Method for BWP operating and user equipment using the same

1. A method for bandwidth part (BWP) operating of a serving cell, adapted to a user equipment (UE) in a first BWP, comprising:

receiving a signaling;

determining whether to switch to a second BWP from the first BWP according to the signaling; and

stopping a timer, not monitoring a physical downlink control channel (PDCCH), performing a channel state information (CSI) measurement, and stopping uplink transmission for the serving cell when staying in the first BWP, wherein the first BWP is a dormant BWP.

2. The method of claim 1 , wherein the second BWP is a non-dormant BWP.

3. The method of claim 1 , wherein the signaling indicates the second BWP and the second BWP is a non-dormant BWP.

4. The method of claim 1 , further comprising:

switching to the second BWP from the first BWP according the signaling, wherein the signaling indicates that the second BWP is a non-dormant BWP.

5. The method of claim 1 , wherein the second BWP is a pre-configured BWP.

6. The method of claim 1 , wherein the step of determining whether to switch to the second BWP from the first BWP according to the signaling comprising:

determining not to switch to the second BWP in response to the signaling indicating the UE to stay in the dormant BWP; or

determining to switch to the second BWP in response to the signaling indicating the UE to stay in a non-dormant BWP.

7. The method of claim 1 , further comprising:

staying in the first BWP in response to determining not to switch to the second BWP.

8. The method of 1 , further comprising:

stopping the timer in response to determining not to switch to the second BWP from the first BWP.

9. The method of claim 1 , further comprising:

switching to the second BWP.

10. The method of claim 1 , further comprising:

determining the second BWP from a plurality of BWPs according to at least one of the followings:

a power of the UE, a bandwidth of the second BWP, a subcarrier spacing of the second BWP, a BWP identity (ID) of the second BWP, a CORESET ID corresponding to the second BWP, a search space ID corresponding to the second BWP, or a physical downlink control channel (PDCCH) monitoring occasion of the second BWP.

11. The method of claim 1 , further comprising:

receiving a second signaling, wherein the second BWP is determined according to the second signaling.

12. The method of claim 11 , wherein the second signaling comprises a BWP identity (ID) of the second BWP, wherein the second BWP is determined according to the BWP ID.

13. The method of claim 11 , wherein the second signaling comprises a BWP hopping pattern corresponding to one or more BWPs, wherein the second BWP is determined according to the BWP hopping pattern.

14. The method of claim 1 , further comprising:

transmitting a channel state information report comprising a BWP identity (ID) of the dormant BWP.

15. The method of claim 1 , further comprising:

running a BWP inactivity timer; and

determining not to switch to the second BWP in response to the BWP inactivity timer expiry.

16. The method of claim 1 , further comprising:

receiving a second signaling after switching to the second BWP; and

starting running the timer in response to the second signaling.

17. A user equipment (UE) in a first bandwidth part (BWP), comprising:

a transceiver; and

a processor, coupled to the transceiver, wherein the processor is configured to:

receive a signaling;

determine whether to switch to a second BWP from the first BWP according to the signaling; and

stop a timer, not monitor a physical downlink control channel (PDCCH), performing a channel state information (CSI) measurement, and stop uplink transmission for the serving cell when staying in the first BWP, wherein the first BWP is a dormant BWP.