Downlink Control Information Activating a Bandwidth Part Inactivity Timer

1 . A wireless device comprising:

one or more processors; and

memory storing instructions that, when executed by the one or more processors, cause the wireless device to:

receive, from a base station, one or more messages comprising configuration parameters of a cell, the configuration parameters comprising:

bandwidth part (BWP) parameters of a first BWP and a second BWP; and

a timer value associated with a BWP inactivity timer;

receive, in a first time interval, a first downlink control information (DCI) indicating switching from the first BWP to the second BWP as an active BWP;

in response to the first DCI:

switch from the first BWP to the second BWP as the active BWP; and

start, after the switching from the first BWP to the second BWP as the active BWP, the BWP inactivity timer based on the timer value, wherein:

the wireless device completes the switching no later than a second time interval that is a time offset after the first time interval; and

the time offset is based on a capability, of the wireless device, for BWP switching; and

switch to a default BWP in response to an expiry of the BWP inactivity timer.

2 . The wireless device of claim 1 , wherein the instructions further cause the wireless device to:

receive a command indicating:

a downlink assignment;

an uplink assignment; or

an activation of the cell; and

activate, based on the first BWP being a first active BWP indicated by the configuration parameters, the first BWP in response to receiving the command, wherein the command comprises:

a second DCI; or

a medium access control control element (MAC CE).

3 . The wireless device of claim 2 , wherein activating the first BWP comprises monitoring a downlink control channel on the first BWP.

4 . The wireless device of claim 1 , wherein switching from the first BWP to the second BWP as the active BWP comprises at least one of:

stopping monitoring a first downlink control channel on the first BWP; or

monitoring a second downlink control channel on the second BWP.

5 . The wireless device of claim 1 , wherein the instructions further cause the wireless device to:

receive at a third slot, a third DCI indicating switching to the default BWP as the active BWP; and

in response to the third DCI:

switch the active BWP to the default BWP; and

stop the BWP inactivity timer.

6 . The wireless device of claim 1 , wherein, based on switching to the second BWP as the active BWP of the cell, the instructions further cause the wireless device to:

receive downlink signals via the second BWP; or

transmit uplink signals via the second BWP.

7 . The wireless device of claim 1 , wherein, based on the second BWP being the active BWP of the cell, the instructions further cause the wireless device to transmit a channel state information (CSI) report for the second BWP.

8 . A method comprising:

receiving, by a wireless device from a base station, one or more messages comprising configuration parameters of a cell, the configuration parameters comprising:

bandwidth part (BWP) parameters of a first BWP and a second BWP; and

a timer value associated with a BWP inactivity timer;

receiving, in a first time interval, a first downlink control information (DCI) indicating switching from the first BWP to the second BWP as an active BWP;

in response to the first DCI:

switching from the first BWP to the second BWP as the active BWP; and

starting, after the switching from the first BWP to the second BWP as the active BWP, the BWP inactivity timer based on the timer value, wherein:

the wireless device completes the switching no later than a second time interval that is a time offset after the first time interval; and

the time offset is based on a capability, of the wireless device, for BWP switching; and

switching to a default BWP in response to an expiry of the BWP inactivity timer.

9 . The method of claim 8 , further comprising:

receiving a command indicating:

a downlink assignment;

an uplink assignment; or

an activation of the cell; and

activating, based on the first BWP being a first active BWP indicated by the configuration parameters, the first BWP in response to receiving the command, wherein the command comprises:

a second DCI; or

a medium access control control element (MAC CE).

10 . The method of claim 9 , wherein activating the first BWP comprises monitoring a downlink control channel on the first BWP.

11 . The method of claim 8 , wherein switching from the first BWP to the second BWP as the active BWP comprises at least one of:

stopping monitoring a first downlink control channel on the first BWP; or

monitoring a second downlink control channel on the second BWP.

12 . The method of claim 8 , further comprising:

receiving at a third slot, a third DCI indicating switching to the default BWP as the active BWP; and

in response to the third DCI:

switching the active BWP to the default BWP; and

stopping the BWP inactivity timer.

13 . The method of claim 8 , further comprising, based on switching to the second BWP as the active BWP of the cell, at least one of:

receiving downlink signals via the second BWP; or

transmits uplink signals via the second BWP.

14 . The method of claim 8 , further comprising, based on the second BWP being the active BWP of the cell, transmitting a channel state information (CSI) report for the second BWP.

15 . A non-transitory computer-readable medium comprising instructions that, when executed by one or more processors of a wireless device, cause the wireless device to:

receive, from a base station, one or more messages comprising configuration parameters of a cell, the configuration parameters comprising:

bandwidth part (BWP) parameters of a first BWP and a second BWP; and

a timer value associated with a BWP inactivity timer;

receive, in a first time interval, a first downlink control information (DCI) indicating switching from the first BWP to the second BWP as an active BWP;

in response to the first DCI:

switch from the first BWP to the second BWP as the active BWP; and

start, after the switching from the first BWP to the second BWP as the active BWP, the BWP inactivity timer based on the timer value, wherein:

the wireless device completes the switching no later than a second time interval that is a time offset after the first time interval; and

the time offset is based on a capability, of the wireless device, for BWP switching; and

switch to a default BWP in response to an expiry of the BWP inactivity timer.

16 . The non-transitory computer-readable medium of claim 15 , wherein the instructions further cause the wireless device to:

receive a command indicating:

a downlink assignment;

an uplink assignment; or

an activation of the cell; and

activate, based on the first BWP being a first active BWP indicated by the configuration parameters, the first BWP in response to receiving the command, wherein the command comprises:

a second DCI; or

a medium access control control element (MAC CE).

17 . The non-transitory computer-readable medium of claim 16 , wherein activating the first BWP comprises monitoring a downlink control channel on the first BWP.

18 . The non-transitory computer-readable medium of claim 15 , wherein switching from the first BWP to the second BWP as the active BWP comprises at least one of:

stopping monitoring a first downlink control channel on the first BWP; or

monitoring a second downlink control channel on the second BWP.

19 . The non-transitory computer-readable medium of claim 15 , wherein the instructions further cause the wireless device to:

receive at a third slot, a third DCI indicating switching to the default BWP as the active BWP; and

in response to the third DCI:

switch the active BWP to the default BWP; and

stop the BWP inactivity timer.

20 . The non-transitory computer-readable medium of claim 15 , wherein, based on switching to the second BWP as the active BWP of the cell, the instructions further cause the wireless device to:

receive downlink signals via the second BWP; or

transmit uplink signals via the second BWP.