Bandwidth parts operation in multiple active bandwidth parts
A method comprises a wireless device transmitting a first preamble for a random-access procedure via a first bandwidth part of a cell and receiving a random-access response comprising a backoff indicator. The method also comprises the wireless device selecting, for transmission of a second preamble for the random-access procedure and during a backoff window associated with the backoff indicator, a second bandwidth part. Finally, based on the selection of the second bandwidth part the method comprises the wireless device transmitting via the second bandwidth part the second preamble.
1 . A method comprising:
transmitting, by a wireless device via a first bandwidth part (BWP), a first preamble for a random-access procedure;
receiving a random-access response comprising a backoff indicator;
selecting, during a backoff window associated with the backoff indicator, a second BWP for transmission of a second preamble of the random-access procedure; and
based on the selecting, during the backoff window, of the second BWP for transmission of the second preamble, transmitting via the second BWP the second preamble.
2 . The method of claim 1 , wherein the second BWP is different from the first BWP.
3 . The method of claim 1 , further comprising receiving one or more configuration parameters of the first BWP of a cell and the second BWP of the cell.
4 . The method of claim 1 , further comprising starting the backoff window associated with the backoff indicator based on the receiving the random-access response, wherein the random-access response corresponds to the first preamble.
5 . The method of claim 1 , further comprising activating the first BWP in a first slot and the second BWP in a second slot.
6 . The method of claim 1 , further comprising performing, for the random-access procedure, a first listen-before-talk (LBT) procedure comprising a first LBT on the first BWP and a second LBT on the second BWP.
7 . The method of claim 6 , wherein transmitting the first preamble via the first BWP is based on:
a channel on the first LBT being idle; and
a channel on the second LBT being busy.
8 . 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:
transmit, via a first bandwidth part (BWP), a first preamble for a random-access procedure;
receive a random-access response comprising a backoff indicator;
select, during a backoff window associated with the backoff indicator, a second BWP for transmission of a second preamble of the random-access procedure; and
based on the second BWP being selected during the backoff window and for transmission of the second preamble, selecting, transmit via the second BWP the second preamble.
9 . The wireless device of claim 8 , wherein the second BWP is different from the first BWP.
10 . The wireless device of claim 8 , wherein the instructions further cause the wireless device to receive one or more configuration parameters of the first BWP of a cell and the second BWP of the cell.
11 . The wireless device of claim 8 , wherein the instructions further cause the wireless device to start the backoff window associated with the backoff indicator based on receiving the random-access response, wherein the random-access response corresponds to the first preamble.
12 . The wireless device of claim 8 , wherein the instructions further cause the wireless device to activate the first BWP in a first slot and the second BWP in a second slot.
13 . The wireless device of claim 8 , wherein the instructions further cause the wireless device to perform, for the random-access procedure, a listen-before-talk (LBT) procedure comprising a first LBT on the first BWP and a second LBT on the second BWP.
14 . The wireless device of claim 13 , wherein the wireless device transmits the first preamble via the first BWP based on:
a channel on the first LBT being idle; and
a channel on the second LBT being busy.
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:
transmit, via a first bandwidth part (BWP), a first preamble for a random-access procedure;
receive a random-access response comprising a backoff indicator;
select, during a backoff window associated with the backoff indicator, a second BWP for transmission of a second preamble of the random-access procedure; and
based on the second BWP being selected during the backoff window and for transmission of the second preamble, transmit via the second BWP the second preamble.
16 . The non-transitory computer-readable medium of claim 15 , wherein the second BWP is different from the first BWP.
17 . The non-transitory computer-readable medium of claim 15 , wherein the instructions further cause the wireless device to receive one or more configuration parameters of the first BWP of a cell and the second BWP of the cell.
18 . The non-transitory computer-readable medium of claim 15 , wherein the instructions further cause the wireless device to start the backoff window associated with the backoff indicator based on receiving the random-access response, wherein the random-access response corresponds to the first preamble.
19 . The non-transitory computer-readable medium of claim 15 , wherein the instructions further cause the wireless device to perform, for the random-access procedure, a listen-before-talk (LBT) procedure comprising a first LBT on the first BWP and a second LBT on the second BWP.
20 . The non-transitory computer-readable medium of claim 19 , wherein the wireless device transmits the first preamble via the first BWP based on:
a channel on the first LBT being idle; and
a channel on the second LBT being busy.