Bandwidth Part Configuration and Operation
A wireless device receives one or more radio resource control (RRC) messages indicating a first downlink bandwidth part (BWP) of downlink BWPs of a cell, as a first active downlink BWP of the cell. The wireless device activates, based on the one or more RRC messages, the first downlink BWP of the downlink BWPs of the cell. The wireless device receives an RRC reconfiguration of the first active downlink BWP of the cell. The RRC reconfiguration indicates that a second downlink BWP of the downlink BWPs of the cell is the first active downlink BWP of the cell. In response to the RRC reconfiguration of the first active BWP of the cell, the wireless device switches to the second downlink BWP of the cell, as an active downlink BWP of the cell.
1 . A method comprising:
receiving, by a wireless device, one or more radio resource control (RRC) messages indicating a first downlink bandwidth part (BWP), of downlink BWPs of a cell, as a first active downlink BWP of the cell;
activating, based on the one or more RRC messages, the first downlink BWP of the downlink BWPs of the cell;
receiving an RRC reconfiguration of the first active downlink BWP of the cell, wherein the RRC reconfiguration indicates that a second downlink BWP, of the downlink BWPs of the cell, is the first active downlink BWP of the cell; and
switching, in response to the RRC reconfiguration of the first active BWP of the cell, to the second downlink BWP, of the cell, as an active downlink BWP of the cell.
2 . The method of claim 1 , wherein the cell is a primary cell of a plurality of cells.
3 . The method of claim 1 , wherein the cell is a secondary cell of a plurality of cells.
4 . The method of claim 1 , wherein the first downlink BWP is different from the second downlink BWP.
5 . The method of claim 1 , wherein the first active downlink BWP is a default downlink BWP of the cell.
6 . The method of claim 1 , wherein the one or more RRC messages comprise configuration parameters, of the first downlink BWP of the cell, indicating at least one of:
a frequency location;
a bandwidth;
a value of subcarrier spacing;
cyclic prefix; and
one or more reference signal resource configuration.
7 . The method of claim 1 , wherein the activating the first downlink BWP is in response to receiving a medium access control control element indicating an activation of the cell.
8 . The method of claim 7 , further comprising monitoring a downlink control channel of the first downlink BWP in response to the activating the first downlink BWP.
9 . The method of claim 8 , further comprising starting a BWP inactivity timer, of the cell, in response to receiving, based on monitoring the downlink control channel, a downlink control information via the first downlink BWP of the cell.
10 . The method of claim 9 , further comprising switching, while the BWP inactivity timer is running, to the second downlink BWP from the first downlink BWP in response to the RRC reconfiguration of the first active downlink BWP.
11 . 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 one or more radio resource control (RRC) messages indicating a first downlink bandwidth part (BWP), of downlink BWPs of a cell, as a first active downlink BWP of the cell;
activate, based on the one or more RRC messages, the first downlink BWP of the downlink BWPs of the cell;
receive an RRC reconfiguration of the first active downlink BWP of the cell, wherein the RRC reconfiguration indicates that a second downlink BWP, of the downlink BWPs of the cell, is the first active downlink BWP of the cell; and
switch, in response to the RRC reconfiguration of the first active BWP of the cell, to the second downlink BWP, of the cell, as an active downlink BWP of the cell.
12 . The wireless device of claim 11 , wherein the cell is one of a primary cell and a secondary cell of a plurality of cells; wherein the first downlink BWP is different from the second downlink BWP; and wherein the first active downlink BWP is a default downlink BWP of the cell.
13 . The wireless device of claim 11 , wherein the one or more RRC messages comprise configuration parameters, of the first downlink BWP of the cell, indicating at least one of:
a frequency location;
a bandwidth;
a value of subcarrier spacing;
cyclic prefix; and
one or more reference signal resource configuration.
14 . The wireless device of claim 11 , wherein the activating the first downlink BWP is in response to receiving a medium access control control element indicating an activation of the cell.
15 . The wireless device of claim 14 , wherein the instructions further cause the wireless device to monitor a downlink control channel of the first downlink BWP in response to the activating the first downlink BWP.
16 . The wireless device of claim 15 , wherein the instructions further cause the wireless device to:
start a BWP inactivity timer, of the cell, in response to receiving, based on monitoring the downlink control channel, a downlink control information via the first downlink BWP of the cell; and
switch, while the BWP inactivity timer is running, to the second downlink BWP from the first downlink BWP in response to the RRC reconfiguration of the first active downlink BWP.
17 . 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 one or more radio resource control (RRC) messages indicating a first downlink bandwidth part (BWP), of downlink BWPs of a cell, as a first active downlink BWP of the cell;
activate, based on the one or more RRC messages, the first downlink BWP of the downlink BWPs of the cell;
receive an RRC reconfiguration of the first active downlink BWP of the cell, wherein the RRC reconfiguration indicates that a second downlink BWP, of the downlink BWPs of the cell, is the first active downlink BWP of the cell; and
switch, in response to the RRC reconfiguration of the first active BWP of the cell, to the second downlink BWP, of the cell, as an active downlink BWP of the cell.
18 . The non-transitory computer-readable medium of claim 17 , wherein the cell is one of a primary cell and a secondary cell of a plurality of cells; wherein the first downlink BWP is different from the second downlink BWP; and wherein the first active downlink BWP is a default downlink BWP of the cell.
19 . The non-transitory computer-readable medium of claim 18 , wherein the instructions further cause the wireless device to monitor a downlink control channel of the first downlink BWP in response to the activating the first downlink BWP.
20 . The non-transitory computer-readable medium of claim 19 , wherein the instructions further cause the wireless device to:
start a BWP inactivity timer, of the cell, in response to receiving, based on monitoring the downlink control channel, a downlink control information via the first downlink BWP of the cell; and
switch, while the BWP inactivity timer is running, to the second downlink BWP from the first downlink BWP in response to the RRC reconfiguration of the first active downlink BWP.