Synchronization block association and system information reception
Systems, methods, and instrumentalities are described herein that may be associated with SS block (SSB) timing acquisition (e.g., for new radio unlicensed (NR-U) operations). A wireless transmit receive unit (WTRU) may detect/decode an SSB. The WTRU decoding the SSB may include the WTRU decoding a PBCH payload. The PBCH payload may be scrambled with a first scrambling code, channel coded, and scrambled with a second scrambling code. The WTRU may acquire information associated with the SSB that includes one or more of: a transmission occasion time index, a block time index, or a time offset. The WTRU may use one or more of the acquired parameters to determine a timing associated with the SSB.
1 . A wireless transmit receive unit (WTRU) comprising:
a processor configured at least to:
receive, in a first transmission occasion, a first synchronization signal (SS)/physical broadcast channel (PBCH) block (SSB), wherein the first SSB is associated with a second transmission occasion that is different from the first transmission occasion;
decode the first SSB, wherein being configured to decode the first SSB comprises being configured to decode a PBCH payload, a transmission occasion time index, a block time index, and a new radio unlicensed time offset of the first SSB, wherein the PBCH payload is scrambled with a first scrambling code, is channel coded, and is scrambled with a second scrambling code, and wherein the transmission occasion time index, the block time index, and the new radio unlicensed time offset are channel coded, scrambled with the second scrambling code, and not scrambled with the first scrambling code, wherein the first scrambling code is a function of a system frame number and the new radio unlicensed time offset, and wherein the second scrambling code is a function of the transmission occasion time index and the new radio unlicensed time offset;
monitor a maximum number of SSB Tx occasions (M) based on the PBCH payload;
determine, based on the transmission occasion time index, the block time index, and the new radio unlicensed time offset, new radio unlicensed timing information of the first SSB;
receive a wake-up signal that indicates a new radio unlicensed monitoring mode;
on a condition that the new radio unlicensed monitoring mode is a first monitoring mode, monitor one (CORESET) associated with the first SSB;
on a condition that the new radio unlicensed monitoring mode is a second monitoring mode, monitor a subset of CORESETs associated with the first SSB; and
on a condition that the new radio unlicensed monitoring mode is a third monitoring mode, monitor all CORESETs associated with the first SSB.
2 . The WTRU of claim 1 , wherein the processor is further configured to decode a second SSB, wherein if the second SSB is from the first transmission occasion, a determination of timing information associated with the second SSB does not use transmission occasion time index information.
3 . The WTRU of claim 1 , wherein the first transmission occasion is Transmission Occasion 0 .
4 . The WTRU of claim 1 , wherein being configured to determine the new radio unlicensed timing information comprises the processor being further configured to determine one or more of: a frame boundary, a subframe boundary, a slot boundary, or a symbol timing.
5 . A method implemented in a wireless transmit receive unit (WTRU), the method comprising:
receiving, in a first transmission occasion, a first synchronization signal (SS)/physical broadcast channel (PBCH) block (SSB), wherein the first SSB is associated with a second transmission occasion that is different from the first transmission occasion;
decoding the first SSB, wherein decoding the first SSB comprises decoding a PBCH payload, a transmission occasion time index, a block time index, and a new radio unlicensed time offset of the first SSB, wherein the PBCH payload is scrambled with a first scrambling code, is channel coded, and is scrambled with a second scrambling code, and wherein the transmission occasion time index, the block time index, and the new radio unlicensed time offset are channel coded, scrambled with the second scrambling code, and not scrambled with the first scrambling code, wherein the first scrambling code is a function of a system frame number and the new radio unlicensed time offset, and wherein the second scrambling code is a function of the transmission occasion time index and the new radio unlicensed time offset;
monitoring a maximum number of SSB Tx occasions (M) based on the PBCH payload;
determining, based on the transmission occasion time index, the block time index, and the new radio unlicensed time offset, new radio unlicensed timing information of the first SSB;
receiving a wake-up signal that indicates a new radio unlicensed monitoring mode;
on a condition that the new radio unlicensed monitoring mode is a first monitoring mode, monitoring one (CORESET) associated with the first SSB;
on a condition that the new radio unlicensed monitoring mode is a second monitoring mode, monitoring a subset of CORESETs associated with the first SSB; and
on a condition that the new radio unlicensed monitoring mode is a third monitoring mode, monitoring all CORESETs associated with the first SSB.
6 . The method of claim 5 , further comprising decoding a second SSB, wherein if the second SSB is from the first transmission occasion, a determination of timing information associated with the second SSB does not use transmission occasion time index information.
7 . The method of claim 5 , wherein the first transmission occasion is Transmission Occasion 0 .
8 . The method of claim 5 , wherein determining the new radio unlicensed timing information comprises determining one or more of: a frame boundary, a subframe boundary, a slot boundary, or a symbol timing.