an uplink (UL) transmission with a plurality of sounding reference signals (SRSs), comprising:

at least one storage device; and

at least one processing circuit, coupled to the at least one storage device, wherein the at least one storage device stores instructions, and the at least one processing circuit is configured to execute the instructions of:

receiving a downlink (DL) signal quasi-colocated (QCLed) via a first spatial relation from a plurality of spatial relations, wherein the first spatial relation is associated with a RS from a network;

selecting a SRS corresponding to the RS from the plurality of SRSs;

performing a channel sensing procedure via a second spatial relation associated with the SRS, to obtain a result; and

performing the UL transmission via the second spatial relation to the network according to the result;

wherein the plurality of SRSs are configured by the network, and are corresponding to a plurality of SRS indices (SRIs), respectively;

wherein the first spatial relation and the second spatial relation are the same.

2. The communication device of claim 1 , wherein the communication device performs the UL transmission in a shared spectrum.

3. The communication device of claim 1 , wherein the UL transmission comprises a configured grant (CG) transmission.

4. The communication device of claim 1 , wherein the communication device performs the UL transmission via the second spatial relation associated with the SRS to the network, if the result indicates that the channel sensing procedure is successful.

5. The communication device of claim 1 , wherein the plurality of SRSs are associated with the plurality of spatial relations, and the plurality of spatial relations are associated with a plurality of RSs, respectively.

6. The communication device of claim 1 , wherein the plurality of SRSs are associated with a plurality of contention window (CW) sizes, respectively.

7. The communication device of claim 6 , wherein the communication device selects the SRS from the plurality of SRSs according to the plurality of CW sizes.

8. The communication device of claim 7 , wherein the SRS is associated with a smallest CW size of the plurality of CW sizes.

9. The communication device of claim 1 , wherein the channel sensing procedure is a listen-before-talk (LBT) procedure.

10. The communication device of claim 1 , wherein the UL transmission is not in a channel occupancy time (COT) of the network.

11. The communication device of claim 1 , wherein the UL transmission is in a COT of the network, and a downlink (DL) signal received in the COT is quasi-colocated (QCLed) with a RS different from the plurality of SRSs.

12. The communication device of claim 11 , wherein the COT is acquired according to a LBT procedure associated with the RS by the network.

13. The communication device of claim 1 , wherein the SRS and the RS are associated with the same spatial relation.

14. The communication device of claim 1 , wherein the channel sensing procedure is a short LBT procedure associated with the RS.

15. The communication device of claim 1 , wherein the UL transmission is in a COT of the network.

16. The communication device of claim 1 , wherein the DL signal is received in a COT of the network.

17. The communication device of claim 16 , wherein the COT is acquired according to a LBT procedure associated with the RS by the network.

18. The communication device of claim 1 , wherein the UL transmission comprises at least one demodulation reference signal (DMRS), and the at least one DMRS is scrambled with a sequence determined according to the SRS.

19. The communication device of claim 1 , wherein the UL transmission comprises a CG-UL control information (CG-UCI) indicating a SRI corresponding to the SRS to the network.

20. The communication device of claim 1 , wherein the instructions further comprise:

receiving a DL feedback indicator (DFI) in response to the UL transmission in a control resource set (CORESET) from the network, after performing the UL transmission.

21. The communication device of claim 20 , wherein the CORESET is not configured with any transmission configuration indication (TCI) state.

22. The communication device of claim 20 , wherein the CORESET is configured with a TCI state indicating a RS corresponding to a SRI, wherein the SRI is corresponding to the SRS.